Comparative evaluation of microleakage of newer generation dentin bonding agents: An in vitro study.

Context: Adhesive dentistry has been progressing with rapid pace over the past decade. Composite resin is the most esthetic restorative material currently available for restoring teeth. In spite of it being in use since a decade, still failure cases are seen which are mainly due to polymerization shrinkage and subsequent inadequate adhesion to cavity walls, leading to microleakage. Various generations of dentin bonding agents have been introduced to overcome the shortcoming of composite resin.

Aims: To determine the microleakage of the 6 th , 7 th , and 8 th generation dentin bonding agents.

Materials And Methods: Forty-five extracted human premolars were taken for the study. Standardized Class V cavities were prepared on all the teeth. The samples were divided into three groups according to the generation of bonding agent used. Group I was bonded with the 6 th generation, Group II with the 7 th generation, and Group III with the 8 th generation dentin bonding agent. All the Class V preparations were restored with a nano-ceramic composite restorative (Ceram X). The samples were then thermocycled between 5 and 55 ± 2°C for 100 cycles and immersed in 2% methylene blue for 48 h for evaluation of microleakage under a stereomicroscope.

Statistical Analysis Used: The data was statistically analyzed using Kruskal-Wallis nonparametric analysis, and Mann-Whitney U-test was applied to compare the various groups.

Results: The microleakage value was the highest in Group II (7 th generation bonding agent) followed by Group I (6 th generation bonding agent) and least in Group III (8 th generation bonding agent).

Conclusions: The 8 th generation dentin bonding showed statistically significant results in terms of lesser microleakage as compared to the 6 th and 7 th generation dentin bonding agents.