Comparison of patient sensitivity using dentin bonding agent versus zinc phosphate base beneath the amalgam restorations: An in vivo comparative study

Aim: The aim of the present study is to evaluate and compare patient sensitivity following the amalgam restorations using two different materials beneath them - zinc phosphate base and dentin bonding agent. Materials and Methods: Thirty individuals aged between 20 years and 60 years were selected who presented with two class I carious lesions located in different quadrants. Both the teeth were filled at the same appointment. Following rubber dam isolation, conventional cavities were prepared for the amalgam restorations. One tooth received zinc phosphate base while the other received dentin bonding agent beneath the amalgam restoration. High copper non-γ2 amalgam was triturated using amalgamator by condensing it into the cavity. Questionnaires were given to the patients for recording sensitivity scores to heat, cold, or biting at the end of 1, 3, 7, and 14 days. Results: Significance was determined based on the P values obtained from the simple curve z-test. On day 1, when groups I and II were compared, no significant difference in number of patients reporting postoperative sensitivity was found. On day 3, more number of patients reported sensitivity with zinc phosphate cement compared to those with dentin bonding agent. On day 7, there was great reduction in sensitivity in both groups compared to day 1 and day 3 but comparatively more in teeth with zinc phosphate base. On day 14, there was no significant sensitivity in both groups, patients showing no sensitivity to both zinc phosphate base and dentin bonding agent. Conclusion: Postoperative sensitivity was relatively more in teeth restored with zinc phosphate base compared to that restored with dentin bonding agent. Postoperative sensitivity resolved earlier in restorations with dentin bonding agent compared to zinc phosphate base, and sensitivity resolved with time in both the restorations