Objectives: To elicit preferences for the outcomes of radiographic endodontic diagnosis and subsequent therapy, and to test for differences in these preferences between three types of dental specialists.
Methods: Using the "standard gamble" method, dentists involved in teaching oral diagnosis (n=26) were asked to rank on a scale of 0.0-1.0 their preferences (utilities) for four treatment outcomes, "composite filling in vital tooth", "composite restoration and root filled", "root filled and post crown" and "extraction and bridge", from a previously analysed diagnostic testing and therapeutic strategy for managing damaged anterior teeth. Respondents consisted of oral radiologists (n=9), specialized treatment planners (n=11) and specialist endodontists (n=6). Using the derived utilities, a decision analysis was subsequently carried out on the expected health value of taking periapical radiographs of patients with otherwise symptomless fractured incisors.
Results: "Composite restoration and root filled" (mean utility 0.83, SD 0.15) was the option preferred above that of "root filled and post crown" (mean utility 0.77, SD 0.16) by the entire sample of oral diagnosticians (P=0.007). Radiologists and endodontists had higher utilities for "composite restoration and root filled" than treatment planners. According to the decision analysis, for the preferred option of "composite restoration and root filled", taking a radiograph was the best strategy only when the prevalence of pathology exceeds 10%, 12% and 50% for radiologists, endodontists and treatment planners, respectively.
Conclusions: The expected utility of using radiographs as a diagnostic test varies among groups of dental specialists. We conclude that variation in utilities among dentists could in part explain variation in the diagnostic use of dental radiographs.