A
R
T
I
C
L
E
S
Enamel surface “dysmineralization” can be defined as a disturbance in formation of the inorganic component of enamel during amelogenesis. Enamel microabrasion, a method of removing certain enamel dysmineralization and décalcification coloration defects, is described. In many cases, with insignificant and unrecognizable loss of enamel, superficial enamel discoloration defects can be permanently eliminated, improving the appearance of treated teeth.
Enamel microabrasion for removal of superficial dysmineralization and décalcification defects T heodore P. C roll, DDS
n a m e l su rfa c e “ d y s m in e r a liz a tio n ” can be defined as a d istu r bance in fo rm atio n of the in o r g a n ic c o m p o n e n t o f e n a m e l d u r in g am elogenesis. Such ab n o rm a l m in e ra l ization of the m a tu rin g enam el surface can result in brow n spots, w hite enam el opacities, or m ulticolored tooth surface d efects w h ic h ca n be u n s ig h tly . T h e a u th o r has co in ed the term d y sm in e r alization because of inadequacies inherent in th e term s h y p o p la s ia a n d hy p o calcification w hen describing enam el surface c o lo ra tio n defects. A lth o u g h th e cause of enam el dysm in eralizatio n can som e tim es be determ ined, for exam ple in cases of w hite or brow n stain from fluorosis, u s u a lly th e cau se o f in tr in s ic en am el surface discoloration is unknow n. An acid /abrasive co m p o u n d used for enam el surface m icroabrasion is expected on the m arket in 1990. P rem a C om pound (P re m ie r D e n ta l P ro d u c ts ) in c lu d e s ab rasiv e p a rtic le s a n d a m ild c o n c e n tratio n of hydrochloric acid in a waters o lu b le g el-p a ste . W h en a p p lie d by a special m andrel on a 10:1 gear reduction h andpiece, an in sig n ific a n t a n d u n rec ognizable am o u n t of enam el is removed.
E
B ecause so m a n y d y s m in e r a liz a tio n c o lo ra tio n defects are co n fin e d to the o u te rm o s t few h u n d r e d m ic ro n s of e n a m e l, m a n y c a n be p e r m a n e n tly “ m ic ro a b ra d e d ” aw ay w ith im m ed iate im p ro v e m e n t of to o th a p p e a ra n c e . In a d d itio n , c e rta in w h ite d é c alcific atio n enam el lesions caused by ch ro n ic stasis of dental p la q u e can also be elim inated by enam el m icro ab rasio n . Such lesions are co m m o n ly seen after resin -b o n d ed o rthodontic brackets or cem ented bands are rem oved fro m p a tie n ts w hose o ral h y g ien e p rac tice s w ere n o t a d e q u a te .' T h e o n ly d e te r m in a n t of success for e lim in a tio n o f an e n a m e l c o lo ra tio n defect by enam el m ic ro a b ra sio n is the depth to w hich the lesion penetrates the tooth surface. T h e illu stratio n s (Fig 1-23) show the te ch n iq u e of enam el m icro ab rasio n by rotary ap p licatio n of Prem a Com pound. P atien ts w ith different types of lesions are p ic tu re d w ith lo n g -te rm resu lts of tre a tm e n t. I n a d d itio n , o n e case is describ ed in w h ic h th e en a m e l lesio n was too deep for enam el m icroabrasion correction an d a bonded com posite resin was required. O ther p h o to g rap h s show
p a tie n ts w h o b en e fited fro m a c o m b i n a tio n of e n a m e l m ic r o a b r a s io n a n d com posite resin b o nding. Discussion After m uch success u sin g an 18% hydro c h lo ric a c id - p u m ic e m ix tu r e a n d a w o o d e n stick a p p l ic a to r fo r e n a m e l m ic r o a b r a s io n c o lo r m o d if ic a tio n ,2-5 re se a rc h c o m m e n c e d o n a tr e a tm e n t m ethod w hich w o u ld be safer, quicker, an d easier. Prem a C o m p o u n d was devel oped an d p atented as a low -acid, h ighab rasiv e, w a te r-so lu b le g e l-c o m p o u n d for very slow rotary pressure ap p lica tio n .6' 7 T h e m aterial has been used successfully for m any p atien ts since 1985 an d gives eq u al enam el co lo r im p ro v em en t w hen com pared w ith the 18% hydrochloric acidp u m ic e m e th o d . T h e new c o m p o u n d is safer because it has a m uch lower acid c o n te n t, a n d b e c a u s e o f its p a s te lik e consistency, it does n o t flow u n co n tro l lably. In ad d itio n , the rotary ap p licatio n m ethod takes less clinical tim e com pared to n o n p o w e re d fin g e r p re ssu re a p p l i cation. In the past 4 years, certain general principles ab o u t enam el m icroabrasion JADA, Vol. 120, April 1990 ■ 411
ARTICLES
Fig 1 ■ A 31-year-old woman had white “snowcapping” enamel dysmineralization.
