Total-etch versus self-etch adhesive: Effect on postoperative sensitivity

Abstract

Self-etching adhesives are believed to prevent postoperative sensitivity when used under posterior resin-based composite restorations. The authors tested a twofold hypothesis: a self-etch, or SE, adhesive would result in less postoperative sensitivity than a total-etch, or TE, adhesive; an SE adhesive would result in poorer enamel marginal integrity than a TE adhesive. Patients were selected on the basis of requiring Class I and II restorations in molars and premolars. The authors placed 30 restorations with the SE material (Clearfil SE Bond, Kuraray America, New York) and 36 restorations with Prime & Bond NT (Dentsply Caulk, Milford, Del.), which uses 34 percent phosphoric acid to etch enamel and dentin simultaneously. Preparations were of standard design, with all margins in enamel without beveling. Upon rubber dam isolation, the authors conditioned the enamel and dentin walls with the self-etching primer (for Clearfil SE Bond) or etched with the proprietary 34 percent phosphoric acid (for Prime & Bond NT), followed by application of the corresponding dentin adhesive. Teeth were restored with the proprietary hybrid resin-based composite indicated for posterior restorations: Clearfil AP-X for Clearfil SE Bond or Esthet-X Micro Matrix Restorative for Prime & Bond NT. The restored teeth were evaluated preoperatively and at two weeks, eight weeks and six months postoperatively for sensitivity to cold (ice), air and masticatory forces, as well as for marginal discoloration. Analysis of variance revealed no statistically significant differences in postoperative sensitivity between the SE and TE materials at any recall time. Marginal discoloration was rated as "absent" for all restorations at six months. Only one tooth displayed sensitivity to occlusal forces at six months. The SE adhesive did not differ from the TE adhesive in regard to sensitivity and marginal discoloration. Postoperative sensitivity may depend on the restorative technique rather than on the type of dentin adhesive used.