- Email: [email protected]
Use of a posterior composite resin to restore teeth and support enamel: report of case
C L I N I C A L
R E P O R T S
Use of a posterior composite resin to restore teeth and support enamel: report of case H . K e ith H e r r in , D D S
A case in w hich an am algam resto ra tio n is rep la ced w ith a p o ste rio r com posite resin resto ra tio n etched a n d bonded to the enam el is re p o rted , a n d the technique used to p r e ven t p u lp a l ir rita tio n a fte r the restoration is p la c e d is discussed.
b o n d e d c o m p o s ite r e s in p r o c e d u r e show ed significantly h ig h e r cuspal re in fo rc em e n t th a n did the n o n b o n d ed p ro cedure. A case is p resen ted in w hich an attem p t is m ade to reconcile ap p e aran c e o f th e res toratio n , cost o f th e p ro ce d u re , an d p ro tection o f th e u n su p p o rte d to o th stru c tu re .
Report of case
h e d em an d o n th e p a rt o f th e p u b lic fo r a m ore esthetic posterior resto ratio n has resulted in the d e velo p m en t an d use o f com posite resins for resto rin g p o sterio r teeth. In selected cases in w hich m axillary p o sterio r teeth have been discolored by large, d eep , am algam resto ratio n s, the placing o f posterio r com posite resins may be considered as an al te rn a tiv e to o th e r fo rm s o f tre a tm e n t w hen ap p e aran c e is im p o rta n t to th e p a tien t a n d w hen th e ex pense o f full cover age is a consideration. O ften , w hen the existing am algam is rem o v e d , th e buccal to o th stru c tu re is fo u n d to be u n su p p o rted . A lthough th e buccal cusps o f m axillary m olars an d p re m olars a re n o t the w orking cusps except in th e Class I II restoration, th e buccal side o f th e to o th is co nsidered to be w eakened if th e cusps a re u n su p p o rte d by sound d e n tin .1 M orin a n d o th e rs2 re p o rte d th a t a
T
T h e patient was a 24-year-old male with a Class I amalgam restoration in the maxillary right first molar. T he occlusal table o f the restoration was wide, particularly in the buccal extension. A radiograph showed that the restoration had a d eep pulpal floor but no periapical pathologic conditions. T he periodontal condition o f the tooth was ju d g ed to be good. A fter the onset o f
Fig 1 ■ Maxillary right first molar with the amalgam restoration removed. The discolored, sclerotic dentin was left on the pulpal floor after bein g checked to ensure that no caries was present.
infiltration anesthesia, the q u ad ran t was iso lated with a ru b b er dam and the existing amal gam was removed with a no. 245 carbide bur. A fter the removal o f the amalgam restoration and liner, the discolored tooth structure and stain were rem oved from the buccal walls o f the cavity p rep aratio n (Fig I). T h e discolored, sclerotic dentin was left on the pulpal floor after being checked to ensure that no caries was p re sent. Instead o f using a calcium hydroxide liner, a glass ionom er lining cem ent was used. If there had been a pulp exposure or a suspected micro scopic pulp exposure o r if the pulp had been visible un derneath a thin layer o f dentin, a layer o f calcium hydroxide would have been placed in the immediate area. T h e calcium hydroxide liner protects the pulp when the sm ear layer is rem oved partially 3 and provides optim um chemical bonding o f the glass ionom er lining cem ent to the dentin. T he next step is to mois ten a cotton pledget with a d ro p o f the liquid portion o f polyacrylic acid (Durelon cement) and apply it to the exposed dentinal surfaces for 5 seconds. T h e polyacrylic acid will rem ove the sm ear layer without opening the ends o f the tubules and causing possible pulpal irritation (E. A. Berry III, DDS, personal comm unica tio n , U n iv ersity o f T e x a s H e a lth Science Center, Dental Branch, H ouston, 1985.) Mod ifying the sm ear layer in dentin improves the chemical bond between glass ionom er and den tin.4 T h e polyacrylic acid is rem oved with a gen tle stream o f water and the tooth is dried but not desiccated. A glass ionom er liningcem ent (G. C. Glass Ionom er Lining Cement) is then mixed according to the m anufacturer’s instructions, and a thick layer, covering all dentinal surfaces is applied with an applicator (Dycal) (Fig 2). JADA, Vol. 112, June 1986 ■ 845
CLINICAL
REPORTS
7 he glass ionomer lining cement will provide adequate protection of the pulp from the irritating effects of the bonding agent and composite resin.