Fig 2 ■ After placement of the rubber dam and se a lin g the dam -enam el m arg in w ith copal varnish, Prem a C om pound was applied w ith a hard synthetic rubber prototype mandrel.
Fig 3 ■ A h a n d a p p lic a to r can be used to concentrate pressure in local regions. Such hand applicators will be available when the compound is marketed.
F ig 4 ■ T h e w h ite defect on the left in ciso r was elim inated after about 5 m inutes of inter m ittent application of the com pound. Treatm ent of the rig h t incisor was then started w ith the 10:1 gear reduction handpiece.
Fig 5 ■ After both white defects were removed, treated surfaces were p olished w ith fine flu oridated prophylaxis paste, and neutral sodium fluoride-gel was applied and left in place for 4 minutes.
Fig 6 ■ T he teeth are shown immediately after the enam el microabrasion procedure was com pleted. Compare with Figure 1.
Fig 7 ■ T h is 8-m onth postoperative view reveals m inute traces of white coloration that were not discernible at conversation distance. (Figures 1-7 show the same patient.)
Fig 8 ■ A 17-year-old girl had unsightly brown enamel discoloration.
Fig 9 ■ Enam el m icroabrasion was performed as described in Figures 1-6, using a prototype m andrel and 10:1 gear red u ctio n han d p iece. The teeth are shown 6 m onths postoperatively. (Figures 8 and 9 show the same patient.)
have em erged: —T h ere is no know n risk to the dental p u lp from enam el m icroabrasion treat m ent. As originally described in a report ab o u t enam el m icroabrasion using co n c e n tr a te d h y d r o c h lo r ic a c id ,3 P re m a C o m p o u n d , w ith m ild acid c o n c en tra tio n , d oes n o t p e n e tr a te e n a m e l to endanger the dentin o r p u lp w hen used as described in this article. —S u cce ssfu l re s u lts are p e rm a n e n t. U n lik e tooth bleaching, discolored enam 412 ■ JADA, Vol. 120, April 1990
el is removed, n o t merely altered.4 6 8 —F or cases in w h ich it is u n ce rtain h o w deep ly en am el d y sm in e ra liz a tio n s ta in p e n e tra te s th e su rfa ce , e n a m e l m ic r o a b r a s io n s h o u ld be a tte m p te d . R outine com posite resin bo n d in g proce d u re s c a n be p e rfo rm e d s u b s e q u e n tly if d is c o lo ra tio n c a n n o t be su fficie n tly im proved by m icroabrasion (Fig 17-19). In addition, enam el m icroabrasion may result in p artial correction of tooth color an d deeper stains can be corrected w ith
c o m p o s ite re s in b o n d in g (F ig 15, 16, 20 - 22 ).
— E n am el m ic ro a b ra sio n s h o u ld n o t be a tte m p te d fo r p a tie n ts w ith to o th discoloration from d entinal discoloration su c h as w ith te tra c y c lin e s ta in in g o r d e n tin o g e n e s is im p e rfe c ta (F ig 23). E nam el m icroabrasion is only successful for superficial enam el stain. O ther color correction m ethods or dental restorations w hich m ask the d en tin sh o u ld be con sidered for teeth w ith deep in trin sic
ARTICLES
Fig 10 ■ A 9-year-old boy had m u ltico lo red enam el d y sm in eralizatio n th a t ap p eared to penetrate too deeply for successful microabrasion co rre ctio n . T re a tm e n t w as attem p ted before placem en t of bonded co m p o site resin veneer restorations.
F ig 11 ■ An 11-m o n th p o sto p e rativ e in cisa l view show s accep tab le la b io lin g u a l enam el thickness.
Fig 13 ■ A 16-year-old girl had m ultiple décal c ific a tio n defects asso ciated w ith p o o r o ral hygiene practices during orthodontic treatment.
Fig 1 4 l One m onth after enamel microabrasion, enam el c o lo ra tio n w as greatly im proved. A lth o u g h there was some in fla m m a tio n , the g in g iv al co n d itio n had im proved because of better oral hygiene practices. (Figures 13 and 14 show the same patient.)
F ig 15 ■ A teenage g irl h ad extensive w h ite décalcification caused by plaq u e stasis d u rin g orthodontic treatm ent. T he arrows identify small carious lesions, which necessitated sm all com posite resin restorations.
Fig 16 ■ All areas of décalcification were much im proved by enam el m icro ab rasio n , an d the sm all cario u s lesio n s resto red w ith bonded polishable visible light polymerized composite resin .1 T h is 6-m onth po sto p erative view also shows im proved gingival conditions. (Figures 15 and 16 show the same patient.)
Fig 17 ■ It was expected that this white lesion on this 30-year-old wom an’s tooth was too deep for correction by microabrasion.
