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Restoring a Tooth with Massive Internal Resorption to Form and Function: Report of Case
__________J € ! A __________ C L I N I C A L
T E C H N I Q U E S
Restoring a tooth with massive internal resorption to form and function: report of case H . Keith H errin, DDS; J o h n R. L udington, Jr., DDS, MSD
This case report describes an innovative restorative technique using glass ionomer and posterior composite resin materials. It was used to treat a patient with extensive internal resorption of the clinical crown of the maxil lary first molar. Although unconventional, this method successfully strengthened and restored the tooth.
he prim ary goal o f endodontics, restorative dentistry, and dentistry in general is to m aintain the den tition in a physiologically functional state fo r oral an d systemic h e a lth .1 Achieving this goal in teeth that have extensive inter nal reso rp tio n m akes e n d o d o n tic tre a t m e n t c o m p lic ate d an d resto rativ e co n siderations difficult. T h is a r tic le p r e s e n ts a r e p o r t o f a p atien t with a m axillary first m olar con ta in in g an e x te n s iv e a r e a o f in te r n a l resorption in the clinical crown. Although resorption o f this m agnitude com plicated the endodontic treatm ent, it also required an innovative restorative approach using glass io n o m e r an d p o s te rio r com posite resin materials.
T
Report of case T he patient, a 30-year-old white m ale in e x c e lle n t h e a lth , was firs t seen in July
1985. H e stated th at his m axillary righ t m olars “w ere n o t feelin g rig h t.” Radiographic evidence showed a large radioluc e n t a r e a in th e d is ta l a s p e c t o f th e anatom ic crown of the maxillary right first molar. T he p atie n t could n o t relate any traum a to the tooth except that in 1980, w hile an o ral s u rg e ry re s id e n t, h e d id slightly chip the distolingual cusp o f that tooth when he was biting on a bite force strain gauge. No carious lesions o r existing resto ra tions were detected in the rem aining den titio n . All te e th in th e m a x illa ry rig h t q u ad ran t resp o nd ed to cold in a norm al m a n n e r an d n o n e o f th e te e th in this quadrant was sensitive to percussion. Clini cal visual ex a m in a tio n o f th e m axillary
r ig h t first m o la r show ed no d e te c ta b le b rea k s in th e to o th su rface to in d ic ate caries o r a perforation associated with the large radiolucent area in the crown. A pre lim inary diagnosis o f in tern al resorption was m ade. T he patient was advised to have endodontic treatm ent, b u t he elected not to have treatm en t at that time. T h ree m o n ths later the involved tooth was again radiographed, and the tooth was still a s y m p to m a tic (F ig 1). A gain th e patient elected to forgo endodontic treat ment. In M arch 1986, a radiograph indicated th a t th e ra d io lu c e n t area was som ew hat larger; however, p erforatio n through the d e n tin , c e m e n tu m , o r e n a m e l was n o t seen (Fig 2 ). Im m e d ia te , co n serv ativ e
Fig 1 ■ P eria p ic a l ra d io g ra p h , m axillary rig h t
Fig 2 ■ Bitewing rad io g rap h showing ex ten t o f
first m olar, 3 m onths a fte r original diagnosis o f
in tern al reso rp tio n , 8 m onths a fte r original diag
internal resorption.
nosis o f internal resorption.
JADA, Vol. 121, A ugust 1990 ■ 271
C L I N I C A L
T E C H N I Q U E S
endodontic treatm en t was recom m ended. In p la n n in g tre a tm e n t for the patient, consideration was given to th e possibility o f p roducing a p erforation either on the distal aspect o f the anatom ic crown or in the furcation area. A perforation in either area would fu rth e r com plicate treatm ent. C o n s id e ra tio n o f how th e to o th w ould later be resto re d was also discussed with the patient at this time. In April, nonsurgical endodontic treat m en t was started. After the onset of infil tratio n anesthesia, the tooth was isolated w ith a r u b b e r d am . A ccess to the p u lp c h a m b e r a n d re s o rb e d a re a was d o n e . Tissue was rem o v ed fro m each of these
Fig 3 ■ P h o tom icrograph o f pulp tissue showing in fla m m a tio n a n d fo c a l h e m o r r h a g e (H & E) stain, orig m ag x 50).
