T H EC L IN I CA L S ER ER I ES
GU I D E
J C Da Dav venpo enport rt,, R M Basker, J R Heath, J P Ralph & P 0 Glan lant t
A CLI LINI NICAL CAL GUIDE T! REM!"ABLE PARTIAL DENTURES
T h e a #t # t h o r$ r $ t at at $v e re%e re n &e %o r 'e nt n t al a l p ra ra &t $ t $o $ o n e rs a n ' s t #'ents
Contents Preface
v
Acknowledgements Part I -P at ie nt assessment The removable partial dentu denture re equation 2 Need and demand Management options for the 3 for treatment partially dentate patient dentate patient 4 !"s and the elderly # The anatomy of the denture$bearing areas % Ja relationships Information gathering( history) ' e*amination) diagnosis and treatment planning + !reliminary impressions , -rti.ulators Part Prepara paration tion of the mouth mou th 2 $ Pre
/0 // /2 /3 /4 /#
Initial prostheti. treatment Initial prostheti. 1urger y !eriodontal treatment rthodonti. treatment onservative treatment Tooth preparation
Part 3 $ /% /' /+ /, 20 2/ 22
Prosthetic treatment
or5ing impressions e.ording the 6a relationship Trial insertion of the metal frameor5 -ltered .ast te.hnique Triall insertion Tria inserti on of a*ed $up dentures Insertion of the .omple .ompleted ted d enture evie
Further reading Index
VI
3 5 1 5 21 2 5 3 9 33 4 7 53 57 5 9 69 7 1 7 5 8 7 9 7 91 1 8 99 10 7 111 115 12 3 1 3 12 3 9 13 7
Contents Preface
v
Acknowledgements Part I -P at ie nt assessment The removable partial dentu denture re equation 2 Need and demand Management options for the 3 for treatment partially dentate patient dentate patient 4 !"s and the elderly # The anatomy of the denture$bearing areas % Ja relationships Information gathering( history) ' e*amination) diagnosis and treatment planning + !reliminary impressions , -rti.ulators Part Prepara paration tion of the mouth mou th 2 $ Pre
/0 // /2 /3 /4 /#
Initial prostheti. treatment Initial prostheti. 1urger y !eriodontal treatment rthodonti. treatment onservative treatment Tooth preparation
Part 3 $ /% /' /+ /, 20 2/ 22
Prosthetic treatment
or5ing impressions e.ording the 6a relationship Trial insertion of the metal frameor5 -ltered .ast te.hnique Triall insertion Tria inserti on of a*ed $up dentures Insertion of the .omple .ompleted ted d enture evie
Further reading Index
VI
3 5 1 5 21 2 5 3 9 33 4 7 53 57 5 9 69 7 1 7 5 8 7 9 7 91 1 8 99 10 7 111 115 12 3 1 3 12 3 9 13 7
Part P Patient 1atient assessment art / of of this boo5 opens by by ma5ing ma5ing the importan impor tantt distin.tion distin. tion beteen the need and an a..ount of the various various management options for the partiall partially y dentate patient 7.hapter foll o99 The in.reasing ly partial pertine nt pertinent sub6e.t of !" !"s s and the elderly is is .on and38 thefollo demand forin.reasingly removable denture 7!"8 treatment9 - dis.ussion of sidered ne*t 7.hapter 48) folloed by a reminder of the relevant relevant aspe.ts of of intra$oral intra$o ral anatomy) 6a and 6a an dand o..lusal relationships 7.hapters # andfitting %89 an !" 7.hapter 28) the and advantages disadvantages that .an result from :y applying this 5noledge during the history ta5ing and e*amination of the patient) information is obtained to develop a diagnosis and a provisional treatment plan 7.hap ter '89 ;oever) before the latter .an be finalised) it is ne.essary to e*amine study .asts obtained from preliminary impressions impressions of the patient
P
Need and demand for
he term
ing the differen.e beteen need and demand prompts to have) hilst
T
Figure 1.1 (hether or not a re)ova* le part$al 'ent#re +RPD $s -orn *. the pat$ent $s 'epen'ent #pon se l%/)ot$vat$on In a U1 s#rve. people -ere aske' , 2I% .o# ha' several )$ss$n3 teeth at the *a&k -o#l' .o# pre%er to have an RPD or )ana3e -$tho#t4 2 The &hart sho-s that )ost people -o#l' pre%er to )ana3e -$tho#t an' that the pre%eren&e 3ro-s stron3er -$th $n&reas$n3 a3e It $s al)ost as $% the lon3er the person has )ana3e' to avo$' 'ent#res the stron3er $s the -$sh to 'o -$tho#t the)
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A clinical clinical guide guide to removable removable partial dentures Figure 1.2
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In the sa)e st#'. people -ere aske' , 2Do .o# %$n' the tho#3ht o% hav$n3 a part$al 'ent#re to repla&e so)e o% .o#r teeth ver. #psett$n3, a l$ttle #psett$n3 or not at all #psett$n342 !verall , onl. ;06 %o#n' the $'ea o% hav$n3 'ent#res not at all #psett$n3 A *reak'o-n o% the ans-ers *. a3e $s sho-n $n the &hart A3a$n , there $s a s#33est$on that ol'er people ten' to %$n' the tho#3ht o% an RP! )ore #psett$n3 than 'o the .o#n3
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=or missing posterior teeth) the .on.ept of the shortened dental ar.h 71"-8 is relevant9 ;ere the needs for oral health and
normal fun.tion .an be satisfied satisfied by by the presen the presen.e .e of natural teeth no further distally than the se.ond se.ond premolars9 premolars9
Figure 1.3 The SDA &on&ept +see Chapter > $s *ase' on the %ollo-$n3 %ollo-$n3 o*servat$ons ol'er people &an #s#all. %#n&t$on a'eF#atel. -$th a s$3n$%$&antl. s$3n$%$&antl . r e'#&e' n#)*er o% teeth the prov$s$on o% a '$stal etens$on RP! ten's not to &ontr$*#te an. s$3n$%$&ant %#n&t$onal *ene%$ts the repla&e)ent o% )$ss$n3 poster$or teeth sho#l' *e 'r$ven *. 'e)an' an' not *. nee'
Figure 1.4
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or ho- )an. people $s the SDA &on&ept a v$a*le propos$t$on4 The per&enta3e o% the U1 a'#lt pop#lat$on that possesse' %o#r 23oo'2 F#a'rants -as %o#n' to *e :;6 The relat$onsh$p to a3e $s sho-n $n the &hart The n#)*er o% people -ho )$3ht have a %#n&t$onal SDA % alls 'ra)at$&all. -$th a3e Nevertheless , there $s a r$sk that a &ons$'era*le n#)*er o% ol'er people &o#l' -ell *e prov$'e' -$th RPDs on the a'v$&e o% a 'ent$st an' .et %a$l to nee' the) or even -ear the)
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In .hapter to there is an a..ount of the real real benefits benefits that th at .an providing an !" for any any patient9 patient9 a..rue from earing !"s) as ell as illustration of the tissue D"oes the patient really ant an !"?< 7the 7the patie patient
#$e removable partial denture euation
he title of this .hapter requires immediate e*planation9 The term
T
F The patient
F The essentia essenti al oral fun.tions fun.tion s of appea appe aran.e) masti.ation and spee.h9 I t is only only after this analy analysi siss has been .ompleted that the de.ision of hether or not to treat a parti.ular patient .an be ta5en9 =or =or e*ampl e*ample) e) prostheti. treatment must not begin until it has been verified that there is a signifi.ant redu.tion in one or more of the essential essential oral fun.tions9 - simple simple determination of the number and position of the remaining teeth is not a suffi.ient foundation for ma5ing the de.ision of hether or not to initiate treatment9 I % it is indi.ated ) a treatment plan is then devised identifying the various stages stage s and the most appropriate type of prosthesis9
&enefits of 'Ps The potential benefits of !"s !" s hi.h ill be .onsidered in this thi s se.tion are their .ontribution to the folloing9 folloing 9 F F F F
-ppearan.e9 1pee.h9 Masti.ation 9 Maintaining the health of the masti.ator y masti.ator y system stem(( $ preventing undesirable tooth movement B $ improving distribution of o..lusal load9 F !reparation for .omplete dentures9
Figure 29 1 / Appearance The restorat$on o% the )$ss$n3 5<, 5< , 55 an' <5 #n'en$a*l. *ene%$t th$s pat$ent , an 58 .ear/ol' 3$rl , an' the )ot$vat$on to -ear the 'ent#re $s # n'erstan'a*l. stron3 Part$lar attent$on has *een pa$' to the appearan&e o% the 'ent#re *. the &are%#l &ho$&e o% art$%$&$al teeth an' 'es$3n o% the %lan3e A %lan3e A n at#ral appearan&e has *een &reate' *. #s$n3 a 2ve$ne' 2 a&r.l$&, *. repro'#&$n3 the pre/etra&t$on %or) o% alveolar r$'3e an' *. )ak$n3 the '$stal )ar3$n o% the %lan3e th$n an' $rre3#lar, th#s )ask$n3 the trans$t$on %ro) %lan3e to a'a&ent )#&osa
s
A clinical guide to removable partial dentures
Figure 2 .2a and b -
Appearance
Not onl. )a. an RP! help to restore appearan&e *#t $t )a. a&t#all. $)prove $t +aTh$s pat$ent 2s )a$llar. lateral $n&$sors ha' never 'evelope' an' she -as &on&erne' a*o#t the spa&$n3 o% the anter$or teeth +* The &o)*$nat$on o% ortho'ont$& )ove)ent o% the &entral $n&$sors an' the pro v$s$on o% RP!s $)prove' the appearan&e
Figure 2 .3 Appearance I% an $n&$sor $s not repla&e' soon a%ter e tra&t$on , s#&&ess%#l treat)ent at a later 'ate )a. *e &o)pro)$se' Here , the a'a&ent teeth have 'r$%te' $nto the #nrestore' <5 spa&e The re'#&e' spa&e 'oes not allo- %or an art$%$&$al tooth o% a real$st$& s$e to *e #se' on a 'ent#re I% a reasona*le aesthet$& res#lt $s to *e o*ta$ne' the spa&e )#st *e re esta*l$she' *. ortho'ont$& treat)ent
Figure 2.4 /
Speech
The loss o% )a$llar. anter$or teeth )a. prevent the &lear repro'#&t$on o% &erta$n so#n's , part$larl. the 22 an' 2"2 -h$&h are )a'e *. the lo-er l$p &onta&t$n3 the e'3es o% the )a $llar. $n&$sors The repla&e)ent o% )$ss$n3 )a$llar. anter$or teeth -$ll )ake a s$3n$%$&ant &ontr$*#t$on to t he F#al$t. o% spee&h
Figure 2. # $
Mastication
($th )o'ern %oo's an' )etho's o% preparat$on $t $s #nl$kel. that a pat$ent -$ll s#%%er %ro) )aln#tr$t$on even tho#3h a lar3e n#)*er o% teeth are )$ss$n3 Ho-ever , the 3aps that ar$se thro#3h the loss o% poster$or teeth re'#&e the e%%$&$en& . o% )ast$&at$on the *ol#s o% %oo' $s allo-e' to sl$p $nto the e'ent#lo#s areas an' th#s es&ape the &r#sh$n3 an' shear$n3 a&t$on o% the re)a$n$n3 teeth An RP ! -$ll p reven t th$s es&ape o% the *ol#s an' th#s &ontr$*#te to e%%$&$ent )ast$&at$on
!
#$e removable partial denture euation Maintaining the health of the masticatory system The provision of an !" .an ma5e a positive .ontribution to oral health by preventing) or minimising) the undesirable .onse quen.es of tooth loss) as des.ribed in the folloing paragraphs9 Figure < 6 / Preventing undesirable tooth oveent ( hen teeth are lost %ro) a 'ental ar&h the teeth a'a&ent to the e'ent#lo#s spa&e )a. t$lt an' )ove $nto that spa&e Th$s 'r$%t$n3 o% eeth opens #p %#rther spa&es -h$&h $n&rease the opport#n$t. %or %oo' $)pa&t$on an' plaF#e %or)at$on , en&o#ra3$n3 $n%la))at$on o% the per$o'ontal t$ss#es an' 'e&al&$%$&at$on o% the pro$)al s#r%a&es o% the teeth Inev$ta*l., the lon3er s#&h spa&es re)a$n #nrestore' , the 3reater the &han&e o% tooth )ove)ent (hen teeth are lost %ro) an oppos$n3 ar& h over/er#pt$on )a. o&r -$th s$)$lar 'eleter$o#s e%%e&ts on the oral health Ho-ever , $% tooth )ove)ent has not o&rre' $n sp$te o% the eeth *e$n3 lost so)e .ears prev$o#sl. , $t &an *e ass#)e' that $t $s not 3o$n3 to o&r s#*seF#entl.
Fi gure 29 ! /
Preventing undesirable tooth oveent
The lon3/ter) a*sen&e o% anta3on$sts has res#lte' $n over /er#pt$on o% )a$llar. an' )an'$*#lar teeth The teeth are v$rt#all. &onta&t$n3 the oppos$n3 e'ent#lo#s r$'3es &reat$n3 )aor pro*le)s $% RPDs have to *e prov$'e'
Fi gure < " /
Preventing undesirable tooth oveent
In th$s ea)ple , 59 has over/er#pte' to s#&h an etent that $t has lost )ost o% $ts *on. s#pport Etra&t$on o% the tooth $s $nev$ta*le
Figure 29, $
Iproved distribution o# occlusal load
The loss o% a lar3e n#)*er o% teeth p#ts an $n&reas$n3 %#n&t$onal *#r'en on the re)a$n$n3 teeth In th$s ea)ple there $s e $st$n3 pe2r$o'ontal '$sease The $n&rease' %#n&t$onal loa' has hastene' the 'estr#&t$on o% the per$o'ontal atta&h)ents o% the )a $llar. anter$or teeth , - h$&h have *e&o)e $n&reas$n3l . )o*$le an' have 'r$%te' la*$all.
7
A clinical guide to removable partial dentures Figure < 1$ /
Iproved distribution o# occlusal load
I% the per$o'ontal atta&h)ents o% the re)a$n$n3 teeth are health. , the $n&rease' loa' )a. res#lt $n e&ess$ve tooth -ear or )a. &a#se 'a)a3e to e$st$n3 restorat$ons The restorat$on o% 3ross loss o% tooth s#*stan&e , as $n th$s ea)ple , $s l$kel. to $nvolve &o)ple an' prolon3e' treat)ent
rw
Figure < 11a and b /
Iproved distribution o# occlusal load
!ver/er#pt$on o% a tooth )a. pla&e $t $n s#&h a pos$t$on that $t *ears the *r#nt o% the loa' on $n$t$al &onta&t or $n ers$ve )ove)ents o% the )an'$*le an' there%ore $t )a. -ell *e s#*e&te' to e&ess$ve %or&e In a''$t$on , -here over/er#pt$on o% a tooth has &reate' an o&&l#sal $nter%eren&e +J, the pat$ent )a. )o'$%. the ha*$t#al )ove)ent patterns o% the )an'$*le $n or'er to avo$' the $nter%er$n3 &onta&t Altho#3h s#&h a )o'$%$&at$on ) a. re'#&e the loa' appl$e' to the tooth , the &han3e' pattern $n a&t$v$t. o% the )an'$*#lar )#slat#re )a. s#*seF#entl. pro'#&e )#slar '.s%#n&t$on
=rom the foregoing e*amples it ill be appre.iated that if e*pe.ted to retain their remaining natural teeth for a .onsider tooth loss is restored in suffi.ient time to prevent tooth able number of years) thus alloing the !" to be regarded as a movement ) or to avoid e*.essive stress being pla.ed on the long$term restoration 9 :ut e should remember those patients remaining stru.tures) the subsequent health of the oral tissues hose remaining teeth .arr y a relatively poor prognosis and for .an benefit .onsiderabl y9 ;oever) the point should be made hom) in due .ourse) .omplete dentures are inevitable 9 I% simple that severe damage to the e*isting stru.tures is not an inevitable a.r yli. !"s are provided) the patient is able to serve a pros .onsequen.e of tooth loss9 The impli.ations of this statement theti.
Figure < 12 /
Preparation #or coplete dentures
The lo&at$on o% the re)a$n$n3 teeth pla.s an $)portant part $n the s#&&ess o% s#&h a trans$t$onal 'ent#re It $s &o))on %or the s$ )an'$*#lar anter$or teeth to *e the last re)a$n$n3 teeth $n the )an'$*le A 'ent #re restor$n3 the p oster$or teeth $s %reF #entl. not -orn *. the pat$ent %or the %ollo-$n3 reasons $rstl., the 'ent#re )a. *e #nsta*le *e&a#se there $s l$ttle res$stan&e to $ts '$spla&e)ent $n a poster$or '$re&t$on se&on'l. , there $s ver. l$ttle )ot$vat$on to -ear the 'ent#re as the anter$or teeth are st$ll present
"
#$e removable partial denture euation Figure 29 13 /
Preparation #or coplete dentures
I% , $nstea' o% etra&t$n3 all the teeth , the &an$nes are reta$ne', the 'ent#re -$ll *e )ore sta*le (hen the 'ent#re repla&es anter$or teeth $t $s ver. )#&h )ore l$kel. to *e -orn an' th#s the pat$ent $s l$kel. to 3a$n 3reater *ene%$t %ro) the trans$t$onal 'ent#re
Figure < 14 /
Preparation #or coplete dentures
It sho#l' *e re)e)*ere' that the trans$t$onal RPD $s *e$n3 pla&e' $n a )o#th -here e$st$n3 'ental '$sease $s onl. poorl. &ontrolle' or $s #n&ontrolle' As -$ll *e seen $n the net se&t$on , the ver. presen&e o% a 'ent#re a33ravates the s$t#at$on I% the )o#th $s not $nspe&te' re3#larl. to $'ent$%. treat)ent nee's as the. ar$se, there $s the l$kel$hoo' o% a&&elerat$on o% t$ss#e 'a)a3e, -h$&h )a. pre#'$&e the event#al &o)plete 'ent#re %o#n'at$on In th$s &ase the $n%la))at$on an' h.perplas$a o% the palatal )#&osa -as so severe that s#r3er. ha' to *e per%or)e' *e%ore %#rther prosthet$& treat)ent &o#l' *e #n'ertaken
auses of damage related to t$e *earing of 'Ps earing !"s) su.h as .aries and periodontal disease) .an ;armful effe.ts .an arise from the earing of !"s in a variety be avoided9 ;oever) frequent te.hni.al maintenan.e of !"s is of ays9 =rom the plaque hi.h is li5ely to a..umulate around any still required if optimal oral fun.tion and health are to be !"B from dire.t trauma by individual .omponents of the den preserved9 hen tissue damage does o..ur it is sometimes referred to as tureB from e*.essive fun.tional for.es hi.h ill be transmitted the
D$re&t tra#)a %ro) &o)ponents
A*ras$on an' %ra&t#re o% teeth or restorat$ons
t$ss#es Pro3ress$on to #n'erl.$n3 str#&t#res In%la))at$on o% 3$n3$val t$ss#es Pro3ress$on to #n'erl.$n3 str#&t#res
Trans)$ss$on o% e&ess$ve %#n&t$onal %or&es
+aTooth )o*$l$t. +*A33ravat$on o% e$st$n3 per$o'ontal '$sease
!&&l#sal error
+&Tooth )o*$l$t. +'A33ravat$on o% e$st$n3 per$o'ontal '$sease
+dentulous areas mastication
,uscles of
In%la))at$on o% )#&o#s )e)*rane
Lo&al$se' $n%la))at$on o% )#&o#s )e)*rane Dent#re/ $n'#&e' h.perplas$a
In%la))at$on o% )#&o#s )e)*rane Resorpt$on o% *one In%la))at$on o% )#&o#s '.s%#n&t$on )e)*rane Resorpt$on o% *one
M#s&le
#
A clinical guide to removable partial dentures Increased plaque accumulation - .onsiderable amount of resear.h effort has been dire.ted affe.ts the quantity9 Not only does more plaque a..umulate toards an understanding of the relationship beteen around the teeth in the 6a in hi.h the denture is pla.ed) but plaque a..umulation and the earing of !"s9 I t is possible that also more is found around the teeth in the opposing 6a the pres en.e of a denture influen.es the quality of the plaqueB it unless the patient is instru.ted in meti.ulous oral hygiene .ertainly pro.edures9
Figure 2 . 1%a and b /
Increased pla&ue accuulation
The areas that ten' to &olle&t )ost plaF#e are the pro$)al s#r%a&es o% a*#t)ent tee th a'a&ent to the sa''le +a These s#r%a&es are '$%%$lt to &lean -hen #s$n3 a &onvent$onal tooth*r#sh +* An $nter'ental *r#sh &leans the pro$)al s#r%a&es )ore e%%e&t$vel.
Figure 2. 16a and b /
Increased pla&ue accuulation
The 'es$3n o% the 'ent#re )a. have a s$3n$%$&ant e%%e&t on plaF#e a&)#lat$on or ea)ple , $t has *een sho-n that )ore plaF#e &olle&ts #n'er a l$n3#al plate than #n'er a l$n3#al *ar +a The l$n3#al plate $s -ell s#pporte' on the nat#ral teeth an' %$ts -ell a3a$nst tooth s#r%a&es +* Ho-ever , 3$n3$val $n%la))at$on has *een &a#se' *. the $n&rease' a&)#lat$on o% plaF#e
Figure 2. 1! /
Increased pla&ue accuulation
I% the plaF#e $s allo-e' to pers$st , the $n%la))ator. pro &ess -$ll pro3ress to the 'eeper t$ss#es , res#lt$n3 $n a &hron$& per$o'ont$t$s The per$o'ontal atta&h)ent $s pro3ress$vel. 'estro.e', a per$o'ontal po&ket 'evelops an' the $nvest$n3 alveolar *one $s lost
10
#$e removable partial denture euation Figure < 1" /
Increased pla&ue accuulation
Unless the $n&rease' a&)#lat$on o% plaF#e $s prevente' , root &ar$es $s l$kel. Th$s $s a pro*le) that -$ll $n&rease as )ore pat$ents &ont$n#e to -ear RPDs $nto ol' a3e Root &ar$es $s stron3l. asso&$ate' -$th 3$n3$val re&ess$on an' the #se o% 3$n3$vall./ approa&h$n3 &lasps $n pat$ents -ho are at r$sk *e&a#se o% a &ar$o3en$& '$et an' poor plaF#e &ontrol
Figure < 1( /
Increased pla&ue accuulation
I% plaF#e $s allo-e' to pers$st on the 'ent#re $)press$on s#r%a&e , a 3eneral$se' $n%la))at$on , &alle' 'ent#re sto)at$t$s , )a. o&r T.p$&all. the etent o% the $n%la))at$on $s 'e)ar&ate' *. the o#tl$ne o% the palatal &onne&tor Th$s &on'$t$on $s '$ssse' )ore %#ll. $n Chapter /09
Figure 2.2$a and b -
'irect traua #ro coponents
The oral )#&osa $s v#lnera*le to '$re&t tra#)a %ro) &o)ponents o% 'ent#res +a In th$s $nstan&e the l$n3#al *ar has *een pos$t$one' too &lose to the 3$n3$val )ar3$n The &ont$n#o#s &lasp o%%ers onl. l$)$te' tooth s#pport %or the 'ent#re +* The 'ent#re has s#nk $nto the t$ss#es, str$pp$n3 a-a. the 3$n3$val t$ss#es on the '$stal an' l$n3#al aspe&ts o% >> e
There $s no ev$'en&e %or the &ontent$on that a &lasp ar) )a. -ear a-a. the ena)el s#r%a&e to a 'e3ree that $s s$3n$%$&ant &l$n$&all. Ho-ever , the )ove)ent o% a &lasp ar) )a. -ear the s#r%a&e o% restorat$ve )ater$als
Transmission of excessive force =un.tional for.es are transmitted by an !" to the tissues ith hi.h it is in .onta.t9 I % a denture is supported primarily by the natural teeth most of the for.es ill be transmitted to the alveo lar bone through the fibres of the periodontal ligament9 :earing in mind the orientation of most of these fibres) it ill be
appre.iated that the for.es are tensile in nature and are dissi pated over a relatively large area9 - very different state of affairs e*ists hen a denture is supported only by the mu.osa9 ;ere the for.es) largely .ompressive in nature) are transmitted over a more restri.ted area9
11
A clinical guide to removable partial dentures
Figure 2.21a and b -
)ransission o# e*cessive #orce
I% the %or&es trans)$tte' to the )#&osa an' *one o% the e'ent#lo#s area are e&ess$ve, the )#&osa -$ll *e&o)e $n%la)e' an' the *one -$ll resor* The o*v$o#s &onseF#en&e o% *one resorpt$on $s an $rrevers$*le loss o% part o% the 'ent#re %o#n'at$on +a In th$s ea)ple the 'ent#re $s s#pporte' onl. on the t$ss#es o% the e'ent#lo#s area It has &a#se' resorpt$on o% the *one to s#&h an etent that the l$n3#al *ar &onne&tor has *een p#she' 'o-n to-ar's the %loor o% the )o#th +* The a)o#nt o% *one that has *een 'estro.e' $s apparent -hen the 'ent#re $s re)ove'
Figure 2 .22 - )ransission o# e*cessive #orce I% the 'es$3n o% the 'ent#re $s s#&h that $t trans)$ts e&ess$ve %or&e to a tooth there $s ever. &han&e that the tooth -$ll *e&o)e )o*$le In th$s ea)ple the $n&orre&tl. 'es$3ne' &$n3#l#) rest +5 trans)$ts a hor$ontal %or&e to the &an$ne tooth S#&h hor$ontal %or&es are espe&$all. 'a)a3$n3 to the per$o'ontal t$ss#es The $n&$sal rest +< trans)$ts a )ore %avo#ra*le vert$&al loa' (here per$o'ontal &han3es are restr$&te' to the )ar3$nal 3$n3$vae, el$)$nat$on o% e&ess$ve %or&e -$ll #s#all. allo- the per$o'ontal atta&h)ent to ret#rn to a nor)al health. state (here the s#pport$n3 str#&t#res have *een a%%e&te' *. per$o'ontal '$sease there $s #nl$kel. to *e &o)plete resol#t$on
1
$
3
I 1
2
G
Figure 2.23 -
+cclusal error
I% the o&&l#sal s#r%a&e o% the RP! $s not 'es$3ne' &orre&tl. , nor)al a- &los#re )a. *e prevente' *. a pre)at#re o&&l#sal &onta&t There are three poss$*le seF#elae +5 I% the pre)at#re &onta&t $s on a nat#ral tooth , 'a)a3e to the tooth or $ts per$o'ontal l$3a)ent )a. o&r +< I% the sa''le *ears the *r#nt o% the %or&e o% &los#re , there -$ll *e lo&al$se' )#&osaI $n%la))at$on an' resorpt$on o% the #n'erl.$n3 *one +> I% the pat$ent atte)pts to steer the )an'$*le aro#n' the pre)at#re &onta&t #nt$l a )ore &o)%orta*le o&&l#sal pos$t$on $s %o#n' , th$s a*nor)al &los$n3 pattern thro-s $n&rease' 'e)an's on &erta$n )#s&les o% )ast$&at$on , -h$&h )a. res#lt $n the pat$ent &o)pla$n$n3 o% %a&$al pa$n 1-
#$e removable partial denture euation &alancing t$e 'P" euation - number oflongitudinal .lini.al studies of !"s have shon that the types of damage itemised in the last se.tion may be .ommonly found amongst earers of !"s9 f .onsiderable .on.ern are reports that many patients e*pressed satisfa.tion ith their dentures) in spite of the fa.t that dental health had deteriorated mar5edly9 !erhaps this finding is not altogether surprising hen e remember the insidious nature of the pro gression of .aries and periodontal disease9
Figure 2.24a and b -
ith greater understanding of the relationship beteen plaque and dental disease and of the importan.e of plaque .on trol) reports have appeared hose findings ma5e for more en.ouraging reading9 There is no firm eviden.e that the ear ing of !"s .an be .ompatible ith .ontinued oral health9 This satisfa.tory out.ome depends upon a three$man effort) that of the .lini.ian) the dental te.hni.ian and the patient9
,ontribution o# the clinician
The pr$)ar. respons$*$l$t. o% the 'ent$st an' the &l$n$&al tea) $s to ens#re that the re)a$n$n3 teeth an' s#pport$n3 t$ss#es are restore' to a health. state an' that the pat$ent $s e%%e&t$vel. )ot$vate' an' $nstr#&te' $n ho- to )a$nta$n th$s state +a Th$s )o#th $s not $n a %$t state to re&e$ve an RP! There $s &hron$& per$o'ontal '$sease a n' a&)#lat$on o% plaF#e +* Th$s pat$ent has re spon'e' -ell to $nstr#&t$on $n oral h .3$ene an' the per$o'ontal t$ss#es are health. The 'an3ers o% -ear$n3 the RPDs are th#s )$n$)$se'
The se.ond area of responsibility of the .lini.ian is in relation to the design and .onstru.tion of the denture9 -..ura.y of the .lini.al pro.edures must) of .ourse) be ensured9 In addition) the .lini.ian should produ.e a design based on .riteria that have been shon to promote .ontinued oral health( F @ffe.tive support 9
Figure < 2% /
F learan.e of gingival margins9 F 1impli.ity9 F igid .onne.tor9 These .riteria are .onsidered in greater detail in A Clinical Guide to Removable Partial Denture Design.