Fig 18 ■ After unsuccessful m icroabrasion, tooth preparation showed that the discolored enamel penetrated to the dentinoenamel junction.
discoloration. —M o st b ro w n e n a m e l d y s m in e r a li zation defects are superficial enough to be easily rem oved w ith enam el m ic ro abrasion. —O n ly 50% to 75% of w h ite enam el defects are su fficie n tly su p e rfic ial th a t they can be removed w ith enam el micro-
abrasion. As a d en tist g ains experience w ith the technique, it w ill become more ap p a re n t w h ich lesions can be success fu lly tre a te d . H o w ev er, so m e tim e s a practitioner can n o t be sure of the depth of a c o lo ra tio n defect. In su c h cases, it is w o rth a tte m p tin g m ic ro a b ra s io n initially, after advising the p atien t or
F ig 12 ■ E nam el m icroabrasion rem oved the discolored su rface layer and the p a tie n t had sm ooth lustrous enamel surfaces 11 m onths after treatment. (Figure 10-12 show the same patient.)
p a re n ts th a t c o m p o site re sin b o n d in g m ig h t be required. It is p ru d en t to give all p atien ts a slig h tly pessim istic p ro g nosis for success of enam el m icroabrasion. In th at way, there is less d isa p p o in tm en t if treatm en t fails an d successful results are especially ap p reciated . “ Before an d a f te r ” c o lo r p h o to g r a p h s of en a m e l
Croll : MICROABRASION FOR REMOVAL OF DYSMINERALIZATION ■ 413
ARTICLES
Fig 19 ■ T h e restored rig h t central incisor is show n immediately after composite resin bonding procedures were com pleted. (Figures 17-19 are the same patient.)
m icroabrasion cases an d bond in g results are esp ecially h e lp fu l w hen d iscussing color correction procedures w ith patients. — T re a te d te e th s h o u ld be assessed w h ile w et w ith saliva. D ry teeth show enam el discoloration defects more vividly th a n d o w et te e th , a n d te e th w h en observed outside of the dental office are usually moist. — E n a m e l m ic r o a b r a s io n does n o t re n d e r a to o th su rfa ce m o re p ro n e to d en tal caries. O n the contrary, enam el su rfa ce q u a lity of m ic ro a b ra d e d te eth predictably im proves as tim e passes after tr e a tm e n t. A s h in y g la s s lik e su rfa ce texture is form ed o n treated teeth w ith in a few m onths after treatm ent. T h e exact m ech an ism of this p h en o m en o n is not k n o w n , b u t the a u th o r believes a p p li c a tio n of th e a c id /a b ra siv e c o m p o u n d gives en am el surfaces a su p e rfin e p o l is h in g , u n lik e o th e r d e n ta l p o lis h in g agents. Subsequently, as m icroabraded
Fig 22 ■ T hree years after enamel microabrasion for b o th ce n tra l in c iso rs an d a p p lic a tio n of bonded com posite resin on the left tooth, the teeth h ad a n attractiv e appearance (com pare w ith F ig u re 20). (Figures 20-22 are the same patient.)
414 ■ JADA, Vol. 120, April 1990
Fig 20 ■ T his teenage boy had idiopathic brown and white enamel dysmineralization defects.
enam el rem ineralizes, the to o th surface som ehow re-forms w ith a sm ooth luster resem bling a highly polished m icrofilled com posite resin. It has also been observed th a t m ic ro a b ra d e d en a m e l surfaces do n o t seem to accu m u late d en tal p la q u e as rea d ily as u n tre a te d a d ja c e n t teeth. If th a t is a g en e ral o ccu rren ce, a o n e tim e m ic ro ab rasio n p o lis h in g o f o th e r a x ia l e n a m e l r e g io n s w h ic h te n d to accum ulate p la q u e m ig h t be w orthw hile. In vivo research is needed to investigate the nature a n d im plications of all lo n g term enam el surface changes after enam el m icroabrasion w ith P rem a C om pound. —M echan ical rem o v al o f su p e rfic ial enam el defects u sin g burs, abrasive stones, or disks does n o t give the sam e results as en am el m ic ro a b ra sio n u s in g P rem a C o m p o u n d . N o m a tte r h o w c a re fu lly m echanical enam el “ s tr ip p in g ” is p e r form ed, identifiable m arks in the enam el surface can usually be seen. Also, favor-
F ig 23 ■ D eep in trin s ic to o th d isc o lo ra tio n cannot be improved with enamel microabrasion. Dentinal discoloration caused by dentinogenesis imperfecta or tetracycline stain (shown in this photograph) cannot be im proved w ith enamel microabrasion.