A fter the glass ionom er lining cem ent is set, the enam el cavo su rface is bev ele d . N ext, th e enamel and the glass ionom er lining cem ent are etched for 1 minute with an etching gel. T h e gel is rinsed with a gentle stream o f water for 45 seconds and then the tooth is dried. A lightactivated bonding agent (Bondlite) is applied with a clean brush to all cavosurface margins,
eliminate cavosurface m icrogaps that m ight cause pulpal sensitivity after treatm ent as a re sult o f microleakage7,8 (Fig 3).
resto ratio n th a t is m ore resistant to caries
Discussion
In selected cases in w hich ap p e aran c e i im p o rta n t, a p o ste rio r com posite resir m ay be used successfully to rein fo rce an< resto re a tooth with u n d e rm in e d , non fu nctional cusps. T h e resto ratio n o f teetl with com prom ised fu n ctio n al cusps is no re c o m m e n d e d . O n ce th e d ecisio n h a been m ad e to resto re th e to o th with a pos te rio r com posite resin, care m ust be takei to follow a technique to p rev e n t problem a fte r tre a tm e n t th a t resu lt fro m micro leakage an d co ntraction shrinkage.
P osterior com posite resins req u ire exact ing applicatio n , an d a tte n tio n m ust be
Summary
---------------------------------J ! i O A ------------------------------------T h e a u th o r has n o financial, econom ic, o r profes sional in terest in any o f th e p ro d u c ts n am ed in thi re p o rt.
Fig 2 ■ Glass ionomer lining cement covering the dentinal surfaces. After the glass ionomer lining cement is set, the enamel cavosurface is beveled.
internal enamel surfaces, and the etched glass ionom er surface. T h e etched glass ionom er sur face increases the mechanical bond o f the bond ing agent to the glass ionom er lining cement. A gentle stream o f air is used to ensure a thin, uniform coating o f bonding agent on all desired surfaces. T h e bonding agent then is light cured for 10 seconds. A condensable posterior com posite resin (Herculite) is used with an incre m ental fill technique to restore the tooth. To reduce curing shrinkage, the incremental fill and cure technique is favored over a bulk fill technique. T he increm ental fill and cure tech nique reduces the curing shrinkage that might cause the material to pull away from the cavity walls and, thereby, increase microleakage and minimize the bonding together o f weakened areas o f the tooth.5 Each increm ent is cured for 40 seconds.6 A fter the final increm ent is cured but before final finishing and polishing o f the restoration, the tooth at the cavosurfaces is etched again for 1 m inute and the margins covered with the light-activated bonding agent. This step ensures that the margins are sealed to
846 ■ JADA, Vol. 112, June 1986
Fig 3 ■ The finished restoration. The margins have been sealed to eliminate cavosurface mi crogaps that might cause pulpal sensitivity be cause o f microleakage after the restoration has been placed.
