Effect of Aging on Micro-tensile Bond Strength and Color Stability of Self-adhesive Resin Composite

The objective of this study is to evaluate the micro-tensile bond strength of a newly self-adhesive resinous restorative material to dentin with and without application of universal bonding system (in-vitro) and to examine it's clinical performance by evaluation of it's color stability and marginal discoloration through a randomized clinical trial (in-vivo).

For color stability and marginal discoloration test, twenty class I cavities were prepared in the molar teeth of twenty different patients and then were randomly divided into two groups of ten patients each, where half of the molars was restored with Surefil one self-adhesive bulk-fill composite and the other half with Filtek One bulk-fill composite. A VITA Easyshade spectrophotometer was used to measure the baseline color of the restoration and at the margin after 24 hours and degree of color change and marginal discoloration after 3 months and 6 months of composite placement and then degree of color change (ΔE) was determined using the CIE L\*a\*b\* system. All discolored restored molar teeth of both composite types were polished using a series of different thickness of Sof-Lex aluminum oxide discs (coarse, medium, fine), then the degree of color change of the restoration and at the margin (ΔE) was determined and was then compared to the baseline color measurements.