Non-destructive evaluation of an internal adaptation of resin composite restoration with swept-source optical coherence tomography and micro-CT

Abstract

Swept-sourceopticalcoherencetomography(SS-OCT) andmicro-CTcan be usefulnon-destructivemethods for evaluatinginternaladaptation. There is no comparative study evaluating the two methods in the assessment ofinternaladaptationincompositerestoration. The purpose of this study was to compareinternaladaptationmeasurements of SS-OCT andmicro-CT. Two cylindrical cavities were created on the labial surface of twelve bovine incisors. The 24 cavities were randomly assigned to four groups of dentin adhesives: (1) three-step etch-and-rinse adhesive, (2) two-step etch-and-rinse adhesive, (3) two-step self-etch adhesive, and (4) one-step self-etch adhesive. After application, the cavities were filled withresincomposite. All restorations underwent a thermocycling challenge, and then, eight SS-OCT images were taken using a Santec OCT-2000™ (Santec Co., Komaki, Japan). Theinternaladaptationwas also evaluated usingmicro-CT(Skyscan, Aartselaar, Belgium). The image analysis was used to calculate the percentage of defective spot (%DS) and compare the results. The groups were compared using one-way ANOVA with Duncan analysis at the 95% significance level. The SS-OCT andmicro-CTmeasurements were compared with a paired t-test, and the relationship was analyzed using a Pearson correlation test at the 95% significance level. The %DS results showed that Group 3≤Group 4<Group 1≤Group 2 on both SS-OCT andmicro-CTimages. The %DSs onmicro-CTwere lower than SS-OCT (p<0.05) and the Pearson correlation coefficient between SS-OCT andmicro-CTwas r=0.787 (p<0.05).