paid to detail if the desired results a re to be achieved. In this case, it is believed th a t the u n s u p p o r te d b u ccal c u sp s h a v e b ee n stre n g th e n e d an d th a t a p p e a ra n c e has b e e n im p r o v e d . T h e u se o f a g la ss io n o m er lining cem ent im proves a p p e a r ance m ore th an th e use o f a calcium hy d r o x id e ty p e o f l i n e r b e c a u s e g lass io n o m er lining cem ents have a m inim al effect on th e shade o f th e com posite resin. T h e glass io n o m er lining cem en t also will provide adeq u ate p ro tectio n o f th e p ulp from th e irritatin g effects o f th e b o n d in g ag en t and com posite resin. E tching the glass ionom er lining cem en t o ffers an ad ditional advantage over th e calcium hy dro x id e liner because etch in g th e glass ionom er results in a ro u g h surface th a t provides a m eans o f m echanical retention o f th e b o n d in g ag en t to th e glass ionom er. Also, the slow release o f flu o rid e from glass ionom er cem ents9 may resu lt in a
D r. H e rrin is assistant p ro fesso r, o p erativ e den tistry, U niversity o f T ex as H e alth Science C enter D ental B ran ch , 6515 J o h n F ree m a n Ave, PO Bo 20068, H o u sto n , 77225. A ddress req u ests fo r re p rin t to th e a u th o r. 1. S tu rd ev an t, C.M ., an d o th e rs, eds. T h e a rt ant science o f op erativ e d en tistry , e d 2. St. Louis, C. V M osby C o, 1985, p 98. 2. M orin, D.; D eLong, R.; a n d D ouglas, W .H . Cusj re in fo rce m e n t by th e acid-etch tech n iq u e. J D ent Re 63(8): 1075-1078, 1984. 3. B aum , L.; Phillips, R.W .; a n d L u n d , M .R., eds T ex tb o o k o f o p erativ e d en tistry , ed 2. Philadelphia W. B. S a u n d e rs Co, 1985, p 123. 4. M cL ean, J.W .; P rosser, H .J.; a n d W ilson, A.D T h e use o f glass-ionom er cem en ts in b o n d in g com pos ite resins to d e n tin . B r D en t J 158:410-414, 1985. 5. Jo rg e n se n , K.D., a n d H isam itsu, H. Composite resto ratio n s: p rev en tio n in vitro o f c o n tractio n gaps. D en t Res 63(2): 141-145, 1984. 6. Sw artz, M.L.; Phillips, R.W .; a n d R hodes, B. Vis ible lig h t-ac tiv a te d resin s— d e p th o f c u re . J A D / 106(5):634-637, 1983. 7. Q vist, V. M arginal ad ap tatio n o f com posite res to ra tio n s p e rfo rm e d in vivo w ith d iffe re n t acid-etcl restorative p ro ced u res. Scand I D en t Res 93:68-75 1985. 8. T o rste n so n , B.; B ra n n stro m , M.; a n d M attson B. A new m eth o d fo r sealing com posite resin contrac tion gaps in lined cavities. J D en t Res 64(3):450-453 1985. 9. Sw artz, M.L.; Phillips, R.W .; an d C lark, H.E L o n g -term F release fro m glass io n o m er cem ents. D en t Res 63(2): 158-160, 1984.
R E P O R T S
Use of a posterior composite resin to restore teeth and support enamel: report of case H . K e ith H e r r in , D D S
A case in w hich an am algam resto ra tio n is rep la ced w ith a p o ste rio r com posite resin resto ra tio n etched a n d bonded to the enam el is re p o rted , a n d the technique used to p r e ven t p u lp a l ir rita tio n a fte r the restoration is p la c e d is discussed.
b o n d e d c o m p o s ite r e s in p r o c e d u r e show ed significantly h ig h e r cuspal re in fo rc em e n t th a n did the n o n b o n d ed p ro cedure. A case is p resen ted in w hich an attem p t is m ade to reconcile ap p e aran c e o f th e res toratio n , cost o f th e p ro ce d u re , an d p ro tection o f th e u n su p p o rte d to o th stru c tu re .
Report of case
h e d em an d o n th e p a rt o f th e p u b lic fo r a m ore esthetic posterior resto ratio n has resulted in the d e velo p m en t an d use o f com posite resins for resto rin g p o sterio r teeth. In selected cases in w hich m axillary p o sterio r teeth have been discolored by large, d eep , am algam resto ratio n s, the placing o f posterio r com posite resins may be considered as an al te rn a tiv e to o th e r fo rm s o f tre a tm e n t w hen ap p e aran c e is im p o rta n t to th e p a tien t a n d w hen th e ex pense o f full cover age is a consideration. O ften , w hen the existing am algam is rem o v e d , th e buccal to o th stru c tu re is fo u n d to be u n su p p o rted . A lthough th e buccal cusps o f m axillary m olars an d p re m olars a re n o t the w orking cusps except in th e Class I II restoration, th e buccal side o f th e to o th is co nsidered to be w eakened if th e cusps a re u n su p p o rte d by sound d e n tin .1 M orin a n d o th e rs2 re p o rte d th a t a
T
T h e patient was a 24-year-old male with a Class I amalgam restoration in the maxillary right first molar. T he occlusal table o f the restoration was wide, particularly in the buccal extension. A radiograph showed that the restoration had a d eep pulpal floor but no periapical pathologic conditions. T he periodontal condition o f the tooth was ju d g ed to be good. A fter the onset o f
Fig 1 ■ Maxillary right first molar with the amalgam restoration removed. The discolored, sclerotic dentin was left on the pulpal floor after bein g checked to ensure that no caries was present.