,ontribution o# the dental technician
The 'ental te&hn$&$an 2s &ontr$*#t$on $s '$re&te' to-ar's the &are%#l translat$on o% the pres&r$*e' 'ent#re 'es$3n $nto the 'ent#re $tsel%, an' a&rate &onstr#&t$on an' pos$t$on$n3 o% the 'ent#re &o)ponents In th$s $nstan&e the $na&rate %$t -$ll en&o#ra3e plaF#e %or) at$on -$th &onseF#ent per$o'ontal '$sease an' &ar$es , th#s $ntro'#&$n3 an #nne&essar. an' avo$'a*le r$sk to oral health
13
A clinical guide to removable partial dentures Figure 2.26 /
,ontribution o# the patient
It $s pro*a*l. tr#e to sa. that a pat$ent -ho )a$nta$ns $))alate plaF#e &ontrol an' has a 3oo ' t$ss#e res$stan&e, or 2host response 2, &an *e prov$'e' -$th a less than sat$s%a&tor$l. 'es$3ne' 'ent#re an' st$ll )a$nta$n 3oo' oral health S#&h $s the $)portan&e o% pat$ent %a&tors $n the RP! eF#at$on Th$s pat$ent has -orn a ) a$llar. RP! %or )an. .ears The 3$n3$val t$ss#es are health. an' the teeth are -ell s#pporte' *. *one all th$s $n sp$te o% t he %a&t that there $s l$ttle opport#n$t. to prov$'e tooth s#pport
=or every patient) hen a denture is .ontemplated) it is the dentist
disadvantage it is li5ely that it ill be in the patient
- v Figure 2.2!a and b -
,ontribution o# the patient
In th$s )o#th the reasons %or prov$'$n3 'ent#res are not over-hel)$n3 There are s#%%$&$ent teeth at the %ront o% the )o#th to sat$s%. the 'e)an's o% appearan&e an' spee&h There are &erta$nl. eno#3h teeth to allo- a var$e' '$et to *e eaten Most o% the teeth have anta3on$sts $n the oppos$n3 ar&h I% the )o#th $s -ell &are' %or an' the pat$ent reF#ests 'ent#res , the RP! eF#at$on $s %avo#ra*l. *alan&e' Ho-ever , $% plaF#e &ontrol $s s#spe&t , there $s a stron3 ar3#)ent %or a'v$s$n3 a3a$nst 'ent#res , at least %or a %e- )onths #nt$l the lon3/ter) response to oral h.3$ene a'v$&e $s as&erta$ne'
1
,anagement options for t$e partially dentate patient The .on.ept maintains that in partially dentate) middle $aged and elderly adults 7or in younger patients hose posterior teeth have a poor prognosis 8) it is not ne.essar y) or even desirable) to edentulous spa.es .an be .onsidered9 These are( adopt the tr a ditional approa.h of attempting to maintain No treatment9 or fully restore all partial dentitions9 ;en.e) missing teeth only Modifying the edentulous spa.es by orthodonti. tooth movement9 need to be repla.ed if their absen.e is a.tually .ausing estoring the edentulous spa.es by means of fi*ed prostheses problems9 !rior ity teeth for preservation are those that are 7=!s8 or removable partial dentures 7!"s8 ith or ithout .onsidered ation
0
nee a thorough assessment of a partially dentate patient has been underta5en) the management options for the
General factors Figure 3. 1 /
Pschological #a,tors
Ne3at$ve att$t#'es to-ar's RPDs are F#$te &o))on , espe&$all. $n so&$al an' a3e 3ro#ps -here the -ear$n3 o% RPDs $s #n#s#al s#&h 3ro#ps ten' to %avo#r %$e' prostheses +Ps It has *een s#33este' that th$s ne3at$ve att$t#'e, -h$&h $s *ase' pr$)ar$l. on the lo-er $nherent retent$on an' sta*$l$t. o% RPDs , $s o% a s$)$lar nat#re to the so &alle' 2%ear o% 'e)ask$n3 2 that e$sts $n $n'$v$'#als -ear$n3 eternal art$%$&$al *o'. parts s#&h as -$3s an' *reast prost heses
1/
A clinical guide to removable partial dentures esthetic factors :oth =!s and !"s may h ave aestheti. advantage s9 h en abutment teeth e*hibit ma 6or damage to .oronal stru.tur e) eg from severe dental .aries or tr a uma ) ther e ar e often aesth eti.
advant ages for =!s as the damaged ab utment teeth ar e r estor ed ith venee r .rons9
Figure 3.2 - Aesthetic #actors In th$s &ase an P repla&es the )$ss$n3 < < -$th a &ro-n on the a'a&ent <> res#lt$n3 $n a 3oo' o verall appearan&e
Figure 3.3 -
Aesthetic #actors
!ne o% the l$)$t$n3 %a&tors %or %$e' restorat$ons , ho-ever , $s the etent o% alveolar resorpt$on $n the e'ent#lo#s area or pat$ents -here a s$3n$%$&ant a)o#nt o% resorpt$on has o&rre' , there $s o%ten an a'vanta3e $n #t$l$$n3 an RP! *e&a#se the )$ss$n3 alveolar *one &an *e rea'$l. repla&e' *. the 'ent#re *ase / $n th$s &ase *. the a''$t$on o% a la*$al %lan3e
Figure 3.4 / Aesthetic #actors
2
I
Prov$'$n3 a la*$al %lan3e %or an P $s not $'eal *e&a#se $t )akes plaF#e re)oval %ro) aro#n' the restorat$on '$%%$lt Ho-ever , $% a %lan3e $s not e)plo.e' $t &an *e '$%%$lt to a&h$eve a 3oo' appearan&e or ea)ple , here the &l$n$&al &ro-n len3th o% the pant$es has ha' to *e $n&rease' to allo- the) to &onta&t the r$'3e Alternat $ve )etho 's o% repla& $n3 )$ss$ n3 alv eolar *one +e 3 re)ova*le 3$n3$val veneers , *one 3ra%ts %#rther &o)pl$&ate treat)ent
Figure 3.% - Aesthetic #actors or pat$ents -$th )#lt$ple e'ent#lo#s spa&es that reF#$re restorat$on an RP! $s l$kel. to *e the )ost appropr$ate opt$on
1
,anagement options for t$e partially dentate patient dvantages of fixed prostheses o/ incidence o# coplications The reported .lini.al .ompli.ation frequen.ies are loer for =!s than !"s9 This is due to( :etter patient a..eptan.e and toleran.e of the fi*ed restora tion be.ause its dimensions are similar to the original anatomy of the repla.ed teethB =!s interfere less ith plaque removal) thus the oral diseases that .aused the original tooth loss are less li5ely to progress9 !" earers ho are .ooperative .an also prevent the pro gression of oral disease9 There remains hoever ) the need for frequent te.hni.al ad6ustment and repair of the prosthesis 9 -gainst this) it has to be re.ognised that if the maintenan.e of fi*ed restorations is less than meti.ulous ) the potential for dam age to the abutment teeth .an be .onsiderable ) leading to possi ble failure of the =!9
Service li#e The median life of .onventional 7non$adhesive 8 =!s has been re ported to be in the region of 20 years) hereas !"s generally have a median servi.e life of around /0 years9 The so$ .alled adhe$ ive =!s .an be an alternative to !"s for patients ith small edentulous spa.es primarily in the anterior region9 These restora tions have the attra.tion of requiring minimal tooth preparation) but they may have a shorter servi.e life be.ause of their relatively poor retention9 ;oever) adhesive prostheses .an be useful long ter m temporary restorations in .ases here the .onsequen.es of healing need to be evaluated) eg after bone grafting andKor instal lation of implant fi*tures9 :e.ause of their inherent biome.han i.al problems and negative impa.t on oral hygiene pro.edures adhesive =!s should be avoided( EIn areas of high lo.al o..lusal stress) eg in patients ith deep overbitesB In patients ith a.tive plaque related diseases9 dvantages of !P"s Avoidance o# a0or abutent tooth odi#ications - .lear advantage of !"s is that the abutment teeth are li5el y to require only relatively minor ad6ustments to their .o ntour9 These ad6ustments may in.lude the preparation of o..lusal rest eats) guide surfa.es or the modifi.ation of survey lines9 )reatent o# e*tensive tooth loss =or patients ho have suffered e*tensive tooth loss) parti.ularly here the missing teeth in.lude entire premolar and molar seg ments) !"s ith distal e*tension saddles have a better progno$ is than =!s in.orporating .antilevered ponti.s9 This is parti.ularly true if the abutment teeth have good alveolar bone Eu ppo rt9 The resulting high stability of these teeth in fun.t ion .an lead to de.ementation of an =!9 =!s are also at an in.reased r is5 if the abutment teeth have undergone endodonti. treatment as these teeth are then more li5ely to fra.ture9 n the other hand) .ross$ar.h fi*ed restorations ith .an$
tilevered panties have been used su..essfully in the treatment of patients ith mar5edly redu.ed alveolar bone suppor t for the remaining dentition9 The in.reased mobility of the teeth in fun. tion redu.es the .han.e of de.ementation of the prosthesis 9 In su.h .ases !"s are best avoided be.ause of failure to provide any splinting) and be.ause several studies have reported high me.hani.al failure rates for su.h prostheses9
elines ad0ustents and repairs -lthough !"s are usually asso.iated ith more frequent te.h ni.al .ompli.ations than =!s) the ne.essary ad6ustments and repairs are mu.h easier to .arry out9 Initial costs The initial .ost of !"s is almost alays loer than that of =!s9 This does not ne.essarily mean) hoever) that !"s are better long$term finan.ial investments than =!s9 The true .osts of the former may be in.reased by the need for more frequent mainte nan.e and repla.ement of the dentures and remaining teeth9 Suar o# the advantages and disadvantages o# P's copared /ith FPs. -dvantages F Non $invasive $ do not require e*tensive modifi.at ion of abutment teeth9 F Versatile $ are appli.able to a ide variety of .lini.al situa$ tions9 F Leep treatment options open9 F 1uitable for young patients) eg hypodontia9 F an restore long spans be.ause they .an re.ruit mu.osal support to supplement tooth support9 F estoration is more easily and .ompletely a..omplished in the absen.e of a posterior abutment tooth9 -lveolar bone loss .an be restored effe.tively by the denture base9 F emovable to assist .leaning 7of denture and abutment teeth 89 F emovable for .onta.t sports9 elatively tolerant of parafun.tion provided the !" is designed to minimi >e o..lusal stresses and distribute them as idely as possible9 F ess operator$ and te.hnique$sensitive 9 F 1horter .lini.al appointments9 F apable of modifi.ation to .ope ith progressive tooth loss and bone resorption 9 F 1impler but more frequent maintenan.e 9 F ess e*pensive) at least initially9 "isadvantages ess retention and stability9 In.reased plaque Kdebris .olle.tion 7not so streamlined8 9 F !atient may find them less a..eptable9 Intoleran.e of ma6or .onne.tor may o..ur 9 F -ppearan.e of .lasps .an be poor9
1
A clinical guide to removable partial dentures Attac$ments Figure 3.6 / Attachents Atta&h )ents hav e tra'$t $onall. pla.e' an $ )port ant role $n a'v an&e' RP! treat)ents The. 3enerall. o%%er an $nter)e'$ate level o% retent$on *et-een %$e' an' &lasp/reta$ne' prostheses Aesthet$& res#lts are *etter s$n&e &lasps are not reF#$re' The $ntent$on o% an atta&h)ent $s to prov$'e sere &onne&t$on $n %#n&t$on *et-een t-o or )ore prosthet$& &o)ponents, e3 an RP! an' &ro-ns , -h$lst per)$tt$n3 re)oval o% the RP! to allo- &lean$n3 an' )a$ntenan&e To a&h$eve th$s propert., as s#33este' *. the$r na)e , atta&h)ents have one pre&$se '$re&t$on o% $nsert$on , o%ten $n &o)*$nat$on -$th a &o)ple 3eo)etr.
The disadvantages of atta.hments are( The ab utment teeth usually have to be .roned9 In some instan.es) hoever) an adhesive retainer .an be used to bond the atta.hment to the toothB F They usually require a minimum .ron height of about % mmB F The retentive .omponents earB F They are relatively e*pensive9
Figures 3. ' and 3." /
- very ide range of atta.hments has been des.ribed in the lit erature9 =rom a fundamental point of vie) they .an be .lassified into groups of ma.ro$ and mi.ro $atta.hments9 -n alternative .lassifi.ation of atta.hments is based on their fun.tional .hara. teristi.s 7rigidKmovable 89
Macro-attachents
Ma&ro/atta&h)ents $n&l#'e var$o#s t.pes o% teles&op$& &ro-n The. have a &$r)%erent$al 3r$p on the a*#t)ent teeth an' $n&l#'e $n'$v$'#al &$r)%erent$al %ra)e-orks In $3#re >@ 3ol' th$)*les have *een pla&e' on the prepare' #pper anter$or teeth to s#pport an RP! An ea)ple o% s#&h a prosthes$s $n&orporat$n3 teles&op$& &ro-ns $s sho-n $n $3#re >8
Figure 3.9 -
Micro-attachents
M$&ro/atta&h)ents are lo&ate' e$ther on the )es$al or '$stal s#r%a&e o% the a*#t)ent tooth an' )a. *e pla&e' $ntra/ or etra/&oronall. The )$&ro/atta&h)ents '$stall. $n <: an' )es$all. $n the 3ol' &ro-n are $ntra/&oronal
12
,anagement options for t$e partially dentate patient Figure 3. 1$ /
Micro-attachents
Th$s ea)ple o% a )$&ro/atta&h)ent $s lo&ate' etra /&oronall.
s
t
'
Figure 3.11 - igid attachents R$3$' atta&h)ents are tr#e pre&$s$on atta&h)ents *e&a#se the. onl. allo- )ove)ent $n one '$re&t$on S#&h atta&h)ents sho#l' onl. *e #se' $n RPDs that are totall. tooth/s#pporte' In th$s ea)ple the r$3$' atta&h)ent $s sho-n part$all. seate' -$th$n the restorat$on on the pr e)olar a*#t)ent tooth
F igure 3 12 /
Movable attachents
The a$) o% )ova*le &onne&t$ons +*et-een nat#ral teeth an' RPDs $s to &o)pensate %or the %#n'a)ental *$o)e&han$&al '$%%eren&es *et-een teeth an' the oral )#&osa $n or'er to '$str$*#te %#n&t$onal loa' to the e'ent#lo#s alveolar r$'3e as -ell as to the re)a $n$n3 'ent$t$on There $s l$ttle ev$'en&e that th$s %#n&t$onal '$str$*#t$on o% loa' o&rs $n a &ontrolle' %ash$on as planne' Mova*le atta&h)ents have var.$n3 'e3rees o% %ree'o) o% )ove)ent ran3$n3 %ro) that o% a s$)ple h $n3e to )ore &o)ple 3eo)etr$& &on%$3#rat$ons In th$s ea)ple the spher$&al etens$on '$stall. on the a*#t)ent tooth $s 'es$3ne' to en3a3e an atta&h)ent -$th$n the RP! an' allo- the sa''le to rotate to-ar's the )#&osa -hen loa'e' '#r$n3 %#n&t$on
!mplants o%
Figure 3. 13 $ Iplants In r e&ent .ears !sseo/$nte3rate' $)plant/s#pporte' prostheses have *een $ntro'#&e' as alternat$ves to &onvent$onal Ps an' RPDs %or the r epla&e)ent o% teeth $n part$all. 'entate s#*e&ts Ho-ever , s#r3er. $s al-a.s reF#$re' %or the pla&e)ent o% $)plants an' )a. *e &o)pl$&ate' *. the pro$)$t. o% the ne#ro/ vaslar *#n'le or )a $llar. s$n#s Also , la&k o% alveolar *one vol#)e $s part$larl. '$sa'vanta3eo#s In a''$t$on , $)plants are epens$ve an' there $s a ran3e o% )e'$ &al &ontra$n'$&at$ons to th$s %or) o% treat)ent , $n&l#'$n3 heav. s)ok$n3 or these reasons $t $s #nl$kel. that $)plants -$ll s$3n$%$&antl. re'#&e the nee' %or RPDs $n the %oreseea*le %#t#re
=i*ed super stru.tures ar e generally pref er r ed for partially den tate patients ith multiple implants as they provide more stable for .e tran sf er patterns to the surrounding bone than !"s9 This
is desir a ble be.ause osseo$integrated implants are rigidly retained in the bone 7li5e an an.hylosed tooth 8 and ar e ther efore more sus.eptibl e to non $a*ial loading than natural teeth9 1
'Ps and t$e elderly
eople are living longer and retaining more of their teeth into old age9 This trend is li5ely to .ontinue as the .urrent
older age groups ere more negatively in.lined toards the ear ing of !"s than younger individuals9 I t as as if the longer a person had managed to fun.tion adequately ithout an !") the middle $aged population) tomorro
P
4pecific problems of t$e elderly in relation to t$e provision of 'Ps Figure 4. 1 /
)ooth /ea r
Tooth -ear $s an $n&reas$n3l. &o))on %$n'$n3 , part$larl. $n ol'er pat$ents The $n$t$at$n3 %a&tor ) a. *e attr$t$on , a*ras$on or eros$on , an' $n )ore a'van&e' -ear a &o)*$nat$on o% these a3ents )a. *e $nvolve' It $s $)portant to esta*l$sh a '$a3nos$s $% poss$*le an' $nst$t#te )eas#res to el$)$nate an. &a#sat$ve %a&tors , th#s prevent$n3 %#rther 'a)a3e to the 'ent$t$on
There is some eviden.e that in those patients ho are sus.ep tible to tooth ear) the problem may be more severe if the denti tion is depleted and fun.tional loading is .on.entrated on a small number of .onta.ting teeth 9 I % it is evident that t ooth loss has .re ated a defi.ien.y $n o..lusal support) the provision of !"s may help to stabilise the situation and prevent further deterioration 9 !atients ill often see5 treatment be.ause they are unhappy
ith the appearan.e of orn teeth in the anterior region of the mouth9 hen the ear is moderate in e*tent) the teeth may be either maintained or restored ith .rons and !"s in order to stabilise the o..lusal relationship and repla.e missing teeth 9 hen ear is more severe) overlays may be in.orporated in the denture design to provide a satisfa.tor y aestheti. and fun.tional result9
2/
A clinical guide to removable partial dentures Figure 4.2 /
)ooth /ear
In etre)e &ases $t )a. *e )ore appropr$ate to &ons$'er the re'#&t$on o% so)e teeth to serve as over'ent#re a*#t)ents Root a*#t)ents &an )ake a s#*stant$al &ontr$*#t$on to the s#pport o% RPDs , part$larl. -hen the alternat$ve -o#l' *e an e'ent#lo#s sa''le area oppose' *. a s#*stant$al 3ro#p o% nat#ral teeth
Figure 4.3 -
oot sur#ace caries
Re%eren&e has prev$o#sl. *e en )a'e to the ten'en&. %or RPDs to en&o#ra3e the a&)#lat$on o% plaF#e Th$s %a&tor *e&o)es part$larl. $)portant $n ol'er pat$ents as 3$n3$val re&ess$on )a. lea' to the e pos#re o% root str#&t#re an' an $n&rease' r$sk o% root s#r%a&e &ar$es The s$t#at$on -$ll *e a33ravate' %#rther $% the a*$l$t. to )a$nta$n a'eF#ate plaF#e &ontrol *e&o)es $)pa$re' %or an. reason an' $% the $ntake o% %er)enta*le &ar*oh.'rate $n&reases as taste sens$t$v$t. 'e&l$nes an' )ast$&ator. e%%$&$en&. '$)$n$shes It $s there%ore part$larl. $)portant to ens#re that 'ent#res are 'es$3ne' to )$n$)$se &onta&t -$th , or &overa3e o% , v#lnera*le areas or ea)ple , 3$n3$vall. approa&h$n3 &lasps -h$&h &ross an' &onta&t the epose' root s#r%a&e sho#l' onl. *e #se' $% a &are%#l eval#at$on $n'$&ates that the r$sk to a part$lar pat$ent $s $ns$3n$%$&ant
Patient assessment General health status -ge by itself is an impre.ise guideline in the assessment of older patient
'Ps and t$e elderly #reatment options =or the older patient) de.isions on hether or not to provide !"s and of balan.ing benefits of a prosthesis against potential
Figure 4.4a and b /
harm to the mouth may ell be more .riti.al than for a younger patient9
)reatent options
I% a shortene' 'ental ar&h e$sts part$lar attent$on )#st *e 3$v en to the poss$*$l$t. o% s$)pl. )a$nta$n$n3 the stat#s F#o rather than prov$'$n3 an RP!
Figure 4.: /
)reatent options
In th$s ea)ple the pat$ent ha' no -orr$es a*o#t appearan&e *#t ha' eper$en&e' '$%%$lt$es $n eat$n3 B. prov$'$n3 a )an'$*#lar RP! to $)prove )ast$&ator. a*$l$t., treat)ent that )et the pat$ent 2s spe&$%$& &on&erns , $t -as poss$*le to avo$' an RP! $n the )a$llar. ar&h
Figure 4.6 /
)reatent options
( here there has *een etens$ve tooth loss , one o% the )ost $)portant 'e&$s$ons $s -hether or not to reta$n a sele&t$on o% teeth to ass$st -$th the -ear$n3 o% an RP! Even $% $t appears that s#&h an arran3e)ent )a. have a l$)$te' l$%e $t $s #s#all. %ar pre%era*le to etra&t$ons a n' the prov$s$on o% &o)plete 'ent#res In th$s ea)ple the re)a$n$n3 nat#ral teeth helpe' to sta*$l$se )a$llar. an' )an'$*#lar RP!s A%ter a short t$)e t-o o% the )a$llar. teeth an' *oth )an'$*#lar teeth -ere &onverte' to over'ent#re a*#t)ents an' &ont$n#e' to serve the pat$ent % a$th%#ll. %or )an. .ears Th#s an e%%e&t$ve 2pre/e'ent#lo#s2 state -as preserve' Even $% the event#al etra&t$on o% the re)a$n$n3 teeth $s $nev$ta*le , the$r retent$on $n the short ter) to sta*$l$se an RP! &an )ake a s$3n$%$&ant &ontr$*#t$on to a s#&&ess%#l trans$t$on o% a pat$ent to &o)plete 'ent#res
$3
Anatomy of t$e denture6bearing areas In&$s$ve pap$lla
La*$al %ren#)
Res$'#al r$'3 e
B#&&al %ren#)
.3o)at$& *#ttress
R#3ae
K K Palat$ne
K, K 2 K tor#s
Ha)#lar not&h
Palat$ne %ovea
Fi gures % . 1 and % .2 a*illa. Fi g ure %.3 -
La*$al s#ls
B#&&al s#ls
Sur#ace anato o# the
Incisive papilla
Th$s so%t pa' o% t$ss#e overl$es the $n&$s$ve &anal thro#3h -h$&h pass he nerves an' vessels s#ppl.$n3 the anter$or part o% the palatal )#&osa The la*$al s#r%a&es o% the nat#ral &entral $n&$sors l$e appro$)atel. 5!)) anter$or to the &entre o% the pap$lla , a relat$onsh$p that sho#l' *e *orne $n )$n' -hen pos$t$on$n3 the art$%$&$al r epla&e)ents
25
A clinical guide to removable partial dentures Figure %.4 /
ugae
These $rre3#lar transverse )#&osal r$'3es o&r $n the anter$or part o% the har' palate Th$s $s anarea a%%$ne ta&t$le '$s&r$)$nat$on an' RPDs sho#l' there%ore *e 'es$3ne' to leave as )#&h o% th$s area #n&overe' as poss$*le ro) th$s po$nt o% v$e-, the anter$or *or'er o% the 'ent#re sho-n here $s pre%era*le to the *or'er $n'$&ate' *. the 'otte' l$ne
Figure :: 1. Palatine raphe Th$s $s a )#&osal r$' 3e l.$n3 sa3$ttall. $n the )$'l$ne o% the palate
29 Palatine )orus Th$s 'evelop)ental *on. pro)$nen&e $s so)et$)es seen $n the &entre o% the palate Th$s str#&t#re $s o%ten &overe' *. relat$vel. $n&o)press$*le )#&oper$oste#) A )#&osall./s#pporte' 'ent#re )a. nee' to *e rel$eve' over the tor#s to prevent the 'ent#re ro&k$n3 an' %le$n3 a*o#t the )$'l$ne
Figure : 6 /
ibrating line
Th$s $s the #n&t$on *et-een the )ova*le ) #&osa o% the so%t palate an' the stat$& )#&osa o% the har' palate I% a 'e&$s$on has *een taken to o*ta$n )a$)#) poster$or etens$on o% the )aor &onne&tor, the poster$or *or'er o% the &onne&tor sho#l' *e pos$t$one' on the &o)press$*le t$ss#e #st anter$or to the v$*rat$n3 l$ne
Figure #9' 1. Palatine #ovea These are the or$%$&es o% &o))on &olle&t$n3 '#&ts o% )$nor palat$ne sal$var. 3lan's The. present as t-o s)all 'epress$ons $n the )#&osa an' are o%ten to *e %o#n' &lose to the v$*rat$n3 l$ne on e$ther s$ 'e o% the )$'l$ne
v 1
$!
29 aular 5otch Th$s )#& osal 'epress$on $s lo&ate' poster$or to the )a$llar. t#*eros$t. The not&h overl$es the 3ap *et-een the pter.3o$' ha)#l#s an' the )a$llar. t#*eros$t. an' )arks the poster$or l$)$t o% etens$on o% a )a$llar. sa''le -here there $s no '$stal a*#t )ent tooth
Anatomy of t$e denture6bearing areas Figure % ." o% s e'
Palatine subucosa
"ar$at$on $n th$&kness o% the s#*)#&osa $n%l#en&es the &o)press$*$l$t. o% the 'ent#re/*ear$n3 s#r%a&e an' &onseF#entl. the 'e3ree o% )#&osal s#pport o%%ere' to a )a$llar. RP! The alveolar r$'3es an' the &entre o% the palate -$ll #s#all. *e the )ost e%%e&t$ve s#pport areas
M#&oper$oste#)
M#&osa
S#*)#&osa
Bone
The in.lusion of a palatal relief in the !" should be .onsid be a plate ( ibid .hapter ,89 - palatal relief is a spa.e beteen er ed using the folloing .riteria9 I % the .entral palatal area is the .onne.tor and the area of relatively in.ompressible mu.osa noti.eably less .ompressible than that of the ridgesB if the !" .re ated by the te.hni.ian laying don a thin sheet of a* on is to be mu.osa supp orte d (A Clinical Guid e to Removable Par this area before dupli .ating th e .ast prior to a*ing up the tial Denture Design .hapter #8B and if the ma6or .onne.tor is to !" frameor59 e a.
Pear shape' pa'
Retro).loh.o$' area +l$n3#al po#&h
Retro)olar pa'
B#&&al shel%
n'
L$n3#al %ren#)
B#&&al s#ls
B#&&al shel%
B#&&al %ren#)
B#&&al s#ls
La*$al s#ls
La*$al %ren#)
B#&&al %ren#)
La*$al %ren#)
Fi gures : ( and : 1$ /
Sur#ace anato o# the
andible Fi gure % . 11 -
ucca7 shel#
Th$s l$es *et-een the &rest o% the res$'#al r$'3e an' the eternal o*l$F#e r$'3e o% the )an'$*le Its relat$vel. *roa' hor$ontal s#r%a&e &overe' -$th s)ooth &ort$&al *one )akes $t a val#a*le s#pport area %or a )an'$*#lar prosthes$s an' o% part$lar $)portan&e $n the s#pport o% a '$stal etens$on sa''le
e
$t.
27
A clinical guide to removable partial dentures Figure #9 12 /
etroolar and pear-shaped pads
The pear/shape' pa' +5 l$es anter$orl. to the retro)olar pa' +< an' $s the )ost '$stal etens$on o% the atta&he' kerat$n$se' )#&osa overl.$n3 the )an'$*#lar r$'3e It $s %or)e' *. the s&arr$n3 pattern %ollo-$n3 etra&t$on o% the )ost poster$or )olar It $s %$r) an' %$*ro#s an' %or)s an $)portant part o% the 'ent#re/*ear$n3 area It o%%ers s#pport to the 'ent#re an' helps to res$st poster$or '$spla&e)ent The retro)olar pa' $s a %reel. ) ova*le )ass o% t$ss#e &ons$st$n3 o% non/kerat$n$se' )#&osa overl.$n3 loose 3lan'#lar &onne&t$ve t$ss#e It %alls o#ts$'e the 'ent#re/*ear$n3 area In the a*sen&e o% )a$llar. an' )an'$*#la r poster$or teeth , a po$nt *et-een the pear/shape' an' retro)olar pa's )a. *e #se' to 'eter)$ne the level o% the o&&l#sal plane o% the 'ent#re teeth poster$orl.
Figure #9 13 /
M7ohoid ridge
Th$s $s the *on. r$'3e to -h$&h the ).loh.o$' )#s& le $s atta&he' As resorpt$on o% the res$'#al r$'3e pro&ee's , the pro)$nen&e o% the ).loh.o$' r$'3e ten's to $n&rease , pre'$spos$n3 to )#&osa= soreness *eneath the 'ent#re $n th$s area
M.loh.o$' r$'3e an' )#s&le
Figure 5. 14 -
etrolohoid area 8 9lingual pouch:
Th$s area $s the part o% the l$n3#al s#ls l.$n3 *elo- the ).loh.o$' r$'3e poster$orl. (henever the %#n&t$onal )ove)ents o% the s#ls per)$t , the l$n3#al %lan3e o% a '$stal etens$on sa''le sho#l' *e eten'e' $nto th$s area to prov$'e o pt$)#) sta*$l$t.
Figure #9 15 $
Mandibular tori
These tor$ are 'evelop)ental *on. s-ell$n3s o&&as$onall. seen l$n3#all. $n the pre)olar re3$on The. are *$lateral, so)et$)es )#lt$ple an' #s#all. s.))etr$&al Man'$*#lar tor$ )a. prevent opt$)#) pos$t$on$n3 o% a l$n3#al )aor &onne&tor an' $% so )a. nee' to *e re)ove' s#r3$&all.
28
Anatomy of t$e denture6bearing areas Figure #9 16 / IS
1 g
The s#ls $s the )#&osal tro#3h J l.$n3 *et-een the r$'3e on the one han' an' the &heeks , l$ps or ton3#e on the other An a&rate $)press$on o% the %#n&t$onal 'epth an' -$'th o% the s#l&$ $s ne&essar. *e&a#se , $n the )aor$t. o% &ases , the 'ent#re %lan3es -$ll nee' to %$ll the '$)ens$ons o% the s#l&$ so re&or'e' It $s part$larl. $)portant to o*ta$n an a&rate re& or'$n3 o% the %or) o% the l$n3#al s#ls *e&a#se th$s -$ll 'eter)$ne the 'e s$3n an' pos$t$on$n3 o% l$n3#al )aor &onne&tors
F i gure : 1! /
s
Sulcus
Frenu
Th$s %ol' o% )#&o#s )e)*rane &rosses the s#ls an' &onta$ns a %$*ro#s s#*)#&osa *#t no )#s&le %$*res rena o&r *#&&all. $n the pre)olar re3$ons an' also $n the )$'l$ne The. reF#$re s#%%$&$ent &learan&e *. the *or'er o% a 'ent#re to allo- the$r #n$)pe 'e' )ove)ent $n %#n&t$on
F i gure : 1" -
Anato o# the buccal sulci
Anato). o% the *#&&al s#l&$ relate' to the *or'ers o% the )a $llar. an' )an'$*#lar 'ent#res
.3o)at$& pro&ess o% the )a$lla
le
Figure : 1( / Anato o# the lingual sulci Anato). o% the l$n3#al s #l&$ r elate' t o the *or'e r o% t he )an'$*#lar 'ent#re
Gen$o3loss#s )
S#*/l$n3#al sal$var. 3lan'
$#
A clinical guide to removable partial dentures M
LA!
M
IS
DA!
II
II
DA!
