Comparative Evaluation of Microleakage in Cavities Restored with Nanohybrid and Microfilled Composites Using Oblique Incremental Technique- An in Vitro- Study.

ABSTRACT

Many advancements have been done in the field of dentistry for resin composites applications. However, polymerization shrinkage stays a problem. Marginal gap and microleakage in between tooth cavity wall and restorative material is caused by forces of contraction, masticatory forces, polymerization shrinkage, poor adhesion, temperature variables, and inadequate moisture control. An impaired marginal seal resulting due to microleakage provides entry of oral fluids, ions, bacteria which causes recurrent caries, discoloration and hastening of marginal breakdown of restoration, hypersensitivity, pathology of pulp that would decrease the life of restoration. The purpose of restoring cavities by using nanohybrid and micro filled composite was to assess if it would eliminate or decrease microleakage in this in vitro study. We wanted to assess the effectiveness of nanohybrid and micro filled composites with regard to microleakage in class I cavity restoration.METHODSStandardized class I cavities were prepared over thirty teeth. The teeth samples were randomly distributed in to two groups based on composite used for restoration. Group A (n=15) Restored with nanohybrid composite followed by light curing. Group B (n =15) Restored with micro filled composite followed by light curing. The samples were stored in a 1% chloramine beta-hemihydrate solution for a day and then thermocycling procedure was performed. The samples were soaked in 2 % methylene blue for a day and sectioning of samples was done through the center of restoration using a diamond disk and analysed for methylene blue dye penetration with a stereomicroscope in 12X magnification. Scoring was done based on the criteria of a 0-4 scale.RESULTSChi square test was used for performing statistical analysis. No significant difference in the microleakage score between nanohybrid and micro filled composite was seen (p = 0.338).CONCLUSIONSIn this study both groups showed microleakage. However, nanohybrid composite resin showed better marginal adaptation of restoration as compared to micro filled composite resin.