infiltration anesthesia, the q u ad ran t was iso lated with a ru b b er dam and the existing amal gam was removed with a no. 245 carbide bur. A fter the removal o f the amalgam restoration and liner, the discolored tooth structure and stain were rem oved from the buccal walls o f the cavity p rep aratio n (Fig I). T h e discolored, sclerotic dentin was left on the pulpal floor after being checked to ensure that no caries was p re sent. Instead o f using a calcium hydroxide liner, a glass ionom er lining cem ent was used. If there had been a pulp exposure or a suspected micro scopic pulp exposure o r if the pulp had been visible un derneath a thin layer o f dentin, a layer o f calcium hydroxide would have been placed in the immediate area. T h e calcium hydroxide liner protects the pulp when the sm ear layer is rem oved partially 3 and provides optim um chemical bonding o f the glass ionom er lining cem ent to the dentin. T he next step is to mois ten a cotton pledget with a d ro p o f the liquid portion o f polyacrylic acid (Durelon cement) and apply it to the exposed dentinal surfaces for 5 seconds. T h e polyacrylic acid will rem ove the sm ear layer without opening the ends o f the tubules and causing possible pulpal irritation (E. A. Berry III, DDS, personal comm unica tio n , U n iv ersity o f T e x a s H e a lth Science Center, Dental Branch, H ouston, 1985.) Mod ifying the sm ear layer in dentin improves the chemical bond between glass ionom er and den tin.4 T h e polyacrylic acid is rem oved with a gen tle stream o f water and the tooth is dried but not desiccated. A glass ionom er liningcem ent (G. C. Glass Ionom er Lining Cement) is then mixed according to the m anufacturer’s instructions, and a thick layer, covering all dentinal surfaces is applied with an applicator (Dycal) (Fig 2). JADA, Vol. 112, June 1986 ■ 845
CLINICAL
REPORTS
7 he glass ionomer lining cement will provide adequate protection of the pulp from the irritating effects of the bonding agent and composite resin.
A fter the glass ionom er lining cem ent is set, the enam el cavo su rface is bev ele d . N ext, th e enamel and the glass ionom er lining cem ent are etched for 1 minute with an etching gel. T h e gel is rinsed with a gentle stream o f water for 45 seconds and then the tooth is dried. A lightactivated bonding agent (Bondlite) is applied with a clean brush to all cavosurface margins,
eliminate cavosurface m icrogaps that m ight cause pulpal sensitivity after treatm ent as a re sult o f microleakage7,8 (Fig 3).
resto ratio n th a t is m ore resistant to caries
Discussion
In selected cases in w hich ap p e aran c e i im p o rta n t, a p o ste rio r com posite resir m ay be used successfully to rein fo rce an< resto re a tooth with u n d e rm in e d , non fu nctional cusps. T h e resto ratio n o f teetl with com prom ised fu n ctio n al cusps is no re c o m m e n d e d . O n ce th e d ecisio n h a been m ad e to resto re th e to o th with a pos te rio r com posite resin, care m ust be takei to follow a technique to p rev e n t problem a fte r tre a tm e n t th a t resu lt fro m micro leakage an d co ntraction shrinkage.
P osterior com posite resins req u ire exact ing applicatio n , an d a tte n tio n m ust be
Summary
---------------------------------J ! i O A ------------------------------------T h e a u th o r has n o financial, econom ic, o r profes sional in terest in any o f th e p ro d u c ts n am ed in thi re p o rt.