Figure #920 $
Madia7us
Th$s $s a 'essat$on o% )#s&le %$*res near the an3le o% the l$ps The )o'$ol#s &an %$ the &orner o% the )o#th $n an. pos$t$on reF#$re' %or %#n&t$on an' '#r$n3 )ast$&at$on $t &loses the *#&&al s#l&$ to prevent es&ape o% the *ol#s o% %oo' B *#&&$nator ) DA! 'epressor an3#l$ or$s ) II $n&$s$v#s $n%er$or ) IS $n&$s$v#s s#per$or ) LA! levator an3#l$ or$s ) or*$lar$s or$s ) 00 M .3o)at$s ) aor )
"ynamic anatomic relationships 1o far in this .hapter e have .on.entrated on the stati. rela tionship of oral stru.tures to !"s9 ;oever ) the dynami. rela tionships also need to be .onsidered9
Figure : 21 /
Masseter and adia7us uscles
!n &len&h$n3 the teeth the anter$or *or'er o% the )asseter )#s&le *#l3es $nto the '$sto*#&&al s#ls area I% the %lan3e o% a 'ent#re $s over/eten'e' $n th$s area the res#lt$n3 press#re )a. lea' to soreness an' '$spla&e)ent o% the 'ent#re S$)$larl. %a$l#re to &onto#r the *#&&al %lan3e o% a )an'$*#lar 'ent#re $n the pre)olar re3$on to a&&o))o'ate the a&t$v$t. o% the )o'$ol#s $s l$kel. to res#lt $n '$spla&e)ent o% the 'ent#re
Figure #922 $
uccinatar uscle
Contra&t$on o% the *#&&$nator )#s&le ra$ses a hor$ontal so%t/t$ss#e *an' at a*o#t the level o% the o&&l#sal plane The pol$she' s#r%a&e o% a *#&&al %lan3e sho# l' *e shape' s o that the press#re %all$n3 on $t %ro) th$s *#&&$nator a&t$v$t. - $ll have a &o)ponent o% %or&e -h$&h $s '$re&te' to-ar's the r$'3e an' -h$&h -$ll there%ore help to reta$n, rather than '$slo'3e , the 'ent#re
Figure % .23 -
Menta7is uscle
Contra&t$on o% the )ental$s )#s&le ra$ses the so%t t$ss#es o% the &h$n, th#s re'#&$n3 the 'epth an' -$'th o% the la*$al s#ls I% there has *een )arke' resorpt$on o% the #n'erl.$n3 *one , th$s )#s&le &an eert &ons$'era*le press#re on the la*$al %lan3e o% an RP! res#lt$n3 $n $ts poster$or an' #p-ar' '$spla&e)ent Care )a. there%ore *e nee'e' $n &onto#r $n3 an' th$nn$n3 the %lan3e to )$n$)$se th$s press#re
30
Anatomy of t$e denture6bearing areas Figure %.24 /
Sub-lingual #olds
(hen the ton3#e $s elevate' , the s#*l$n3#al %ol's are ra$se' an' )a. 3reatl. re'#&e the 'epth an' -$'th o% the l$n3#al s#ls Th$s pheno)enon $s )ost )arke' -hen a'van&e' resorpt$on o% the r$'3e has o&rre'
Figure #92# $
,oronoid process
( hen the )an'$*le $s )ove' laterall. , the &orono$' pro&ess on the non/-ork$n3 s$'e +the s$'e %ro) -h$&h the )an'$*le $s )o v$n3 &o)es $nto &lose relat$onsh$p to the *#&&al aspe&t o% the )a $llar. t#*eros $t. The *#&&al s#ls $n th$s re3$on $s th#s re'#&e' $n - $'th , l$)$t$n3 the spa&e ava$la*le %or a *#&&al %lan3e
31
7a* relations$ips
a relationships may be .onsidered from an anatomi.al and from a fun.tional viepoint) and an understanding of both viepoints is fundament al to the effe.tive restoration of the partially dentate mout h9 The folloing .hapter is .on.erned mainly ith the fun.tional aspe.ts of 6a relationships 9 =or a detailed .onsideration of the anatomi.al and neurophysiologi.al as pe.ts the reader is referred to standard te*tboo5s9 ithin the range of fun.tional relationships beteen mandible
Figure 9 1 /
and ma*illa) it is importa nt t o separate the non$.onta.t rela tionships) hen the teeth are apart) from the .onta.t relation ships) hen the teeth are together 9
Non6contact relations$ips The teeth are apart and the mandible moves entirely under the influen.e of the mus.les of masti.ation and the arti.ular surfa.es of the temporomandibular 6oints 7posterior guidan.e89
5on-contact relationships
Move)ent -$th$n the te)poro)an'$*#lar o$nts &an $nvolve s$)ple rotat$on o% the &on'.le alon3 the retr#'e' ar& o% &los#re o% the )an'$*le Th$s ar&, 'es&r$*e' *. the )an'$*le -h$le the &on'.les are $n the$r )ost poster$or pos$t$on, o&rs over the last <0)) o% &los#re as )eas#re' %ro) the )an'$*#lar )$'/$n&$sal po$nt The a$s o% rotat$on thro#3h the &on'.les $s kno-n as the retr#'e' h$n3e a$s an' $t $s o%ten #se' %or )o#nt$n3 &asts on a'#sta*le art$lators as $t $s repro'#&$*le, *e$n3 #na%%e&te' *. loss o% teeth or &han3es $n the o&&l#sal s#r%a&es o% the teeth
Figure %92 $
5on-contact relationships
Con'.lar )ove)ent $n protr#s$on $nvolves translat$on o% *oth &on'.les %or-ar' an' 'o-n-ar's alon3 the &on'.lar path +5, esta*l$sh$n3 the poster$or 3#$'an&e The &on'.larpath $s 3enerall. relate' to a hor$ontal plane o% re%eren&e, the rank%ort plane +<, -h$&h passes thro#3h the s#per$or )ar3$n o% the eternal a#'$tor. &anal an' the $n%er$or )ar3$n o% the *on. or*$t The an3le +> %or)e' *et-een th$s plane an' the &on'.lar path $s the &on'.lar or sa3$ttal &on'.lar an3le
33
I
&l$n$&al 3#$'e to re)ova*le part$al 'ent#res Figure .3 -
5on-contact relationships
In lateral ers$on, one &on'.le )oves 'o-n-ar's , %or-ar's an' )e'$all. an' the an3le -h$&h $ts path o% )ove)ent )akes -$th the sa3$ttal plane $s kno-n as the Bennett an3le 7/ 89 The other )oves pre'o)$nantl. $n the hor$ontal plane $nvolv$n3 a &o)*$nat$on o% rotat$on an' so)e 'e3ree o% lateral translat$on +Bennett )ove)ent o% the )an'$*le +< The s$'e to-ar's -h$&h the )an'$*le )oves $s 'es&r$*e' as the -ork$n3 s$'e an' the other as the non /-ork$n3 s$'e
Figure 6.4 /
Rest position and #ree/a space
(hen the )#s&les o% )ast$&at$on are relae' there $s #s#all. a spa&e *et-een )a$llar. an' )an'$*#lar teeth Th$s $s &alle' the %ree-a. spa&e or $ntero&&l#sal '$stan&e an' -hen v$e-e' $n the sa3$ttal plane $s -e'3e/shape', -$th a separat$on $n the $n&$sal re3$on , -h$&h $s #s#all. -$th$n the ran3e ;))
ontact relations$ips onta.t beteen the teeth of the opposing dental ar.hes has a moderating influen.e on the basi. pattern of movement of the mandible 7anterior guidan.e89
F i g u r e
% 9 # $ l n t %9 6 / etruded contact position Figure e r $s a &onta&t relat$onsh$p $n -h$&h the )an'$*le $s lo&ate' / $/9# Th$s )) c '$stal to the $nterspal pos$t$on There are 3enerall. %e-er tooth &onta&ts present than $n ICP an' there $s a sl$3htl. 3reater vert $&al u separat$on o% )an'$*le %ro) )a$lla as the &onta&t $s on the slopes s o% the sps I'eall., )ove)ent %ro) retr#'e' &o nta&t to $nterspal p pos$t$on sho#l' *e a %or-ar' sl$'e -$th no lateral 'ev$at$on a l
>;
p o s i t i o
7a* relations$ips Figure 6. ' $ Protrusive relationship or)all., protr#s$on o% the )an'$*le -$ll lea' $n$t$all. to &onta&t o% the a*$al s#r%a&es or $n&$sal e'3es o% the )an'$*#lar anter$or teeth a3a$nst the palatal aspe&t o% the )a$llar. $n&$sors an' event#all. to an e'3e to/e'3e $n&$sal &onta&t Th#s $n th$s earl. sta3e o% protr#s$on, the '$re&t$on o% )an'$*#lar )ove)ent $s 'eter)$ne' *. the palatal slope o% the )a$llar. $n&$sors th$s $s kno-n as $n&$sal 3#$'an&e Co))onl. th$s )ove)ent $s asso&$ate' -$th separat$on o% the poster$or o&&l#sal s#r%a&es (here the n&$sors &o) )en&e $n an e'3e/to/ e'3e relat$onsh$p or -here the )an'$*#lar $n&$sors are $n a'van&e o% the )a$llar. $n&$sors, protr#s$ve 2l love)ent -$ll &arr. the )an'$*#lar $n&$sors %or-ar' o% the )a$llar. teeth, o%ten -$th F#$te -$'esprea' &onta&t o% the poster$or o&&l#sal s#r% a&es
Fi gure 6 ." / e
e $s ll.
2I << <2 22 < <<< G
G
I
,
2G
2
2 ,
G
999999999999 99
ateral e*cursion
% the anter$or 3#$'an&e 'oes not res#lt $n '$s&l#s$ons o% the poster$or eeth '#r$n3 )ove)ent o% the )an'$*le %ro) ICP , the spal $n&l$nes o% ooster$or teeth on the -ork$n3 s$'e $n%l#en&e the path o% lateral ers$on as sho-n here
I
<,
,
2
!
I
<
G
<
G
2
F igure 6 .( -
G
G
ateral e*cursion
n lateral ers$on , there -$ll 3enerall. *e &onta&t o% the oppos$n3 'ent$t$ons on the -ork$n3 s$'e %ollo-$n3 one o% t-o patterns Conta&t )a. *e esta*l$she' al)ost $))e'$atel. *et-een the &an$nes N$th separat$on o% all the other teeth / a s$t#at$on 'es&r$*e' as &an$ne 3#$'an&e
In &t o ar 0
Figure 6 . 1$ /
ateral e*cursion
Alternat$vel., &onta&t )a. *e )a$nta$ne' *et-een a 3ro#p o% teeth, #s#all. &entre' $n the &an$nepre)olar re3$on, -$th 3ra'#al separat$on o% the re)a$n$n3 teeth / a s$t#at$on 'es&r$*e' as 3ro#p %#n&t$on
o%
3%
A clinical guide to removable partial dentures Figure 6.11 -
ateral e*cursion
Generall. there -$ll *e &o)plete separat$on o% the teeth on the non -ork$n3 s$'e an' an. $solate' non/-ork$n3 s$'e &onta&t , s#&h as *et-een 5: an' ;9 , sho#l' *e re3ar'e' as a potent$al o&&l#sal $nter%eren&e '#r$n3 s#&h ers$ve )ove)ents !&&as$onall. there )a. *e *$lateral o&&l#sal *alan&e $ n the nat#ral 'ent$t$on s$)$lar to that 'es&r$*e' $n &o)plete 'ent#re &onstr#&t$on
onta.t movements are thus influen.ed both by posterior guidan.e from the temporomandi bular 6oints and by anterior guidan.e from the teeth9 I t il illl be .lear that it is the .onta.t rela$ rela$
tionships hi.h ill be the determinin g fa.tor in deve developing loping the o..lusal s.heme for most !"s9
Figure 6. 12 /
I I
Masticator ccle
The )ove)ent *et-een the var$o#s &onta&t relat$onsh$ps o% the )an'$*le $s o%ten 'es&r$*e' as &o))en&$n3 $n ICP -$th -$th ers$on o#t to a protr#'e' or lateral pos$t$on Th$s prov$'es a &onven$ent -a. o% 'es&r$*$n3 an' anal.s$n3 )an'$*#lar )ove)ent an' s#&h ers$ons are $n'ee' &hara&ter$st$& o% the para%#n&t$onal 3r$n'$n3 an' r#**$n3 a&t$v$t. o% *r#$s) Ho-ever, $n )ast$&ator. %#n&t$on, %#n&t$on, the )ove)ent )ore o%ten takes pla&e $n the oppos$te '$re&t$on Clos#re thro#3h the *ol#s o% %oo' th#s *r$n3s the )an'$*le %ro) the ers$ve pos$t$on *a&k to the $nterspal pos$t$on
,
< I I
p 0
0 KE
ICP
RCP O Retr#'e' &onta&t pos$t$on RAC O Retr#'e' ar& o% &los#re RP O Rest pos$t$on
Figures 6. 13 13 6. 14 and 6. 1% /
Y ree-a. spa&e U#'3e' to *e the '$stan&e *et-een the rest pos$t$on an' the $nterspal pos$t$on P O Ma$)#) protr#s$on
(S
lnterspal pos$t$on
0 O Ma$)#) open$n3 L O Ma$)#) lateral ers$on /
Conta&t )ove)ents
/
Non/&onta&t )ove)ents
=nvelope o# oveent
A so /&alle ' 2envel ope o% ) ove) ent2 tr a&e' *. the )an'$* #lar )$'/$n &$sal po$nt an' 'es&r$ *e' or$3$n all. * . Posselt , &an represent the total ran3e o% )an'$*#lar )ove)ent Th$s envelope $s sho-n $n the sa3$ttal plane +95>, le%t , $n the &oronal plane +95; , )$''le an' $n the hor$ontal plane +95:, r$3ht
3!
7a* relations$ips Figure 6. 16 /
)ooth contact relationships and P+s
The etent to -h$&h these %eat#res o% the var$o#s tooth &onta&t relat$onsh$ps -$ll $n%l#en&e RP! 'es$3n an' &onstr#&t$on -$ll 'epen' on the n#)*er an' lo&at$on o% the )$ss$n3 teeth ($th )$n$)al tooth loss an' a sta*le $nterspal relat$onsh$p the o&&l#s$on o% the RP! sho#l' har)on$se -$th the e$st$n3 $nterspal relat$onsh$p an' -$th the var$o#s ers$ve 3#$'an&es esta*l$she' *. the re)a$n$n3 teeth
e
s
Figure 6. 1! /
)ooth contact relationships and P+s
(hen loss o% poster$or teeth has el$)$nate' the ent$re poster$or o&&l#sal ta*le $n one or *oth a-s there $s no lon3er an. re&or' o% the $nterspal $n terspal pos$t$on In these &$r)stan&es the hor$ontal arelat$onsh$p sho#l' *e re&or'e' $n the retr#'e' pos$t$on The o&&l#sal v ert$&al relat$onsh$p relat$onsh$p $s 'er$ve' %ro) the rest$n3 vert$&al '$)ens$on a%ter )ak$n3 an allo-an&e %or an appropr$ate %ree-a. spa&e The prosthet$& o&&l#s$on o& &l#s$on $s th#s esta*l$she' $n the retr#'e' a- relat$onsh$p an' the $nterspal $n terspal pos$t$on $s then $'ent$&al -$th -$th the retr#'e' &onta&t pos$t$on Ho-ever, $t -$ll #s#all. *e ne&essar. to eF#$l$*rate the o&&l#s$on to allo- so)e %or-ar' sl$'e to take pla&e
&k
Figure 6. 1" /
)ooth contact relationships and P's
Pro*le)s &an also ar$se -hen tooth loss an' o&&l#sal -ear are s#per$)pose' on an #n'erl.$n3 )alo&&l#s$on Here , the $n$t$al &onta&t ta takes kes pla&e $n the anter$or re3$on an' the o&&l#sal s#r%a&es o% the poster$or teeth are separate' *. at least <))
Figure 6. 1( /
)ooth contact relationships and P's
The )an'$*le has no- *een 3#$'e' %or-ar' $nt o a pos$t$on o% a&&o))o'at$on $n -h$&h there $s &onta&t o% the poster$or teeth an' a reverse $n&$sal over*$te o% a*o#t <)) I% th$s pattern o% o&&l#sal &onta&t $s le%t #n&orre&te' there $s a 'an3er that th at $n'$v$'#al teeth -$ll *e&o)e %#n&t$onall. overloa'e' -$th r$sk o% e& e&ess$ve ess$ve tooth -ear -ear or per$o'ontal per$o'ontal *reak'o-n It $s also poss$*le that th the e pat$ent )a. 'evelop )an'$*#lar '.s%#n&t$on , as $n'ee' happene' $n th$s th $s $nstan&e In these &$r)stan&es $t -$ll -$ll *e ne&essar. to re&or' the retr#'e' a- re relat$onsh$p lat$onsh$p on the retr#'e' ar& o% &los#re , to #n'ertake eF#$l$*rat$on o% th the e teeth an' to prov$'e a )an'$*#lar RP! -$th o&&l#sal overla.s to esta*l$s sta*l$sh h sta*le &onta&t $n th$s pos$t$on
37
!nformation gat$ering8 $istory9 e5amination9 diagnosis and treatment planning
he gathering of information and a .onsideration of its :istory and complaint possible signif signifi.an.e i.an.e for the .are of a pati ent Ideally) the initial information should be gathered in a neutral shouldas soon begin soo n as the dentist and patient first meet9 =or environment) aay from the dental .hair) here both here both patient and e*ample e*a mple ) if the patient the patient appears to b bee biologi.ally old then one dentist .an be more aare of body of body language as ell as verbal might anti.ipate an ti.ipate that there .ould be be problems problems ith adaptat ion .ommuni.at ion9 I t is .ru.ial that the the patie patient
T
Figure @ 1 /
istor and coplaint
I% a '$s&repan&. *et-een the pat$ent 2s epe&tat$ons an' the res#lt o% trea t)ent 'oes o&r $t &an have a pro%o#n' e%%e&t on *oth pat$ent treat)ent an' 'ent $st , an' )a. also a%%e&t %#t#re treat)ent ep$so'es
I< .
P
Poor treatment result
Poor dentist motivation
Poor patient motivation
"enture history The patient
o
3#
A clinical guide to removable partial dentures original diagnosis might have been in.orre.t9 =or e*ample) if e*pe.tations of hat a removable prosthesis .an a.hieve9 I t relining failed to resolve a .omplaint oflooseness) then the .ause is essential that the dentist modifies these e*pe.tations as possibly not a poor fit9 ;oever) the original appropri ately at an early stage by .areful e*planation and diagnosis should no t be dis.arded until e*amination of the dis.ussion oth erise the prognosis for any future !"s ill dent ure has shon that the previous ad6ustments ere .arried remain poor9 - model of a denture similar to the one that is out adequately9 planned .an be a useful aid in helping the pati ent to I % a patient .omplains about an !") even though it appears understand the situation more .learly9 to be satisfa.tory) it may be be.ause the patient has unrealisti.
Figure '92a and !.2b -
'enture histor
Move)ent o% the RP! '#r$n3 %#n&t$on , part$larl. -hen $n&$s$n3 +a &an *e a tro#*leso)e l$)$tat$on o% lar3e prostheses The ne&ess$t. %or ton3#e &ontrol )#st *e epla$ne' to the pat$ent Te&hn$F#es &an *e 'e)onstrate' , %or ea)ple, *. ask$n3 the pat$ent to 2h#)p #p the *a&k o% the ton3#e2 to s#pport the poster$or *or'er o% a )a$llar. 'ent#re '#r$n3 $n&$s$on * A s)all *ea' o% -a or $)press$on &o)po#n' pla&e' at the poster$or e'3e o% the 'ent#re &an a&t as a 2tar3et2 to help the pat$ent lo&ate the &orre&t spot The pat$ent $s $n%or)e' that s#&h 'el$*erate &ontrol -$ll $n$t$all. *e a &ons&$o#s a&t$v$t. *#t event#all. *e&o)es a#to)at$& The t$)e taken %or s#&h ha*$t#at$on to o&r -$ll var. I% the pro&ess $s epe&te' to *e prolon3e' *e&a#se o% a'van&e' a3e or &hron$& $llness, the pat$ent sho#l' *e -arne' a&&or'$n3l. an' en&o#ra3e' to persevere Th$s preparat$on o% the pat$ent $s part$larl. $)portant %or the nov$&e 'ent#re/-earer , or %or pat$ents -ho have a h$stor. o% 'ent#re pro*le)s o% th$s t.pe
"ental history The previous dental history .an signifi.antly influen.e the therefore soon lose their fit9 patient
40
!nformation gat$ering8 $istory9 e5amination9 diagnosis and treatment planning I1
Figure !.3 -
5/
Sp$nal pro*le)s asso&$ate', %or ea)ple , -$th osteoporos$s or ank.los$n3 spon'.l$t$s, -$ll ne&ess$tate &are%#l pos$t$on$n3 o% the 'ental &ha$r to avo$' '$s&o)%ort / so) et$)es to the po$nt -here the operator has to a&&ept a pos$t$on that $s less than $'eal %or &arr.$n3 o#t treat)ent Th$s $s part$larl. so $% a &erv$&al &ollar $s -orn Pat$ents Nho are over-e$3ht, $n an a'van&e' sta3e o% pre3nan&. or -ho have sev ere anae)$a or &ar'$a& %a$l#re are also $ntolerant o% the s#p$ne operat$n3 pos$t$on
5/
-
a
Medical histor
!atients at ris5 of infe.tive endo.arditis require .areful treat ment planning in.luding provision of prophyla.ti. antibioti. .over for any pro.edure li5ely to .reate a ba.teraemia) and then effi.ient s.heduling of appointments to ma5e best use of the peri$
F igure !.4 /
ods of .over as ell as thorough oral and denture hygiene rein for.ement9 Invasive pro.edures for patients ith adrenal insuf fi.ien.y may require prophyla.ti. steroid .over9
Medical histor
an. %a&tors re'#&e the a*$l$t. o% the oral )#&osa to res$st )$&ro*$al, )e&han$&al, &he)$&al or ther)al atta&k or ea)ple, s)ok$n3 ))#no/s#ppress$on )#&osal '$sor'ers s#&h as pe)ph$3#s +as sho-n here an' l$&hen plan#s h.posal$vat$on -hether pro'#&e' as a s$'e/e%%e&t o% a n#)*er o% 'r#3s or *. 3lan'#lar '$sease s #&h as S$$3ren2s s.n'ro)e Eros$on an' so%ten$n3 o% har' tooth t$ss#e &an res#lt %ro) %reF#ent vo)$t$n3 pro'#&e' *. 3astro/$ntest$nal '$sease , re3#lar '$etar. $n'$s&ret$ons or ps.&holo3$&al '$sor'ers s#&h as anore$a nervosa or *#l$)$a The rate o% resorpt$on o% alveolar *one &an *e $n&rease' $n osteoporos$s -h$&h $s &o))on $n %e)ales a%ter the )enopa#se -ho are not re&e$v$n3 hor)one repla&e)ent therap. , an' 5n )ales over 90
F igure ' 9 # $ Medical histor The pra&t$&e o% oral an' 'ent#re h.3$ene )a. *e &o)pro)$se' *. a re'#&e' a*$l$t. to Hol' an' )an$p#late oral h.3$ene a$'s s#&h as tooth*r#shes an' %loss +arthr$t$s, as $n th$s &ase, or ne#ro)#slar '$sease See 'e*r$s an' plaF#e +v$s#al $)pa$r)ent Hear $nstr#&t$ons +hear$n3 $)pa$r)ent Co)prehen' the ne&ess$t. %or the pro&e'#res
I1
e#ro)#slar &ontrol o% 'ent#res -$ll *e a'versel. a%%e&te' *. &ere*ro/vaslar a&&$'ents , %a&$al paral.s$s an' other ne#ro)#slar pro*le)s s#&h as Park$nson 2s '$sease
Social and personal history - smo5ing habit sho uld be noted as this has a detri mental It may be.ome apparent that the patient is being .oer.ed by rel effe.t on the periodontal tissues) as ell as on general health9 atives into having dentures rather than being motivated to obtain The patient
1
A clinical guide to removable partial dentures +5amination Figure @6a and @ 6b /
=*tra-oral
Ea)$nat$on sho#l' *e3$n -$th an etra / oral assess)ent o% %a&$al %or) an' s.))etr. , a st#'. o% a- open$n3 an' &los$n3 )ove)ents, to3ether -$th palpat$on o% the te)poro)an'$*#lar o$nts an' )#s&les o% )ast$&at$on The $n%or)at$on 'er$ve' %ro) these o*servat$ons $s help%#l $n the assess)ent o% the health o% the )ast$&ator. s.ste) The 'ev$at$on o% th$s pat$ent2s )an'$*le to the le%t on &los$n3 $n'$&ates poss$*le '$shar)on. that sho#l' *e $nvest$3ate'
Figure '9 ! /
Intra-oral
Prel$)$nar. v$s#al $nspe&t$on o% the )o#th -$ll $n'$&ate the *as$& stan'ar' o% oral h.3$ene, the level o% &ar$es s#s&ept$*$l$t. an' the F#al$t. o% the e$st$n3 restorat$ons Spe&$al attent$on sho#l' * e '$re&te' to an. areas o% spe&$%$& &o)pla$nt an' $t )a. *e ne&essar. to $nst$t#te e)er3en&. treat)ent %or the rel$e% o% pa$n In th$s $nstan&e there $s a nee' to $)prove the stan'ar' o% oral h.3$ene an' to repla&e a n#)*er o% the e$st$n3 restorat$ons
Figure " .# -
Intra-oral
Deta$le' ea)$nat$on sho#l' &o))en&e -$th the so%t t$ss#es The )#&osa o% the l$ps , &heeks, ton3#e , palate an' %loor o% the )o#th sho#l' *e ea)$ne' an' ton3#e )ove)ents o*serve' $n or'er to e&l#'e patholo3. Here , the )#&osa appears to *e nor)al
Figure ".9 -
Intra-oral
The $n'$v$'#al 'ental ar&hes sho#l' *e &are%#ll. $nspe&te' , the lo&at$on o% e'ent#lo#s spa&es note' an' the '$str$*#t$on an' al$3n)ent o% the re)a$n$n3 teeth &are%#ll. assesse' $n relat$on to these spa&es Here there has *een v$rt#all. no )ove)ent o% the teeth a'a&ent to the anter$or e'ent#lo#s area a'eF#ate spa&e $s ava$la*le %or the three repla&e)ent teeth The sa)e &annot *e sa$' o% the )olar spa&e , -h$&h has *een )arke'l. re'#&e' *. rotat$on o% 5@
$
!nformation gat$ering8 $istory9 e5amination9 diagnosis and treatment planning i gure @ 1$ / ral /or al
)9 a
Intra-oral
n e presen&e o% 3$n3$val or )#&osal $n%la))at$on $n an area &overe' o. a prev$o#s 'ent#re sho#l' *e note' so that appropr$ate treat)ent )a. *e $n$t$ate'
e o% F
=! r.
Figure !.11 /
Intra-oral
The %or) o% the res$'#al r$'3es an' the &o)press$*$l$t. o% the $nvest$n3 so%t t$ss#es $n the e'ent#lo#s areas sho#l' *e assesse' v$s#all. an' *. palpat$on In&l#'e' $n th$s ea)$nat$on $s the har' palate s$n&e n&o)press$*le areas )a. have to *e avo$'e' *. 'ent#re )ar3$ns
led #te
a 2 *er
Figure @ 12 /
Intra-oral
The $nte3r$t. o% e$st$n3 restorat$ons sho#l' *e &are%#ll. &he&ke' an' &ar$o#s &av$t$es &harte'
Figure '9 13 /
Intra-oral
The health o% the per$o'ontal t$ss#es sho#l' *e 'eter)$ne'
$at$on
Fe
h$&h
The standard of plaque .ontrol should be assessed and dis.los ing agents may be used to demonstrate the presen.e of plaque to the patientB plaque s.ores may be re.orded9 !o.5et depth should
he measured and .harted 9 -ny mobility of the remaining teeth should be noted) espe.ially if they are potential abutment teeth9 The :ritish !eriodontal @*amination 7:!@8) or ommunity
3
A clinical guide to removable partial dentures !eriodontal Inde* of Treatment Need 7!ITN8) .an be used to routinely s.reen patients requiring !"s9 The dental ar.hes should then be e*amined in o..lusion and a very .riti.al assessment made of the stability of the o..lusion 9 losure into the inter.uspal position should be an automati.
refle* pro.edure9 Ideally) simultaneous bilateral .onta.t should ta5e pla.e9 -ny .onta.t that disturbs this pattern should be noted) parti.ularly if it gives rise to displa.ement of the mandible into a position of a..ommodation9
Figure '9 14 /
Intra-oral
In th$s )o#th the $n$t$al &onta&t on &los#re takes pla&e *et-een the &an$ne teeth on the r$3ht s$'e
Figure '9 1% /
Intra-oral
The )an'$*le has no- *een 3#$'e' %or-ar' $nto a post#ral pos$t$on $n -h$&h there $s s#*stant$al &onta&t *et-een the oppos$n3 'ent$t$ons $n the anter$or an' poster$or re3$ons
:efore a treatment plan is established) it must be de.ided hether the e*isting o..lusal relationship should be a..epted oitr should be modified either by equilibration to hether elimi$
$
Ul$l$ll=$*Q$ $$ Q
11
!
/
nate the initial .anine .onta.t or by re.onstru.ting the defi.ient posterior o..lusion at the o..lusal verti.al dimension established by the initial .onta.t9
Figure '9 16 /
Intra-oral
!&&l#sal $n'$&ator -a , art$lat$n3 paper or tape , an' th$n )etal %o$l +sh$)sto&k )a. *e help%#l $n a &l$n$&al assess)ent o% the o&&l#s$on It $s also help%#l to )o#nt st#'. &asts on an art$lator
!nformation gat$ering8 $istory9 e5amination9 diagnosis and treatment planning I' ', to
Figure @ 1! /
Intra-oral
An. 'r$%t$n3 or t$lt$n3 o% teeth that )a. hav e *een note' -hen the $n'$v$'#al 'ental ar&hes -ere ea)$ne' sho#l' *e reassesse' $n relat$on to the oppos$n3 ar&h The a*nor)al pos$t$on )a. &ontr$*#te to o&&l#sal %a#lts or to pro*le)s -hen 'es$3n$n3 a 'ent#re $n the other a- !ver/er# pte' te eth, s#&h as 5;, 5: an ' ;@, sho#l' also *e note' as re)e'$al treat)ent $n the %or) o% o&&l#sal eF#$l$*rat$on , re'#&t$on $n he$3ht an' restorat$on *. )eans o% &ro-ns , or even etra&t$on )a. *e reF#$re'
Figure '9 1" /
Intra-oral
E$st$n3 RPDs sho#l' *e ea)$ne' The 'es$3n an' F#al$t. o% &onstr#&t$on sho#l' *e note' an' an. asso&$ate' pro*le)s $n relat$on to 3$n3$val an' )#&osal $n%la))at$on or to 'e&al&$%$&at$on o% &onta&t$n3 tooth s#r%a&es &are%#ll. eval#ate' It $s $)portant to assess -hether or not the 'ent#re st$ll %$ts a&ratel. The appearan&e o% the 'ent#re sho#l' also *e note'
Figure '9 1( /
Intra-oral
The 'e3ree to -h$&h the 'ent#re restores o&&l#sal &onta&t sho#l' *e assesse' Here, alveolar resorpt$on an' o&&l#sal -ear o% the art$%$&$al teeth have res#lte' $n la&k o% poster$or tooth &onta&t , &a#s$n3 $n&rease' loa'$n3 on the anter$or teeth
ent hed
It
Figure ".$% -
Intra-oral
Ra'$o3raphs sho#l' *e o*ta$ne' to &he&k %or ne- or rerrent &ar$o#s les$ons that )a. not have *een reveale' *. &l$n$&al $nspe&t$on, to reveal the etent o% an. *one loss that )a. *e present an' also to $'ent$%. an. patholo3$&al &han3es -$th$n the a-s The F#al$t. o% the e$st$n3 restorat$ons an' the 'e3ree o% *one loss $n the $nterpro$)al areas &an *e assesse' %ro) th$s *$te-$n3 ra'$o3raph
%
A clinical guide to removable partial dentures iagnosis preventivee adv preventiv advi.e i.e be.omes be.omes apparent9 ;o ;oev ever) er) it is impor tant to dra up a provis provisional ional t r atment plan at the outset hile hile all all the .olle.ted .olle. ted informa information tion is fresh in the dentist
I % the reason for the patient
46
Preliminary • ? 1mpress1 ons
! e
reliminary impressions of a patient
designing of !"s) and for the .onstru.tion of individual trays hi.h ill be ill be used to obtain the more a..urate or5ing impres sions required for the .onstru.tion of the !"s9
the Figure ".1 Sto&k tra.s are ava$la*le $n a var$et. o% s$es an' shapes The. )a. *e per%orate' or #nper%orate', )etal or plast$&, o% s$)ple *o 'es$3n or shape' to %$t *$lateral '$stal etens$on sa''les
Figure ".2 A s$e o% tra. $s sele&te' so that the teeth s$t &entrall. -$th$n the tro#3h o% the tra. I% poss$*le there sho#l' *e a spa&e o% a*o#t ;)) *et-een the %lan3e o% the tra. an' the *#&&al an' la*$al s#r%a&es o% the teeth
47
A clinical guide to removable partial dentures
? ? ?? ????