F ig
4 ■
P h o to m ic r o g r a p h
fro m
a re a
of
re s p o rtio n show ing g ran u latio n tissu e with focal h em orrhag e (H & E) stain, o rig mag x 50).
Fig 5 ■ P e ria p ic a l ra d io g ra p h , m ax illary rig h t first m olar, showing co m p leted endodontic treat m ent.
272 ■ JADA, Vol. 121, A ugust 1990
areas and subm itted for histologic exami nation (Fig 3, 4). H em o rrh ag e from the distal an d palatal aspect o f the reso rb ed area o f the crown was difficult to control. C alciu m h y d ro x id e p o w d e r (P u lp d e n t C o r p o r a tio n o f A m e ric a ) U .S.P. was p a c k e d in to th e p u lp c h a m b e r a n d resorbed area to aid in hem o rrh ag e con tr o l. A n IRM te m p o r a r y r e s to r a tio n (C a u lk /D e n ts p ly ) was p la c e d a n d th e reappointm en t for 1 week later was made. T he p a tie n t rem a in ed asym ptom atic. At the second ap p o in tm e n t, the tem p o rary restoration was rem oved u n d e r a ru b b er dam . T h e rem a in in g calcium hydroxide was re m o v e d fro m th e p u lp c h a m b e r, resorbed areas, and canals. T h ere was no h e m o r r h a g e . T h e p u lp c h a m b e r a n d resorbed area were inspected for signs of perforation. N one was found. T he instru m entation was com pleted. T he canals were then obturated with gutta-percha an d zinc oxide-eugenol sealer (Fig 5). T he patient rem ained asymptomatic. Two w eek s a f te r c o m p le tio n o f th e e n d o d o n t ic tr e a tm e n t, th e to o th was resto re d with use o f an innovative tech n iq u e A p o s t a n d c o r e o r a m a lg a m buildup, using pins, was elim in ated as a treatm ent option because o f the proximity of the resorbed areas to the distal cemento e n am e l ju n c tio n a n d to th e fu rc atio n area at the floor o f the pulp chamber. The resorption had o ccurred prim arily in the d istal a n d ap ica l h a lf o f th e a n a to m ic crown. W ith the exception of the conser vative endod o n tic access preparation, the o cclusal su rface o f th e to o th re m a in e d intact. T here was am ple dentin support for all cusps. R e je ctin g a full v e n e e r crow n, again b e c a u s e o f th e clo se p ro x im ity o f th e r e s o r p tio n to th e d istal su rfa c e o f th e tooth, a decision was m ade to restore the tooth with posterior com posite resin and glass io n o m e r lin in g ce m e n t co n tain in g am algam filings. T h e tem p o rary resto ra tio n was r e m o v e d a n d th e p u lp ch a m b e r/re so rb e d area carefully cleaned with a large diam eter ro u n d bur. All inte r io r aspects o f th e to o th w ere carefully inspected T he dentinal surfaces were then tre a te d fo r 20 se co n d s w ith polyacrylic acid (D urelo n liquid, P rem ier) to o p en th e d e n tin a l tu b u le s 2 a n d rem o v e th e sm ear layer. T h e pulp ch a m b e r/ resorbed are a was ap p ro x im ately tw o-thirds filled with the glass ionomer-amalgam filing mix tu re a n d allow ed to set. Because o f th e dark color o f this m aterial, it was decided to m ask it w ith a glass io n o m e r lu tin g cem ent before final restoration with a pos terior com posite m aterial (Fig 6) After the
lining cem ent was set, the enam el cavosurfaces were beveled and etched. T he tooth was th en filled increm entally to minimize any forces on the tooth generated by poly m e riz a tio n sh rin k a g e .3 A fter all excess com posite was removed from the cavosurfaces, the cavosurfaces were re-etched and flow ed w ith c lea r a u to -c u re d se ala n t to m inim ize any en am el cav o su rface/co m p o s ite d e f e c ts .2 T h e r u b b e r d a m was rem oved and the occlusion adjusted (Fig 7).
