Comparison of the Effect of Dentin Bonding, Dentin Sealing Agents on the Microleakage of Provisional Crowns Fabricated with Direct and Indirect Technique-An Invitro Study

摘要

Background: Postoperative sensitivity after temporization is acommon complaint in Fixed Partial Denture patients. It is causedby weak and ill fitting temporary restorations which resultsin microleakage. This can be controlled by providing goodtemporary restorations and by coating the exposed dentinaltubules of the prepared tooth with dentin bonding agent ordental varnish.Aim: The purpose of the study was to determine the effect ofdentin-bonding, dentin sealing agents on the microleakage oftemporary crowns made by tooth colored auto polymerizingresin fabricated with direct and indirect technique.Materials and Methods: Thirty premolar and molar human teethwere collected which were extracted recently was used for thestudy. The teeth were marked and divided into 3 groups eachcontaining 10 nos. They were individually mounted with selfcure acrylic resin. It was then mounted on a milling machine andcrown preparations done. Temporary crowns were fabricatedby direct and indirect method with two types of materials. Ingroup A (Control group), the temporary crowns fabricated withboth direct and indirect method were cemented directly withtemporary luting cement. In group B dentine-bonding agent(solobond M) was applied once to the prepared surface of eachtooth specimen before the cementation of temporary crownswhere as in case of group C a single layer of dental varnish isapplied prior to crown cementation. The entire specimens wereimmersed in 1% methylene blue and allowed to undergo thermaltreatment. It was then sectioned in a hard tissue microtome.Each section was evaluated for dye penetration into the dentintubules by comparing it with a visual scale.Statistical Analysis: SPSS Version 13 software was used fornon-parametric data analysis by a qualified statistician. P-valuesless than 0.05 (p-value<0.05) were considered to be statisticallysignificant.Results: Group B (Dentin Bonding Agent) specimens cementedwith crowns fabricated in direct technique showed the leastamount of microleakage when compared with group A and groupC. Group C (Dental Varnish) specimen showed comparativelymore amount of microleakage than that of group B. Group A(control group) specimens showed the maximum amount ofmicroleakage.Conclusion: The application of a single layer of Dental varnishappears to be of no significant benefit when compared to crownscemented with the application of Dentin bonding agent on thetooth surface. The application of a single layer of Dentin bondingagent (Solobond M) and temporary crowns fabricated with directtechnique may be of some benefit for crown preparations as aninterim measure prior to the luting of final crown.