Influence of flowable composite liner on the microleakage of posterior packable resin Composites - An in vitro study

Introduction: The aim of this study was to investigate the influence of flowable composite intermediary liner on the microleakage between the tooth tissue and the packable composite resin. Materials and Methods: Forty mandibular molars, each prepared with two class II cavities were randomly divided in two groups: In group A one side was restored with Solitaire (KULZER); the other side was lined with Charisma flow (KULZER) and then restored with Solitaire. In group B one side was restored with Filtek p60 (3M); the other side was lined with Filtek flow (3M) and then restored with Filtek p60. Teeth were then thermocycled for 1000 cycle at 5o and 55o and immersed in a solution of 0.5% basic fuschin dye for 24 hours. Embedded specimens were sectioned longitudinally. Cervical and occlusal microleakage was measured by the extent of dye penetration. Results: Statistically in both groups, microleakge was more in the cavities that were not lined with flowable composites and the cervical margins showed more amount of microleakage as compared to occlusal margins with and without liner. Overall there was no significant difference in the amount of leakage among the two companies at cervical and occlusal margins, with and without flowable liner. Conclusion: Microleakge was more in the cavities that were not lined with flowable composites as compared to cavities lined with flowable composite both in occlusal and cervical margins. The cervical margins showed more amount of microleakage as compared to occlusal margins with and without liner.