Be&a#se the ran3e o% sto&k tra.s $s l$)$te' $t -$ll &o))onl. *e %o#n' t hat an $'eal s$e an' shape o% sto&k tra. $s not ava$la*le In th$s ea)ple, the ) a$llar. sto&k tra. 'oes not &over the la*$al s#r%a&es o% the teeth s#%%$&$entl., ne$ther 'oes $t $n&l#'e the )ost poster$or teeth
Figures ".% and ".6 There )a. also * e re3$ons -here the tra. $s poorl. a'apte' to the #n'erl.$n3 str#&t#res s#&h as the palate or a sa''le area
Figures ". ' and "." In ea&h &ase the 'ea' spa&e sho#l' *e %$lle' *. pla&$n3 a h$3h/v$s&os$t. )ater$al, s#&h as $)press$on &o)po#n' , $n the appropr$ate area S$l$&one p#tt. $s a s#$ta*le alternat$ve alternat$ve )ater$al %or th$s tra. &orre&t$on +$3#re 859 The )ater$al $s then )o#l'e' $n the )o#th
48
7B
F FF F F ? ?? ? o? ? ? ? •• • F F F ? F ?? ••? ?
Figures " .3 and ".4
e
?
Preliminary impressions
Figures ".( and ". 1$ L$n3#al *or'er )o#l'$n3 o% the &o)po#n' $s a&h$eve' *. the pat$ent %$rst p#sh$n3 the ton3#e to &onta&t the #pper l$p / a n ' then thr#st$n3 the ton3#e $nto ea&h &orner o% the )o#th $n t#rn
Figures ".11 and ".12 An. are as o% the $)press$o n &o)po#n' -h$&h ar e over/eten'e' sho#l' *e &orre&te' *. tr$))$n3 a-a. the e&ess )ater$al, reso%ten$n3 $n a %la)e an' te)per$n3 $n -ar) -ater *e%ore repeat$n3 the *or'er )o#l'$n3
Figure " . 13 Co)po#n' that has &onta&te' the teeth sho#l' *e t a-a. as $t )a. prevent a&rate re/$nsert$on o% the $)press$on tra. an' -$ll el$)$nate spa&e aro#n' the teeth ne&essar. %or a s#%%$&$ent th$&kness o% the al3$nate #se' to &o)plete the prel$)$nar. $)press$on
Figure ".14 Un'er / etens$on $n the la*$al re3$on &an *e &orre&te' *. the a''$t$on o% $)press$on &o)po#n' to the 'e%$&$ent areas o% the tra. to %or) a sl$3htl. over/eten'e' %lan3e
49
A clinical guide to removable partial dentures Figure ".1% The tra. $s then seate' $n the )o#th -h$le the &o)po#n' $s st$ll so%t an' *or'er )o#l'$n3 $s &arr$e' K o#t B#&&al an' la*$al )o#l'$n3 o% *oth )a$llar. an' )an'$*#lar $)press$ons $s a&h$eve' *. s#pport$n3 the tra. -$th one han' -h$le )an$p#lat$n3 the &heeks an' l$ps -$th the other
Figure ".16 (hen a -ater *ath $s not ava$la*le %or so%ten$n3 the $)press$on &o)po#n' , alternat$ve )ater$als, s#&h as s$l$&one p#tt. or p$nk )o'ell$n3 -a , )a. *e #se' to )o'$%. the tra.
n.e modifi.ation of the sto.5 tray has been .ompleted any additions of .ompound or a* are thoroughly .hilled and the tray is dried9 - thin layer of adhesive is applied and alloed to
dry before the tray is loaded ith alginate9 The tray is then seated in the mouth and the impression material border$ moulded9
Figures ". 1! and ". 1" The &o)plete' $)press$on $s assesse' *. &ons$'er$n3 three aspe&ts 5 Those s#ls areas -h$&h -$ll *e relate' to the 'ent#re *or'ers < The e'ent#lo#s areas > Th e te et h The $)press$on on the le%t $s sat$s%a&tor., the one on the r$3ht sho-s a n#)*er o% %a#lts the tra. has *ee n pos$t$one' too %ar to the pat$ent2s r$3ht the *or'ers o% the al3$nate are #ns#pporte' the $)press$on $s #n'er eten'e' $n the post/'a) re3$on
I % on inspe.tion the impression is found to be satisfa.tory) it fe.ted9 The impression should be sha5en to remove any e*.ess is rinsed th oroughly to remove all tra.es of saliva and is disin $ moisture9
so
Preliminary impressions Figure ".1( r$'
An $n'el$*le pen&$l l$ne )a. *e 'ra-n on the $)press$on to $n'$&ate to the 'ental te&hn$&$an the reF#$re' etens$on o% the $n'$v$'#al tra. The &o)plete' $)press$on )#st *e prevente' %ro) 'r.$n3 o#t *. &over$n3 $t -$th a 'a)p napk$n an' pla&$n3 $t $n a plast$& *a3
Figure ".2$ ( h$le the $)press$on $s -a$t$n3 to *e &ast the tra. sho#l' *e s#pporte' so that $ts o-n -e$3ht $s not appl$e' to the *or'ers o% the $)press$on I% th$s $s not 'one , per)anent 'e%or)at$on o% the $)press$on -$ll o&r The $)press$on )#st *e &ast as soon as poss$*le to avo$' $na&ra&$es 'evelop$n3 as a res#lt o% the '$)ens$onal $nsta*$l$t. o% al3$nate
'
!nstructions to t$e laboratory In order to obtain the best results from !" treatment ) it is essen tial that the dentist and the dental te.hni.ian or5 effi.iently together as a team9 @a.h should understand the role and require ments of the other so that they .an .ollaborate effe.tively9 An essen tial part of this pro.ess is effi.ient .ommuni.ation9 There must be an e*.hange of a..urate and .omprehensive information9 hen sending or5 to the dental te.hni.ian) the dentist must produ.e a ritten) detailed or5 authorisation supplemented) here ne.essary) by verbal .ommuni.ation9 The .ontents of this authorisation ill vary to a .ertain e*tent a..ording to the .lin i.al stage and lo.al requirements9 ;oever) guidelines have been produ.ed and these are des.ribed in more detail in A Clinical Guide to Removable Partial Denture Design& .hapter /9
The authorisation sent ith the preliminary impression s should in.lude the folloing9 /9 "etails of the patient and the dental pra.ti.e9 29 onfirmation that the .lini.al items have been disinfe.ted9 39 "ate of the ne*t appointment9 49 - request for the study .asts to be surveyed if required 9 #9 - request for a* o..lusal rims here ne.essary) if mounting of the study .asts on an arti.ulator 7.hapters , and /'8 is required to assist in the !" design stage9 %9 1pe.ifi.ation of the material and design of the individual impression trays9 '9 1i>e and lo.ation of any stops to be preformed in the tray9
&l
Articulators
n arti.ulator is a hinge$li5e devi.e) hi.h .an be used to position the ma*illary and mandibular .asts in a .hosen elationship to ea.h other9 There are many different
designs of arti.ulator) several of hi.h reprodu.e some of the movements of hi.h the mandible is .apable9
#ypes of articulator Figure (. 1 / inge articulator Th$s s$)ple art$lator hol's the &asts $n a pres&r$*e' relat$onsh$p , #s#all. the $nterspal pos$t$on, an' allo-s separat$on an' appro$)at$on o% the &asts The h$n3e $s $n no -a. relate' to the h$n3e a$s o% the )an'$*le an' there $s no atte)pt to repro'#&e )an'$*#lar )ove)ent Th#s -$th th$s t.pe o% art$lator $t $s poss$*le to pro'#&e even o&&l#sal &onta&t onl. $n the re&or'e' stat$& a- relat$onsh$p The l$)$tat$ons o% th$s 'ev$&e have lon3 *een re&o3n$se' I% th$s $nstr#)ent $s #se' at all $t )#st *e $n &$r)stan&es -here the o&&l#s$on $s to *e restore' to an e$st$n3 sta*le $nterspal relat$onsh$p an' -here the ers$ve 3#$'an&e s o% the re)a$n$n3 nat#ral teeth -$ll ens#re separat$on o% those teeth repla&e' *. the RP! It -$ll also *e ne&essar. to $'ent$%. an' el$)$nate o&&l#sal '$s&repan&$es -hen the restorat$on $s $nserte' $n the )o#th
Figure (.2 -
Average oveent articulator
Art$lat ors o% th$s t. pe have the$r or$3$ns $n the -ork o% Mo nson , Bon-$ll an' G.s$, -ho re&or'e' )eas#re)ents %ro) anato)$&al spe&$)ens an' &l$n$&al s#*e&ts $n or'er to 'evelop art$lators -hose '$)ens$ons re%le&te' those anato)$&al %eat#res -h$&h $n%l#en&e )an'$*#lar )ove)ent The '$)ens$ons o% these art$lators re%le&t the avera3e )eas#re)ent re&or'e' *. Bon-$ll o% 5De) *et-een the &entral po$nts o% the )an'$*#lar &on'.les an' *et-een these po$nts an' the )$'po$nt o% the $n&$sal e'3es o% the )an'$*#lar anter$or teeth These '$)ens$ons %or) an eF#$lateral tr$an3le , kno-n as Bon-$ll2s tr$an3le
53
A clinical guide to removable partial dentures Figure (.3 -
Average oveent articulator
These art$lators also $n&orporate a &on'.lar path represent$n3 the avera3e sa3$ttal &on'.lar 3$'an&e an3le o% appro$)atel. >0 The )a$llar. &ast $s )o#nte' $n $ts &orre&t pos$t$on relat$ve to the &on'.lar a$s *. )eans o% a lo&at$n3 'ev$&e s#&h as an $n&$sal p$n, or $n so)e $nstan&es *. the #se o% a %a&e*o- +$3#re 79 Th$s 3ro#p o% ar*$trar. )ove)ent art$lators $s -$'el. #se' $n 'ental pra&t$&e *#t &learl. has l$)$tat$ons $n the$r &apa&$t. to repl$&ate )an'$*#lar )ove)ent
Semi-ad#ustable articulators In order to reprodu.e the mandibular movements of individual patients ith any degree of a..ura.y) arti.ulators need to be ad6ustable to .onform to those anatomi.al features) su.h as in.isal guidan.e and .ondylar guidan.e) hi.h influen.e those move ments9 They should also ta5e a..ount of the bodily shift of
the mandible 7:ennett movement 8 during lateral e*.ursion9 To basi. types of ad6ustable arti.ulators are available) both of hi.h produ.e a reasonable simulation of anatomi.al relation ships and movements9 This allos a satisfa.tory o..lusal fun. tion to be restored in a ide variety of .lini.al situations9
Figure (.4 -
Arcon articulators 9andibulA ,+5dle:
Art$lat ors o% the ar&on t.pe, s#&h as the (h$p)$ an' Denar ser$es , have a &on'.lar ele)ent on the lo-er )e)*er -h$&h $s a*le to sl$'e a3a$nst an a'#sta*le plane on the )a$llar. &o)ponent o% the art$lator A Denar $nstr#)ent $s $ll#strate' here
Figure (. : /
5on-arcon articulators
In th$s 3ro#p o% art$lators, l$ke the Dentat#s T.pe ARL $ll#strate' here, the &on'.lar sphere $s part o% the #pper )e)*er o% the art$lator an' $s &onta$ne' -$th$n an a'#sta*le tra&k $n the &on'.lar p$llar o% the lo-er ele)ent
%
Articulators
!ecords required for semi-ad#ustable articulators Figure (.6a and (.6b / Facebo/ trans#er A prereF#$s$te o% all a'#sta*le art$lators $s that the &ast o% the )a$llar. 'ent$t$on sho#l' *e lo&ate' a&ratel. $n relat$on to the )an'$*#lar &on'.les an' to a hor$ontal plane o% re%eren&e, #s#all. the rank%ort plane A %a&e*o- $s #se' to re&or' th$s $n%or)at$on &l$n$&all. +a an' to trans%er $t to the art$lator +*
$cclusal records I% the inter.uspal relationship is .omfortable and ell$defined it should be a..epted) parti.ularly if e*.ursive guidan.es are estab lished by the natural dentition9 I% all the remaining posterior teeth o..lude very pre.isely it may be possible to lo.ate the .asts in the
Figure (. ' $
inter.uspal position 9 The .asts must then be se.urely lo.ated together before being mounted on the arti.ulator 9 -lternatively) the relationship may be re.orded using a a* template shaped as in =igure ,9'9
+cclusa7 records
I% there $s a 'ev$at$on on &los$n3 %ro) the %$rst &onta&t pos$t$on to $nterspal pos$t$on , $t $s essent$al to anal.se the o&&l#s$on an' lo&ate the $nter%eren&e In these &$r)stan&es $t $s a'v$sa*le to o*ta$n a re&or' o% the retr#'e' a- relat$onsh$p #st pr $or to tooth &onta&t The re&or'$n3 te)plate $s )a'e %ro) t-o th$&knesses o% to#3hene' -a It $s #s#all. a'v$sa*le to tr$) the te)plate to avo$' $n&$sal &onta&t A horseshoe shape $s not s#%%$&$entl. r$3$' The -a $s so%tene' , pla&e' $n the )o#th an' the )an'$*le 3#$'e' $nto &los#re alon3 the retr#'e' h$n3e a$s Tooth /to/tooth &onta&t thro#3h th$s -a )#st *e avo$'e' as th$s )a. &a#se 'ev$at$on o% the )an'$*le
Figure (." /
+cclusal records
I% there are $ns#%%$&$ent teeth re)a$n$n3 %or a re&or' o% th$s t.pe to *e #se' s#&&ess%#ll. , $t -$ll *e ne&essar . to &onstr#&t -a o&&l#sal r$)s These are a'#ste' $n the )o#th to re&or' the pres&r$*e' arelat$onsh$p, as 'es&r$*e' $n Chapter 5@
%%
A clinical guide to removable partial dentures Figure ,9 , $
+cclusal records
(hen an a'#sta*le art$lator $s to *e #se' , $t $s ne&essar. to prepare -a $n'$&es to re&or' the a- relat$onsh$p $n protr#s$ve , or $n r$3ht an' le%t lateral ers$ons These $n'$&es are #se' to set the &on'.lar 3#$'an&e an3les on the art$lator Here $s an ea)ple o% a re&or' o% a r$3ht lateral ers$on In th$s par t$lar $nstan&e the a&ra&. o% the tooth $n'entat$ons has *een $n&rea se' *. #s$n3 re3$strat$on paste on the -a -a%er All %a&e*o- re&or 's an' -a $n'$&e s )#st *e '$s$n%e&te ' an' serel. pa&ke' *e%ore sen'$n3 to the la*orator.
Figure 7 1$ /
Full ad0ustable articulators
These are soph$st$&ate' art$lators -$th a )ore &o)prehens$ve s.ste) o% a'#st)ent , -h$&h 3$ves the) the potent$al %or $n&rease' a&ra&. $n the repro'#&t$on o% )an'$*#lar )ove)ent "ar$o#s )etho's have *een 'ev$se' %or pro3ra))$n3 these $nstr#)ents or ea)ple , *. o*ta$n$n3 tra&$n3s o% )an'$*#lar )ove)ent $n three planes #s$n3 an $nstr#)ent &alle' a panto3raph an' then trans%err$n3 these re&or's to the art$lator The$r #se 'e)an's a h$3h 'e3ree o% sk$ll on the part o% the 'ent$st an' 'ental te&hn$&$an an' the &l$n$&al pro&e'#res are t$)e/&ons#)$n3 The. are )ore l$kel. to *e #se' $n treat)ent $nvolv$n3 Ps rather than RPDs
%!
Part P - reparation of t$e mout$ T
he .hapters in !art 2 des.ribe pro.edures for .reating the best possible oral envi ronment for the provision of an !" and are arranged in the sequen.e most .om monly appropriate to .lini.al pra.ti.e9 ;oever) it should be remembered that there ill be o..asions hen several of the pro.edures are underta5en .on.urrently) or hen it is ne.essary to alter the sequen.e9 -n e*ample of a typi.al .ourse of treatment might be as follos9 Impressions for study .asts are obtained and a provisional design produ.ed at the out set be.ause the design of the proposed applian.e may ell influen.e) or be influen.ed by) subsequent treatment su.h as e*tra.tions) orthodonti.s and the design of tooth restora tions9 -ny treatment required to stabilise the patient
#'
10 I
!nitial prost$etic treatment
nitial prostheti. trea tment may involve modifi.ation of an e*isting denture or provision of an interim prosthesis as a preparation for the definitive .ourse of treatment9 hen modifying e*isting dentures the folloing points should be bo rne in mind9 =irstly) as these dentures are .ommonly due for early repla.ement) modifi.ations ill not have to last for very long9 1e.ondly) the patient ill often be relu.tant to part ith the denture for the modifi.ations to be .arried out) parti.ularly if it repla.es anterior teeth9 These .onsiderations point to modifi.a tion of the denture at the .hairside herever pra.ti.able9 - range
Figure 1$.1 /
of polymers for dire.t use in the mouth signifi.antly in.reases the number of opportunities for adopting this approa.h 9 Their relatively short .lini.al life) usually measured in months rather than years) is not a problem here early repla.ement of the den ture is anti.ipated9
'epairs and additions :efore underta5ing a repair it is essential to determine the .ause of the fra.ture so that appropriate .orre.tive measures .an be underta5en9
,lasps and rests
To repla&e %ra&t#re' &lasps an' rests , or to a'' these &o)ponents to a 'ent#re, an al3$nate $)press$on $n a sto&k tra. $s reF#$re' o% the 'ent#re in situ. Great &are )#st *e taken to ens#re that the $)press$on )ater$al 'oes not '$spla&e the 'ent#re %ro) $ts &orre&t relat$onsh$p to the s#rro#n'$n3 t$ss#es (here a &o)ponent $s to * e a''e' an' the o&&l#s$on -$ll $n%l#en&e the 'es$3n or pos$t$on o% that &o)ponent , an $)press$on o% the oppos$n3 'ent$t$on $s also nee'e' I% $t -$ll not *e poss$*le to pla&e the &asts *. han' $nto the $nterspal pos$t$on an $ntero&&l#sal re&or' -$ll *e reF#$re' to allo- the &asts to *e )o#nte' on an art$lator
Figure 1$ .2 /
,lasps and rests
A ne- &lasp ar ) $s #s#all . pr o'#&e' *. a'apt$n3 a -ro#3ht sta$nless steel -$re to the tooth on the &ast an' then atta&h$n3 the -$re to the e$st$n3 a&r.l$& *ase +5 Alternat$vel., an ent$rel. ne- &lasp asse)*l. &an *e &ast an' ta33e' $nto the sa''le o% the 'ent#re +< Th$s latter pro&e'#re -o#l' nor)all. *e #n'ertaken onl. $% the e$st$n3 'ent#re $s to *e #se' %or a &ons$'era*le t$)e
#,
A clinical guide to removable partial dentures Figure 1$ .3 -
)eeth
I% a tooth has *e&o)e 'eta&he' %ro) the 'ent#re *#t $s st$ll ava$la*le, a rap$' &ha$rs$'e repa$r &an #s#all. *e e%%e&te' #s$n3 &ol'/r$n3 a&r.l$& res$n It $s a'v$sa*le to t so)e %or) o% )e&han$&al retent$on $n or'er to re$n%or&e the &he)$&al *on'
The addition of a ne artifi.ial tooth may be required to fill a spa.e .reated either by loss of a denture tooth or by e*tra.tion of a natural tooth9 This is often best done by obtaining an alginate impression and intero..lusal re.ords) as des.ribed in =igurel9l) so that the addition .an be made in the laboratory9
Figure 1$.4a and b /
-lternatively) it may be possible to rapi dly a.hieve an a..ept able result by building up a repla.ement tooth by dire.t additions of tooth$.oloured .old$.uring a.ryli. resin to the denture at the .hairside9
)eeth
The atta&h)ent o% teeth to )etal &onne&tors &an *e a&h$eve' *. the &reat$on o% )e&han$&al retent$on s#&h as per%orat$ons or sol'ere' -$re loops Alternat$vel., a&r.l$& &an *e *on'e' to &o*alt/&hro)$#) #s$n3 )eta a'hes$ves
Figure 1$ .# $
,onnectors
I% the port$ons o% a %ra&t#re' a&r.l$& 'ent#re &an *e relo&ate' a&ratel. o#ts$'e the )o#th , the &l$n$&$an &an #n$te the) -$th a -$re ro' hel' on to the o&&l#sal s#r%a&es -$th st$&k. -a , or *. appl.$n3 a &.ano a&r.late a'hes$ve to the %ra&t#re s#r%a&es I% poss$*le the asse)*le' 'ent#re sho#l' then *e tr$e' $n the )o#th %or a&ra&. *e%ore *e$n3 sent to the la*orator. %or repa$r Alternat$v el. , a &ha$rs$'e repa$r #s$n3 &ol'/r$n3 a&r.l$& res$n $s so)et$)es poss$*le
!0
!nitial prost$etic treatment Figure 1$.6 /
,onnectors
I% the port$ons o% the 'ent#re 'o not relo&ate a&ratel. o#ts$'e the IT!#th the. sho#l' *e hel ' $n the *est poss$*le relat$onsh$p *. an appl$&at$on a&ross the %ra&t#re l$ne o% &ol'/r$n3 a&r.l$& res$n or $)press$on &o)po#n' The 'ent#re )a. then *e seate' $n the )o#th -h$le the *on'$n3 )ater$al $s st$ll pl$a*le, an' *oth port$ons hel' $n the$r &orre&t relat$on to the r$'3es an' teeth #nt$l the 'ent#re $s r$3$'l. #n$te' A la *orat or. r epa$r &an t hen *e #n 'ertak en I% appos$t$on &annot *e a&h$eve', or $% a )etal &onne&tor $s *roken or *ent, the 'ent#re -$ll #s#all. have to *e re)a'e
Figure 1$.' $ e
Flanges
The a''$t$on or etens$on o% a %lan3e )a. *e a&h$eve' #s$n3 a non/ pol. )eth.l )etha&r.late res$n, s#&h as *#t.l )etha&r.late res$n, -h$&h $s a'apta*le '$re&tl. $n the )o#th Ho-ever , as the &olo#r sta*$l$t. o% these res$ns $s relat$vel. poor, the te&hn$F#e $s not $'eal $% the %lan3e $s v$s$*le an' the 'ent#re $s to *e -orn %or )ore than a %e- -eeks or the la*orator. a''$t$on o% a %lan3e, an al3$nate $)press$on $n a sto&k tra. $s o*ta$ne' o% the 'ent#re in situ. The tra. -$ll #s#all. nee' to *e eten'e' $n the area -here the %lan3e $s to *e a''e' #s$n3 a s#$ta*le *or'er / )o#l'$n3 )ater$al
Figure 1$.' $ Flanges Alternat$ vel. a *o r'er/) o#l'$n 3 )ater $al, $n th$s &ase t ra&$n3 &o)po#n', &an *e a''e' to the 'ent#re an' shape' to &on%or) to the area to *e &overe' *. the %lan3e A lo&al -ash $)press$on $s then taken -$th$n the )o'$%$e' %lan3e An over /$)press$on o% the teeth an' 'ent#re in situ #s$n3 al3$nate $n a sto&k tra. -$ll %a&$l$tate the la*orator. -ork
l.
#emporary relining The a.ryli. base of an !: may be relined temporarily here loss of fit has resulted in instability or mu.osal in6ury9 Temporary relining is .arried out in the mouth using either soft or hard materials9 hen mu.osal inflammation is present) the .ushioning effe.t of the shor t$term soft materials 7tissue
.onditioners8 is an advantage in that it distributes the load more evenly and thus promotes healing9 The hard materials have been mentioned in =igure /09'9 :efore underta5ing a tempor ary reline) preparatory ad6ust ment of the denture is .ommonly ne.essary9
1
A clinical guide to removable partial dentures Figure 1$ .( /
)eporar relining
A '$a3 nost$ & al3$nat e $) press$ on t aken $n the o l' 'e nt#re $s a F #$&k an' #se%#l a$' to assess$n3 the %$t o% the 'ent#re an' $'ent$%$es press#re po$nts that reF#$re a'#st)ent *e%ore a''$n3 the rel$ne )ater$al
Figure 1$.1$ /
)eporar relining
I% the 'ent#re $s to *e rel$ne' at the &ha$rs$'e an. areas o% #n'er etens$on sho#l' %$rst *e &orre&te' *. *or'er )o#l'$n3 -$th a '$re&t appl$&at$on o% a &ha$rs$'e &ol'/r$n3 res$n Th$s res$n )a. not have a ver. stron3 *on' to the a&r.l$& 'ent#re *ase an' $% allo-e' to %or) a %eather e'3e +5 at the #n&t$on *et-een the t-o )ater$als , -$ll ten' to l$%t a%ter a per$o' o% $ntra/oral #se an' -$ll &onseF#entl. tra#)at$se the oral )#&osa Th$s $s prevente' $% a *#tt o$nt +< $s pro'#&e' *et-een the t-o res$ns
Figure 1$ . 11 -
)eporar relining
(hen &arr.$n3 o#t a '$re&t rel$ne -$th a te)porar. )ater$al $t $s all too eas. to %a$l to seat the 'ent#re &orre&tl. Th$s $s part$larl. so $n the &ase o% a )a$llar. 'ent#re I% th$s o&rs *oth the vert$&al an' the hor$ontal o&&l#sal relat$onsh$ps -$ll *e altere' It -$ll also res#lt $n th$&ken$n3 o% the &onne&tor lea'$n3 to poss$*le pro*le)s o% pat$ent toleran&e an' )a. alter the pos$t$on o% an anter$or sa''le to an #na&&epta*le 'e3ree These &han3es are l$kel. to )ake the 'ent#re #n-eara*le
Figure 1$ . 12 /
)eporar relining
There are a n#)*er o% pre&a#t$ons that &an *e taken to re'#&e the &han&e o% the 'ent#re *e$n3 seate' $n&orre&tl. In a )a$llar. 'ent#re -$th etens$ve palatal &overa3e the es&ape &hannel %or an. e&ess rel$ne )ater$al $s lon3 an' tort#o#s an' there%ore the &ho$&e o% a lov$s&os$t. )ater$al $s $)portant In the )an'$*le, an' $n $n'$v$'#al sa''les , the es&ape &hannel $s )#&h shorter an' so a h$3her v$s&os$t. )ater$al )a. *e #se'
!$
!nitial prost$etic treatment Figure 1$ . 13 / '
Alternat$v el. , -hen a l$n$n3 )ater$al o% relat$vel. h$3h/v$s&os$t. s#&h as *#t.l )etha&r.late res$n $s #se' , es&ape o% the e&ess l$n$n3 )ater$al %ro) a )a$llar. 'ent#re &an *e helpe' *. 'r$ll$n3 holes $nto the palatal &onne&tor an' so)et$)es the %lan3es
Figure 1$ . 14 /
a o 5e
5 -
s$t.
)eporar relining
I% a har' rel$ne )ater$al $s *e$n3 #se' $t $s $)portant to appre&$ate that $t )a. %lo- $nto #n'ert areas aro#n' the teeth an' that &onseF#entl. the t$)$n3 o% re)oval o% the 'ent#re %ro) t he )o#th $s &r$t$&al a$l#re to re)ove the 'ent#re *e%ore r$n3 $s &o)plete -$ll res#lt $n the 'ent#re *e$n3 lo&ke' $nto pla&e Re)oval o% the 'ent#re -$ll then onl. *e poss$*le $% the o%%en'$n3 a&r.l$& res$n $s t a-a. -$th *#rs, a thoro#3hl. t$)e/&ons#)$n3 an' %r#strat$n3 *#s$ness
Figure 1$.16 / $r e
)eporar relining
(here the loss o% %$t $s lo&al$se' to the s$te o% re&ent etra&t$ons, $t $s re&o))en'e' that the te)porar. rel$ne $s restr$&te' to that area / <5 an' << $n th$s ea)ple The re)a$n$n3 , #n)o'$%$e' $)press$on s#r%a&e helps to lo&ate the 'ent#re &orre&tl. a3a$nst the res$'#al r$'3es an' a*#t)ent teeth There -$ll *e a l$ne o% 'e)ar&at$on *et-een the ne- res$n an' the or$3$nal $)press$on s#r%a&e *#t )$nor s)ooth$n3 o% th$s #n&t$on $s all that $s #s#all. reF#$re' to a&h$eve an a&&epta*le res#lt
Figure 1$.1% /
e
)eporar relining
)eporar relining
!n&e the 'ent#re has *een rel$ne' , an. e&ess )ater$al )#st *e re)ove' %ro) the pol$she' s#r%a&es an' teeth I% the rel$n$n3 )ater$al $s a har' res$n the *or'ers are tr$))e' an' pol$she' +)a$llar. 'ent#re E&ess short/ter) so%t l$n$n3 )ater$al $s tr$))e' on the pol$she' s#r%a&e o% the 'ent#re so that the 'ent#re *or'er &ons$sts o% a s)ooth roll o% the )ater$al +)an'$*#lar 'ent#re
!3
A clinical guide to removable partial dentures Figure 1$.1! /
)eporar rel ining
A pa t$ent -ho has h a' a 'e nt#re rel$n e' -$th a shor t/ter) so%t l$n$n3 )ater$al sho#l' * e 3$ven spe&$%$& $nstr#&t$ons on ho- to &lean the l$n$n3 So)e o% these )ater$als are 'a)a3e' *. the #se o% alkal$ne per*orate 'ent#re &leansers an' others *. alkal$ne h.po&hlor$tes Unless the pat$ent $s -arne' o% these $n&o)pat$*$l$t$es rap$' 'eter$orat$on o% the l$n$n3 -$ll o&r
-s all these linings are added as a temporary measure) a posi tive de.ision must be ta5en by the dentist as to the ne*t stage of treatment9 =or e*ample) a short$term soft lining material needs
to be assessed at appro*imately ee5ly intervals and repla.ed periodi.ally until mu.osaO inflamma tion has resolved9 - ne denture .an then be .onstru.ted9
"cclusal ad;ustment Figure 1$.1" /
+cc7usa7 ad0ustent
The )ost &o))on o&&l#sal 'eter$orat$on $n 'ent#res that have *een -orn %or )an. .ears $s loss o% o&&l#sal &onta&t res#lt$n3 %ro) a &o)*$nat$on o% o&&l#sal -ear an' s$nk$n3 o% the 'ent#re %ollo-$n3 alveolar resorpt$on Corre&t$on o% the o&&l#s$on $s 'es$ra*le *e%ore &onstr#&t$n3 repla&e)ent 'ent#res as a'apt$ve )an'$*#lar post#re an' )#&osal $n%la))at$on res#lt$n3 %ro) th$s 'eter$orat$on are l$kel. to $nter%ere -$th s#&&ess%#l treat)ent
Figure 1$.1( /
+cclusal ad0ustent
A%ter the sa''les hav e *een rel$ne', o &&l#s al & onta& t &an *e r e esta*l$she' *. the a''$t$on o% tooth/&olo#re' &ol'/r$n3 a&r.l$& res$n to the poster$or teeth The %l#$' res$n $s appl$e' to the o&&l#sal s#r%a&es o% one o% the 'ent#res an' allo-e' to rea&h the 'o#3h sta3e *e%ore the 'ent#re $s $nserte' $nto the )o#th Petrole#) ell. $s appl$e' to an. oppos$n3 'ent#re teeth an' the )an'$*le $s 3entl. 3#$'e' alon3 the retr#'e' ar& o% &los#re #nt$l even o&&l#sal &onta&t $s )a'e at the appropr$ate vert$&al '$)ens$on The 'ent#re $s then re)ove' %ro) the )o#th an' the res$n allo-e' to re *e%ore re%$n$n3 the o&&l#s$on *. sele&t$ve 3r$n'$n3
!nterim prost$eses An interim prosthesis may be .onstru.ted before the definitive denture for the folloing reasons9 F 1pa.e maintenan.e and aestheti.s9
!
