Stereomicroscopic Evaluation of the Impact of Three Different Restorative Techniques on Microleakage at Gingival Seat in Class II Composite Restorations

Introduction: All resin-based restorative materials shrink causing stresses pulling the adhesive away from the cavity walls leading to the formation of gaps at the interface. The gap formation further results in marginal discoloration, bacterial invasion, secondary caries, and adverse pulpal reactions. Purpose: The purpose of this in-vitro study was to evaluate the microleakage in Class-II composite restorations with gingival wall in cementum using -(i) light cure composite resin as first gingival increment, (ii) self-cure composite resin as first gingival increment, and (iii) bonded amalgam as first gingival increment. Materials and Methods: A total of 40 extracted human molars were selected and slot Class-II cavity preparations were made on both mesial and distal surfaces with gingival margins placed in cementum. The teeth were randomly divided into 5 groups of 8 teeth each. Group-I was restored by using 2 mm thick layer of a light cured composite resin as first gingival increment while remaining of restoration was completed with light-cured composite. Group-II and Group-III were restored using self-cured composite and bonded amalgam as first gingival increments respectively. Group-IV and Group-V served positive and negative controls, respectively. Restored teeth were thermocycler, subjected to dye penetration and assessed under a stereo microscope for microleakage evaluation. Results: As per the current study, the teeth restored using bonded amalgam as first gingival increment displayed the least mean microleakage scores than other experimental groups. Conclusion: Composite resin -bonded amalgam restoration technique in Class-II Composite restoration shows the least possible microleakage and best marginal seal than other techniques.