title: Inter-operator variability in light curing.
abstract: OBJECTIVE:To test the hypothesis that operator experience influences the efficacy of light curing in a typical posterior intra-oral location. To investigate whether short cure cycles affect performance. DESIGN:A cross-sectional single-centre study designed to assess the efficacy of experienced and inexperienced operators when undertaking simulated intra-oral curing. SETTING:An in vitro laboratory based investigation conducted in a dental school during 2001. MATERIALS AND METHODS:A computer-based technique was used to monitor light intensity in a clinical simulation. Dentists and student operators were tested for their ability to cure a posterior restoration effectively. Relative light intensity was assessed against time for each operator and test run. RESULTS:Experienced (qualified) operators produced more effective and consistent cure results than less experienced undergraduate students. Operator performance was not affected by variations in irradiation time. CONCLUSIONS:This cross-sectional pilot investigation demonstrates that operator experience is a factor in successful clinical photo-curing of posterior restorations. Stable and accurate light guide positioning are required throughout the entire irradiation cycle to optimise intra-oral cure of light-activated restorations. Further investigations are planned to assess the potential of this novel method of assessment for use as a routine teaching aid in clinical practice.