Objective: To describe the effect of the ability to estimate caries depth from bitewing radiographs on restorative treatment decisions.
Methods: A 10% random sample of Dutch dental practitioners (n = 444) was sent a two-part questionnaire based on an analytic approach to radiographic caries diagnosis and restorative treatment decision making. In the second part the dentists were asked to diagnose radiographs of 105 tooth surfaces with and without dentine caries and then to make a treatment decision for each surface. A regression analysis was carried out using the negative predictive value (TN/[TN + FN]) of the restorative treatment decision for dentine caries as the dependent variable.
Results: The mean negative predictive value for the dentists' proposals from radiographs to leave surfaces untreated was 0.77 (SD 0.05; min. 0.60, max 0.87). Nine significant (P < 0.05) variables explained 65% (R2 = 0.65) of the variation in decision making. One diagnostic ability variable explained 48% of the variation found.
Conclusions: Dentists appear to take the seriousness of errors in restorative decisions into account when deciding on treatment. The ability of dental practitioners to identify and discriminate between lesions in the inner half of the enamel and the outer half of the dentine, however, plays a dominant role in their treatment decision making.