THE OUTCOME OF A CLINICAL-TRIAL OF A DENTIN BONDING SYSTEM - JUSTICE OR INJUSTICE

Purpose: To review the findings and to question the outcome of a clini cal evaluation of a dentin bonding system. Materials and Methods: The study was a split mouth, single blind (to patient), randomised within patient, clinical trial of Tripton used in conjunction with Opalux and the ultrafine compact-filled, experimental visible light cured resin composite M221784 (ICI Dental) in the restoration of mixed (enamel/den tin), caries free buccal-surface cervical lesions in vital, permanent canine and premolar teeth. The design of the trial was based on the th en current American Dental Association (ADA) Clinical Protocol Guideli nes for Dentin and Enamel Adhesive Materials. Restorations were placed as dictated by a predetermined randomised number scheme with each pat ient recruited to the study receiving at least one pair of matched res torations, comprising one restoration of each resin composite. Results : The study reported was discontinued at 1 year subsequent to a 17% lo ss rate between 6 and 12 months after placement, with most of the rest orations lost having been placed in what has subsequently become shown to be relatively unfavorable situations. It is suggested that the out come of clinical trials of the type considered may warrant review in t he light of new knowledge and understanding, and that regulatory bodie s setting clinical protocol guidelines must give careful consideration as to whether the criteria for this type of trial should be more rest rictive or required to include a representative range of clinically re levant situations.