Fig 21 ■ E nam el m icro ab rasio n pro v ed suc cessful for m ost of the discoloration, b u t the bright w hite lesion on the left central incisor remained. T he white defect was cut away with a w ater-cooled rotary d iam ond bu r, and the to o th w as p rep ared for a bonded p o lish a b le com posite resin. T he lesion alm ost completely penetrated the enamel layer.
able surface texture changes caused by rem ineralization p henom ena do n ot occur after m echanical enam el rem oval, in the sam e m a n n e r as w ith m ic ro a b ra s io n . In ad d itio n , chem ical reactions may occur o n the enam el surface as the hydrochloric ac id c o m p o n e n t of P rem a m ixes w ith w ater a n d enam el breakdow n products. S u ch r e a c tio n s c o u ld co n c e iv a b ly be b e n e f ic ia l to r e s u lt a n t e n a m e l c o lo r, su rface te x tu re, an d o p tic a l p ro p ertie s of the enam el. —E n am el m ic ro ab rasio n sh o u ld n o t be c o n fu se d w ith to o th “ b le a c h in g .” B leaching has n o effect on w hite super fic ia l e n a m e l d is c o lo r a tio n , a n d it is p erfo rm ed u sin g co n c en tra ted o x y g en a tin g a g e n ts su c h as 35% h y d ro g e n p e ro x id e . E n a m e l m ic ro a b ra s io n im proves tooth color by removal of super ficial discolored, dysm ineralized enamel. —T h e p re c ise a m o u n t o f e n a m e l elim in a te d by enam el m icro ab rasio n is u n im p o r ta n t, as lo n g as a s u ffic ie n t th ic k n e s s o f e n a m e l re m a in s fo r p r o te c tio n of u n d e rly in g to o th stru c tu re , for overall strength of the tooth d u rin g f u n c tio n , a n d for ac ce p ta b le co sm etic appearance. A scan n in g electron m icro scope an a ly sis has sh o w n th a t enam el m icroabrasion of the approxim ate force a n d d u ra tio n used for color correction tr e a tm e n t, a p p lie d to th e su rfa ce s of h u m a n teeth, resu lts in enam el loss of less th a n 200 /urn (p erso n al c o m m u n i cation, Dr. U. Jacobsson-H unt, November 1988). A d d itio n a l stu d ies are o n g o in g to fu rth e r q u an tify enam el loss d u rin g the procedure. — E n a m e l m ic ro a b ra s io n s h o u ld be p e rfo rm e d w ith a ll a v a ila b le safety m easu res. T h e d e n tist a n d a ssista n t
ARTICLES
should wear protective gloves, and the patient should be provided with eye glasses. Also, a rubber dam is essential. Although the hydrochloric acid content of Prema Compound is relatively mild, it can still damage oral soft tissues if in contact for an extended period.9 For further safety, enamel microabrasion should always be performed using a 10:1 gear reduction handpiece which reduces rpm’s so the acid/abrasive compound will not splatter during application.
ation defects can be permanently elimi nated, improving the appearance of treated teeth. -----------------------JW O A ----------------------The author acknowledges financial interest in Prema Compound by virtue of a licensing agreement with Premier Dental Products Co. The author thanks Jan Bosler for assistance with the manuscript. Publication of names of products does not imply endorsement by the American Dental Association.
Summary Enamel microabrasion, a method of removing certain enamel dysmineral ization and décalcification coloration defects is described. In many cases, with insignificant and unrecognizable loss of enamel, superficial enamel discolor
Dr. Croll is in private practice, pediatric dentistry in Doylestown, PA. He is clinical associate professor, department of pediatric dentistry, University of Pennsylvania School of Dental Medicine; and adjunct clinical professor, department of pediatric dentistry, University of Texas Health Science Center at Houston (Dental Branch). Address requests for reprints to Dr. Croll, East St and N Main St, Doylestown, PA 19801-3897.
1. Croll TP. Bonded resin sealant for smooth surface enamel defects: new concepts in “micro restorative” dentistry. Quintessence Int 1987;18:5-10. 2. Croll TP, Cavanaugh RR. Enamel color mod ification by controlled hydrochloric acid-pumice abrasion. I. technique and examples. Quintessence Int 1986;17:81-7. 3. Croll TP, Cavanaugh RR. Enamel color mod ification by controlled hydrochloric acid-pumice abrasion. II. further examples. Quintessence Int 1986;17:157-64. 4. Croll TP, Cavanaugh RR. Hydrochloric acidpumice enamel surface abrasion for color modifica tion: results after six months. Quintessence Int 1986;17:335-41. 5. Croll TP. Enamel color improvement: all things considered. Quintessence Int 1986;17:271-5. 6. Croll TP. Enamel microabrasion for removal of superficial discoloration. J Esthetic Dent 1989;1:14-20. 7. Croll TP. Enamel microabrasion: the technique. Quintessence Int 1989;20:395-400. 8. Croll TP. A case of enamel color modification: 60 year results. Quintessence Int 1987;18:493-5. 9. Croll TP, Killian CM, Miller AS. Effect of Prema Compound on human gingiva: report of a case. Quintessence Int (In press).