F Improving patient toleran.e9 F !reparation for advan.ed restorative treatment9 F Modifying 6a relationships9
!nitial prost$etic treatment Figure 1$ .2$ -
Space
aintenance and aesthetics The loss o% an anter$or tooth )a. reF#$re rap$' repla&e)ent -$th an $nter$) 'ent#re , *oth %or so&$al reasons an' to prevent re'#&t$on o% the spa&e *. 'r$%t$n3 an' t$lt$n3 o% the a'a&ent teeth
Figure 1$.21 -
Iproving patient tolerance
A s)all )$nor$t. o% pat$ents %$n' $t ver. '$%%$lt, or even $)poss$*le , to -ear a 'ent#re *e&a#se o% a prono#n&e' ret&h$n3 re%le The prov$s$on o% a th$n a&r.l$& tra$n$n3 *ase , -h$&h $n the )a$lla ) a. *e o% horseshoe 'es$3n, $s #se%#l $n over&o)$n3 the re%le The pat$ent -ears the *ase %or $n&reas$n3 per$o's ea&h 'a. #nt$l toleran&e $s 3oo' eno#3h to $n'$&ate that &onvent$onal treat)ent &an pro&ee' (hen a tra$n$n3 *ase o% horseshoe 'es$3n $s #se', the palatal etens$on &an *e $n&rease' $n sta3es to allo- pro3ress$ve a'aptat$on to palatal &overa3e -h$&h $s as &lose as poss$*le to the opt$)#) In th$s $nstan&e the tra$n$n3 *ase $n&orporates o&&l#sal &overa3e $n or'er to )o'$%. the a- relat$onsh$p $n preparat$on %or a'van&e' restorat$ve treat)ent +see *elo-
Preparation for advanced restorative treatment - fa.tor vital to the su..ess of advan.ed restorative treatment is of future treatment aims and e*pe.tations) helps to .reate a more the ability of the patient to maintain a high level of plaque .on realisti. frame of mind and readier a..eptan.e of the definitive trol9 The use of an interim prosthesis ill permit a .areful eval prosthesis9 uation of the oral and denture hygiene over a prolonged period before definitive treatment is .ommen.ed9 Modifying #a% relationships -dvan.ed prostheti. treatment .an fail be.ause of a patient
Figure 1$. << /
Modi#ing 0a/ relationships
The plann$n3 o% restorat$ons %or severel. -orn teeth $s &o)pl$&ate' *. the #n&erta$nt. as to -hether or not the $n&rease $n o&&l#sal vert$&al '$)ens$on ne&essar. to a&&o))o'ate the reF#$re' restorat$ons -$ll *e tolerate' *. the pat$ent An $nter$) prosthes$s $s &onstr#&te' to an o&&l#sal he$3ht that appears %ro) the $n$t$al assess)ent to *e appropr$ate It )a. then *e pro3ress$vel. a'#ste' over several appo$nt)ents Th$s allo-s a per$o' $n -h$&h the pat$ent &an 3ra'#all. a'apt to pro3ress$ve, )o'est $n&reases $n o&&l#sal he$3ht an' %$nall. &on%$r)s a he$3ht on -h$&h %#t#re treat)ent n$n3 &an *e *ase'
!%
A clinical guide to removable partial dentures Figure 1$.23 /
Modi#ing 0a/ relationships
An $nter$) 'en t#re &an * e help%#l $n pat$en ts eh$*$t$n 3 3$n 3$val tra#)a as a res#lt o% a 'ee p $n&$sal over*$te A s$) ple app l$a n&e -$th a pa lata l ta *le &a n p ro v$' e $nst ant rel$e% -h$le a 'e&$s$on $s *e$n3 taken on the 'e%$n$t$ve sol#t$on -hether $t *e ortho'ont$& , restorat$ve, per$o'ontal or s#r3$&al
Figure 1$.24 /
Modi#ing 0a/ relationships
In the .o#n3 pat$ent the palatal ta*le )a. also $)prove the s$t#at$on *. allo-$n3 %#rther er#pt$on o% the poster$or teeth an' &a#s$n3 so)e $ntr#s$on o% the )an'$*#lar anter$or teeth
Figure 1$.2# $ Modi#ing 0a/ relationships Prevent$on o% 3$n3$val tra#)a sho#l' not *e atte)pte' -$th an onla. appl$an&e &over$n3 onl. the poster$or teeth as &ont$n#e' er#pt$on o% the anter$or teeth )a. res#lt $n the or$3$nal tra#)at$& relat$onsh$p *e&o)$n3 re/esta*l$she'
#reatment of denture stomatitis Figure 1$.26 /
)reatent o# denture stoatitis
Dent#re sto)at$t$s $s a '$%%#se $n%la))at$on o% the 'ent#re/*ear$n3 )#&osa , o%ten o% )#lt$ple aet$olo3.
!!
!nitial prost$etic treatment The .ommonest .auses are an overgroth of the fungus Can dida albicans en.ouraged by poor denture hygiene and me.han i.al trauma from the denture9 1ystemi. .onditions) su.h as diabetes) defi.ien.ies of iron) vitamin : /2 or foli. a.id) and drug therapy) in.luding broad $spe.trum antibioti.s) steroids and
Figure 1$.2! )reatent o# denture stoatitis So)e o% the )an. aet$olo3$&al an' pre'$spos$n3 %a&tors, -h$&h )a. pla. a part $n the patho3enes$s o% 'ent#re sto)at$t$s are sho-n $n the %$3#re The poss$*le $ntera&t$on o% the var$o#s %a&tors $s &o)ple an' #n&erta$n , *#t a poss$*le s&enar$o $s as %ollo-s
.ytoto*i. agents) may predispose to denture stomatitis9 Treatment of the .ondition to a.hieve resolution of the inflammation and the asso.iated mu.osal selling should be .arried out before or5ing impressions are obtained9
A
t r a 2K / / INLAMMATI!N
)#&os a
I I
$$$
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)#&osa= th$n$t$-,an'
I , $ D Pre%= .> # 0 : petl
$9)
'ent#re plaF#e
'ent#r *ase
e
sal$var. 7 ant$/&an'$'al I ant$*o'.
s#&rose/r$&h '$et / K K .'
<
To*ins produ.ed by the Candida .ells left on the denture sur .ontribute to the .ondition by in.reasing the adhesiveness of the fa.e by defi.ient hygiene measures) together ith trauma from Candida .ells) and thus en.ouraging the formation of denture the denture) initiate an inflammatory rea.tion9 Thinning of the plaque9 -s .andidal proliferation o..urs) the rate of produ.ti on mu.osa results in in.reased permeability and es.ape of inflam of potent to*ins by the mi.ro$organisms in.reases9 The passage matory e*udate9 The e*udate) together ith desquamated of these to*ins into the tissues is fa.ilitated by the thinning and mu.osal .ells) forms a favourable nutrient medium) hi.h pro in.reased permeability of the mu.osa9 -ggravation of the inflam motes the groth of Candida albicans. In addition) this e*udate) matory response o..urs and so a vi.ious .ir.le is set up9 -nti and the su.rose$ri.h diet hi.h may result from the dietary sele. .andidal antibody is se.reted in parotid saliva but the denture tion sometimes asso.iated ith the earing of dentures) may base may restri.t a..ess of antibody to the Candida .ells9
Figure 1$.2" /
)reatent o# denture stoati tis
The aet$olo3$&al %a&tors )a. a&t alone or $n &o)*$nat$on as $n'$&ate' here '$a3ra))at$&all. In pat$ent +5 the les$on $s '#e to a prol$%erat$on o% ,andida or3an$s)s, $n pat$ent +< to 'ent#re tra#)a, an' $n pat$ent +> to a &o)*$nat$on o% these %a&tors The pos$t$on o% ea&h 'ent#re sto)at$t$s pat$ent sho#l' *e est$)ate' on th$s aet$olo3$&al s&ale so that the appropr$ate treat)ent &an *e &arr$e' o#t
$
?
1
candida trauma system ic factors
Figure 1$.2( /
)reatent o# denture sto atitis
I% the 'ent#re plaF#e &ontrol $s poor the 'ent$st sho#l' 'e)onstrate the plaF#e to the pat$ent *. the #se o% a '$s&los$n3 sol#t$on, epla$n the s$3n$%$&an&e o% the plaF#e an' 3$ve $nstr#&t$on $n ho- *est to re)ove $t
?
3
67
A clinical guide to removable partial dentures Figure 1$ .3$ /
)reatent o# denture stoatitis
To &lean the 'ent#re the pat$ent s ho#l' *e a'v$se' to #se a s)all hea'e' )e'$#) )#lt$/t#%te' tooth*r#sh, -h$&h 3$ves 3oo' a&&ess to all parts o% the 'ent#re an' 3oo ' a'apta*$l$t. to the s#r%a&e An. a3ent #se' -$th the *r#sh sho#l' have a lo- a*ras$v$t. %or a&r.l$& res$n Soap $s one s#&h a3ent It sho#l' *e note' that )an. propr$etar. toothpastes , an' even so)e 'ent#re pastes , &onta$n a*ras$ve part$&les -h$&h &an 'a)a 3e a&r.l$& res$n
Figure 1$ .31 -
)reatent o# denture stoatitis
A&r.l$& 'ent#res sho#l' also *e $) )erse ' 'a$l . $n a &leans er o% the h.po&hlor$te t.pe, as these hav e *een sho-n to *e the )ost e%%e&t$ve &he)$&al a3ents %or plaF#e re)oval In th$s %$3#re an a&r.l$& plate &arr.$n3 '$s&lose' plaF#e has *een part$all. $))erse' %or <0 )$n#tes $n s#&h a &leanser , r$nse' an' then re/'$s&lose' The $))erse' port$on +r$3ht s$'e has *een ren'ere' plaF#e/%ree
@ Figure 1$ .32 /
)reatent o# denture stoatitis
Co*alt &hro)$#) 'ent#res sho#l' not *e $))erse' %or lon3 per$o's $n h.po&hlor$te &leansers *e&a#se there $s a r$sk o% &orros$on o% the )etal
I % trauma appears to be a .ontributory fa.tor to the stomati I % the lesion does not respond to these lo.al measures the inves tis) appropriate ad6ustments ) su.h as o..lusal .orre.tion and tem tigation of possible systemi. fa.tors shoul d be undert a5en9 In porary relining) should be made to the denture as des.ribed in su.h refra.tory .ases) oral antifungal agents su.h as -mpho the earlier se.tions of this .hapter9 ;oever) it should be borne teri.in :) Nystatin or Mi.ona>ole may be benefi.ial9 I t should in mind that as temporary linings ith tissue .onditioners ma5e be noted) hoever) that these antifungal agents by themselves are it more diffi.ult for the patient to 5eep the denture .lean) they of very limited value and unless the underlying .ause of the should be avoided if possible9 -s both plaque and traumati. fa. den ture stomatitis is eradi.ated the .ondition ill re.ur hen tors .an be eliminated by leaving the denture out the patient the antifungal agents are ithdran9 should be advised to do this as mu.h as possible9
68
4urgery
urgery may be ne.essary prior to !" .onstru.tion remove retained roots or unerupted teeth) hi.h are super to
S
fi.ially lo.ated in edentulous areas) and to eliminate pathology asso.iated ith teeth or dental remnants9 I t may also any
be ne.essary to improve the .ontours of edentulous areas by redu.ing bony prominen.es and hyperplasti. soft tissue) and to eliminate prominent fraenal atta.hments9
Figure 11.1 Th$s ra'$o3raph reveals that an #ner#pte' se&on' pre)olar has $n%l#en&e' the al$3n)ent o% the %$rst pre)olar, -h$&h $s t$lte' '$stall. an' $s #ns#$ta*le %or #se as an a*#t)ent I% $t $s 'e&$'e' that an RP! sho#l' *e prov$'e' $t -$ll *e ne&essar. to &ons$'er re)oval o% *oth teeth
Figure 11.2 A th$r ' ) olar er#pt$n 3 at s#&h an #n %avo#ra* le an3le -$ll not prov$'e a&&epta*le s#pport %or an RP! an' -$ll prevent %#ll etens$on o% the '$stal etens$on sa''le It sho#l' *e re)ove' pr$or to 'ent#re &onstr#&t$on
69
A clinical guide to removable partial dentures Figure 11.3 Pro)$nent )an'$*#lar tor$ &onst$t#te an o*str#&t$on to the $nsert$on o% an RP! %ra)e-ork an' to the &orre&t lo&at$on o% a l$n3#al &onne&tor S#r3$&al re'#&t$on $s a relat$vel. s$)ple pro&e'#re
Figure 11.4 B#l*o#s an' )o*$le t#*eros$t$es prov$'e poor s#pport %or RP! sa''les an' )a. also &reate pro*le)s $n the or$entat$on o% the o&&l#sal plane S#r3$&al re'#&t$on -$ll $)prove the &onto#r an' &ons$sten&. o% the so%t t$ss#es
Figure 11.% The prolon3e' -ear$n3 o% an #nsat$s%a&tor. 'ent#re has &a#se' th$s lo&al$se' area o% so%t t$ss#e h.perplas$a The t$ss#e )#st *e re)ove' *e%ore a ne- 'ent#re $s &onstr#&te' The e&$se' p$e&e o% so%t t$ss#e sho#l' *e sent %or h$stopatholo3$&al ea)$nat$on S#r3er. $s &learl. $n'$&ate' $n th$s $nstan&e (here a les$on $s asso&$ate' -$th the %lan3e o% a 'ent#re , the %lan3e sho#l' *e t *a&k to allo- resol#t$on o% the $n%la))at$on *e%ore the nee' %or s#r3er. $s assesse'
70
1-
Periodontal treatment
umerous studies have demonstrated that the earing of !"s ill tend to en.ourage the a..umulation of plaque9
Clures so that the a..umulation of plaque around abutment teeth and !" .omponents is 5ept to a minimum9 -ll patients ill therefore require oral hygiene instru.tion and I t is important to establish a .ondition of health in the periodontal tissues prior to prostheti. treatment and to ensure many ill also need basi. periodontal treatment9 More e*tensive that patients re.eive detailed instru.tion in oral hygiene pro.e$ pro.edures may also be required on some o..asions9
N
Figure 12 . 1 Even $n a s#per%$&$all. &lean )o#th the -ear$n3 o% an RP! $s o%ten asso&$ate' -$th so)e 'e3ree o% 3$n3$val an' )#&osa= $n%la))at$on Lo&al$se' $n%la))ator. &han3es o% th$s t.pe -$ll #s#all. resolve $% the level o% plaF#e &ontrol an' 'ent#re h.3$ene &an *e $)prove'
Figure 12.2 Th$s a&r.l$& RP! , -h$&h repla&es t-o )a$llar. $n&$sors , 5< an' 55, has etens$ve an' #nne&essar. &overa3e o% palatal 3$n3$val )ar3$ns
@5
A clinical guide to removable partial dentures Figure 12.3 Re)oval o% the 'ent#re reveals -$'esprea' )ar3$nal 3$n3$v$t$s an' so)e 'e3ree o% $n%la))at$on o% the palatal )#&osa The 3$n3$val )ar3$ns sho#l' *e epose' , e$ther *. )o'$%.$n3 the e$st$n3 'ent#re or *. prov$'$n3 an $nter$) prosthes$s PlaF#e &ontrol $s then l$kel. to *e )ore e%%e&t$ve an' the &on'$t$on sho#l' resolve pr$or to the &onstr#&t$on o% a -ell/'es$3ne' &o*alt &hro)$#) RP!
Figure 12.4 In &ontrast to the pat$ent $n $3#re 5<>, there has *een so )#&h $n%la))at$on an' so%t t$ss#e 'a)a3e $n th$s )o#th that $)prove)ent $n oral an' 'ent#re h.3$ene $s #nl$kel. to a&h$eve resol#t$on The 3$n3$val t$ss#es -$ll nee' to *e re&onto#re' s#r3$&all. pr$or to the &onstr#&t$on o% a repla&e)ent RP!
Figure 12.% Here the $n%la))ator. &han3es a%%e&t$n3 the palatal 3$n3$val t$ss#es #n'er a s#&&ess$on o% )#&osa/*orne RP!s have pro'#&e' so)e 'e3ree o% h.pertroph. -$th po&ket$n3 an' an #n%avo#ra*le t$ss#e )orpholo3.
Figure 12.6 A 3$n3 $ve&t o). has *een # n'ert aken to $)pro ve th e so% t t$ss #e &onto#rs , the stan'ar' o% oral h.3$ene has *een 3reatl. $)prove' an' a tooth/s#pporte' &o*alt &hro)$#) RP!, $n&orporat$n3 3enero#s &learan&e o% the 3$n3$val )ar3$ns, has *een prov$'e'
72
Periodontal treatment
Figure 12.la
Figure 12.l b
The etent an' '$str$*#t$on o% the e'ent#lo#s spa&es $n th$s )o#th )akes $t '$%%$lt to avo$' so)e coverage o% 3$n3$val )ar3$ns an' th$s pat$ent has -orn a s#&&ess$on o% a&r.l$& RPDs -$th %#ll palatal &overa3e The $nter$) 'ent#re sho-n here has re'#&e' 3$n3$val coverage to a )$n$)#)
Re)oval o% the 'ent#re reveals that the health o% the 3$n3$val t$ss#e has $)prove' an' that there $s no- onl. a ver )$l' 'e3ree o% $n%la))at$on a%%e&t$n3 the )#&osa $n the palatal va#lt
Figure 12 ." H.pertroph. o% the 3$n3$val t$ss#es , ho-ever , has le' to coverage o% )ost o% the palatal aspe&t o% the &ro-n o% <@ an' $% th$s tooth $s to serve as an a*#t)ent %or an $)prove' 'es$3n o% RP! , $t -$ll *e ne&essar. to #n'ertake 3$n3$ve&to). to epose the anato)$&al &ro-n The 'e%e&t$ve restorat$on $n <; -$ll, o% &o#rse , also reF#$re to *e repla&e'
Figure 12 .( Th$s pat$ent has -orn a )#&osa/*orne RP! $n the )an'$*le -$th a&r.l$& '$stal etens$on sa''les an' a sta$nless steel l$n3#al *ar &onne&tor Th$s $na'eF#ate prosthes$s has &a#se' &ons$'era*le 'a)a3e to the 3$n3$val t$ss#es aro#n' ;: an' >;, str$pp$n3 the) a-a. %ro) the '$stal an' l$n3#al aspe&ts o% these a*#t)ent teeth Depos$ts o% s#pra/ an' s#*3$n3$val &all#s are present an' ;: sho-s $n&rease' )o*$l$t. It $s $)portant to eval#ate -hether or not the 3$n3$val t$ss#es &an *e restore' to a &on'$t$on o% health an' -hether these teeth nohave s#%%$&$ent $nvest$n3 *one to &ontr$*#te to the s#pport o% an RP! %ra)e-ork
73
13 0
"rt$odontic treatment
rthodonti. treatment has some benefits to offer hen !"s ar e required and the spa.e available for the pros
thesis has be.ome restri.ted due to movement of the ad6a.ent teeth 9 This may happen hen some of the permanent
teeth fail to develop or erupt) or hen the presen.e of an unre stored edentulous gap has alloed some drifting and tilting of the abutments to ta5e pla.e 9
Figure 13.1 In th$s $nstan&e , a*sen&e o% the per)anent )a$llar. lateral $n&$sors, to3ether -$th earl. loss o% <5 , has allo-e' the re)a$n$n3 &entral $n&$sor to 'r$%t a&ross the )$'l$ne Prosthet$& treat)ent has not a&h$eve' a sat$s%a&tor. aesthet$& res#lt
Figure 13.2 The reta$ne' 'e&$'#o#s &an$ne has *een etra&te' an' a re)ova*le ortho'ont$& appl$an&e has *een #se' to retra&t 55 an' *r$n3 $t $nto a )ore a&&epta*le al$3n)ent
75
A clinical guide to removable partial dentures Figure 13.3 The la*$al an' $n&$sal s#r%a&es o% 5> an' 55 have *een re&onto#re' an' an RP! has *een prov$'e' to pro'#&e a )ore a&&epta*le appearan&e #rther ortho'ont$& treat)ent $s no- propose' $n or'er to real$3n the )an'$*#lar 'ent$t$on
Figure 13.4 La&k o% a prosthet$& repla&e)ent %or )$ss$n3 poster$or teeth has allo-e' th$s )an'$*#lar )olar to t$lt )es$all. In th$s pos$t$on $t not onl. o%%ers less than a'eF#ate s#pport %or an RP! *#t also &reates pro*le)s $n the )a$ntenan&e o% an a'eF#ate stan'ar' o% oral h.3$ene
Figure 13.% !rtho'ont$& treat)ent has re/esta*l$she' spa&e *. #pr$3ht$n3 the tooth It has also pro'#&e' an a*#t)ent tooth that $s %avo#ra*l. pos$t$one' to prov$'e e%%e&t$ve s#pport an' retent$on %or an RP! %ra)e-ork
There are times hen it is ne.essary to provide permanent retention of teeth folloing orthodonti. treatment and this may
76
involve the use of an !"9 It is usually more appropriate) ho ever) to use fi*ed retainers for this purpose9
1
onservative
onservative treatment ill ne.essarily pre.ede the .on
master impressions are re.orded9 In this ay it should be pos sible to ensure that the a..urate fit of the .omponents of the !" against theofabutment is maintained throughout the stru.tion denturesteeth in order to ensure that the .lini.al life of the denture9 There are fe pro.edures more frustrating than to embar5 .onservative treatment of teeth before to hi.h an integrity of theonremaining teeth is established
C
!" frameor5 has already been fitted9 In many .ases) requirements of the !" design su.h as sup por t) retention and bra.ing ill ne.essitate modifi.ation of tooth surfa.es and the details of su.h tooth preparations are presented in hapter /#9 =req.rently) hoever) these fa.tors also di.tate the form of individual restorations9 It is therefore essen tial that a provisional denture design is established before details of .onservative treatment are finalised9
Figure 14.1 It $s part$larl. $)portant that teeth -h$&h are to serve as a*#t)en ts %or an RP! sho#l' *e &are%#ll. eval#ate' Here, 59 has a'van&e' &ar$es o% the &ro-n str#&t#re It $s $)portant to as&erta$n -hether or not $t $s v$tal an' , $% non/v$tal , to assess -hether $t has *een , or &an *e, a'eF#atel. root/treate' It $s also &r$t$&al to ens#re that the &oronal str#&t#re &an *e so#n'l. restore' I% the lon3/ter) pro3nos$s $s 'o#*t%#l $t )a. *e -$ser to &ons$'er etra&t$on an' $n&orporat$on -$th$n the RP!
Figure 14.2 (here the nee' %or etens$ve restorat$on /o% a tooth #st$%$es the %$tt$n3 o% a %#ll veneer &ro-n, the opport#n$t. sho#l' *e taken to $n&orporate +5 3#$'e s#r%a&es, +< retent$ve #n'erts an' +> rest seats $nto the &ro-n These )o'$%$&at$ons -$ll #s#all. *e &arr$e' o#t at the -a$n3 /#p sta3e o% &ro-n &onstr#&t$on an' -$ll *e pro'#&e' *. &are%#l shap$n3 o% the -a pattern on the s#rve.or Ho-ever, $t )#st *e re)e)*ere' -hen prepar$n3 the tooth that s#%%$&$ent tooth str#&t#re )#st *e re)ove' to allo- these %eat#res to *e $n&l#'e' -$th$n the *#lk o% the restorat$on
2
" "
A clinical guide to removable partial dentures Figure 14.3 The *#&&al sp o% ;: has re&entl . %ra&t#re' an' the tooth has *een restore' -$th a lar3e , p$nne' a)al3a) restorat$on I% $t $s no- to serve as an RPD a*#t)ent there $s a r$sk o% %ra &t#re o% the tooth or restorat$on, %ro) the a''$t$onal loa' trans)$tte' *. the 'ent#re &o)ponents or th$s reason $t -$ll *e restore' -$th a %#ll veneer &ro-n
Figure 14.4 The &o)plete' restorat$on $n&orporates a seat %or an o&&l#sal rest that -$ll prov $'e s#pport %or an RPD
Figure 14.% #ll veneer &ro-ns have *een #se' to re'#&e the 'e3ree o% #n'ert on the *#&&al aspe&t o% these t-o )a$llar. )olars , an' to prov$'e a )ore %avo#ra*le s#rve. l$ne %or &lasp$n3
Figure 14.6 In the )an'$*le, the nee' $s )ore %reF#entl. to )o'$%. l$n3#al &onto#rs Here a &ro-n has *een #se' to re'#&e an e &ess$ve l$n3#al #n'ert an' th#s pro'#&e a )ore %avo#ra*le shape %or &lasp$n3 A s$) $lar pr o& e'# re )a . o n o && as$ on *e ne& es sa r. on l$n3#all. t$lte' )olars or pre)olars , -h$&h -o#l' other-$se prevent the $nsert$on o% a l$n3#al &onne&tor
78
onservative treatment Figure 14.! A ) an'$*# lar pre)o lar -$th an #nsat$s %a&tor. s#rve . l$ne has *e en restore' -$th a %#ll veneer &ro -n that prov$'es an a&&epta*le 'e3ree o% #n'ert %or a 3$n3$vall. approa&h$n3 2I2 *ar &lasp G#$'e s#r%a&es have also *een esta*l$she' to 'eter)$ne the path o% $nsert$on an' re)oval o% the RP! %ra)e-ork an' to prov$'e re&$pro&at$on %or the retent$ve &lasp ar)
79
1/ p
#oot$ preparation
reparation may be underta5en for a number of reasons9
!rovide rest seats9 F @stablish guide surfa.es9 F Modify unfavourable survey lines9 F reate retentive areas9 In addition) o..lusal ad6ustment may also form an importan t part of toot h preparation 7see =igures '9/4) '9/# and '9/'89 Tooth preparation for !"s should be planned on arti.ulated study .asts after they have been surveyed and a denture design produ.ed9 1haping of enamel surfa.es for any of the reasons listed is usu$
Figure 1%.1 /
ally underta5en ith rotary diamond instruments of appropri ate si>e and shape9 The resulting roughened enamel surfa.e must alays be smoothed and polished9 1pe.ial burs) stones and abra sive$impregnated rubber heels and points are available for this purpose9 1ubsequent appli.ation of a topi.al fluoride varnish) to redu.e the .han.e of .arious atta.5 of the modified enamel sur fa.es) should be .arried out routinely9
'est seats est seats may need to be prepared to( F produ.e a favourable too th surfa.e for suppor t 7=igure /#9/8B F prevent interferen.e ith the o..lusion 7=igure /#928B F redu.e the prominen.e of a rest 7=igure /#9389
est seats
A rest pl a&e' o n an $n&l$ne' s#r%a&e -$ll ten' to sl$'e 'o-n the tooth #n'er the $n%l#en&e o% o&&l#sal loa's +5 The res#lt$n3 hor$ontal %or&e )a. &a#se a l$)$te' la*$al )$3rat$on o% the tooth -$th %#rther loss o% s#pport %or the 'ent#re The prov$s$on o% a rest seat +< -$ll res#lt $n a vert$&al loa'$n3 o% the tooth , )ore e%%$&$ent s#pport an' a*sen&e o% tooth )ove)ent
1
Figure 1%.2 /
-
est seats
An o& &l#sal rest pla&e' at the arro- $n 7/8 -o#l' &reate a pre)at#re o&&l#sal &onta&t +<, #nless a rest seat -as prepare' to )ake roo) %or $t +> Spa&e %or the rest sho#l' not #s#all. *e &reate' *. 3r$n'$n3 the )an'$*#lar *#&&al sp as th$s $s a s#pport$n3 sp &ontr$*#t$n3 to the sta*$l$t. o% the $nterspal pos$t$on
1
-
3 85
A clinical guide to removable partial dentures
$
Figure 1%.3 /
est seats
In a''$t$on, a rest pla&e' on an #nprepare' tooth s#r%a&e +5 -$ll stan' pro#' o% that s#r%a&e an' )a. ten' to &olle&t %oo' part$&les an' poss$*l. &reate '$%%$lt$es $n tolerat$n3 the 'ent#re The preparat$on o% a rest seat +< -$ll allo- the rest to *e shape' so that $t *len's $nto the &onto#r o% the tooth, $s less apparent to the pat$ent an' also har)on$se s -$th the o&&l#sal relat$onsh$p
1
3
$
Figure 1%.4 /
est seats on posterior teeth
The 'es$3n o% rest seats on poster$or teeth $s sho-n $n 5o&&l#sal v$e- <)es$o'$stal v$e- > pro$)al v$e- It -$ll *e seen that preparat$on $nvolves a re'#&t$on $n the he$3ht o% the )ar3$nal r$'3e $n or'er to ens#re an a'eF#ate *#lk o% )ater$al l$nk$n3 the o&&l#sal rest to the )$nor &onne&tor Rest seats on poster$or teeth sho#l' nor)all. *e sa#&er/shape' so that a &erta$n a)o#nt o% hor$ontal )ove)ent o% the rest -$th$n the seat $s poss$*le D$ss$pat$on o% so)e o% the ener3. 'evelope' *. o&&l#sal %or&es a&t$n3 on the 'ent#re &an then o&r
Figure 1%.# $ est seats on posterior teeth The #se o% a *o /shape' rest seat -$th$n a &ast restorat$on )a. res#lt $n the rest appl.$n3 'a)a3$n3 hor$ontal loa's on the a*#t)ent tooth These rest seats sho#l' *e restr$&te' to tooth /s#pporte' 'ent#res -here the per$o'ontal health o% the a*#t)ent teeth $s 3oo'
Figure 1%.6 /
est seats on posterior teeth
The rest sho#l' *e at least 5 )) th$&k %or a'eF#ate stren3th To &he&k that s#%%$&$ent ena)el has *een re)ove' '#r$n3 rest seat preparat$on to a&&o))o'ate th$s th$&kness o% )etal , the pat$ent sho#l' *e aske' to o&&l#'e on a str$p o% so%tene' p$nk -a The th$&kness o% -a $n the re3$on o% the rest seat -$ll $n'$&ate $% a'eF#ate &learan&e has * een a&h$eve'
"$
#oot$ preparation
Figures 1%.! and 1%." /
est seats on posterior teeth
(here a &lasp $s to eten' *#&&all. %ro) an o&&l#sal rest an' there $s no spa&e o&&l#sall. %or $t to 'o so , the preparat$on )#st *e eten'e' as a &hannel on to the *#&&al s#r%a&e o% the tooth In so)e &$r)stan&es $t )a. also *e ne&essar. to re'#&e an' re&onto#r the sp o% the tooth $n the oppos$n3 ar&h
!est seats on anterior teeth The design of rest seats on ant erior teeth is shon in =igures /#9, to /#9/29
Figure 1% .( /
est seats on anterior teeth
!n )a$llar. anter$or teeth, part$larl. &an$nes , the &$n3#l#) $s o%ten -ell eno#3h 'evelope' so that )o'est preparat$on to a&&ent#ate $ts %or) &reates a rest seat -$tho#t penetrat$on o% the ena)el
Figure 1%.1$ /
est seats on anterior teeth
A &.l$n 'r$&a l '$a )on' stone -$th a ro# n'e' t$p sh o#l' *e #se' to prepare the rest seat A spher$&al $nstr#)ent ten's to &reate #n-ante' #n'erts
l
83
A clinical guide to removable partial dentures
1
t
Figure 1% . 11 -
est seats on anterior teeth
The l$n3#al s#r%a&e o% a )an'$*#lar anter$or tooth $s #s#all. too vert$&al an' the &$n3#l#) too poorl. 'evelope' to allo- preparat$on o% a &$n3#l#) rest seat -$tho#t penetrat$on o% the ena)el ln&$sal rest seats there%ore have a -$'er appl$&at$on $n th$s s$t#at$on, $n sp$te o% the$r $n%er$or appearan&e The preparat$on $s sho-n %ro) the la*$al +5 , l$n3#al +< an' pro$)al +> v$e-po$nts
Figure 1%.12 /
est seats on anterior teeth
ln&$sal rest seats &an *e prepare' #s$n3 a tapere' &.l$n'r$&al '$a)on' Alternat$ve, )ore aesthet $&, opt$ons are to pro'#& e a rest seat $ n &o)pos$te appl$e' to the &$n3#l#) area o% the sele&te' tooth , or to *on' a &ast )etal &$n3#l#) rest seat to the tooth
uide surfaces Figure 1%.13 /
;uide sur#aces
G#$'e s#r%a&es +J are t-o or )ore parallel a$al s#r%a&es on a*#t)e nt teeth , -h$&h l$)$t the path o% $nsert$on o% a 'ent#re G#$'e s#r%a&es )a. o&r nat#rall. or , as $s )ore o%ten the &ase, )a. nee' to *e prepare'
The advantages of guide surfaces I t is idely a..epted on the basis of .lini.al observation that the utilisation of guide surfa.es .onfers a number of benefits in !" .onstru.tion9 The benefits in.lude the folloing(
F In.reased stability9 F e.ipro.ation9 !revention of .lasp deformation9 F Improved appearan.e9
Figure 1% . 14 /
Increased stabilit
Th$s $s a&h$eve' *. the 3#$'e s#r%a&es res$st$n3 '$spla&e)ent o% the 'ent#re +re' arro-s $n '$re&t$ons other than alon3 the planne' path o% '$spla&e)ent
84
#oot$ preparation Figure 1% . 1% /
eciprocation
A 3#$'e s#r%a&eJ allo-s a re&$pro&at$n3 &o)ponent to )a$nta$n &ont$n#o#s &onta&t -$th a tooth as the 'ent#re $s '$spla&e' o&&l#sall. The retent$ve ar) o% the &lasp $s th#s %or&e' to %le as $t )oves #p the tooth It $s th$s elast$& 'e%or)at$on o% the &lasp that &reates the retent$ve %or&e +Chapter @, A ,linical ;uide to eovable Partial 'enture 'esign:.