A 1-year follow-up (Fig 8) showed th a t the treatm en t m ethod chosen has restored th e to o th to fu n ctio n with only a slight d e t e r i o r a t i o n in e s th e tic a p p e a r a n c e c au sed by so m e d isc o lo ratio n from th e glass ionomer-amalgam filing cem ent used to restore the cham ber an d resorbed. Discussion From an e n d o d o n tic p o in t of view, this case p resen ts several interesting findings First, the cause o f the internal resorption is speculative. Rabinowitch4 classified inter nal re so rp tio n in p e rm a n e n t te e th in to fo u r types: id io p a th ic , p erip h e ra l, tra u matic, an d high-speed tooth preparation. T he m ost likely cause in the case rep o rted h ere is traum a. A lthough resorption as a result of traum a is generally seen in ante rior teeth, posterior teeth can also be trau m atized . W hen th e p a tie n t ch ip p e d his tooth by biting on a strain gauge, a certain am o u n t o f traum a was tran sferred to the pulp. Walton and L eonard5 proposed that a crack may in itiate in te rn al reso rp tio n , thus reinforcing the idea o f an underlying cause fo r in te rn a l reso rp tio n , nam ely a com m unication to the oral environm ent. F ahad an d T aintor6 rep o rted an u n u su al case of internal resorption. T he p atien t in th e ir r e p o r t h a d seven m o lars show ing radiographic evidence o f internal resorp tion. As in this case, the patient was asymp to m a tic an d d e fe rre d in itial tre a tm e n t. B eca u se o f th e e x te n t o f th e in te r n a l reso rp tio n , the tre a tm e n t plan in clu d ed later extraction of several teeth. I n te r n a l re s o rp tio n may be ra p id o r progress at a slow rate. It is imperative that the p ulp tissue be removed when the p ro cess is first diagnosed. Prom pt endodontic tr e a tm e n t is im p e ra tiv e in all cases o f internal resorption.7 T he treatm ent m ethod reported in this p aper is an alternative m eans of conserva tively treating teeth th at have large areas o f dam age from in tern al resorption, and in which n eith er the resorption n o r caries has com prom ised the dentinal sup p o rt of the cusps. It is believed that in those indi-
C L I N I C A L
T E C H N I Q U E S
Fig 6 ■ M axillary rig h t first m o la r a fte r p la c e
Fig 7 ■ M axillary rig h t first m o la r w ith co m p leted
Fig 8 ■ O ne-year follow -up show ing th e to o th
m e n t o f glass io n o m e r lining c em en t with am al
final restorations.
restored to fo rm a n d function.
gam filings a n d a glass in o m e r lining c em en t to m ask th e d ark color o f th e am algam filings.
vidual cases in w hich th e reso rp tio n has n e a rly p e r f o r a te d th e c e m e n to e n a m e l ju n c tio n o r fu rc a tio n are a s, th e re is a g rea ter d an g e r o f p erfo ra tio n with m ore conventional restorative techniques th an with the one used. It is n o t recom m ended th a t te e th w ith sev erely c o m p ro m is e d fu n c tio n a l cusps be re s to re d using this m ethod because of possible problem s with occlusal wear. T h e b ulk of th e in te rn al defect in th e crown was restored with a glass io n o m er c e m e n t w ith a m a lg a m filin g s to ta k e ad v a n ta g e o f th e ch e m ic a l b o n d in g o f glass io n o m er m aterials to den tin and to lim it the bulk o f com posite used to m ini mize the forces g en erated by polym eriza tio n s h r in k a g e . E ac h c a se s h o u ld b e carefully evaluated before trea tm e n t and only those teeth with sound cusps and ade quate d entinal support should be consid ered for this technique.
