Composite shear bond strength on the giomer to mineral trioxide aggregate MTA at different setting times

Abstract

Introducing pulp dental materials which are supported by scientific evidences have resulted in increase of alive pulp treatment in recent years. Bonding restorative and covering materials of pulp is of great importance. The aim of present investigation was to study stability of micro hybrid composite cutting bond Giomer to MTA in time intervals of (immediately after treatment, 2 hour, and three days after mixing MTA). Methodology: In this experimental study, 90 samples of MTA were prepared and classified into two groups (each group involing 45 sampes) based on type of restorative material (composite or gumer) used in. Based on evaluation time, 2 hours and 45 minutes and three hours). After bonding process, the stability of samples' cutting bond was measured using universal test machine or loading speed 0.5 mm/min at three different time levels. Data obtained from repeated measurement of ANOVA and T-test were analyzed using SPSS. 20. Findings: Finding of present study indicated that stability of composite cutting bond to MTA was low at first, but it increased significantly after 2 hours and 45 minutes (p=0.002). No significant change was observed till three days (p=0.088). Stability level of Giomer cutting bond to MTA didn't show significant change since preparation time to 2 hours and 45 minutes after preparation time (p=0.738). But such stability reached its minimum level three days after preparation (p=0.000). generally comparison of average stability of cutting bond of two materials during three days indicated that composite with average 3.56 1.15 had higher cutting stability than Giomer with average 2.481.159 (p=0.000). Conclusion: Composite cutting bond stability to MTA was significantly more than Giomer cutting stability to MTA. Stability of Giomer cutting bond to MTA, also, decreased through as time passed. This is while, composite cutting bond stability to MTA increased through time passage.