Evaluation of Microleakage of Self-Adhesive Composite Resin in Pits and Fissures of Extracted Premolar Teeth: An in Vitro Study

Background and objectives: Microleakage at the interface of tooth structure and fissure sealant plays a crucial role in failure of the treatment. This in vitro study aimed to determine the microleakage of self-adhesive flowable composite resins as pit and fissure sealants. Material and Methods: 60 healthy extracted premolar teeth were randomly divided into the 4 groups (n=15), group 1) clinpro sealants (control), group 2) flowable composite resin with bonding agent (total-etch), group 3) flowable composite resin with self-etch bonding agent, and group 4) self-adhesive composite resin. After thermocycling the specimens were immersed in 2% methylene blue for 48 hours and then sectioned in the buccolingual direction. The microleakage was assessed by dye penetration using a stereomicroscope at 15X magnification. Data analysis was performed using SPSS version 18.0 as well as Mann-Whitney and Kruskal-Wallis tests. Results: There was a statistically significant difference in microleakage score between the groups (P-value = 0.006). The lowest mean of microleakage level was observed in the flowable composite group with total-etch bonding (group 2) 1.26±0.96, followed by the Clinpro sealant group (group 1) 1.62±1.20, and then the self-adhesive composite group (group 4) 1.85±1.00. Conclusion: Based on the results of this study, the microleakage of self-adhesive composite resin revealed no significant difference with conventional fissure sealant; however, the microleakage of these composite resin was higher than flowable composite resin with total-etch bonding agent.