Clinical evaluation of amalgam bonding in class I and II restorations

Background. Many dental practitioners are bonding amalgam to tooth structure. Although in vitro studies support this procedure, its efficacy has not been adequately confirmed in the clinical environment. Methods. The authors placed traditional Class I and Class II bonded and unbonded amalgam restorations in 76 patients. Panavia 21 (J. Morita USA Inc.) was the bonding agent selected, and Aristaloy CR (Englehard Dental) and Tytin (Kerr Corp.) were the amalgam alloys used. Postoperative sensitivity and marginal fracture were evaluated at yearly intervals, for up to three years of clinical service. Results. At the patients' appointment for polishing one to two weeks after restoration placement, and at each yearly recall appointment, the authors found no significant difference in postoperative sensitivity between bonded and unbonded restorations for either amalgam alloy (x² analysis, α = .05). In addition, there was no significant difference between bonded and unbonded restorations for either amalgam alloy with respect to marginal fracture (analysis of variance and Tukey's contrasts at α = .05). Moreover, no cusp fractures were observed for either bonded or unbonded restorations. Conclusions. After three years of clinical service, amalgam bonding for traditional Class I and Class II restorations had no effect on postoperative sensitivity or marginal integrity. Clinical Implications. The merit of using adhesive bonding agents for traditional Class I and Class II amalgam restorations was not demonstrated in this three-year clinical study.