Croll : MICROABRASION FOR REMOVAL OF DYSMINERALIZATION ■ 415
R
T
I
C
L
E
S
Enamel surface “dysmineralization” can be defined as a disturbance in formation of the inorganic component of enamel during amelogenesis. Enamel microabrasion, a method of removing certain enamel dysmineralization and décalcification coloration defects, is described. In many cases, with insignificant and unrecognizable loss of enamel, superficial enamel discoloration defects can be permanently eliminated, improving the appearance of treated teeth.
Enamel microabrasion for removal of superficial dysmineralization and décalcification defects T heodore P. C roll, DDS
n a m e l su rfa c e “ d y s m in e r a liz a tio n ” can be defined as a d istu r bance in fo rm atio n of the in o r g a n ic c o m p o n e n t o f e n a m e l d u r in g am elogenesis. Such ab n o rm a l m in e ra l ization of the m a tu rin g enam el surface can result in brow n spots, w hite enam el opacities, or m ulticolored tooth surface d efects w h ic h ca n be u n s ig h tly . T h e a u th o r has co in ed the term d y sm in e r alization because of inadequacies inherent in th e term s h y p o p la s ia a n d hy p o calcification w hen describing enam el surface c o lo ra tio n defects. A lth o u g h th e cause of enam el dysm in eralizatio n can som e tim es be determ ined, for exam ple in cases of w hite or brow n stain from fluorosis, u s u a lly th e cau se o f in tr in s ic en am el surface discoloration is unknow n. An acid /abrasive co m p o u n d used for enam el surface m icroabrasion is expected on the m arket in 1990. P rem a C om pound (P re m ie r D e n ta l P ro d u c ts ) in c lu d e s ab rasiv e p a rtic le s a n d a m ild c o n c e n tratio n of hydrochloric acid in a waters o lu b le g el-p a ste . W h en a p p lie d by a special m andrel on a 10:1 gear reduction h andpiece, an in sig n ific a n t a n d u n rec ognizable am o u n t of enam el is removed.
E
B ecause so m a n y d y s m in e r a liz a tio n c o lo ra tio n defects are co n fin e d to the o u te rm o s t few h u n d r e d m ic ro n s of e n a m e l, m a n y c a n be p e r m a n e n tly “ m ic ro a b ra d e d ” aw ay w ith im m ed iate im p ro v e m e n t of to o th a p p e a ra n c e . In a d d itio n , c e rta in w h ite d é c alcific atio n enam el lesions caused by ch ro n ic stasis of dental p la q u e can also be elim inated by enam el m icro ab rasio n . Such lesions are co m m o n ly seen after resin -b o n d ed o rthodontic brackets or cem ented bands are rem oved fro m p a tie n ts w hose o ral h y g ien e p rac tice s w ere n o t a d e q u a te .' T h e o n ly d e te r m in a n t of success for e lim in a tio n o f an e n a m e l c o lo ra tio n defect by enam el m ic ro a b ra sio n is the depth to w hich the lesion penetrates the tooth surface. T h e illu stratio n s (Fig 1-23) show the te ch n iq u e of enam el m icro ab rasio n by rotary ap p licatio n of Prem a Com pound. P atien ts w ith different types of lesions are p ic tu re d w ith lo n g -te rm resu lts of tre a tm e n t. I n a d d itio n , o n e case is describ ed in w h ic h th e en a m e l lesio n was too deep for enam el m icroabrasion correction an d a bonded com posite resin was required. O ther p h o to g rap h s show
p a tie n ts w h o b en e fited fro m a c o m b i n a tio n of e n a m e l m ic r o a b r a s io n a n d com posite resin b o nding. Discussion After m uch success u sin g an 18% hydro c h lo ric a c id - p u m ic e m ix tu r e a n d a w o o d e n stick a p p l ic a to r fo r e n a m e l m ic r o a b r a s io n c o lo r m o d if ic a tio n ,2-5 re se a rc h c o m m e n c e d o n a tr e a tm e n t m ethod w hich w o u ld be safer, quicker, an d easier. Prem a C o m p o u n d was devel oped an d p atented as a low -acid, h ighab rasiv e, w a te r-so lu b le g e l-c o m p o u n d for very slow rotary pressure ap p lica tio n .6' 7 T h e m aterial has been used successfully for m any p atien ts since 1985 an d gives eq u al enam el co lo r im p ro v em en t w hen com pared w ith the 18% hydrochloric acidp u m ic e m e th o d . T h e new c o m p o u n d is safer because it has a m uch lower acid c o n te n t, a n d b e c a u s e o f its p a s te lik e consistency, it does n o t flow u n co n tro l lably. In ad d itio n , the rotary ap p licatio n m ethod takes less clinical tim e com pared to n o n p o w e re d fin g e r p re ssu re a p p l i cation. In the past 4 years, certain general principles ab o u t enam el m icroabrasion JADA, Vol. 120, April 1990 ■ 411
ARTICLES
Fig 1 ■ A 31-year-old woman had white “snowcapping” enamel dysmineralization.
