Comparative evaluation of shear bond strength of universal bonding agent and total-etch bonding agent on superficial and deep dentin

Background: To conserve the tooth structure, bonded restorations are popular nowadays. Bonding to enamel is predictable by acid-etch technique. However, bonding to dentin remains a challenge. Aim: To determine the better bonding agent between universal bonding agent and total-etch bonding agents based on shear bond strength using universal testing machine. Methodology: Eighteen human permanent mandibular molars were sectioned longitudinally to obtain thirty-six samples. Samples were randomly divided into three groups according to the bonding agent, Group A (Unbonded), Group B (Universal bonding agent) which was again divided into Subgroup B1 (Superficial dentin), Subgroup B2 (Deep dentin) and Group C (total-etch bonding agent) which was again divided into Subgroup c1 (Superficial dentin) ,Subgroup c2 (Deep dentin). Composite block was built up and samples were mounted in acrylic resin. Thermocycling was done and then samples were subjected to Universal testing machine. Statistical Analysis: The data was analysed using One-way ANOVA and Post hoc tests. Result: Universal bonding agent showed higher mean shear bond strength than total-etch bonding agent at both superficial and deep dentin level. Conclusion: The shear bond strengths of Universal Bonding agent and total-etch bonding agents were affected by the dentin level i.e., superficial and deep dentin.