Influence of light curing mode on degree of conversion, and marginal and internal adaptation of Class II Bulk Fill resin restoration

Abstract

The objective of this study is to evaluate the effectiveness of different modes of light curing, analyzing the influence of irradiance on the degree of conversion and formation of internal and external gaps in Class II restorations using Bulk fill resin composites and resin used by incremental technique. Eighty bovine incisors will be cut and worn to simulate posterior teeth, which will be made class II preparations. The specimens will be divided into four groups according to the restorative material used: Tetric N-Ceram (Ivoclar Vivadent), GrandioSO (VOCO), Tetric N-Ceram Bulk Fill (Ivoclar Vivadent), Admira fusion X tra (VOCO). The Bulk fill resins will be inserted in a single increment of 4 mm and in the remaining groups will be used oblique incremental technique. The curing light unit used will be Bluephase N (Ivoclar Vivadent) in two modes (high intensity and soft start). The degree of conversion is estimated by infrared Fourier transform. (FTIR) (Spectrum One, PerkinElmer, Beaconsfield, UK), with the ATR accessory. For the assessment of external and internal gap the specimens will be evaluated in stereomicroscope (Discovery V20, Zeiss, Gottingen, Germany) using a magnification of 100x. The results will be statistically analyzed and discussed against the relevant literature. (AU)