Evaluation of bond strength of newer bonding agents to human dentin after six months of storage an analytic study

Introduction: Among various materials, composite resins have been developed in order to provide the best aesthetics to the anterior restorations as well as for posterior restorations. Resin-dentin bonds are more difficult to achieve than resin-enamel bonds, because dentin bonding relies on organic components. Materials & Methodology: A total number of 44 extracted human mandibular premolars were collected. Occlusal enamel surface was removed using an airotor and diamond bur.The collected 44 teeth were divided in to four groups according to the bonding agents used. 1st sub group with five teeth that is submitted for microtensile testing within 24 hours and SEM analysis for failure mode, 2nd sub-group contains five teeth which is submitted to microtensile bond strength after six months of storage in normal saline and thereafter for SEM analysis for failure mode, and the 3rd sub-group with one teeth which is prepared for analyzing the bond interface using SEM Results: Summarized data was presented using Tables. Data was normally distributed as tested using the Shaperio‑Wilk W test (p-value was less than 0.05). Therefore, analysis was performed using the parametric tests i.e. Independentt test (for comparing two groups) and One way Anova test (for comparing more than two groups). Level of statistical significance was set at p-value less than 0.05. Conclusion:The lowest bond strength values both at 24 hours and after 6 months in normal saline due to its solvent system (acetone, ethanol, water), which might not create a stable adhesive layer like other agents. Optimal filler load could also reduce bond strength by limiting resin availability. SEM analysis revealed that fewer resin tags, indicating incomplete penetration into dentinal tubules, resulting in weaker bonding and susceptibility to degradation. Adhesive failures indicating poor adhesion at the dentin interface, while mixed failures suggested inadequate bonding with the composite resin. This underscores the importance of refining bonding agent formulations and application techniques to ensure enduring adhesive bonds in restorative dentistry.