Fig 2 ■ After placement of the rubber dam and se a lin g the dam -enam el m arg in w ith copal varnish, Prem a C om pound was applied w ith a hard synthetic rubber prototype mandrel.
Fig 3 ■ A h a n d a p p lic a to r can be used to concentrate pressure in local regions. Such hand applicators will be available when the compound is marketed.
F ig 4 ■ T h e w h ite defect on the left in ciso r was elim inated after about 5 m inutes of inter m ittent application of the com pound. Treatm ent of the rig h t incisor was then started w ith the 10:1 gear reduction handpiece.
Fig 5 ■ After both white defects were removed, treated surfaces were p olished w ith fine flu oridated prophylaxis paste, and neutral sodium fluoride-gel was applied and left in place for 4 minutes.
Fig 6 ■ T he teeth are shown immediately after the enam el microabrasion procedure was com pleted. Compare with Figure 1.
Fig 7 ■ T h is 8-m onth postoperative view reveals m inute traces of white coloration that were not discernible at conversation distance. (Figures 1-7 show the same patient.)
Fig 8 ■ A 17-year-old girl had unsightly brown enamel discoloration.
Fig 9 ■ Enam el m icroabrasion was performed as described in Figures 1-6, using a prototype m andrel and 10:1 gear red u ctio n han d p iece. The teeth are shown 6 m onths postoperatively. (Figures 8 and 9 show the same patient.)
have em erged: —T h ere is no know n risk to the dental p u lp from enam el m icroabrasion treat m ent. As originally described in a report ab o u t enam el m icroabrasion using co n c e n tr a te d h y d r o c h lo r ic a c id ,3 P re m a C o m p o u n d , w ith m ild acid c o n c en tra tio n , d oes n o t p e n e tr a te e n a m e l to endanger the dentin o r p u lp w hen used as described in this article. —S u cce ssfu l re s u lts are p e rm a n e n t. U n lik e tooth bleaching, discolored enam 412 ■ JADA, Vol. 120, April 1990
el is removed, n o t merely altered.4 6 8 —F or cases in w h ich it is u n ce rtain h o w deep ly en am el d y sm in e ra liz a tio n s ta in p e n e tra te s th e su rfa ce , e n a m e l m ic r o a b r a s io n s h o u ld be a tte m p te d . R outine com posite resin bo n d in g proce d u re s c a n be p e rfo rm e d s u b s e q u e n tly if d is c o lo ra tio n c a n n o t be su fficie n tly im proved by m icroabrasion (Fig 17-19). In addition, enam el m icroabrasion may result in p artial correction of tooth color an d deeper stains can be corrected w ith
c o m p o s ite re s in b o n d in g (F ig 15, 16, 20 - 22 ).
— E n am el m ic ro a b ra sio n s h o u ld n o t be a tte m p te d fo r p a tie n ts w ith to o th discoloration from d entinal discoloration su c h as w ith te tra c y c lin e s ta in in g o r d e n tin o g e n e s is im p e rfe c ta (F ig 23). E nam el m icroabrasion is only successful for superficial enam el stain. O ther color correction m ethods or dental restorations w hich m ask the d en tin sh o u ld be con sidered for teeth w ith deep in trin sic
ARTICLES
Fig 10 ■ A 9-year-old boy had m u ltico lo red enam el d y sm in eralizatio n th a t ap p eared to penetrate too deeply for successful microabrasion co rre ctio n . T re a tm e n t w as attem p ted before placem en t of bonded co m p o site resin veneer restorations.
F ig 11 ■ An 11-m o n th p o sto p e rativ e in cisa l view show s accep tab le la b io lin g u a l enam el thickness.
Fig 13 ■ A 16-year-old girl had m ultiple décal c ific a tio n defects asso ciated w ith p o o r o ral hygiene practices during orthodontic treatment.
Fig 1 4 l One m onth after enamel microabrasion, enam el c o lo ra tio n w as greatly im proved. A lth o u g h there was some in fla m m a tio n , the g in g iv al co n d itio n had im proved because of better oral hygiene practices. (Figures 13 and 14 show the same patient.)
F ig 15 ■ A teenage g irl h ad extensive w h ite décalcification caused by plaq u e stasis d u rin g orthodontic treatm ent. T he arrows identify small carious lesions, which necessitated sm all com posite resin restorations.
Fig 16 ■ All areas of décalcification were much im proved by enam el m icro ab rasio n , an d the sm all cario u s lesio n s resto red w ith bonded polishable visible light polymerized composite resin .1 T h is 6-m onth po sto p erative view also shows im proved gingival conditions. (Figures 15 and 16 show the same patient.)
Fig 17 ■ It was expected that this white lesion on this 30-year-old wom an’s tooth was too deep for correction by microabrasion.