Conclusion T he article discusses a case in which severe dam age from internal resorption resulted in a decision to use a restorative m easure th a t was n o t the co nventional tre a tm e n t m ethod. After successful ro o t canal th e r apy, the exten t o f the internal dam age to th e to o th ru led o u t trea tm e n t with a full veneer crown an d eith er a post an d core o r pin am algam bu ild u p . It was d ecid ed that this m eth o d o f treatm en t m ight result in p e rfo ra tio n o f th e crow n o r ro o t, o r both. The decision was m ade to use glass ionom er and posterior com posite resin to re s to re a n d s tre n g th e n th e to o th . T h e te c h n iq u e u sed in th is case r e p o r t h as been successful.
------------------ J!iO A -----------------Dr. Ludington is associate professor, endodontics, an d Dr. H errin is associate professor, operative d e n
tistry, T h e University o f Texas H ealth Science Center, D ental B ranch, 6 5 1 6John Freem an Ave, H ouston, 77225. A ddress requests for reprints to Dr. H errin. 1. N om enclature com m ittee. An a n n o ta ted glossary ol term s u sed in endodontics. Chicago: A m erican Asso ciation o f Endodontists; 1984:5. 2. H e rrin HK. Use o f a p o sterior com posite resin) to restore teeth and sup p o rt enam el: re p o rt o f a case. JADA 1986;112:845-6. 3. B rannstrom M, Torstenson B, N ordenvall KJ. T he initial gap aro u n d large com posite restorations in vitro: the effect ol e tching enam el walls. J D ent Res 1984;63:681-4. 4. Rabinowitch BZ. In te rn a l resorption. O ral Surg O ral M ed O ral Pathol 1972;33:263-82. 5. W alton RE, L eonard LA. C racked tooth: an etiol ogy for “id io p ath ic” in te rn a l resorption? J E ndod 1986;12:167-9. 6. Fahad A, T ainlor JF. Idiopathic intern al resorp tion: re p o rt o f an u nusual case. C om pend C ontin Educ D ent 1985;6:288-95. 7. Chivian N. R oot resorption. In: C ohen S, B urns RC, eds. Pathways o f the pulp. 4th ed. St. Louis: Mosby; 1987:514.
T E C H N I Q U E S
Restoring a tooth with massive internal resorption to form and function: report of case H . Keith H errin, DDS; J o h n R. L udington, Jr., DDS, MSD
This case report describes an innovative restorative technique using glass ionomer and posterior composite resin materials. It was used to treat a patient with extensive internal resorption of the clinical crown of the maxil lary first molar. Although unconventional, this method successfully strengthened and restored the tooth.
he prim ary goal o f endodontics, restorative dentistry, and dentistry in general is to m aintain the den tition in a physiologically functional state fo r oral an d systemic h e a lth .1 Achieving this goal in teeth that have extensive inter nal reso rp tio n m akes e n d o d o n tic tre a t m e n t c o m p lic ate d an d resto rativ e co n siderations difficult. T h is a r tic le p r e s e n ts a r e p o r t o f a p atien t with a m axillary first m olar con ta in in g an e x te n s iv e a r e a o f in te r n a l resorption in the clinical crown. Although resorption o f this m agnitude com plicated the endodontic treatm ent, it also required an innovative restorative approach using glass io n o m e r an d p o s te rio r com posite resin materials.