Figure 1%.16 /
Prevention o# clasp de#oration
G#$'e s#r%a&es ens#re that the pat$ent re)oves the 'ent#re alon3 a planne' path +5 The &lasps are there%ore %lee' to the etent %or -h$&h the. -ere 'es$3ne' ($tho#t 3#$'e s#r%a&es the pat$ent ) a. t$lt or rotate the 'ent#re on re)oval +< , &a#s$n3 &lasps to %le *e.on' the$r proport$onal l$)$t
Figure 1%.1! /
A I I
1
$
I
A
,, I
Iproved appearance
A 3# $'e s# r%a&e on an anter$or a*#t)ent tooth per)$ts an $nt$)ate &onta&t *et-een sa''le an' tooth -h$&h allo-s the one to *len' -$th the other , &reat$n3 a &onv$n&$n3, nat#ral appearan&e G#$'e s#r%a&es )a. o&r nat#rall. $n th$s s$t#at$on an' $% so , tooth preparat$on $s not reF#$re'
The preparation of guide surfaces uide surfa.es are usually prepared) somehat impre.isely) by the guide surfa.es .he.5ed using the analysing rod9 I % .orre.tion eye9 The position in hi.h the h/ndple.e must be held to pre is found to be needed) further intra$oral ad6ustment .an pare the required guide surfa.es) so that they are all parallel to be underta5en9 ea.h other and to the path of insertion) should be established on - more pre.ise approa.h to the preparation of guide surfa.es the study .ast9 .an be a.hieved by the use of 6igs .onstru.ted on a prepared -s a .he.5 on the a..ura.y of the prepared guide surfa.e) an study .ast and then transferred to the mouth) either to .ontrol the alginate impression may be ta5en to produ.e a se.ond study .ast9 posi This .ast .an then be pla.ed on a surveyor and the parallelism of tioning of the handpie.e or to .he.5 on the lo.ation and amount of enamel redu.tion9
SS
A clinical guide to removable partial dentures Figure 1% . 1" /
)he preparation o# guide sur#aces
A 3#$ 'e s# r%a&e sho#l' eten' vert$&all. %or a*o#t > )) an' sho#l' *e kept as %ar %ro) the 3$n3$va ) ar3$n as poss$*le
Figure 1%.1( /
)he preparation o# guide sur#aces
A 3#$' e s# r%a&e sho#l' *e pro '#&e' *. re) ov$n 3 a )$n$) al an ' %a$rl. #n$%or) th$&kness o% ena)el , #s#all. not )ore than 0: )), %ro) aro#n' the appropr$ate part o% the &$r)%eren&e o% the tooth +3reen area The s#r%a&es sho#l' not *e prepare' as a %lat plane, as -o#l' ten' to o&r $% an a*ras$ve '$s& -ere #se' +re' area Th$s $s #nne&essar$l. 'estr#&t$ve an' )a. even lea' to penetrat$on $nto 'ent$ne , th#s )ak$n3 a restorat$on o*l$3ator.
Figure 1%.20 $
)hepreparation o# guide sur#aces
The reF#$re' lo&at$on o% a 3#$'e s#r%a&e -$ll *e 'epen'ent on $ts %#n&t$on The re' 3#$'e s#r%a&es on the pr o$)al s#r%a&es o% the a*#t)ent teeth %a&$n3 the e'ent#lo#s spa&e -$ll *e nee'e' to &ontrol the path29% $nsert$on o% the sa''le The 3reen 3#$'e s#r%a&es on the tooth s#r%a&es '$a)etr$&all. oppos$te the retent$ve port$on o% the &lasp -$ll *e nee'e' %or the latter2s re&$pro&at$on
?n#avourable surve lines
A h$3h s #rv e. l$ne on a t ooth that $s to *e &l aspe ' $s #n %avo #ra*l e *e&a#se $t reF#$res the &lasp to *e pla&e' too &lose to the o&&l#sal s#r%a&e an' )a. &reate an o&&l#sal $nter%eren&e +arro-sEven $% an
86
o&&l#sal $nt er%eren&e $s not present, a h$3h &lasp ar) $s )ore not$&ea*le to the pat$ent an' )a. $nter%ere -$th )ast$&at$on
#oot$ preparation Figure 1%.23 -
?n#avourable surve lines
+5A h$3h s#rve. l$ne )a. also res#lt $n 'e%or)at$on o% the &lasp *e&a#se , on $nsert$on , the &lasp $s prevente' %ro) )ov$n3 'o-n the tooth *. &onta&t -$th the o&&l#sal s#r%a&e I% the pat$ent pers$sts $n tr.$n3 to seat the 'ent#re, the &lasp $s *ent #p-ar's rather than %lee' o#t-ar's +<Shap$n3 the ena)el to lo-er the s#rve. l$ne -$ll allo- the &lasp to *e pos$t$one' %#rther 3$n3$vall. an' $t also prov$'es a 2lea'/$n2 '#r$n3 $nsert$on, &a#s$n3 the &lasp to %le o#t-ar's over the s#rve. l$ne as planne'
I
1
$
I
2
'etentive areas Figure 1%.24 /
etentive areas
Retent$ve areas &an *e &reate' *. 3r$n'$n3 ena)el Ho-ever , the ena)el $s relat$vel. th$n $n the 3$n3$val th$r' o% t he &ro-n -here the retent$ve t$p o% the &lasp -o#l' nor)all. *e pla&e' , so the a)o#nt o% #n'ert that &an *e a&h$eve' *. these )eans -$tho#t penetrat$n3 the ena)el $s str$&tl. l$)$te' It $s #s#all. *etter to esta*l$sh $)prove' &onto#rs %or retent$on *. restorat$ve )etho's as o#tl$ne' $n Chapter 5;
Figure 1%.2% /
etentive areas
Un'ert areas &an also *e &reate' *. the #se o% a&$'/et&h &o)pos$te restorat$ons A * roa' area o% atta&h) ent o% the restorat$ on to t he ena )el $s 'es$ra*le as th$s -$ll re'#&e the &han&e o% the restorat$on *e$n3 '$spla&e' an' -$ll pro'#&e a &onto#r )ore s#$ta*le %or &lasp$n3 The earl. &o)pos$tes -ere not s#$ta*le %or th$s p#rpose as the. &onta$ne' &oarse %$ller part$&les that &a#se' )arke' a*ras$on o% the &lasp ar) -$th &onseF#ent -eaken$n3 o% the &lasp an' loss o% retent$on Ho-ever, the #se o% )o'ern #ltra%$ne an' h.*r$' &o)pos$tes res#lts $n )$n$)al )#t#al a*ras$on o% &o)pos$te an' & lasp so that the te&hn$F#e $s a '#ra*le, e%%e&t$ve an' &onservat$ve )etho' o% enhan&$n3 RP! retent$on
87
Part 3 Prost$etic treatment n this part e .onsider the .lini.al pro.edures involved in the .onstru.tion of remov
I
e*penen.e9
able partial dentures9 The various .hapters offer only a basi. guide to these pro.edures
as e believe that the details of te.hnique .an be learnt only by .lini.al tuition and
89
=or>ing impressions
(
or5ing impressions are obtained after the denture has been designed and any tooth preparation .ompleted9
!ndividual tray
The produ.tion of a or5ing .ast suffi.iently a..urate for the .onstru.tion of an !" frequently ne.essitates the use of an indi It should be realised that even in the absen.e of obvi ous mu.osaO in6ury) an e*isting denture ill have had a signifi vidual tray9 1u.h a tray enables an a..urate impression to be .ant influen.e on the form of the denture$bearing made of the fun.tional depth and idth of the sul.i $n those mu.osa9 e.overy of the mu.osa after removal of the denture .an areas that ill be related to the denture border and to ta5e sev eral hours9 Therefore a patient should be advised to leave .omponent s su.h as gingivally approa.hing .lasps) .onne.ting the den ture out for at least four hours before attending for the bars and plates9 or5ing impression 9 There ill) of .ourse) be some patients ho are unable to .omply ith this advi.e for so.ial reasons9
Figure 16.1 /
Individual tra
In or'er to pro'#&e an a&rate $)press$on, the tra. sho#l' *e &onstr#&te' so that $t $s #n$%or)l. spa&e' %ro) the teeth an' a'a&ent t$ss#es Th$s -$ll prov$'e %or the la.er o% $)press$on )ater$al o% #n$%or) an' s#%%$&$ent th$&kness ne&essar. %or opt$)#) elast$& re&over. on re)oval %ro) the )o#th
Figure 16 .2 /
Individual tra
In'$v$'#al tra.s are #s#all. )a'e %ro) &ol' /r$n3 or l$3ht re' a&r.l$& res$n -$th a h$3h %$ller &ontent The tra. )ater$al $s a&ratel. )o#l'e' over a -a spa&er >)) $n th$&kness The *or'ers are tr$))e' #nt$l the. are s)ooth an' lo&ate' #n$%or)l. <)) short o% the 'epth o% the s#l&$ Th$s -$ll prov$'e s#%%$&$ent s#pport %or the $)press$on )ater$al -h$le allo-$n3 #nrestr$&te' )ove)ent o% the a'a&ent t$ss#es '#r$n3 *or'er )o#l'$n3
75
A clinical guide to removable partial dentures Figure 16.3 /
Individual tra
R$3$'$t. o% the tra. $s $)portant There%ore, -here t he 2U2 &ross se&t$onal shape $s la&k$n3 , K as )a. o&r $n resor*e' e'ent#lo#s areas , the tra. sho#l' *e st$%%ene' *. the a''$t$on to $ts eternal s#r%a&e o% a %$n o% a&r.l$& tra. )ater$al, as $n'$&ate' *. the arro- The %$n has the a''$t$onal *ene%$t o% prov$'$n3 a %$n3er rest -hen the tra. $s hel' $n pos$t$on -h$le the $)press$on $s o*ta$ne' A%t er &o nst r#& t$o n , the tra. )#st *e set as$'e %or a*o#t 50 ho#rs to rea&h a sta*le state I% #se' $))e'$atel., the stresses *#$lt $nto the tra. '#r$n3 the )o#l '$n3 o% the )ate r$al -$ll st$ll *e #n'er3o$n3 rel$e% , th#s re'#&$n3 the a&ra&. o% the $)press$on
#$e use of stops Figure 16.4 /
)he use o# stops
StopsJ on the $nternal s#r%a&e o% the $)press$on tra. )a$nta$n the $nten'e' spa&$n3 %or the $)press$on )ater$al The. also per)$t the tra. to *e ret#rne' to the sa)e pos$t$on ea&h t$)e $t $s $nserte' $nto the )o#th, -h$&h allo-s the *or'ers to *e a&ratel. tr$))e' to the$r &orre&t etens$on $n relat$on to the %#n&t$onal 'epth o% the s#l&$
Figure 16.: /
)he use o# stops
Stops sho#l' *e a''e' to sele&te' areas o% the $nternal s#r%a&e o% the tra. *e%ore an. atte)pt $s )a'e at the &ha$rs$'e to a'#st the tra. *or'ers The )ost &onven$ent an' pre&$se )etho' %or a&h$ev$n3 th$s $s %or the stops to *e %or)e' $ n the la*orator. *. tt$n3 2-$n'o-s2 o&&l#sall. thro#3h the -a over -h$&h the a&r.l$& tra. )ater$al $s )o#l'e' Th$s res#lts $n etens$ons %ro) the tra. -h$&h &onta&t the o&&l#sal s#r%a&es o% the teeth or the )#&osa at the sele&te' po$nts
Figure 16.6 /
)he use o# stops
Alternat$ vel. , stops &an *e %or)e' at the &ha$rs$'e *. appl.$n3 a *or'er )o#l'$n3 )ater$al , s#&h as 3reen st$&k tra&$n3 &o)po#n' , to the &hosen lo&at$ons on the tra. The &o)po#n' $s %la)e' an' te)pere' $n -ar) -ater an' then the tra. lo&ate' $n the )o#th #n'er 3entle press#re , th#s )o#l'$n3 the stops to a th$&kness o% appro$)atel. >))
#$
=or>ing impressions
? Figure 16. 'a and b /
,orrecting tra e*tension
or opt$)#) e%%e&t$veness the stops )#st *e &are%#ll. pos$t$one' to ens#re three/po$nt lo&at$on o% the tra. S#$ta*le lo&at$ons %or stops $n&l#'e those areas relate' to the $n&$sal or o&&l#sal s#r%a&es o% the teeth, the palatal va#lt an' poster$or *or'er, an' the retro)olar pa's The. sho#l' not *e pla&e' over teeth that are to *e &overe' *. 'ent#re &o)ponents as the shape o% these teeth sho#l' *e re&or'e' *. an opt$)#) th$&kness o% $)press$on )ater$al An. stops that $n&l#'e )ore than the $n&$sal e'3es or sp t$ps sho#l' *e re'#&e' as the e&ess )ater$al )a. h$n'er reseat$n3 o% the tra.
Figure 16." -
,orrecting tra e*tension
!n&e the stops have *een pre ' , the tra. $s re/$nserte' $nto the )o#th Gentle retra&t$on o% the l$ps an' &heeks -$ll $n'$&ate la*$al or *#&&al over / or #n'er/etens$on An. areas o% over/etens$on sho#l' *e re'#&e', as here -here spa&e has *een &reate' %or the *#&&al %raen#) An. areas o% #n'eretens$on sho#l' *e )a'e 3oo' *. the a''$t$on o% a *or'er/)o#l'$n3 )ater$al s#&h as tra&$n3 &o)po#n' or '$stal etens$on sa''les the tra. sho#l' &over the retro)olar pa's or en&lose the t#*eros$t$es
Figure 16.( -
,orrecting tra e*tension
Asses s)ent o% the l$n3#al etens $on o% the lo-er tr a. $s '$%%$lt *e&a#se o% the )o*$l$t. o% the s#ls t$ss#es an' poor v$s$*$l$t. Anter$orl., th e ete ns$on &an *e &he &ke' -$th the a$' o% a )o#t h )$rr or -h$le the ton3#e $s ra$se', an' poster$orl. *. the '$a3nost$& a''$t$on o% tra&$n3 &o)po#n' to the tra. pr$or to *or'er )o#l'$n3
Figure 16.1$ /
,orrecting tra e*tension
L$n3#al *or'er )o#l'$n3 $s &arr$e' o#t *. ask$n3 the pat$ent to ra$se the ton3#e to &onta&t the #pper l$p , an' then to to#&h ea&h &orner o% the )o#th $n t#rn I% the a''e' )ater$al $s totall. '$spla&e' %ro) the e'3e o% the tra. *. ton3#e )ove)ents +5, the over/eten'e' *or'er )#st *e re'#&e' $% the &o)po#n' has *een )o#l'e' to %or) an etens$on o% the lo-er *or'er +< $t $s &h$lle' an' le%t $n pla&e
A clinical guide to removable partial dentures $oice of impression material -lginate of a lo vis.osity is suitable providing that there are no under.uts so great that the material is stressed beyond its elasti. limit hen the impression is ithdran from the mouth9
F i g u r e 1 6 . 1 1 / The appropriate adhesive for the .hosen material must be applied to the tray in a uniformly thin layer9 It is most important
, that the adhesive film be alloed to dry before the impression h material is brought into .onta.t ith it9 o i c Preparation of t$e mout$ e Figure 16.12 / Preparation o# the outh The la.er o% sal$va that -o#l' other-$se h$n'er the %lo- o% $)press$on
o )ater$al $nto '$re&t &onta&t -$th the teeth sho#l' *e re)ov e' #s$n3 a # -ar) a$r s.r$n3e Th$s $s part$larl. $n'$&ate' -hen there are
'epress$ons $n the tooth s#r%a&e, s#&h as rest seat preparat$ons , an' i -here s$l$&one $)press$on )ater$als are to *e #se' Ho-ever, e&ess$ve 'r.$n3 sho#l' *e avo$'e', other-$se the $)press$on )ater$al )a. a'here to the t$ss#es
p r e s s i o n
Figure 16.13 / Preparation o# the outh !pen $nter'ental spa&es sho#l' *e o&&l#'e' -$th so%t -a pr$or to a$nsert$n3 the loa'e' $)press$on tra., other-$se the $)press$on )ater$al t -$ll %lo- *eneath the &onta&t po$nts an' lo&k the $)press$on $n pla&e eRe)oval o% the $)press$on -o#l' th#s res#lt $n '$stort$on The -a sho#l' o*v$o#sl. not *e per)$tte' to stra. on to a tooth s#r%a&e that $s r i to *e &onta&te' *. an. 'ent#re &o)ponent a l Here, *$lateral l$n3#all. t$lte' pre)olars &reate severe #n'erts an' $t $s there%ore a'v$sa*le to &hoose an elasto)er$& $)press$on )ater$al , s#&h as a s$l$&one r#**er, that possesses s#per$or elast$& propert$es &o)pare' -$th al3$nate
ompleting t$e impression =or ma*imum a..ura.y) the impression material must be thor oughly mi*ed) the tray loaded) inserted and seated in the mouth and border moulding .ompleted before the or5ing time of the material has elapsed9 I t is diffi.ult to determine .lini.ally hen
94
the or5ing time of an elastomer has been rea.hed) sin.e the vis .osity of these materials begins to in.rease immediately after mi* ing has .ommen.ed 9 Thus the or5ing time as stated by the manufa.turer of the material must be observed9
=or>ing impressions Figure 16.14 /
,opleting the ipression
It $s help%#l $% al3$nate $)press$on )ater$al $s -$pe' over the teeth an' $nto 'eep s#l&$ -$th a %$n3er $))e'$atel. pr$or to $nsert$n3 the loa'e' tra. A$r $s there*. '$spla&e' %ro) these areas ens#r$n3 an $)press$on %ree %ro) a$r*lo-s
The tray should not be loaded ith e*.essive quantit ies of material) sin.e there should be only 3mm beteen an a..urately ad6usted tray and the oral tissues9 @*.ess material may flo and obstru.t the patient
Figure 16.1% /
5eep it in position9 ontinued pressure) ith or ithout inad vertent movement of the tray) may introdu.e stresses into the set ting impression material and may deform the tray and the oral stru.tures that support it9 n.e the manufa.turer
Inspecting the ipression
A 3o o' $)pre ss$on sho#l ' h ave ro#n' e' *or'er s that are &orre&tl. s#pporte' *. the tra. There sho#l' *e a )$n$)#) o% a$r*lo-s 3enerall., an' these sho#l' *e ent$rel. a*sent %ro) areas that are to *e &onta&te' *. an. part o% the )etal %ra)e-ork I'eall., no port$on o% the tra. +e&ept %or the stops sho#l' sho- thro#3h the $)press$on
Figure 16.16 /
,opleting the ipression
Care )#st *e taken to preserve the %#n&t$onal 'epth an' -$'th o% the s#l&$ re&or'e' -$th the $)press$on It $s '$%%$lt to atta&h -a *ea'$n3 to al3$nate an' elasto)er $)press$on )ater$als ho-ever , an $n'el$*le pen&$l &an *e #se' to 'ra- a l$ne on the o#ts$'e o% the $)press$on > )) a-a. %ro) the *or'er
Figure 16.1! /
,opleting the ipression
Tr$))$n3 o% the &ast sho#l' *e stoppe' on&e the pen&$l )ark on the stone $s rea&he' An a'eF#ate area o% 2lan'2 +5 $s th#s &reate' on the &ast
(
#%
A clinical guide to removable partial dentures Figure 16 . 1" /
,oon #aults
!*v$o#s '$%%eren&es *et-een the -$'th o% the s#ls on one s$'e o% the $)press $on, an' that on the other )a. $n'$&ate that the tra. -as not &orre&tl. &entre' $n the )o#th an' -as not seate' on the stops
Figures 16.1( and 16.20 $
,oon #aults
Co))on %a#lts are #n'er/etens$on o% the tra. *or'ers or $n&o)plete seat$n3 o% the tra. on $ts stops Both %a#lts lea' to $na'eF#ate s#pport %or the $)press$on )ater$al The &orre&t 'epth an' -$'th o% the s#l&$ are #nl$kel. to have *een re&or'e' an' the $)press$on )ater$al $s al)ost &erta$n to *e '$storte' -hen po#r$n3 the &ast
Figure 16.21 -
,oon #aults
Part$larl. v#lnera*le $n th$s respe&t $s the l$n3#al po#&h The $)press$on )ater$al $s #nl$kel. to re&or' the %#n&t$onal 'epth an' -$'th o% the s#ls #nless the tra. $s &orre&tl. eten'e' an' seate' The sharp *or'er seen here $n'$&ates $na'eF#ate tra. etens$on
Figure 16.22 /
,oon #aults
I% the *or'er o% the tra. -as over/eten'e' the tr#e %#n&t$onal %or) o% the s#l&$ )a. not have *een re&or'e' S#&h over/etens$on sho#l' *e re'#&e' an' the $)press$on retaken
=or>ing impressions I% the impression needs to be reta5en) all the set impression material must be removed from the tray) the tray modified as required) and another thin layer of adhesive applied and alloed to dry before the ne attempt is made 9 Multiple reta5es may result in a thi.5 layer of adhesive on the tray9 1u.h a layer e*hibits poor adhesive propertiesB it must therefore be removed before a ne thin layer is applied9
n.e a..epted) the impression must be rinsed) immersed in a disinfe.tant) and then .ast as soon as possible9 ln the interim period ) alginate materials should be stored under .onditions of /00A humidity 7see =igure +9/,89 @lastomers should be stored dry in sealable plasti. bags9 -s ith preliminary impressions) pre .autions must be ta5en to prevent pressure deformation of the impression material9
!mpression procedure for t$e sublingual bar Figure 16.23 / sublingual bar
Ipression procedure #or the
5 I% th$s &onne&tor $s not to $nter%ere -$th ton3#e )ove)ents, a ver. &are%#l re&or' )#st *e )a'e o% the %#n&t$onal 'epth a n' -$'th o% the l$n3#al s#ls thro#3ho#t the len3th o % the &onne&tor The tra. $s )a'e so that , altho#3h nor)al spa&$n3 $s )a$nta$ne' aro#n' the teeth , the l$n3#al *or'er $s spa&e' onl. 5 )) %ro) the alveolar )#&osa Th$s &loser a'aptat$on o% the tra. to the )#&osa $n the l$n3#al s#ls avo$'s '$stort$on o% the %#n&t$onal -$'th o% the s#ls *. the tra. Stops )#st * e pla&e' to ens#r e repro'#&$*$l$t. o% the tra. pos$t$on '#r$n3 *or'er )o#l'$n3 an' $)press$on tak$n3 < The per$pher. )a. no- *e re%$ne' *. #s$n3 a *or'er/)o#l'$n3 )ater$al s#&h as tra&$n3 &o)po#n' Th$s )ater$al sho#l' *e o% s#%%$&$entl. lo- v$s&os$t. to avo$' '$stort$on o% the s#ls The )ater$al $s )o#l'e' *. reF#est$n3 the pat$ent to )ov e the t$p o% the ton3#e %ro) one &orner o% the )o#th to the other , %ollo-$n3 the &onto#r o% the #pper l$p I% ne&essar., %#rther so%ten$n3 an' )o#l'$n3 o% the tra&$n3 &o)po#n' $s &arr$e' o#t to per%e&t the tra. etens$on > The $)press$on $s &o)p lete' -$th the a$' o% a lo-/ v$s&os$t. )ater$al I% the v$s&os$t. $s too h$3h , over / etens$on o% the $)press$on $n the l$n3#al s#ls $s l$kel. to res#lt (h$le the )ater$al
$s sett$n3 , the pat$ent $s reF#este' to repeat the ton3#e )ove)ents an' then to keep the ton3#e $n the ra$se' pos$t$on &onta&t$n3 the #pper l$p #nt$l the $)press$on has set A%ter re)ov al , the $)press$on o% the l$n3#al s#ls )#st *e &are%#ll. $nspe&te' The *or'er/)o#l'$n3 )ater$al sho#l' *e &overe' *. onl. a ver. th$n -ash o% $)press$on )ater$al A th$&ker la.er o% $)press$on )ater$al $n'$&ates over /etens$on (hen sat$s%$e' -$th the a&ra&. o % the $)press$on, the & l$n$&$an sho#l' 'e)ar&ate the 'epth an' -$'th o% the l$n3#al s#ls *. )ark$n3 the $)press$on at the appropr$ate level -$th an $n'el$*le pen&$l l$ne J ; The te&hn$&$an )#st take &are -hen po#r$n3 the $)press$on an' tr$))$n3 the &ast to ens#re that the %#n&t$onal 'epth an' -$'th o% the s#ls so &are%#ll. re&or'e' $s preserve' It $s essent$al there%ore that the &ast $s not tr$))e' l$n3#all. *elo- the level o% the pen&$l l$ne -h$&h -$ll have *een trans%erre' %ro) the $)press$on to the &ast J : The te&hn$&$an &an no- -a the s#*l$n3#al *ar '$re&tl. $nto the l$n3#al s#ls on the &ast
Figure 16.24 / Ipression procedure #or the sublingual bar In'el$*le pen&$l l$ne 'ra-n *. the 'ent$st on an $)press$on %or a s#*l$n3#al *a r to $n'$&ate to the te&hn$&$an the l$)$t o% l$n3#al tr$))$n3 o% the &ast
97
A clinical guide to removable partial dentures Figure 16 .2% / bar
Ipression procedure #or the sub7ingua7
Cast pro'#&e' %or a s#*l$n3#a *ar &onne&tor sho-$n3 preservat$on o% the %#n&t$onal -$'th an' 'epth o% t he l$n3#al s#ls
!nstructions to t$e laboratory :eside general information about the patient) dental pra.ti.e) date of the ne*t appointment and .onfirmation of disinfe.tion of any .lini.al items) the folloing information should be pro vided on the laboratory pres.ription sheet9 /9 The material to be used for the master .asts9 < I % a metal frameor5 is required) the design is .learly dran by the dentist on the pres.ription sheet and study .ast9 > I % a sublingual bar is required the limit of t rimming of the .ast to retain the idth and depth of the lingual sul.us should be indi.ated9 ; I % a palatal relief 7see =igure #9+8 is required the area for relief should be dran on the study .ast9 This area is determined by the dentist palpating the palate to lo.ate the relatively in.om pressible mu.osa9 : I % rought .lasps are to be used on the !" the dentist should request atta.hment of these to the frameor5 so that they .an be assessed at the metal try$in stage9
#"
9 I % t he altered .ast te.hnique 7hapter /,8 is going to be under ta5en the te.hni.ian is as5ed to atta.h .lose$fitting a.ryli. resin trays to the distal e*tension saddles of the metal frameor59 @ I % a* o..lusal rims are needed to obtain a definitive re.ording of the 6a relationship) the material to be used for suitably rigid and strong bases should be spe.ified9 ptions in.lude shella.) .old$.uring a.ryli. resin) or the metal frameor5 itself 9 +9 ..asionally the dentist may de.ide to progress from the or5ing impression stage straight through to a trial denture 9 Typi.ally this may o..ur if an a.ryli. denture is to be provided to repla.e missing ma*illary anterior teeth9 This
1
'ecording t$e ;a relations$ip mounted on an arti.ulator9 This ill permit .orre.t positioning of the artifi.ial teeth9
T
he ob6e.tive of this stage of .lini.al treatment is to re.ord
a spe.ifi. 6a relationship) su.h as the inter.uspal posi tion or the retruded position) so that the .asts .an be
Figure 1!.1 /
;eneral ob0ective
The &asts )#st *e )o#nte' on the art$lator $n ea&tl. the sa)e o&&l#'$n3 relat$onsh$p as o&rs $n the pat$ent The &o)ple$t. o% the task $s relate' to the n#)*er an' o&&l#sal relat$onsh$p o% the re)a$n$n3 teeth an' )a. *e &ate3or$se' as %ollo-s
Figure 1!.2 /
Stable intercuspal position
S#%%$&$ent teeth )a. *e present to ena*le the &asts to *e pla&e' to3ether a&ratel. $n a sta*le $nterspal pos$t$on at the 'es$re' vert$&al an' hor$ontal a- relat$onsh$p Th#s no a''$t$onal v$s$t *. the pat$ent $s reF#$re' to re&or' the a- relat$onsh$p The #se o% an. $ntero&&l#sal re&or', s#&h as a -a -a%er, $n th$s s$t#at$on $n&reases the &han&e o% $ntro'#&$n3 $na&ra&$es
Figure 1!.3 /
+cclusal stop
!%ten the 'es$re' a- relat$onsh$p &annot *e so eas$l. repro'#&e' o#ts$'e the )o#th even $n the presen&e o% an o&&l#sal stop, *e&a#se there )a. *e $ns#%%$&$ent o&&l#'$n3 teeth to pro'#&e a sta*le pos$t$on o% the &asts
99
A clinical guide to removable partial dentures Figure 1! .4 /
?nacceptable intercuspal position
Alternat$v el. , the o&&l#sal stop )a. pro'#&e an $nterspal pos$t$on at an #na&&epta*le hor$ontal an' vert$&al a- relat$onsh$p T$lt$n3 or 'r$%t$n3 o% teeth, or loss o% tooth s#*stan&e *. a*ras$on, attr$t$on or eros$on , )a. *e &ontr$*#tor. %a&tors res#lt$n3 $n )an'$*#lar 'ev$at$on or re'#&e' o&&l#sal vert$&al '$)ens$on
Figure 1!.# $ Absence o# occ7usal contact !n o&&as$on the re)a$n$n3 tee th )a. *e so pla&e' $n the a-s that the. 'o not prov$'e an o&&l#sal stop , let alone a sta*le &ast relat$onsh$p or these last three s$t#at$ons, o&&l#sal r$)s are a'#ste' $n the )o#th to re&or' the 'es$re' a- relat$onsh$p so that $t &an *e trans%erre' to the &asts
Figure 1! . 6 /
+cc7usal ris
The -a o&&l#sal r$)s )a. *e pla&e' on te)porar. *ases o% shella& or a&r.l$& res$n, or on the 'e%$n$t$ve &ast )etal %ra)e-orks These )#st *e tr$e' $n the )o#th an' the$r sta*$l$t. &he&ke' I% the sta*$l$t. $s poor, .et the *aseplate %$ts the &ast a&ratel. , &ons$'erat$on )#st *e 3$ven to the poss$*$l$t. that the pro*le) $s '#e to an $na&rate $)press$on I% th$s $s &on%$r)e' the -ork$n3 $)press$on )#st *e retaken The retent$on o% the o&&l#sal r$) )#st *e s#%%$&$ent to )a$nta$n the r$) $n pos$t$on '#r$n3 s#*seF#ent re&or'$n3 pro&e'#res
Ad;ustment of t$e rims a* o..lusal rims shou ld only be pla.ed in the mou th long enough to .arry out a parti.ular .lini.al pro.edure9 They must then be removed immediately and .hilled in a bol of .old ater to prevent distortion9
I % an anterior saddle repla.es only one or to teeth) there ill be suffi.ient guidan.e from the remaining teeth to determine the position of the artifi.ial repla.ements9
Figure 1! . ' - Ad0ustent o# the ris (hen )a$llar. anter$or teeth are present , the )$'/$n&$sal po$nt -$ll 3enerall. *e lo&ate' a*o#t 5 &) $n %ront o% the &entre o% the $n&$s$ve pap$lla I% the anter$or teeth are )$ss $n3, th$s relat$onsh$p $s a #se%#l 3#$'e -hen tr$))$n3 the la*$al s#r%a&e o% a r$) $n or'er to restore the appearan&e an' prov$'e the appropr$ate a)o#nt o% l$p s#pport
10 0
'ecording t$e ;a* relations$ip Figure 1!." / Ad0ustent o# the ris The anter$or $n%er$or *or'er o% the r$) sho#l' *e a'#ste' to $n'$&ate the 'es$re' $n&$sal level Th$s $s 'e&$'e' *. re%eren&e to an. a'a&ent teeth an' to the rest$n3 level o% the #pper l$p A l$ne )a. also *e s&r$*e' on the la*$al %a&e o% the r$) to $n'$&ate the proe&te' )$'l$ne o% the $n&$sors (here )an. anter$or teeth are )$ss$n3 the r$) sho#l' *e &arve' #nt$l $ts $n&$sal level $s parallel to the $)a3$nar. hor$ontal l$ne o$ n$n3 the p#p $ls o% t he e.e s +$nt erp# p$lla r. l$n e
Figure 1!.( -
Ad0ustent o# the ris
(hen nat#ral )an'$*#lar anter$or teeth oppose an e'ent#lo#s area $n the anter$or )a$llar. re3$on , the )a$llar. r$) )a. nee' to *e th$nne' %ro) the palatal aspe&t to a&&o))o'ate these teeth $n or'er to a&h$eve the &orre&t a- relat$onsh$p The $n%er$or *or'er an' la*$al %a&e o% the )a$llar. anter$or -a r$) sho#l' *e preserve' to $n'$&ate the 'es$re' pos$t$on o% the art$%$&$al teeth The )a$llar. -a r$)s $n an. poster$or e'ent#lo#s areas are tr$))e' #nt$l the. $n'$&ate the 'es$re' pos$t$on o% the o&&l#sal plane
Figure 1!.1$ / Ad0ustent o# the ris S#%%$&$ent poster$or teeth )a. *e present to $n'$&ate the appro$)ate level o% the o&&l#sal plane
Figure 1! . 11 / Ad0ustent o# the ris (here oppos$n3 nat#ral teeth are present these -$ll nor)all. *e the 'eter)$n$n3 %a&tor $n %$nal$s$n3 the pos$t$on o% the o&&l#sal s#r%a&e o% the r$) Here the r$) has *een )o'$%$e' to a&&o))o'ate a )an'$*#lar tooth that has er#pte' *e.on' the proe&te' o&&l#sal plane
10 1
A clinical guide to removable partial dentures Figure 1! . 12 -
Ad0ustent o# the r i s
I% )an. poster$or teeth are )$ss$n3, the )a $llar. r$) sho#l' *e &arve' #nt$l $t $s parallel to the l $ne o$n$n3 the $n%er$or *o r 'er o% the ala o% the nose to the )$'po$nt o% the tra3#s o% the ear -$th the a$' , $% 'es$re' , o% an o&&l#sal plane 3#$'e
Figure 1!.13 / Ad0ustent o# the ris The -$'th o% the r$) sho#l' also *e a'#ste' #nt$l $t $n'$&ates the 'es$re' *#&&o/l$n3#al pos$t$on$n3 o% the teeth The r$) +5 $s too *#lk., -h$lst r$) +< has *een &orre&te' In the a*sen&e o% a poste r $or a*#t)ent tooth to a&t as a 3#$'e , the *#&&al s$'e o% the )a$llar. r$) sho#l' #st &onta&t the &heek )#&osa -hen the )o#th $s hal% open
Figure 1!.14 - Ad0ustent o# the ris The )an'$*#lar o&&l#sal r$) $s $nserte' an' a'#ste' #nt$l $t )eets the )a$llar. r$) or teeth evenl. #n'er )$n$)al press#re $n the 'es$re' a- relat $onsh$p The r$) sho#l' not then t$lt a-a. %ro) the 'ent#re/ *ear$n3 )#&osa +5 or &o)press the )#&osa or the -a o% the r $) +< T$lt$n3 or &o)press$on -$ll res#lt $n the &ast s not *e$n3 art$late' $n the sa)e relat$onsh$p as the pat$ent2s a-s
Figure 1! . 1% -
Ad0ustent o# the ris
The )an'$*#lar r$) $s also a'#ste' #nt$l $t $n'$&ates the pos$t$on o% the teeth $n the ne#tral one Th$s r$) $s en&roa&h$n3 on the ton3#e spa&e an' nee's to *e re'#&e' on $ts l$n3#al aspe&t
10 -
'ecording t$e ;a* relations$ip Figure 1!.16 / Ad0ustent o# the ris The a- relat$onsh$p )a. *e $n'$&ate' *. $nterspat$on o% so)e o% the re)a$n$n3 teeth (here the e$st$n3 a- relat$onsh$p $s not a&&epta*le or there $s no pos$t$ve o&&l#sal stop , the rest$n3 vert$&al '$)ens$on +5 sho#l' *e assesse' The o&&l#sal vert$&al '$)ens$on o% the r$)s +< )#st then *e a'#ste' so that an a'eF#ate %ree-a. spa&e +> $s prov$'e' (hen 3#$'an&e %ro) poster$or teeth has *een lost, the arelat$onsh$p $n the hor$ontal plane sho#l' *e re&or'e' -$th the )an'$*le $n the retr#'e' pos$t$on as th$s $s repro'#&$*le an' &lose to an a&&epta*le $nterspal pos$t$on
?inalising t$e registration *it$ an acceptable occlusal stop Figure 1! . 1! / Finalising the registration /ith an acceptable occlusal stop A %#rth er )$ll$)etre o% -a $s re) ove' %ro) the o &&l#s al s#r%a &e o% the r$)s to prov$'e a sl$3ht 3ap *et-een oppos$n3 r$)s or teeth, th#s avo$'$n3 the poss$*$l$t. o% o&&l#sal press#re '$stort$n3 e$ther -a or )#&osa To per)$t s#*seF#ent separat$on o% t he o&&l#sal r$)s , one o% the r$)s +#s#all. the )a$llar. an' $ts asso&$ate' teeth are l$3htl. &oate' -$th petrole#) ell.
