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MANAGEMENT of the PRE-CAVITATION LESION SHASHI PATEL,* DDS, Msc, BDS, FAGD, FRACDS, DDPH, LDS

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MANAGEMENT of the PRE-CAVITATION LESION SHASHI PATEL,* DDS, Msc, BDS, FAGD, FRACDS, DDPH, LDS 37 MANAGEMENT OF THE PRE-CAVITATION LESION SHASHI PATEL,* DDS, MSc, BDS, FAGD, FRACDS, DDPH, LDS J--_j J..i l,S"'"')WI j>-..cl.! C � �I .:.,i ...,..__;..U 4-l>-b_, .:i'.>l:JI (..Jl:,:. o.JS'y _, .:.,�I ;.,,.._,.,.t; 0\.:.....\JI _j. .J...p ..;Li}I ..bkl-1 �j ij .:,1..;___,.\)1 � .lw .!l_;� , �_,...il E'°j °4_, \JI ..:.i4L..o)'4 ��)I_, 0\.:.....\JI _j..;r �Li_,lJ J_,�I � _r-11 �j _, • � �j JI_, ..:.il..L:::...J.1 o..U. Wli l) l'b L,. � � � .?-t...,. � �_;llC')WI r-'_;..JJ� .J��I ,j (.........,'.)t), o.:iL.JI o.:itll i-4-) "-:,il}I �1)1 r-'.?'t?' _, � , w, ..:.il.....:,o_;ll � a.l:J�I 1/\!_, � JJ J---->-j <\i� ._,.,_,....:JI�� L,.� •• y. (�Li}I �1)1 ..:.il.....:,o_;ll) � J..i, J_,i J.:....,, <$..lJ.o:11 �\JI .r--31 � � �..i..tzr-'J .:iy►-J i.J.$. cj a....,\:,:. .lw ..;_,.....:J.I ii.:iL.JI ii.:itll JL.....:....1 CJl,JJ ..,_.l:11..r.):- ,y .:,�_, cWI .tWI Preventive measures against dental caries are so successful today In certain countries and regions within countries, that the need foroperative intervention has d�creasedand the primaryresponsibility of preventing dental caries and managing early lesions has been assigned to the patient. The dentist should only intervene with restorativetreatment when specific criteria, Including some of those listed In this paper, have been satisfied. In the Interest of conservation of tooth structures, the preventive dentistryrestoration - the preventive resin restoration (PRR), (composite resin-sealant concept) or the glass lonomer/composlte resin laminate (the so called "sandwich" or "double-laminated" technique) should be considered as an alternative to traditional Class I amalgamrestorations. ThePRR or sandwich technique concept can be used when the carious lesion Is Judged to be deeper into the dentin than Is appropriate for management by fissure sealant alone, especially if no restoration exists In the tooth surface in question. The use of sealants has spawned an entirely different concept of conservation of occlusal tooth structure in the management of deep pits and fissures early In caries Involvement. The preventive dentistry restoration embodies the concepts of both prophylactic odontotomy ( enameloplasty) and extension for prevention, yet requires only a minimum or no cutting of tooth structure at the carioussite. Pain and apprehension are slight, and aestheticsand tooth conservation are minimized. Several options are available in selecting preventive dentistry restorations, depending on the professional's judgement. The first option Is to simply place a conventional sealant over the incipient lesion as well as over the remaining occlusal fissure system. The second option, advocates the use of the smallest cavitypreparation, but to remove the carious material from the bottom of a pit or fissure and then use an appropriate Instrument to place either sealant or composite. Sealant Is then placed over the polymerized material as well asflowed over the remaining fissures. Aside from protecting the fissures fromfuture caries, It also possibly protects the composite from abrasion. A third option reported Involves the use of a glass lonomer cement as the preventive glass lonomer restoration (PGIR). The glass tonomer cement is used only In the cavity preparation Involving dentin. The occlusal surface is then etched with a gel etchant, (avoiding etching the glass lonomer, If possible). The conventional resin sealant Is placed over the glass lonomer and the entire occlusal fissure system. In the event that the sealant Is lost, the fluoridecontent of the glass lonomer will help prevent future primary and �econdary caries formation. Each of these options requires a Judgement decision by the dentist. That Judgement can well be based on the criterion than If an overt lesion cannot be Jlisua/ized, It should be sealed, If It can be 'Visualized, the smallest possible preventive dentistry restoration should be used along with Its required sealant "topping.· It waspointed out that the first option could provide the preferred model for conservative treatment of Incipient and minimal, overt pit-and-fissure caries. Theseoptions would be especially valuable In areas of the world with Insufficient professional dental personnel and where preventive dentistry auxiliaries have been trained to place sealantsunder supervision. In all cases, the preventive dentistry procedure should be considered as an alternative to the traditional Class t amalgamwith Its accompanying extension for prevention that oftenIncludes the entire fissure system. Saudi Dental Journal, Vol. 12, No. 1, January- April 2000 38 PRE-c.AVITATIONMANAGEMENT Introduction or reversed Clinically, it is often difficult to recognize and diagnose the early lesion and for The pre-cavitation lesion is an area of the tooth this reason, it is important to be familiar with its where the carious process has commenced, but features from aetiological and histologic has not yet resulted in the breakdown of the standpoints. 