T
Report of case T he patient, a 30-year-old white m ale in e x c e lle n t h e a lth , was firs t seen in July
1985. H e stated th at his m axillary righ t m olars “w ere n o t feelin g rig h t.” Radiographic evidence showed a large radioluc e n t a r e a in th e d is ta l a s p e c t o f th e anatom ic crown of the maxillary right first molar. T he p atie n t could n o t relate any traum a to the tooth except that in 1980, w hile an o ral s u rg e ry re s id e n t, h e d id slightly chip the distolingual cusp o f that tooth when he was biting on a bite force strain gauge. No carious lesions o r existing resto ra tions were detected in the rem aining den titio n . All te e th in th e m a x illa ry rig h t q u ad ran t resp o nd ed to cold in a norm al m a n n e r an d n o n e o f th e te e th in this quadrant was sensitive to percussion. Clini cal visual ex a m in a tio n o f th e m axillary
r ig h t first m o la r show ed no d e te c ta b le b rea k s in th e to o th su rface to in d ic ate caries o r a perforation associated with the large radiolucent area in the crown. A pre lim inary diagnosis o f in tern al resorption was m ade. T he patient was advised to have endodontic treatm ent, b u t he elected not to have treatm en t at that time. T h ree m o n ths later the involved tooth was again radiographed, and the tooth was still a s y m p to m a tic (F ig 1). A gain th e patient elected to forgo endodontic treat ment. In M arch 1986, a radiograph indicated th a t th e ra d io lu c e n t area was som ew hat larger; however, p erforatio n through the d e n tin , c e m e n tu m , o r e n a m e l was n o t seen (Fig 2 ). Im m e d ia te , co n serv ativ e
Fig 1 ■ P eria p ic a l ra d io g ra p h , m axillary rig h t
Fig 2 ■ Bitewing rad io g rap h showing ex ten t o f
first m olar, 3 m onths a fte r original diagnosis o f
in tern al reso rp tio n , 8 m onths a fte r original diag
internal resorption.
nosis o f internal resorption.
JADA, Vol. 121, A ugust 1990 ■ 271
C L I N I C A L
T E C H N I Q U E S
endodontic treatm en t was recom m ended. In p la n n in g tre a tm e n t for the patient, consideration was given to th e possibility o f p roducing a p erforation either on the distal aspect o f the anatom ic crown or in the furcation area. A perforation in either area would fu rth e r com plicate treatm ent. C o n s id e ra tio n o f how th e to o th w ould later be resto re d was also discussed with the patient at this time. In April, nonsurgical endodontic treat m en t was started. After the onset of infil tratio n anesthesia, the tooth was isolated w ith a r u b b e r d am . A ccess to the p u lp c h a m b e r a n d re s o rb e d a re a was d o n e . Tissue was rem o v ed fro m each of these
Fig 3 ■ P h o tom icrograph o f pulp tissue showing in fla m m a tio n a n d fo c a l h e m o r r h a g e (H & E) stain, orig m ag x 50).
F ig
4 ■
P h o to m ic r o g r a p h
fro m
a re a
of
re s p o rtio n show ing g ran u latio n tissu e with focal h em orrhag e (H & E) stain, o rig mag x 50).
Fig 5 ■ P e ria p ic a l ra d io g ra p h , m ax illary rig h t first m olar, showing co m p leted endodontic treat m ent.
272 ■ JADA, Vol. 121, A ugust 1990
areas and subm itted for histologic exami nation (Fig 3, 4). H em o rrh ag e from the distal an d palatal aspect o f the reso rb ed area o f the crown was difficult to control. C alciu m h y d ro x id e p o w d e r (P u lp d e n t C o r p o r a tio n o f A m e ric a ) U .S.P. was p a c k e d in to th e p u lp c h a m b e r a n d resorbed area to aid in hem o rrh ag e con tr o l. A n IRM te m p o r a r y r e s to r a tio n (C a u lk /D e n ts p ly ) was p la c e d a n d th e reappointm en t for 1 week later was made. T he p a tie n t rem a in ed asym ptom atic. At the second ap p o in tm e n t, the tem p o rary restoration was rem oved u n d e r a ru b b er dam . T h e rem a in in g calcium hydroxide was re m o v e d fro m th e p u lp c h a m b e r, resorbed areas, and canals. T h ere was no h e m o r r h a g e . T h e p u lp c h a m b e r a n d resorbed area were inspected for signs of perforation. N one was found. T he instru m entation was com pleted. T he canals were then obturated with gutta-percha an d zinc oxide-eugenol sealer (Fig 5). T he patient rem ained asymptomatic. Two w eek s a f te r c o m p le tio n o f th e e n d o d o n t ic tr e a tm e n t, th e to o th was resto re d with use o f an innovative tech n iq u e A p o s t a n d c o r e o r a m a lg a m buildup, using pins, was elim in ated as a treatm ent