Figure 1! . 1" /
Finalising the registration
The spa&e *et-een the r$)s $s then taken #p *. a re&or'$n3 )e'$#) that sho#l' *e o% #n$%or)l. lo- $n$t$al v$s&os$t. to avo$' &o)press$on o% the -a or )#&osa , an' that sets r$3$'l. to prov$'e a pos$t$ve an' rel$a*le re3$strat$on I)press$on plaster or a )o'$%$e' $n& o$'ee#3enol paste %#l%$ls these &on'$t$ons so%tene' -a 'oes not
?inalising t$e registration *it$out an acceptable occlusal stop n.e the .orre.t o..lusal verti.al dimension has been a.hieved) no more a* is removed from the rims 9 I% this ere done the o..lusal verti.al dimension ould be de.reasedB otherise the registration pro.edure is as above9
The patient must .lose into the retruded 6a relationship and maintain that position hile the re.ording medium sets under minimal pressure 9
10 3
A clinical guide to removable partial dentures $ec>ing t$e registration Figure 1!.1( /
,hec@ing the registration
An. re&or '$n3 )e'$# ) that has %lo-e' *e.on' the t $ps o% the oppos$n3 sps or e'3e o% the oppos$n3 r$)s $s &are%#ll. tr$))e' so that onl. shallo- $n'entat$ons re)a$n Th$s a$'s '$re&t v$s#al assess)ent o% the a&ra&. o% the re&or' $n the )o#th
Figure 1! .2$ -
,hec@ing the registration
The &asts are no- pla&e' $n o&&l#s$on #s$n3 the o&&l#sal r$)s Tr$))$n3 o% the &asts )a. *e ne&e ssar. to per)$t the$r a&rate lo&at$on $n the re3$strat$on The heels o% the &asts )a. to#&h ea& h other, as sho-n here , or port$ons o% the oppos$n3 r$) or *aseplate an' th#s prevent the &asts %ro) seat$n3 %#ll. $n the o&&l#sal re&or'
Figure 1!.21a and b -
,hec@ing the registration
It $s $)portant to re)e)*er that $t $s the &l$n$&$an2s respons$*$l$t. to ens#re that the 'es$re' a- relat$onsh$p has *een trans%erre' a&ratel. %ro) the )o#th to the &asts The relat$onsh$p o% the nat#ral teeth to ea&h other )#st th#s *e $nspe&te' $% the. are %#rther apart on the &asts +a than the. are $n the )o#th +*V , &o)press$on o% the -a or )#&osa )#st *e s#spe&te'
10
'ecording t$e ;a* relations$ip
Figure 1!.22a and b /
Metal bac@ings
Metal *a&k$n3s are l$kel. to *e reF#$re' %or art$%$&$al )a$llar. anter$or teeth -hen opp os$n3 nat#ral teeth are v$rt#all. &onta&t$n3 the )#&osa o% the e'ent#lo#s area
Figure 1!.23 /
Metal bac@ings
I% th$s $s the &ase the 'ent$st sho#l' ask the la*orator. to pro'#&e a -a tr$al $nsert$on o% the teeth on a shella& or a&r.l$& res$n *aseplate so that the appearan&e o% the 'ent#re &an *e assesse' It $s essent$al %or the pat$ent an' 'ent$st to a3ree on the 'e%$n$t$ve pos$t$on o% the art$%$&$al teeth *e%ore the )etal %ra)e-ork $s &ast As onl. l$)$te' )o'$%$&at$on o% the pos$t$on o% the anter$or teeth $s poss$*le on&e the %ra)e-ork -$th *a&k$n3s has *een pro'#&e' , a ne- %ra)e-ork -o#l' *e reF#$re' $% s#*seF#ent s$3n$%$&ant alterat$on o% the teeth prove' to *e ne&essar.
!nstructions to t$e laboratory are must be ta5en hen sending the .ompleted 6a registration to the laboratory as a* readily distorts if it be.omes arm or is pla.ed under pressure 9 :eside general information about the patient) dental pra.ti.e) date of ne*t appointment and .onfirmation that the .lini.al items have been disinfe.ted) the folloing requests and informa tion should be in.luded on the laboratory pres.ription sheet9 /9 The unanted under.uts that need to be blo.5ed out on the .ast9 These under.uts ill have been noted hen the denture as designed o n an arti.ulated surveyed study .ast9 29 The definitive design for any metal frameor5 in the form of an annotated diagram) supplemented herever possible by an outline dran on the study .ast9 > I % the altered .ast te.hnique 7.hapter /,8 is to be employed at the ne*t appointment) the or5 authorisation should request the addition of a.ryli. resin tray material to the frameor5 to .over the distal e*tension edentulous areas 9 49 The in.lusion of palatal relief hen indi.ated9
I % artifi.ial teeth are to be set up for trial inserti on at the ne*t appointmen t) the folloing additional info rmation is required 9 #9 The shade) mould and material to be used for the artifi.ial teeth9 %9 The desired arrangement 7rotation) in.lination) spa.ing) et.98 of any anterior teeth9 An impression of the e*isting !" may be indi.ated to give a..urate information on this aspe.t if the patient is happy ith the appearan.e9 '9 The material to be used for the base to hold the artifi.ial teeth9 I % the base is not to be the metal frameor5 it must be shella. or a.ryli. resin9 a* bases distort readily at mouth tempera ture9 +9 The type of arti.ulator to be used 9 hen a semi$ad6ustable arti.ulator is required) the laboratory should be supplied ith the ne.essary fa.ebo and o..lusal re.ords 7.hapter ,89 I % the type of arti.ulato r needs to be .hanged at any subse quent stage appropriate instru.tion s ill need to be given at that time9
10/
12
#rial insertion of t$e metal frame*or>
t is re.ommended that the trial insertion of the metal frame
I
pla.e at on.e) the presen.e of a* hinders the sear.h for inter feren.es and additionally) if the .asting needs ad6ustment ith or5 should initially be underta5en ithout the addition of
stones) the heat generated may melt the a*9 I % desired) the frameor5 in a distal e*tension edentulous area may have a .lose$fitting temporary a.ryli. resin base atta.hed to it to permit the re.ording of an altered .ast impression 7.hap ter /,89
Figure / )rial o# the etal any a* rims or1".1 artifi.ial teeth9insertion does not #rae/or@ fit into I% the .asting The %ra)e-ork $s %$rst ea)$ne' on the &ast to ens#re that the pres&r$*e' 'es$3n has *een %ollo-e' An. -ro#3ht &lasps sho#l' have *een $n&l#'e' an' atta&he' to the &ast/)etal %ra)e-ork *. sol'er or &ol'/r$n3 a&r.l$& res$n All &o)ponents sho#l' *e &he&ke' to ens#re that the %$t $s a&rate, that the. are o% a'eF#ate '$)ens$ons an' are &orre&tl. pos$t$one'
Figures 1".2 and 1".3 /
)rial insertion o# the etal #rae/or@
These &o)ponents are not &orre&tl. pos$t$one', *e$n3 too &lose to the 3$n3$val )ar3$ns or %a$l$n3 to &ross the )ar3$ns at an an3le o% at least 70
10
A clinical guide to removable partial dentures Figure 1".4 /
)rial insertion o# the etal #rae/or@
Th$s &o)ponent $s not &orre&tl. pos$t$one' , *e$n3 too &lose to the 3$n3$val )ar3$ns
Figures 1".#) 1" . 6 and 1". ' $ etal #rae/or@
)rial insertion o# the
These &o)ponents are &orre&tl. pos$t$one'
Figure 1"." /
)rial insertion o# the etal #rae/or@
The sta*$l$t. o% the &ast$n3 sho#l' *e &he&ke' #n'er %$n3er press#re 1enne'. Class I an' II %ra)e-orks 9A ,linical ;uide )o eovable Partial 'enture 'esign &hapter < -$th a spa&e' )esh -$ll ro&k $% press#re $s appl$e' to the sa''le area #nless a stop or %oot +arro-e' $s prov$'e' to s#pport the )esh #ll. tooth/s#pporte' %ra)e-orks sho#l' not ro&k
102
#rial insertion of t$e metal frame*or> Figure 1" .( /
)rial insertion o# the etal #rae/or@
The %$tt$n3 s#r%a&e o% )aor &onne&tors &over$n3 the 3$n3$val )ar3$n sho#l' *e $nspe&te' An. sharp )etal enter$n3 the 3$n3$val &rev$&e sho#l' *e re)ove' Th$s )#st *e 'on e -$th &are ho-ever, as e&ess$ve ston$n3 -$ll &reate a spa&e *eneath the &onne&tor $nto -h$&h the 3$n3$vae -$ll prol$%erate
The frameor5 is no tried in the mouth) utilising the .omplete seating9 -ny areas of abrasion on the .ast may indi.ate intended path of insertion9 I % the frameor5 does not seat fully) the lo.ation of ina..ura.ies in the frameor59 lini.al e*amina no attempt should be made to for.e it into pla.e) as subsequent tion ith a mouth mirror may reveal interfering .onta.ts removal from the mouth may be e*tremely diffi.ult9 - system beteen frameor5 and teeth 9 entle ro.5ing of the frameor5 ati. sear.h must be underta5en to dis.over hat is preventing may reveal a dis.repan.y of %$t a.ting as a ful.rum9
Figure 1".1$ /
)rial insertion o# the etal #rae/or@
More pre&$se lo&at$on o% an. $nter%eren&e )a. *e a&h$eve' *. the #se o% '$s&los$n3 a$'s s#&h as th$s so%t -a -h$&h $s )elte' an' %lo-e' on to the s#spe&t area o% the %ra)e-ork The %ra)e-ork $s then seate' as %ar as $t -$ll 3o, -$th'ra-n an' $nspe&te' to see $% $n$t$al &onta&ts *et-een the %ra)e-ork an' teeth are v$s$*le as areas -here the '$s&los$n3 -a has *een '$spla&e' , epos$n3 the )etal These &onta&ts &an then *e el$)$nate'
Figure 1".11 /
)rial insertion o# the etal #rae/or@
Care )#st *e taken to avo$' a'#st$n3 those port$ons o% &onne&tors that are o&&l#sal to the s#rve. l$nes I% )ater$al $s re)ove' %ro) these areas a spa&e -$ll *e &reate' *et-een 'ent#re an' tooth s#r%a&e $nto -h$&h %oo' &an pa&k An.th$n3 other than relat$vel. )$nor a'#st)ents to the %ra)e-ork $n'$&ates a 3enerall. poor %$t, an' &ons$'erat$on )#st *e 3$ven to retak$n3 the )aster $)press$on an' o*ta$n$n3 a ne%ra)e-ork
n.e the frameor5 is fully seated in the mouth) its stability is assessed9 - de.ision as to hether an altered .ast impression is required must then be made before obtaining the definitive re.ording of the 6a relationship 9 The %$t and positioning of all the .omponent parts of the
frameor5 are again assessed) in.luding the e*tension of the mandibular ma6or .onne.tor in relation to the fun.tional depth of the sul.us9 I % unsatisfa.tory) a ne impression and .asting are required9
10
A clinical guide to removable partial dentures Figure 1" . 12 /
)rial insertion o# the etal #rae/or@
(hen oppos$n3 nat#ral teeth prov$'e an o&&l#sal stop , &are )#st *e taken to &he&k that the %ra)e-ork 'oes not alter th$s o&&l#sal relat$onsh$p , e3 *. separat$n3 the teeth The pat$ent2s &o))ents are val#a*le $n 'ete&t$n3 the presen&e an' lo&at$on o% o&&l#sal pre)at#r$t$es S#&h &o))ents )#st *e s#pple)ente' *. v$s#al assess)ent , the #se o% art$lat$n3 paper to )ark o&&l#sal &onta&ts , an' test$n3 the a*$l$t. o% an. teeth prov$'$n3 an o&&l#sal stop to 3r$p a str$p o% th$n )etal %o$l +sh$)sto&k Pre)at#re o&&l#sal &onta&ts )#st *e el$)$nate' *. sele&t$ve 3r$n'$n3 #nt$l the 'es$re' a- relat$onsh$p $s esta*l$she'
!nstructions to t$e laboratory :eside the general information about patient) dental pra.ti.e) date of the ne*t appointment and .onfirmation of disinfe.tion of .lini.al items) the folloing information should be provided on the laboratory pres.ription sheet9 /9 I % the altered .ast te.hnique is to be employed at the ne*t appointment) the or5 authorisation should request the addi tion of a.ryli. resin tray material to the frameor5 to .over the distal e*tension edentulous areas9 29 -ny additional laboratory alterations of the frameor5 that are required9
11 0
I% teeth are to be set up on the frameor5 for the trial insertion of the a*ed$up denture the folloing additional information ill be required( 39 The shade) mould and material to be used for the artifi.ial teeth9 49 The desired arrangement 7rotation) in.lination) spa.ing) et.98 of any anterior teeth9
1
Al.tered cast tec$niue
Figure 1(. 1 (hen a '$stal etens$on sa''le $s &onstr#&te' on a &ast po#re' %ro) a )#&ostat$& $)press$on, the '$%%erent$al $n the s#pport o%%ere' *. the a*#t)ent tooth $n $ts relat$vel. $n&o)press$*le per$o'ontal l$3a)ent an' the )ore '$spla&ea*le 'ent#re /*ear$n3 )#&osa $s 3reatest As a res#lt, the ten'en&. %or the '$stal etens$on sa''le to s$nk #n'er o&&l#sal loa' an' p$vot a*o#t the rest on the a*#t)ent tooth $s $n&rease'
Figure 1(.2 The o*e&t$ve o% the altere' &ast te&hn$F#e $s to re'#&e the s#pport '$%%erent$al %or a '$stal etens$on sa''le *. o*ta$n$n3 a &o)press$ve $)press$on o% the e'ent#lo#s area #n'er &on'$t$ons -h$&h )$)$& %#n&t$onal loa'$n3 The '$str$*#t$on o% loa' %ro) the 'ent#re to the res$'#al r$'3e $s th#s $)prove' an' the 'ent#re $s )ore sta*le
Figure 1(.3 A&r.l$& res$n tra. )ater $al $s a'' e' t o the % ra)e-or k to %or ) a *as e that &overs the relevant e'ent#lo#s area It )#st *e o% s#%%$&$ent th$&kness to *e r$3$' At the &ha$rs$'e the per$pher. o% the *ase $s $nspe&te' %or #n'er/ or over/etens$on an' a'#ste' a&&or'$n3l. An. #n'erts $n the $)press$on s#r%a&e are re)ove' Th$s s#r%a&e $s 'r$e' an' $n& o$'e $)press$on paste or )e'$#)/v$s&os$t. s$l$&one $)press$on )ater$al appl$e'
// /
A clinical guide to removable partial dentures Figure 1(.4 The %ra)e-ork $s pla&e' $n the )o#th an' 3reat &are )#st *e taken to ens#re that $t $s seate' on the teeth *. press#re on the o&&l#sal rests an' $n'$re&t reta$ners onl. There )#st *e no %$n3er press#re appl$e' to the *ase area, nor )#st the oppos$n3 teeth *e allo-e' to o&&l#'e on an. part o% the %ra)e-ork !n&e the %ra)e-ork $s %#ll. seate' , *or'er )o#l'$n3 $s &arr$e' o#t
Figure 1(.% (hen the $)press$on )ater$al has set, the %ra)e-ork $s re)ove' %ro) the )o#th an' the $)press$on $nspe&te' An. errors )#st *e &orre&te' *. appropr$ate )o'$%$&at$on or *. retak$n3 the $)press$on
In the original approa.h to the altered .ast te.hnique the impression is developed using a spe.ially formulated a* that flos readily at mout h temperatur e 9 This te.hnique has th e advantage of alloing progressive modifi.ation of the impres sion until an ideal result is a.hieved9 ;oever) it requires
signifi.antly more .hairside time than the te.hnique des.ribed and employs a .ommer .ial a* 7Lerr
Figure 1(.6 !n&e a sat$s%a&tor. $)press$on has *een o*ta$ne' the nee' %or an etra &l$n$&al sta3e to re&or' the a- relat$onsh$p &an *e avo$'e' *. a''$n3 -a r$)s to the %ra)e-ork at the &ha$rs$'e an' pro&ee'$n3 -$th the re&or'$n3 at the sa)e appo$nt)ent
11-
Altered cast tec$niue Figure 1(.! (hen the &o)plete' $)press$on has *een &onve.e' to the la*orator., the relevant e'ent#lo#s areas are t %ro) the or$3$nal )aster &ast The %ra)e-ork $s &are%#ll. an' a&ratel. seate' on the teeth
Figure 1(." $nall., a ne- &o)pos$te &ast $s pro'#&e' *. po#r$n3 art$%$&$al stone $nto the sa''le $)press$on (hen the a&r.l$& tra. $s re)ove' %ro) the %ra)e-ork $t -$ll #s#all. *e seen that the )etal 2%oot2 atta&he' to the spa&e' )esh +$3#re 588 has lost &onta&t -$th the #n'erl.$n3 r$'3e I% th$s $s the &ase a s)all port$on o% &ol' /r$n3 a&r.l$& res$n sho#l' *e a''e' to the )es h at th$s po$nt to re /esta*l$sh the &onta&t an' to s#pport the %ra)e-ork on the &ast
ebasing the .ompleted !" is an alternative approa.h to the altered .ast impression for redu.ing the support differen tial beteen mu.osa and abutment tooth9 - suitable impres sion material) su.h as >in. o*ideKeugenol impression paste) is applied to the a.ryli. fitting surfa.e of the relevant saddles after
removing any under.uts) and an impression ta5en ith the den ture being seated by pressure on the o..lusal rests and indire.t retainers only9 !ressure is not applied to the o..lusal surfa.es of the artifi.ial teeth9 The resulting impression is used to rebase the saddle9
Figure 1(.( A '$sa'vanta3e o% th$s )etho' $s that $t -$ll #s#all. '$sr#pt the evenness o% o&&l#sal &onta&t $n the sa''le area *. &reat$n3 pre)at#re &onta&ts poster$orl. The o&&l#sal &orre&t$on reF#$re' &an *e F#$te &ons$'era*le
!nstructions to t$e laboratory :eside general information about the patient) the dental pra.ti.e and .onfirmation that the .lini.al items have been disinfe.ted) the folloing information and requests should be entered on the laboratory pres.ription sheet9 /9 The distal e*tension edentulous areas should be trimmed from the .ast) the frameor5 a..urately seated and ne model material poured into the altered .ast impressions9 < I % the metal
39 The .asts should be re$arti.ulated on the .hosen arti.ulator using the definitive re.ording of the 6a relationship if this as obtained after the altered .ast impression as ta5en9 th erise the addition of a* rims to the frameor5 should be requested so that the re.ording .an be made at the ne*t visit9 I % teeth are to be added to the frameor5 for the ne*t appoint ment the folloing additional information ill be required9 49 The shade) mould and material to be used for the artifi.ial teeth9 #9 The desired arrangement 7rotation) in.lination) spa.ing) et.98 of any anterior teeth9 113
-0
#rial insertion of *a5ed6up dentures
his is the last stage at hi.h modifi.ations .an be made before the a* is repla.ed by a.ryli. resin9 - .areful ro u
T
=a5 try6in for metal dentures @a.h denture should first be e*amined on the arti.ulated .asts9
tine mu st be folloed to prevent any errors from .on tinuing through to the finished dentures9
Figure 2$. 1 /
a* tr-in #or etal dentures
The pos$t$on$n3 o% an. poster$or teeth $s &o)pare' -$th the pos$t$on o% the re)a$n$n3 nat#ral teeth an' -$th the pres&r$pt$on s#ppl$e' to the la*orator. v$a the o&&l#sal r$) $% th$s $s ava$la*le or ea)ple, teeth on *o#n'e' sa''les +e3 <: an' <9 sho#l' *e $n l$ne -$th the *#&&al s#r%a&es o% the nat#ral teeth Palatall. pla&e' teeth +e3 5: an' 5; -$ll en&roa&h on the spa&e %or t he ton3#e Tooth pos$t$ons -$ll nee' to *e &on%$r)e' on $ntra/oral ea)$nat$on
Figure 2$.2a and b -
a* tr-in #or etal dentures
The arran3e)ent o% the anter$or teeth sho#l' *e pleas$n3 to the e.e an' &on%or) to an. reF#ests on the la*orator. &ar' The la*$al s#r%a&es an' $n&$sal e'3es sho#l' har)on$se -$th the a*#t)ent teeth I% $n&$sal -ear $s present on the nat#ral teeth $t sho#l' *e s$)#late' on the 'ent#re The appearan&e o% the $n&$sors $n +a $s less a&&epta*le than that $n +* The appearan&e )a. nee' to *e )o'$%$e' a%ter *oth the pat$ent an' the 'ent$st hav e ha' the opport#n$t. to v$e- the 'ent#re $n the )o#th
s
11
A clinical guide to removable partial dentures The inter.uspation of the teeth should be even) and in order to redu.e the magnit ude of the potentially damaging lateral for.es) as mu.h balan.ed o..lusion and arti.ulation as possible
should be provided ithin the .onstraints imposed by the remaining natural teeth9 The natural teeth should) herever pos sible) a.t as a guide9
Figure $%.3 -
a* tr-in #or etal dentures
(a %lan3es sho#l' *e o% a th$&kness an' etens$on &orrespon'$n3 to the a)o#nt o% *one resorpt$on $n the area so that the. onl. repla&e the t$ss#e that has *een lost , restor$n3 the %or)er &onto#r o% the alveolar r$'3e Mes$al an' '$stal *or'ers sho#l' *e th$n so that the %lan3e *len's -$th the a'a&ent )#&osa , th#s avo$'$n3 %oo' trapp$n3 an' pro)ot$n3 pat$ent &o)%ort
Figure 2$.4 /
a* tr-in #or etal dentures
I% the path o% $nsert$on an' -$th'ra-al per)$ts , the lateral *or'ers o% an. anter$or %lan3e sho#l' *e th$nne' an' sho#l' ter)$nate over the &onve$t$es pro'#&e' *. the roots o% the a*#t)ent teeth Th$ s arran3e)ent sho#l' alsoper)$t the la*$al %lan3e to restore the pap$lla o% the a*#t)ent tooth net to the e'ent#lo#s spa&e The pos$t$on$n3 an' &onto#r o% pap$llae an' 3$n3$val )ar3$ns aro#n' the art$%$&$al teeth sho#l' har)on$se -$th those o% the a'a&ent nat #ral teeth
Figure <0 :a and b /
a* tr-in #or etal dentures
A & o))o n error, -h$&h &reates a poo r appea ran&e , $s to pla&e t he 3# ) ) ar3$n o% the art$%$&$al )a$ll ar. pre)olars at a lo-er level than that o% the a'a&ent nat#ral teeth +a Th$s )a. *e over&o)e *. &are%#l -a$n3 #p an' *. the sele&t$on o% an art$%$&$al tooth o% appropr$ate &ro-n len3th +*
11
#rial insertion of *a5ed6up dentures Figure 2$.6 /
a* tr-in #or etal dentures
The *or'ers o% )#&osa, or part$all. )#&osa/s#pporte' sa''les, sho#l' eten' to the %#ll 'epth o% the s#l&$ re&or'e' on the &ast Th$s $s so that the o&&l#sal %or&es )a. *e '$str$*#te' as -$'el. as poss$*le an' so that the a'a&ent )#slat#re )a. *e #t$l$se' to re$n%or&e the retent$on an' sta*$l$t. o% the prosthes$s
Figure 2$ . ' $
a* tr-in #or etal dentures
I% the &hosen path o% $nsert$on an' -$th'ra-al %or the 'ent#re 'oes not el$)$nate #n'erts on the la*$al or *#&&al s$'es o% the r$'3e, the %lan3es sho#l' *e th$nne' as the. pass over the s#rve. l$ne an' en' appro$)atel. 5)) *e.on' $t
The dentures are no seated in the mouth along their planned path of insertion so tha t the fit) posi tioning of all .omponents and flange e*tension .an be .he.5ed by visual inspe.tion9 =un. tional movements of the lips) .hee5s and tongue should not dis pla.e the denture 9 The relationship of the artifi.ial teeth to the soft tissues should be assessed to determine hether the pre s.ription supplied by the o..lusal rims has been folloed9 The
Figure <0 " /
verti.al and hori>ontal 6a relationships are .he.5ed utilising the patient
a* tr-in #or etal dentures
The pat$ent )#st )a$nta$n onl. the l$3htest poss$*le o&&l#sal &onta&t -h$le the o&&l#s$on $s *e$n3 &he&ke', other-$se an. pre)at#re o&&l#sal &onta&t )a. *e )aske' *. '$stort$on o% the 'ent#re *ase , *. '$spla&e)ent o% the )#&osa or, as sho-n here , *. )ove)ent o% the tr$al 'ent#re a-a. %ro) the t$ss#es Corre&t$on o% s$3n$%$&ant o&&l#sal errors -$ll reF#$re the repla&e)ent o% the art$%$&$al teeth -$th -a r$)s so that the arelat$onsh$p &an *e re/re&or'e'
11
A clinical guide to removable partial dentures Figure $% .9 -
a* tr-in #or etal dentures
The sha'e , )o#l' an' arran3e)ent o% the art$%$&$al teeth sho#l' har)on$se -$th the nat#ral teeth The $n&$sal e'3es o% the nat#ral anter$or teeth ten' to %ollo- the rve %or)e' *. the lo-er l$p -hen s)$l$n3 Repro'#&t$on o% th$s relat$onsh$p -hen pos$t$on$n3 art$%$&$al anter$or teeth &an &ontr$*#te s$3n$%$&antl. to a pleas$n3 appearan&e The pat$ent )a. *e a*le to re&all '$st$n3#$sh$n3 %eat#res o% the )$ss$n3 nat#ral teeth or )a. *e $n possess$on o% s#$ta*le photo3raphs Re)e)*er that a totall. re3#lar arran3e)ent o% art$%$&$al teeth al)ost al-a.s looks art$%$&$al
Figure $%. 1% $
a* tr-in #or etal dentures
!n o&&as$on , see)$n3l. *$arre reF#ests %ro) the pat$ent )a. *e a&&epte' , prov$'e' that the. 'o not &o)pro)$se the sta*$l$t. , retent$on an' %#n&t$on o% the 'ent#re I% the reF#est $s not )et , the 'ent#re )a. *e totall. ree&te' *. the pat $ent In'ee', tooth arran3e)ents that appear ea33erate' o#t o% the )o#th are o%ten a&&epta*le in viv o as seen on th$s &o)plete' 'ent#re
Figure $% . 11 $
a* tr-in #or etal dentures
The s)ooth s#r%a&e o% the %lan3e sho-n here sho#l' *e avo$'e' $% the %lan3e $s l$kel. to *e v$s$*le '#r$n3 %#n&t$on as $t pro'#&es an art$%$&$al appearan&e Instea', the %lan3e sho#l' *e st$pple' an' &onto#re' to )$)$& the )#&osal s#r%a&e an' *reak #p re%le&te' l $3ht $n a )or e nat#ral )anner The #nsat$s%a&tor. appearan&e $s also '#e to the '$%%eren&e $n sha'e *et-een 55 an' <5 an' to the sl$3ht '$s&repan&. $n the $n& $sal level
Figure $%. 1$ $
a* tr-in #or etal dentures
An. sta$ns to * e $n&or porate ' $n the teeth or a&r.l$ & res$n %lan3e sho#l' *e $n'$&ate' on a 'ra-$n3 atta&he' to the la*orator. pres&r$pt$on &ar'
112
#rial insertion of *a5ed6up dentures Figure 2$. 13 /
a* tr-in #or etal dentures
These $nstr#&t$ons are part$larl. $)portant -here there $s p$3)entat$on o% the )#&osa a$l#re to t$nt the %lan3e to )at&h the a'a&ent )#&osa -$ll res#lt $n the h$3hl. #nsat$s%a&tor. appearan&e sho-n here
Figure 2$ . 14 /
a* tr-in #or etal dentures
Care%#ll. planne' an' eete' t$nt$n3 o% the la*$al %lan3e &an &reate th$s &onv$n&$n3l. nat#ral res#lt
The appearan.e of the trial denture must alays be dis.ussed ith the patient) using a mirr or 7preferably all$mounted to ensure that vieing ta5es pla.e at .onversation distan.e8 to vie the situation before and after any modifi.ation9 -pproval of the
Figure 2$. 1% /
appearan.e must be obtained before the denture is pro.essed9
=a5 try6in for acrylic dentures @a.h denture should first be e*amined on the arti.ulated .asts 9
a* tr -in #or acrlic dentures
The 'es$3ns sho#l' *e &he&ke' a3a$nst the pres&r$pt$on s#ppl$e' to the la*orator. (ro#3ht rests an' &lasps sho#l' *e o)$tte' at th$s sta3e as the. &annot *e serel. atta&he' to the tr$al 'ent#re The. are there%ore l$a*le to )ove '#r$n3 $nsert$on o% the tr./$n so that the$r &ontr$*#t$on to retent$on an' sta*$l$t. &annot *e assesse'
11
A clinical guide to removable partial dentures Figure 2$ . 16 / a* tr-in #or acrlic dentures In s$t#at$ons -here the 3$n3$val )ar3$n $s to *e le%t #n&overe' , the *or'er o% the tr$al 'ent#re $s ea)$ne' to ens#re that $t $s at least > )) &lear o% the 3$n3$val )ar3$ns, an' that -here $t &rosses the )ar3$ns $t 'oes so at 70 or )ore +a It )a. *e '$%%$lt to a&h$eve th$s a)o#nt o% &learan&e $n relat$on to one stan'$n3 teeth s#&h as 5> an' $t )a. there%ore *e )ore appropr$ate to &over the palatal 3$n3$val )ar3$n +*
Figure 2$. 1! /
a* tr-in #or acrlic dentures
(here the -a &onta&ts nat#ral teeth , $t )#st 'o so at or a*ove the s#rve. l$nes +J I% $t en's *elo- the l$ne, a 3ap *et-een a&r.l$& an' tooth -$ll res#lt -hen the &o)plete' 'ent#re $s $nserte' -h$&h per)$ts 'ent#re )ove)ent an' %oo' pa&k$n3 (here the tooth s#r%a&e $s not #n'ert , rel$e% sho#l' not *e prov$'e' %or the 3$n3$val )ar3$ns The pos$t$on$n3 o% the teeth, the &onto#r $n3 o% the -a %lan3es an' sta*$l$t. o% the 'ent#re on the &ast are &he&ke' as 'es&r$*e' prev$o#sl.