Fig 2 ■ Glass ionomer lining cement covering the dentinal surfaces. After the glass ionomer lining cement is set, the enamel cavosurface is beveled.
internal enamel surfaces, and the etched glass ionom er surface. T h e etched glass ionom er sur face increases the mechanical bond o f the bond ing agent to the glass ionom er lining cement. A gentle stream o f air is used to ensure a thin, uniform coating o f bonding agent on all desired surfaces. T h e bonding agent then is light cured for 10 seconds. A condensable posterior com posite resin (Herculite) is used with an incre m ental fill technique to restore the tooth. To reduce curing shrinkage, the incremental fill and cure technique is favored over a bulk fill technique. T he increm ental fill and cure tech nique reduces the curing shrinkage that might cause the material to pull away from the cavity walls and, thereby, increase microleakage and minimize the bonding together o f weakened areas o f the tooth.5 Each increm ent is cured for 40 seconds.6 A fter the final increm ent is cured but before final finishing and polishing o f the restoration, the tooth at the cavosurfaces is etched again for 1 m inute and the margins covered with the light-activated bonding agent. This step ensures that the margins are sealed to
846 ■ JADA, Vol. 112, June 1986
Fig 3 ■ The finished restoration. The margins have been sealed to eliminate cavosurface mi crogaps that might cause pulpal sensitivity be cause o f microleakage after the restoration has been placed.
paid to detail if the desired results a re to be achieved. In this case, it is believed th a t the u n s u p p o r te d b u ccal c u sp s h a v e b ee n stre n g th e n e d an d th a t a p p e a ra n c e has b e e n im p r o v e d . T h e u se o f a g la ss io n o m er lining cem ent im proves a p p e a r ance m ore th an th e use o f a calcium hy d r o x id e ty p e o f l i n e r b e c a u s e g lass io n o m er lining cem ents have a m inim al effect on th e shade o f th e com posite resin. T h e glass io n o m er lining cem en t also will provide adeq u ate p ro tectio n o f th e p ulp from th e irritatin g effects o f th e b o n d in g ag en t and com posite resin. E tching the glass ionom er lining cem en t o ffers an ad ditional advantage over th e calcium hy dro x id e liner because etch in g th e glass ionom er results in a ro u g h surface th a t provides a m eans o f m echanical retention o f th e b o n d in g ag en t to th e glass ionom er. Also, the slow release o f flu o rid e from glass ionom er cem ents9 may resu lt in a
D r. H e rrin is assistant p ro fesso r, o p erativ e den tistry, U niversity o f T ex as H e alth Science C enter D ental B ran ch , 6515 J o h n F ree m a n Ave, PO Bo 20068, H o u sto n , 77225. A ddress req u ests fo r re p rin t to th e a u th o r. 1. S tu rd ev an t, C.M ., an d o th e rs, eds. T h e a rt ant science o f op erativ e d en tistry , e d 2. St. Louis, C. V M osby C o, 1985, p 98. 2. M orin, D.; D eLong, R.; a n d D ouglas, W .H . Cusj re in fo rce m e n t by th e acid-etch tech n iq u e. J D ent Re 63(8): 1075-1078, 1984. 3. B aum , L.; Phillips, R.W .; a n d L u n d , M .R., eds T ex tb o o k o f o p erativ e d en tistry , ed 2. Philadelphia W. B. S a u n d e rs Co, 1985, p 123. 4. M cL ean, J.W .; P rosser, H .J.; a n d W ilson, A.D T h e use o f glass-ionom er cem en ts in b o n d in g com pos ite resins to d e n tin . B r D en t J 158:410-414, 1985. 5. Jo rg e n se n , K.D., a n d H isam itsu, H. Composite resto ratio n s: p rev en tio n in vitro o f c o n tractio n gaps. D en t Res 63(2): 141-145, 1984. 6. Sw artz, M.L.; Phillips, R.W .; a n d R hodes, B. Vis ible lig h t-ac tiv a te d resin s— d e p th o f c u re . J A D / 106(5):634-637, 1983. 7. Q vist, V. M arginal ad ap tatio n o f com posite res to ra tio n s p e rfo rm e d in vivo w ith d iffe re n t acid-etcl restorative p ro ced u res. Scand I D en t Res 93:68-75 1985. 8. T o rste n so n , B.; B ra n n stro m , M.; a n d M attson B. A new m eth o d fo r sealing com posite resin contrac tion gaps in lined cavities. J D en t Res 64(3):450-453 1985. 9. Sw artz, M.L.; Phillips, R.W .; an d C lark, H.E L o n g -term F release fro m glass io n o m er cem ents. D en t Res 63(2): 158-160, 1984.