option because o f the proximity of the resorbed areas to the distal cemento e n am e l ju n c tio n a n d to th e fu rc atio n area at the floor o f the pulp chamber. The resorption had o ccurred prim arily in the d istal a n d ap ica l h a lf o f th e a n a to m ic crown. W ith the exception of the conser vative endod o n tic access preparation, the o cclusal su rface o f th e to o th re m a in e d intact. T here was am ple dentin support for all cusps. R e je ctin g a full v e n e e r crow n, again b e c a u s e o f th e clo se p ro x im ity o f th e r e s o r p tio n to th e d istal su rfa c e o f th e tooth, a decision was m ade to restore the tooth with posterior com posite resin and glass io n o m e r lin in g ce m e n t co n tain in g am algam filings. T h e tem p o rary resto ra tio n was r e m o v e d a n d th e p u lp ch a m b e r/re so rb e d area carefully cleaned with a large diam eter ro u n d bur. All inte r io r aspects o f th e to o th w ere carefully inspected T he dentinal surfaces were then tre a te d fo r 20 se co n d s w ith polyacrylic acid (D urelo n liquid, P rem ier) to o p en th e d e n tin a l tu b u le s 2 a n d rem o v e th e sm ear layer. T h e pulp ch a m b e r/ resorbed are a was ap p ro x im ately tw o-thirds filled with the glass ionomer-amalgam filing mix tu re a n d allow ed to set. Because o f th e dark color o f this m aterial, it was decided to m ask it w ith a glass io n o m e r lu tin g cem ent before final restoration with a pos terior com posite m aterial (Fig 6) After the
lining cem ent was set, the enam el cavosurfaces were beveled and etched. T he tooth was th en filled increm entally to minimize any forces on the tooth generated by poly m e riz a tio n sh rin k a g e .3 A fter all excess com posite was removed from the cavosurfaces, the cavosurfaces were re-etched and flow ed w ith c lea r a u to -c u re d se ala n t to m inim ize any en am el cav o su rface/co m p o s ite d e f e c ts .2 T h e r u b b e r d a m was rem oved and the occlusion adjusted (Fig 7).
A 1-year follow-up (Fig 8) showed th a t the treatm en t m ethod chosen has restored th e to o th to fu n ctio n with only a slight d e t e r i o r a t i o n in e s th e tic a p p e a r a n c e c au sed by so m e d isc o lo ratio n from th e glass ionomer-amalgam filing cem ent used to restore the cham ber an d resorbed. Discussion From an e n d o d o n tic p o in t of view, this case p resen ts several interesting findings First, the cause o f the internal resorption is speculative. Rabinowitch4 classified inter nal re so rp tio n in p e rm a n e n t te e th in to fo u r types: id io p a th ic , p erip h e ra l, tra u matic, an d high-speed tooth preparation. T he m ost likely cause in the case rep o rted h ere is traum a. A lthough resorption as a result of traum a is generally seen in ante rior teeth, posterior teeth can also be trau m atized . W hen th e p a tie n t ch ip p e d his tooth by biting on a strain gauge, a certain am o u n t o f traum a was tran sferred to the pulp. Walton and L eonard5 proposed that a crack may in itiate in te rn al reso rp tio n , thus reinforcing the idea o f an underlying cause fo r in te rn a l reso rp tio n , nam ely a com m unication to the oral environm ent. F ahad an d T aintor6 rep o rted an u n u su al case of internal resorption. T he p atien t in th e ir r e p o r t h a d seven m o lars show ing radiographic evidence o f internal resorp tion. As in this case, the patient was asymp to m a tic an d d e fe rre d in itial tre a tm e n t. B eca u se o f th e e x te n t o f th e in te r n a l reso rp tio n , the tre a tm e n t plan in clu d ed later extraction of several teeth. I n te r n a l re s o rp tio n may be ra p id o r progress at a slow rate. It is imperative that the p ulp tissue be removed when the p ro cess is first diagnosed. Prom pt endodontic tr e a tm e n t is im p e ra tiv e in all cases o f internal resorption.7 T he treatm ent m ethod reported in this p aper is an alternative m eans of conserva tively treating teeth th at have large areas o f dam age from in tern al resorption, and in which n eith er the resorption n o r caries has com prom ised the dentinal sup p o rt of the cusps. It is believed that in those indi-
C L I N I C A L
T E C H N I Q U E S
Fig 6 ■ M axillary rig h t first m o la r a fte r p la c e
Fig 7 ■ M axillary rig h t first m o la r w ith co m p leted
Fig 8 ■ O ne-year follow -up show ing th e to o th
m e n t o f glass io n o m e r lining c em en t with am al
final restorations.