Figure 2$ . 1" /
a* tr-in #or acrlic dentures
It $s $)portant to ens#re that #n-ante' #n'erts have *een *lo&ke' o#t as reF#este' on the la*orator. &ar' I%, as $n the $ll#strat$on , -a has *een #se' %or th$s p#rpose, the &ast )#st *e '#pl$&ate' pr$or to the pro&ess$n3 o% the 'ent#re
The dentures are no seated in the mouth along their plate 9 The flange e*tension is .he.5ed and appropriate .orre. plan ned path s of ins ertion9 =it and stability are .arefully tive measures undert a5en9 assessed9 -lloan.e must be made for the ine*a.t fit of the base$
1- 0
#rial insertion of *a5ed6up dentures Figure 20 9 1( /
a* tr-in #or acrlic dentures
(hen an a&r.l$& &onne&tor $s to *e %#ll. eten'e' poster$orl., $t sho#l' ter)$nate #st anter$or to the v$*rat$n3 l$ne -here )ove)ent o% the so%t palate *e3$ns +here )arke' -$th $n'el$*le pen&$l A 3roove , the post 'a), $s t $nto the &ast $n th$s pos$t$on, eten'$n3 thro#3h ea&h ha)#lar not&h The 'epth an' -$'th o% the 3roove 'epen's on the t$ss#e &o)press$*$l$t. as 'eter)$ne' *. palpat$on The 3roove $s 3enerall. 'eeper an' -$'er laterall. $n the palate than $n the )$'l$ne
Figure 209 2$ /
a* tr-in #or acrlic dentures
The post/'a) has a vert$&al poster$or -all an' $s &ha)%ere' anter$orl. Th$s per)$ts the poster$or *or'er o% the palatal &onne&tor to *e th$nne' an' t#rne' $nto the t$ss#es, a''$n3 to pat$ent &o)%ort an' &reat$n3 a poster$or seal
Figure 2$.21 /
a* tr-in #or acrlic dentures
Narro-er 3rooves , the$r 'epth a3a$n 'eter)$ne' *. &l$n$&al assess)ent o% t$ss#e &o)press$*$l$t., are also t $nto the )#&osal areas o% the &ast alon3 the other propose' *or'ers o% palatal a&r.l$& &onne&tors These 2p$n/'a)s2 pro'#&e &lose a'aptat$on o% the *or'ers , re'#&$n3 the $n3ress o% %oo' The pos$t$on$n3 o% the poster$or teeth, the a- relat$onsh$ps, an' the appearan&e are &he&ke' as 'es&r$*e' prev$o#sl.
!nstructions to t$e laboratory :eside general information about the patient) the dental pra. ti.e) date of the ne*t appointment and .onfirmation that the .lin i.al items have been disinfe.ted) the laboratory pres.ription sheet should in.lude a list of any modifi.ations to be .arried out to the a*ed$up dentures or .asts9 It is advisable to have another trial insertion appointment after anything but the most minor mod ifi.ations) and this is mandatory after re$re.ording the 6a rela tionship9 I % the dentures are to be finished) request the folloing9 /9 "upli.ation of the .ast if the unanted under.uts are .ur9 rently blo.5ed out in a*) or if the finished denture is to bt fitted ba.5 onto a dupli.ate .ast in the laboratory9 This latter step is re.ommended as it helps to ensure trouble$free inser tion of the .ompleted denture at the ne*t appointment9
29 The addition of any rought .lasps or rests omitted from the trial denture9 39 orre.tions of any errors noted in the trial dentures) eg fail ure of any a*or5 .onta.ting the teeth to e*tend to the sur vey lines9 In .ertain situations here the aestheti. requirements require it the folloing may also be in.luded9 49 The shade to be used for the pin5 a.ryli. resin9 #9 -ny spe.ial finish 7eg stippling8 to be applied to the surfa.e of the a.ryli. resin9 %9 - diagram of any stains to be in.orporated into the pin5 resin or teeth 9
1- 1
-1 Figure 21.1 -
!nsertion of t$e completed denture
Insertion o# the copleted denture
The 'ent#re $s ea)$ne' to ens#re that the pol$she' s#r%a&es are -ell %$n$she' The *or'ers sho#l' *e ro#n'e' an' not sharp +5 The $)press$on s#r%a&e sho#l' not have an. an. 2a&r.l$& pearls 2 +<, nor sho#l' there *e an. sharp e'3es +> The latter are &o))onl. %o#n' $n the area o% the palatal r#3ae an' at the *or'ers o% a rel$e% area
Figure 21.2 -
Insertion o# the copleted denture
I% a&r.l$& res$n has entere' the 3$n3$val s#ls a'a&ent to the nat#ral teeth +le%t, the res#ltant sharp r$'3e o% a&r.l$& res$n sho#l' *e el$)$nate' +r$3ht Care )#st *e taken not to re)ove e&ess )ater$al, s$n&e the so%t t$ss#es are l$a*le to prol$%erate $nto the spa&e so &reate'
I% the denture has been returned from the laboratory on dupli .ate .asts) the latter should be e*amined for signs of abrasion produ.ed by for.ing rigid portions of the denture into pla.e9 1u.h abraded areas indi.ate parts of the denture that may require ad6ustment9 The denture is no seated $n the mouth along the planned path
Eof insertion and ithdraal9 I% it does not seat) it is li5ely to be due to a.ryli. resin having entered under.uts related to the nat ural teeth or the alveolar ridges9 The area of a.ryli. resin involved may be dete.ted by visual inspe.tion or by the use of dis.losing media as des.ribed in =igure /+9/09
1-3
A clinical guide to removable partial dentures Figure 21.3 -
Insertion o# the copleted denture
I% the $nter%eren&e -$th $nsert$on $s relate' to a %lan3e, the area respons$*le )a. *e $n'$&ate' *. the appearan&e o% *lan&h$n3 o% the )#&osa as atte)pts are )a'e to pass the a&r.l$& %lan3e over the )ost pro)$nent part o% the alveolar r$'3e
Figure 21.4 -
Insertion o# the copleted denture
The a&r.l$& res$n, -h$&h prevents $nsert$on o% the 'ent#re +&ross hat&he' $s re)ove' , tak$n3 &are to preserve the &onta&t *et-een 'ent#re an' har' an' so%t t$ss#es $n the non/#n'ert areas
n.e the denture is seated and is .omfortable the fit of all its .omponents is .he.5ed9 There is eviden.e that even apparently ell$fitting rests might not a..urately .onta.t the surfa.e of the rest seat9 I % this is thought to be signifi.ant $n a parti.ular .ase) an effe.tive) though perhaps underused)
ing the .omposite ith the frameor5 in situ) removing the frameor5) light$.uring the .omposite again and finishing the .omposite margins if ne.essary9 The denture should be retentive and stable9 I % distal e*tension saddles ro.5 about their most distal o..lusal rests) this should be .orre.ted by relining the saddles9 The o..lusion is assessed from the patient
Figure 21.% -
Insertion o# the copleted denture
Nat#ral teeth )a. *e separate' *. pre)at#re &onta&ts on art$%$&$al teeth The latter )#st *e &are%#ll. a'#ste' #nt$l the nat#ral teeth )eet $n pre&$sel. the sa)e -a. -$th or -$tho#t the 'ent#re $n pla&e (here nat#ral teeth 'o not $n'$&ate the 'es$re' a- relat$onsh$ps, the art$%$&$al teeth )#st *e a'#ste' to prov$'e even o&&l#sal &onta&t at t h opt$)al o&&l#sal vert$&al '$)ens$on $n the retr#'e' arelat$onsh$p #rther a'#st)ent sho#l' *e #n'ertaken to per)$t even &onta&t to *e )a$nta$ne' $n an $nterspal pos$t$on sl$3htl. anter$or to the retr#'e' &onta&t pos$t$on In lateral an' protr#s$ve ers$on the 'ent#re teeth sho#l' nor)all. *e a'#ste' so that the. 'o not '$st#r* the 3#$'an&e o%%ere' *. the re)a$n$n3 nat#ral teeth
-rti.ulating paper may help to lo.alise any premature o..lusal .onta.t7s89 The paper should be applied bilaterally in order to dis.ourage deviation of the mandible on .losure9
1-
The paper is relatively thi.5) and .are must be ta5en to grind only those mar5s that indi.ate a.tual tooth .onta.t9
!nsertion of t$e completed denture Figure 21.6 -
Insertion o# the copleted denture
Heav. tooth &onta&t $s $n'$&ate' *. 2tar3et2 )ark$n3s , hav$n3 a l$3ht &entre s#rro#n'e' *. a r$n3 o% $nk trans%erre' %ro) the paper !ther )arks , s$)pl. pro'#&e' *. the paper tak$n3 #p the spa&e *et-een the teeth, are 3enerall. less '$st$n&t an' la&k the l$3hter &entre D$%%erent$at$on *et-een heav. an' l$3ht tooth &onta&ts &an also *e )a'e -$th sh$)sto&k , -h$&h -$ll eas$l. p#ll o#t %ro) *et-een teeth not $n %$r) &onta&t
Figure 21. ' $
'
Insertion o# the copleted denture
In those &ases -here the RP! sa''les are etens$ve an' the 3#$'an&e $n e r s$on %ro) the re)a$n$n3 nat#ral teeth allo-s the )a$ntenan&e o% *$lateral *alan&$n3 &onta&ts , the %ollo-$n3 )etho' o% o&&l#sal a'#st)ent sho#l' *e a'opte' The )a$llar. palatal sps an' )an'$*#lar *#&&al sps &onta&t$n3 the %ossae o% the oppos$n3 teeth )a$nta$n the o&&l#sal vert$&al '$)ens$on These sps are there%ore kno-n as supporting sps
Figure 21." /
Insertion o# the copleted denture
I% one o% these sps &onta&ts pre)at#rel. +J -hen the pat$ent atte)pts to rea&h $nterspal pos$t$on an' $s also pre)at#re $n lateral ers$ons , the sp $s re'#&e' $n he$3ht
Figure 21.( /
Insertion o# the copleted denture
I% the sp &onta&ts pre)at#rel. on &los#re as *e%ore +J , *#t $s not pre)at#re $n lateral ers$ons, the %ossa $s 'eepene' !n&e even o&&l#sal &onta&t $s a&h$eve' at the 'es$re' stat$& a - re lat $on sh$ p , %#rther a'#st)ent o% the s#pport$n3 sps sho#l' *e avo$'e' $% poss$*le
1- /
A clinical guide to removable partial dentures Figure 21. 1$ -
Insertion o# the copleted denture
Th#s $% a pre)at#re &onta&t o&rs *et-een a *#&&al )a$llar. sp an' a )an'$*#lar *#&&al sp on the -ork$n3 s$'e $n lateral ers$on , onl. the *#&&al #pper +BU sp $s a'#ste'
Figure 21.11 -
Insertion o# the copleted denture
S$)$larl., $% $n the sa)e ers$on , &onta&t o&rs *et-een the )a$llar. palatal an' l$n3#al )an'$*#lar sps , the l$n3#al lo-er +LL sp $s re'#&e' Th$s )etho' o% a'#st$n3 tooth &onta&t on the -ork$n3 s$'e $s th#s &alle' the BULL r#le
Figure 21.12 -
Insertion o# the copleted denture
Pre)at#re &onta&ts on the *alan&$n3 s$'e )a. o&r *et-een s#pport$n3 sps +J
Area of interferenc e
Area of suppor t
1-
Figure 21. 13 /
Insertion o# the copleted denture
Balan&$n3 s$'e pre)at#r$t$es sho#l' *e el$)$nate' , -herever poss$*le , *. sele&t$vel. a'#st$n3 the area o% $nter%eren&e rather than the area o% s#pport
!nsertion of t$e completed denture Figure 21. 14 /
lnserlion o# the copleted denture
In protr#s$ve ers$on , 3r$n'$n3 the '$stal %a&$n3 $n&l$nes o% )a$llar. teeth an' )es$al %a&$n3 $n&l$nes o% )an'$*#lar teeth el$)$nates pre)at#re &onta&ts
The patient is invited to .he.5 the appearan.e of the dentures so that any further minor modifi.ation .an be .arried out9 -fter ad6ustments to the dentures have been .ompleted) all areas that have been ground are repolished 9
!nstructions to t$e patient Instru.tions to the patient should be given verbally and also rein for.ed ith a printed sheet9 The e*planation of any e*pe.ted diffi.ulties and limitations of the dentures made at the beginning of treatment should be
Figure 21. 1% /
re$infor.ed9 "espite the provision of retentive elements in the design) mus.ular .ontrol is very impor tant in the su..essful earing of dentures9 1u.h .ontrol ta5es time to develop) so small quantities of non $sti.5y food should be .heed on both sides of the mouth initially9 The patient must be instru.ted in the .orre.t path of insertion and removal of the dentures9 Vulnerable .omponents must be pointed outB thus .lasps should not be $used as fingernail holds during removal9
Instructions to the patient
Deta$le' a'v$&e on 'ent#re h.3$ene sho#l' *e prov$'e' The pat$ent sho#l' *e en&o#ra3e' to &lean all s#r%a&es o% the 'ent#res thoro#3hl. a%ter ever. )eal A s)all/hea'e' )#lt$t#%te' tooth*r#sh has 3oo' a&&ess an' a'apta*$l$t. to )ost o% the s#r%a&es a s$n3le t#%te' +$nterspa&e *r#sh an'or a s)all *ottle/t.pe +$nter'ental *r#sh )a. *e reF#$re' to &lean the %$tt$n3 s#r%a&es o% o&&l#sal rests an' &lasps Soap )a. *e #se' on these *r#shes Ho-ever, so)e pat$ents pre%er to #se toothpaste *e&a#se o% $ts %lavo#r In s#&h &ases, $n%or)at$on on the *ran's that are least a*ras$ve to-ar's a&r.l$& res$n sho#l' *e 3$ven
The patient should be advised that if signifi.ant dis.omfort is The need for .leaning the remaining natural teeth should be stressed9 !arti.ular attenti on shoul d be devoted to all surfa.es e*perien.ed during the first ee5 the dentures should be .overed by the denture9 !atients should be as5ed to bring their removed and should not be orn again until a fe hours before tooth brush to the revie appoin tment so that their brushing the revie appointment9 This short period of ear often aids the lo.ation of the .ause of the pain9 te.hnique .an be monitored and improved if required9 The need for regular revie of the mouth and denture should "is.losing tablets or solutions are useful aids for both patient and dentist to .he.5 the effi.ien.y of .leansing of natural teeth be emphasised9 Not only may the natural teeth and periodontal and dentures9 tissues require treatment) but it is also ne.essary to prevent To avoid fra.ture) dentures should be brushed over a basin dam age from the denture9 =or instan.e) distal e*tension saddles half$full of ater and they should not be squee>ed in the palm of may need to be relined in order to eliminate the ro.5ing the hand9 movement that .ould loosen abutment teeth and hasten loss of "entur es should generally not be orn at night9 ;oever) alveolar bone in the edentulous area9 I t must also be made .lear patients may be advised to do so for the first ee5 to aid that dentures have a limited life and therefore repla.ements ill adap tation9 Immersion .leansers .an be used as an ad6un.t to need to be .on stru.ted as appropriate9 .lean ing) but overnight soa5ing in the hy po.hlorite type may The patient should be given an appointment for revie .ause .orrosion of .obalt .hromium frameor5s9 in appro*imately seven days< time9
1-
--
'evie*
atients must be revieed folloing the fitting of dentures to ensure that the oral tissues are not being damaged and
P
that th e dentures are fun.tional9 -ny ne.essary dentu re ad6ustments are then .arried out9
?irst revie* The first revie ill usually be underta5en about one ee5 after denture insertion9 The patient is as5ed for .omments on this ini tial period of denture$earing and a history is ta5en of any .om plaint9 The most .ommon .omplaints are of pain or looseness) or both 9 @ven if the patient e*presses .omplete satisfa.tion ith the den tures) a .areful e*amination of the mouth is essential9 This is be.ause tissue damage .aused by the dentur e may o..ur 7even e*tensive ul.eration8 in spite of the patient having reported t hat the dentures are entirely .omfortable9 easons for this apparent dis.repan.y may be that the patient possesses a high pain thresh old) or is relu.tant to ris5 offending the dentist9
Information gleaned from the history of any .omplaint together ith the findings on e*amination ill guide the dentist to a diagnosis9 I t is impo rtan t to appre.iate that dis.omfort and mu.osal in6ury .aused by the denture may be due either to faults relating to the impression surfa.e or to the o..lusal surfa.e9 I t is easy to fall into the trap of .on.luding that mu.osaO damage in a parti. ular instan.e is due to an error in the impression surfa.e hen this $n fa.t is not the .ase) the danger being that ill$advised ad6ust ment of that surfa.e ill almost .ertainly aggravate the situation9 @rrors in the o..lusion .hara.teristi.ally .ause relatively dif fuse mu.osal damage9 ;oever) this is not alays the .ase as other fa.tors su.h as ridge morphology may serve to lo.alise the effe.ts of o..lusal overload9 =or this reason) the o..lusion must alays be .arefully assessed and the impression surfa.e must never be ad6usted empiri.ally9 -ssessment of bot h the impres sion and o..lusal surfa.es ill be made employing the pro.edures outlined in .hapters /+ and 2/9
!mpression surface faults Figure 22. 1 /
Ipression sur#ace #aults
S$n&e the #l&er $n the le%t lo-er *#&&al s#ls $s relate' to the 'ent#re *or'er, the &a#se $s )ost l$kel. to *e over/etens$on (here v$s$*$l$t. $s 3oo' the o%%en'$n3 area o% over /etens$on &an #s#all. *e eas$l. $'ent$%$e' an' &orre&te' Ho-ever, v$s$*$l$t. ) a. *e poor $n the poster$or re3$on o% the )o#th so that press#re/sens$t$ve '$s&los$n3 )e'$a )a. *e nee'e' to ens#re a&rate lo&at$on o% the area o% %lan3e reF#$r$n3 a'#st)ent
1-
A clinical guide to removable partial dentures Figure 22.2 -
I I
Ipression sur#ace #aults
Ul&erat$on o% the )ost *#l*o#s part o% an #n'ert r$'3e $s &hara&ter$st$& o% $na'eF#ate rel$e% o% the #n'ert area res#lt$n3 $n tra#)a to the )#&osa -hen the 'ent#re $s $nserte' or re)ove' The ro#t$ne #se o% a press#re $n'$&at$n3 paste or -a to $'ent$%. the area o% $)press$on s#r%a&e $nvolve' $s re&o))en'e' !ther &a#ses o% lo&al$se' )#&osal $n#r. *eneath the $)press$on s#r%a&e are a&r.l$& pearls, or press#re po$nts res#lt$n3 %ro) a 'a) a3e' &ast or $na&rate $)press$on
I
"cclusal surface faults Figure 22 .3 -
+cclusal sur#ace #aults
La&k o% even &onta&t $n $nterspal pos$t$on -$ll loa' the s#pport$n3 t$ss#es #nevenl. as $n th$s ea)ple o% a '$stal etens$on sa''le 'ent#re -$th a pre)at#re &onta&t $n the se&on' )olar re3$on !&&l#sal $nter%eren&e $n lateral an' protr#s$ve ers$ons &an '$spla&e the 'ent#re an' th#s tra#)at$se the s#pport$n3 t$ss#es !&&l#sal errors &an also &a#se %a&$al '$s&o)%ort an' ten'erness $n the )#s&les o% )ast$&at$on as a res#lt o% the )an'$*le )anoe#vr$n3 to avo$' the $nter%eren&es
!ain originating from the periodontal ligaments of teeth .on ta.ting the denture .an arise from the appli.ation of e*.essive for.e either as the result of o..lusal errors) or ina..ura.ies in the fit of the denture9 n rare o..asions pulpal p ain may result from galvani. a.tion as a .onsequen.e of .onta.t beteen a ne metal
frameor5 and a freshly inserted amalgam restoration9 The pain usually de.reases ith the passage of time as the surfa.e of the amalgam tarnishes and the pulpal hyperaemia 7.onsequent upon .avity preparation 8 subsides9
Plaue and denture control Figure 22.4 /
Pla&ue control
A r easses s)ent o% the pat$ent2s oral an' ' ent#re h.3$ene %or)s an essent$al part o% the rev$e- appo$nt)ent D$s&los$n3 ta*lets or sol#t$on &an *e #se' to sta$n the plaF#e on the re)a$n$n3 nat#ral teeth D$s&los$n3 sol#t$on $s *est %or the 'ent#res as $t &an *e &onven$entl. appl$e' to the $)press$on s#r%a&e as -ell as the pol$she' s#r% a&e , as seen here The opport#n$t. )a. then *e taken to re$n%or&e the a'v$&e on plaF#e &ontrol alrea'. 3$ ven It )a. *e ne&essar. to )o'$%. the &lean$n3 te&hn$F#e $% the pat$ent has o*v$o#s '$%%$lt. $n re)ov$n3 plaF#e %ro) &erta$n areas
13 0
'evie* Figure 22. # $ 'enture control Dent#res -hose retent$on 'epen's pr$)ar$l. on &ontrol *. the pat$ent2s )#slat#re )a. *e reporte' as *e$n3 loose $% the pat$ent has not .et 'evelope' the ne&essar. sk$lls #rther a'v$&e an' en&o#ra3e)ent )a. have to *e 3$ven at th$s sta3e
4ubseuent revie*s I % anything more than very minor tissue damage is noted at the first revie an additional appointment may be required to ensure that healing has ta5en pla.e9 I % the patient is slo to a.quire the neuromus.ular s5ills ne. essary for retention) it may be possible to modify the denture to in.rease physi.al retention 9 "ire.t retention .an sometimes be improved by adding a rought .lasp) andKor by modifying tooth .ontour by a.id $ et.h .omposite additions 7=igure /#92#89
enture maintenance n.e problems arising dire.tly after insertion of a denture have been resolved) regular inspe.tion and maintenan.e of the den ture is underta5en as part of the patient
Figure 22.6 /
nless there are regular inspe.tions the denture .an .ause .on siderable damage hi.h) at least in the early stages) may be symp tomlessB therefore the patient ould not ne.essarily be aare that treatment is required9 I t is thus essential that hen the dentures have been fitted the need for regular re.all appointments is emphasised to the patient9 ontinued alveolar resorption) usually most mar5ed under mandibular distal e*tension saddles) progressively redu.es mu.osal support for dentures9 hen the effe.t of this on oral health and fun.tion is 6udged to be .lini.ally signifi.ant) a rebase to .orre.t the la.5 of fit is indi.ated9 The .lini.al pro.edure fol los the prin.iples laid don in .hapter /,9 Maintenan.e may also) from time to time) involve repairs and additions to the dentures as des.ribed in .hapter /09
'enture aintenance
La&k o% )a$ntenan&e an' re3#lar $nspe&t$on $n th$s &ase has lea' to e&ess$ve plaF#e a&)#lat$on, 3$n3$val $n%la))at$on an' a 'e3ree o% str$pp$n3 o% the 3$n3$vae %ro) the l$n3#al aspe&ts o% the nat#ral teeth
Figure 22 . ' $
'enture aintenance
I% alveolar resorpt$on $s a&&o)pan$e' *. -ear o% the o&&l#sal s#r%a&e o% the a&r.l$& res$n art$%$&$al teeth , the 'eran3e' o&&l#s$on -$ll a&&elerate t$ss#e 'a)a3e S$)ple re*as$n3 o% the sa''les -$ll not restore the &orre&t o&&l#sal &onta&ts the teeth &an e$ther *e repla&e' or the 'ent#res re)a'e
13 1
A clinical guide to removable partial dentures Figure 22." /
'enture aintenance
The ro#t$ne oral rev$e- appo$nt)ents are #se' to )on$tor the pat$ent2s level o% plaF#e &ontrol an ' to re$n%or&e th$s -hen ne&essar. Ina'eF#ate 'ent#re an' oral h.3$ene &an hasten the loss o% nat#ral teeth *. &ar$es an' per$o'ontal '$sease an' )a. &ontr$*#te to 'ent#re an' an3#lar sto)at$t$s
Postscript To .ontrasting .lini.al situations are offered at the end of this final .hapter9
F i g u r e
2 2 9 , $ P o s t s c r i p t No one -o#l' 'en. that the lon3/ter) treat)ent o% th$s pat$ent has %a$le' ent$rel. Man. teeth have *een 'a)a3e' as a res#lt o% -ear$n3 an RPD that repla&e' #st one tooth a h$3h *$olo3$&al pr$&e has *een pa$'
Figure 22 . 1+a /
Postscript
Th$s %avo#ra*le t$ss#e rea&t$on to a )a$llar. RPD $s $n stark &ontrast to that sho-n $n the prev$o#s %$3#re The pat$ent -as $n her )$'/ sevent$es an' ha' -orn the sa)e 'ent#re %or 5: .ears The *$olo3$&al pr$&e has *een ver. lo-
13 -
Figure 229 1+b /
Postscript
Th$s e&ellent treat)ent o#t&o)e has res#lte' %ro) The pat$ent )a$nta$n$n3 a h$3h level o% plaF#e &ontrol The 'ent$st 'es$3n$n3 the 'ent#re to &o)pl. -$th the *as$& pr$n&$ples, -h$&h %avo#r a health. t$ss#e rea&t$on, an' #n'ertak$n3 appropr$ate &l$n$&al pro&e'#res -$th pre&$s$on The 'ental te&hn$&$an %ollo-$n3 these 'es$3n pr$n&$ples %a$th%#ll. , an' appl.$n3 epert kno-le'3e an' sk$ll to pro'#&e an RPD o% 3oo' F#al$t. Goo' &o))#n$&at$on *et-een the 'ent$st , the pat$ent an' the 'ental te&hn$&$an