9 enamel.1 The surface will remain smooth and New concepts in restorative dentistry concen­ the lesion cannot be detected by a probe, 2 but trate more on pr�ervingthe integrity of the tooth there is a difference in colour and translucency rather than filling a cavity. The use of materials and the lesion can be seen as a "white spot," possessing both cariostatic properties and long­ i.e., an early carious lesion3A (Fig. 1 ). Saliva has term adhesion is changing the approach to the the potential to aid remineralization particularly treatment of the early pre-cavitation lesion. 5 if it contains fluoride ions. As we are now A pre-cavitation lesion starts on the enamel moving towards an era of a more preventive surface and is due to loss of minerals from the approach, the pre-cavitation lesion can be orderly arrangement of the apatite crystals in the managed so that this early lesion can be enamel rods. The optical properties are changed, 6 arrested or reversed. Treatment requires a light is scattered, and the increasing porosity knowledge of the caries and remineralization makes the enamel less translucent. It is seen cli­ processes. It involves the commitment of the nically as a "white spot." Morphologically, altho­ dentist and the patient to surveillance and ugh the lesion has an intact surface, there is sub­ motivation. It may involve non-invasive tech­ surfacedemineralization. 10 niques or the · pre-cavitation lesion may require 7 Probably the most important fact is that the invasion, i.e., cutting a nminimal" cavity, or a surface of the enamel is relatively intact (although conventional preparation. The decision will microscopically the surface is much more porous depend on the extent of this pre-cavitation 8 than sound enamel). The implication is that the lesion, and the position of the lesion on the caries process can be r(!tarded arrested or tooth. indeed reversed before any physical cavitation requiring clinicalintervention has occurred It usually takes a period of months or even years for a carious lesion to develop. Dental caries is not simply a continual, cumulative loss of material, but rather a dynamic process, charac­ terized by alternating periods of demineraliza­ tion and remineralization.11 Demineralization is the dissolution of the calciumand phosphate ions from the hydroxyapatite crystals, which are lost into the plaque and saliva. In remineralization, calcium, phosphate and other ions in the saliva and plaque are redeposited in previously demine­ Fl�. 1. White spot enamel lesions at the cervical margins of both molar teeth. ralized areas. It is possible to have demineraliza­ tion and remineralization occurring without any From a preventive dentistry standpoint, the early loss of tooth mass. A lesion results when the identification of the pre-cavitation (incipient) cumulative, negative mineral balanceexceeds the lesion is extremely importantbecause it is during rate of remineralization over an extendedperiod 3 this stage that the carious process can be arrested The disease·can be arrested12 Received 31 December 1997; Revised 19 May1998, Address reprint requests to: 08 February1999, Accepted 12 May1999 Dr. Shashl Patel *Formerly Assistant Professor 'Shanraj Ntvas' Restorative Dental Sciences Department 22 Starmont Road, Highgate College of Dentistry, King Saud Untverslty London N6 NL Saudi Dental Journal, Vol. 12, No. 1, January-April 2000 PATEL 39 The caries process is initiated by micro-organisms ression to caries or balance of ionic exchanges which colonize the tooth surface in the formof t.ow�m:ls remineralization depends on the above dental plaque. As soonimmediate/ybegins as the plaque is removed factors.15 Whether to cut and fill the pre-cavitation from any tooth, it to build up lesion, or to manage and remineralize it, depends again. This should not be unexpected, since by on accurate diagnosis, on the position of the definition, dental plaque is composed of salivary lesion , on the/s tooththere surfacean active assessment caries, i.e., of isthe it residue, bacteria and their end products, all of pro[1ressinf1question - or · can it be arrestedP which are always present in the mouth. Thus a 8.0 goodcontinuous. plaque control programme must be It must be a daily commitment over a Glucose rinse 1 lifetime. Caries-free Both demineralization and remineralization occur 7.0 . pH /·-. --- during caries development. carious lesions 7 ./ . develop when the rate of acid-induced demine­ 6.0 ·-·_,,,.,..,.. ralization of teeth exceeds the capacity of the saliva Rampant caries to remineralize the damaged enamel com­ ·-· 5.0 ./ ponents. Following the intake of sugar, a localized 7. _,.,,...._ _,,,.,..,.. demineralization· of the enamel occurs as a result "'·---· of the acid produced by the plaque bacteria. This 4.0 negative mineral balance, if continually repeated, 0 10 20 30 40 50 60 eventually results in a carious lesion. It often inutes after glucose rinse _ryi requires months or even years, for the lesion to 13 Fi�.
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