Evaluation of Effects of Different Storage Media and Sterilization Methods on Shear Bond Strength of Composite to Enamel

Extracted teeth which contain various microorganisms are commonly used for in vitro research and may posse cross infection risk. The aim of the current study was to evaluate the effect of sterilizing storage media on shear bond strength of composite to enamel.
60 extracted human premolars without any crack or caries were included in this study. Based on storage media, time of bonding and autoclaving factors samples were divided into 6 groups: (1) Fresh teeth without autoclaving; (2) fresh teeth with autoclaving; (3) 6-months chloramine storage without autoclaving; (4) 6-months chloramine storage with autoclaving; (5) 6-months thymol storage without autoclaving; (6) 6-months thymol storage with autoclaving. Composite cylinders were bonded to the buccal surface of teeth and the shear bond strength evaluated. For each sample, type of fracture was also recorded. Data were analyzed with two-way ANOVA using SPSS version 11.5 with the level of significance set at 0.05.
Based on the shear bond strength test, storage media and autoclaving had no significant effect on bond strength (P=0.818, P=0.221 respectively). Based on the Chi-square test, type of fracture had significant association with autoclaving factor (P Type of storage media and autoclaving had no significant effect on enamel bond strength in comparison to fresh samples. However, autoclaving led to an increase in enamel cohesive fracture.