Fig 18 ■ After unsuccessful m icroabrasion, tooth preparation showed that the discolored enamel penetrated to the dentinoenamel junction.
discoloration. —M o st b ro w n e n a m e l d y s m in e r a li zation defects are superficial enough to be easily rem oved w ith enam el m ic ro abrasion. —O n ly 50% to 75% of w h ite enam el defects are su fficie n tly su p e rfic ial th a t they can be removed w ith enam el micro-
abrasion. As a d en tist g ains experience w ith the technique, it w ill become more ap p a re n t w h ich lesions can be success fu lly tre a te d . H o w ev er, so m e tim e s a practitioner can n o t be sure of the depth of a c o lo ra tio n defect. In su c h cases, it is w o rth a tte m p tin g m ic ro a b ra s io n initially, after advising the p atien t or
F ig 12 ■ E nam el m icroabrasion rem oved the discolored su rface layer and the p a tie n t had sm ooth lustrous enamel surfaces 11 m onths after treatment. (Figure 10-12 show the same patient.)
p a re n ts th a t c o m p o site re sin b o n d in g m ig h t be required. It is p ru d en t to give all p atien ts a slig h tly pessim istic p ro g nosis for success of enam el m icroabrasion. In th at way, there is less d isa p p o in tm en t if treatm en t fails an d successful results are especially ap p reciated . “ Before an d a f te r ” c o lo r p h o to g r a p h s of en a m e l
Croll : MICROABRASION FOR REMOVAL OF DYSMINERALIZATION ■ 413
ARTICLES
Fig 19 ■ T h e restored rig h t central incisor is show n immediately after composite resin bonding procedures were com pleted. (Figures 17-19 are the same patient.)
m icroabrasion cases an d bond in g results are esp ecially h e lp fu l w hen d iscussing color correction procedures w ith patients. — T re a te d te e th s h o u ld be assessed w h ile w et w ith saliva. D ry teeth show enam el discoloration defects more vividly th a n d o w et te e th , a n d te e th w h en observed outside of the dental office are usually moist. — E n a m e l m ic r o a b r a s io n does n o t re n d e r a to o th su rfa ce m o re p ro n e to d en tal caries. O n the contrary, enam el su rfa ce q u a lity of m ic ro a b ra d e d te eth predictably im proves as tim e passes after tr e a tm e n t. A s h in y g la s s lik e su rfa ce texture is form ed o n treated teeth w ith in a few m onths after treatm ent. T h e exact m ech an ism of this p h en o m en o n is not k n o w n , b u t the a u th o r believes a p p li c a tio n of th e a c id /a b ra siv e c o m p o u n d gives en am el surfaces a su p e rfin e p o l is h in g , u n lik e o th e r d e n ta l p o lis h in g agents. Subsequently, as m icroabraded
Fig 22 ■ T hree years after enamel microabrasion for b o th ce n tra l in c iso rs an d a p p lic a tio n of bonded com posite resin on the left tooth, the teeth h ad a n attractiv e appearance (com pare w ith F ig u re 20). (Figures 20-22 are the same patient.)
414 ■ JADA, Vol. 120, April 1990
Fig 20 ■ T his teenage boy had idiopathic brown and white enamel dysmineralization defects.
enam el rem ineralizes, the to o th surface som ehow re-forms w ith a sm ooth luster resem bling a highly polished m icrofilled com posite resin. It has also been observed th a t m ic ro a b ra d e d en a m e l surfaces do n o t seem to accu m u late d en tal p la q u e as rea d ily as u n tre a te d a d ja c e n t teeth. If th a t is a g en e ral o ccu rren ce, a o n e tim e m ic ro ab rasio n p o lis h in g o f o th e r a x ia l e n a m e l r e g io n s w h ic h te n d to accum ulate p la q u e m ig h t be w orthw hile. In vivo research is needed to investigate the nature a n d im plications of all lo n g term enam el surface changes after enam el m icroabrasion w ith P rem a C om pound. —M echan ical rem o v al o f su p e rfic ial enam el defects u sin g burs, abrasive stones, or disks does n o t give the sam e results as en am el m ic ro a b ra sio n u s in g P rem a C o m p o u n d . N o m a tte r h o w c a re fu lly m echanical enam el “ s tr ip p in g ” is p e r form ed, identifiable m arks in the enam el surface can usually be seen. Also, favor-
F ig 23 ■ D eep in trin s ic to o th d isc o lo ra tio n cannot be improved with enamel microabrasion. Dentinal discoloration caused by dentinogenesis imperfecta or tetracycline stain (shown in this photograph) cannot be im proved w ith enamel microabrasion.