restored to fo rm a n d function.
gam filings a n d a glass in o m e r lining c em en t to m ask th e d ark color o f th e am algam filings.
vidual cases in w hich th e reso rp tio n has n e a rly p e r f o r a te d th e c e m e n to e n a m e l ju n c tio n o r fu rc a tio n are a s, th e re is a g rea ter d an g e r o f p erfo ra tio n with m ore conventional restorative techniques th an with the one used. It is n o t recom m ended th a t te e th w ith sev erely c o m p ro m is e d fu n c tio n a l cusps be re s to re d using this m ethod because of possible problem s with occlusal wear. T h e b ulk of th e in te rn al defect in th e crown was restored with a glass io n o m er c e m e n t w ith a m a lg a m filin g s to ta k e ad v a n ta g e o f th e ch e m ic a l b o n d in g o f glass io n o m er m aterials to den tin and to lim it the bulk o f com posite used to m ini mize the forces g en erated by polym eriza tio n s h r in k a g e . E ac h c a se s h o u ld b e carefully evaluated before trea tm e n t and only those teeth with sound cusps and ade quate d entinal support should be consid ered for this technique.
Conclusion T he article discusses a case in which severe dam age from internal resorption resulted in a decision to use a restorative m easure th a t was n o t the co nventional tre a tm e n t m ethod. After successful ro o t canal th e r apy, the exten t o f the internal dam age to th e to o th ru led o u t trea tm e n t with a full veneer crown an d eith er a post an d core o r pin am algam bu ild u p . It was d ecid ed that this m eth o d o f treatm en t m ight result in p e rfo ra tio n o f th e crow n o r ro o t, o r both. The decision was m ade to use glass ionom er and posterior com posite resin to re s to re a n d s tre n g th e n th e to o th . T h e te c h n iq u e u sed in th is case r e p o r t h as been successful.
------------------ J!iO A -----------------Dr. Ludington is associate professor, endodontics, an d Dr. H errin is associate professor, operative d e n
tistry, T h e University o f Texas H ealth Science Center, D ental B ranch, 6 5 1 6John Freem an Ave, H ouston, 77225. A ddress requests for reprints to Dr. H errin. 1. N om enclature com m ittee. An a n n o ta ted glossary ol term s u sed in endodontics. Chicago: A m erican Asso ciation o f Endodontists; 1984:5. 2. H e rrin HK. Use o f a p o sterior com posite resin) to restore teeth and sup p o rt enam el: re p o rt o f a case. JADA 1986;112:845-6. 3. B rannstrom M, Torstenson B, N ordenvall KJ. T he initial gap aro u n d large com posite restorations in vitro: the effect ol e tching enam el walls. J D ent Res 1984;63:681-4. 4. Rabinowitch BZ. In te rn a l resorption. O ral Surg O ral M ed O ral Pathol 1972;33:263-82. 5. W alton RE, L eonard LA. C racked tooth: an etiol ogy for “id io p ath ic” in te rn a l resorption? J E ndod 1986;12:167-9. 6. Fahad A, T ainlor JF. Idiopathic intern al resorp tion: re p o rt o f an u nusual case. C om pend C ontin Educ D ent 1985;6:288-95. 7. Chivian N. R oot resorption. In: C ohen S, B urns RC, eds. Pathways o f the pulp. 4th ed. St. Louis: Mosby; 1987:514.