A Comparative Evaluation of the Effect of Different Liners on The Microleakage in Class Ii Cavities Restored with Composite Resin – An Invitro Study

Abstract

Introcution : The marginal seal of a composite restoration has long been a challenge to the clinicians. One of the weakest links of Class II cavity preparations restored with composite resin is microleakage at the gingival margin of the proximal box. The absence of enamel at the gingival margin leads to the adhesion of composite materials to cementum / dentin, an unstable substrate.

Aim and Objective: To compare the gingival marginal microleakage in class II cavities restored with    composite resin in conjunction with different lining materials by dye penetration study using stereomicroscope.

Materials and method: Twenty freshly extracted intact human maxillary permanent molar teeth were selected for this study To simulate clinical posterior teeth alignment, the molars were mounted on stone jigs with one premolar and one molar each on the mesial and distal sides. Two standardized class II(proximal box) cavities were prepared on the mesial and distal surfaces. The dimensions of the cavities were as follows – buccolingual width 3 mm, width of gingival margin 2mm, occlusogingivally, the cavity was extended to just beyond the cementoenamel junction.

Result: There is high significant difference present in microleakage in various groups. The order of mean microleakage is

Group3>Group4>Group2>Group1

Conclusion: Glass ionomer cement, auto cure (GC IX )used as liner in class II cavities restored with composite resin showed the least microleakage among all other groups and better marginal adaptation.