Fig 21 ■ E nam el m icro ab rasio n pro v ed suc cessful for m ost of the discoloration, b u t the bright w hite lesion on the left central incisor remained. T he white defect was cut away with a w ater-cooled rotary d iam ond bu r, and the to o th w as p rep ared for a bonded p o lish a b le com posite resin. T he lesion alm ost completely penetrated the enamel layer.
able surface texture changes caused by rem ineralization p henom ena do n ot occur after m echanical enam el rem oval, in the sam e m a n n e r as w ith m ic ro a b ra s io n . In ad d itio n , chem ical reactions may occur o n the enam el surface as the hydrochloric ac id c o m p o n e n t of P rem a m ixes w ith w ater a n d enam el breakdow n products. S u ch r e a c tio n s c o u ld co n c e iv a b ly be b e n e f ic ia l to r e s u lt a n t e n a m e l c o lo r, su rface te x tu re, an d o p tic a l p ro p ertie s of the enam el. —E n am el m ic ro ab rasio n sh o u ld n o t be c o n fu se d w ith to o th “ b le a c h in g .” B leaching has n o effect on w hite super fic ia l e n a m e l d is c o lo r a tio n , a n d it is p erfo rm ed u sin g co n c en tra ted o x y g en a tin g a g e n ts su c h as 35% h y d ro g e n p e ro x id e . E n a m e l m ic ro a b ra s io n im proves tooth color by removal of super ficial discolored, dysm ineralized enamel. —T h e p re c ise a m o u n t o f e n a m e l elim in a te d by enam el m icro ab rasio n is u n im p o r ta n t, as lo n g as a s u ffic ie n t th ic k n e s s o f e n a m e l re m a in s fo r p r o te c tio n of u n d e rly in g to o th stru c tu re , for overall strength of the tooth d u rin g f u n c tio n , a n d for ac ce p ta b le co sm etic appearance. A scan n in g electron m icro scope an a ly sis has sh o w n th a t enam el m icroabrasion of the approxim ate force a n d d u ra tio n used for color correction tr e a tm e n t, a p p lie d to th e su rfa ce s of h u m a n teeth, resu lts in enam el loss of less th a n 200 /urn (p erso n al c o m m u n i cation, Dr. U. Jacobsson-H unt, November 1988). A d d itio n a l stu d ies are o n g o in g to fu rth e r q u an tify enam el loss d u rin g the procedure. — E n a m e l m ic ro a b ra s io n s h o u ld be p e rfo rm e d w ith a ll a v a ila b le safety m easu res. T h e d e n tist a n d a ssista n t
ARTICLES
should wear protective gloves, and the patient should be provided with eye glasses. Also, a rubber dam is essential. Although the hydrochloric acid content of Prema Compound is relatively mild, it can still damage oral soft tissues if in contact for an extended period.9 For further safety, enamel microabrasion should always be performed using a 10:1 gear reduction handpiece which reduces rpm’s so the acid/abrasive compound will not splatter during application.
ation defects can be permanently elimi nated, improving the appearance of treated teeth. -----------------------JW O A ----------------------The author acknowledges financial interest in Prema Compound by virtue of a licensing agreement with Premier Dental Products Co. The author thanks Jan Bosler for assistance with the manuscript. Publication of names of products does not imply endorsement by the American Dental Association.
Summary Enamel microabrasion, a method of removing certain enamel dysmineral ization and décalcification coloration defects is described. In many cases, with insignificant and unrecognizable loss of enamel, superficial enamel discolor
Dr. Croll is in private practice, pediatric dentistry in Doylestown, PA. He is clinical associate professor, department of pediatric dentistry, University of Pennsylvania School of Dental Medicine; and adjunct clinical professor, department of pediatric dentistry, University of Texas Health Science Center at Houston (Dental Branch). Address requests for reprints to Dr. Croll, East St and N Main St, Doylestown, PA 19801-3897.
1. Croll TP. Bonded resin sealant for smooth surface enamel defects: new concepts in “micro restorative” dentistry. Quintessence Int 1987;18:5-10. 2. Croll TP, Cavanaugh RR. Enamel color mod ification by controlled hydrochloric acid-pumice abrasion. I. technique and examples. Quintessence Int 1986;17:81-7. 3. Croll TP, Cavanaugh RR. Enamel color mod ification by controlled hydrochloric acid-pumice abrasion. II. further examples. Quintessence Int 1986;17:157-64. 4. Croll TP, Cavanaugh RR. Hydrochloric acidpumice enamel surface abrasion for color modifica tion: results after six months. Quintessence Int 1986;17:335-41. 5. Croll TP. Enamel color improvement: all things considered. Quintessence Int 1986;17:271-5. 6. Croll TP. Enamel microabrasion for removal of superficial discoloration. J Esthetic Dent 1989;1:14-20. 7. Croll TP. Enamel microabrasion: the technique. Quintessence Int 1989;20:395-400. 8. Croll TP. A case of enamel color modification: 60 year results. Quintessence Int 1987;18:493-5. 9. Croll TP, Killian CM, Miller AS. Effect of Prema Compound on human gingiva: report of a case. Quintessence Int (In press).
Croll : MICROABRASION FOR REMOVAL OF DYSMINERALIZATION ■ 415
