Restorative decision making by Ontario dentists.

One-half of the dentists in general practice in Ontario were randomly selected for a survey in June 1992 to determine their practices and decision-making regarding some aspects of restorative dentistry. Using patient scenarios to describe clinical situations, respondents stated the threshold at which a restoration should be placed in various tooth surfaces of persons of different ages, according to the severity of the carious lesion and the usual restorative procedure for different case situations. A total of 1,276 (52 per cent) dentists responded to a detailed mail questionnaire. Data were entered into a personal computer (PC) and analyzed using frequencies and chi-square with the SPSS/PC+ statistical package. Multivariate analyses were undertaken to examine what characteristics of dentists independently explained variations in their usual restorative procedures for approximal and occlusal caries. With approximal lesions, as seen on bitewing radiographs, 60 per cent of the dentists indicated that they would place a restoration in a 12 year old with an enamel lesion that had not reached the dentino-enamel junction, whereas with 30- and 55-year-old patients, 28 and 20 per cent, respectively, would do so. At each patient age, there was a tendency for significantly younger dentists to restore enamel-only lesions more often than other dentists (p < .01). Variations in proposed treatment for an adult patient with above average oral hygiene, but with a small (1-1.5 mm diameter) occlusal cavity that had penetrated through the dentino-enamel junction, were also observed. In this case, 23 per cent of the dentists would prepare a conventional cavity extending to include all fissures, and restore the tooth with amalgam or composite; 45 per cent would prepare a cavity just larger than the outline of the lesion and restore it in the same way; 32 per cent would prepare a small cavity and place a preventive resin restoration. Significant differences in cavity design were also observed between graduates of the University of Toronto and the University of Western Ontario with respect to restoring approximal carious lesions. A number of the dentists' characteristics were significantly associated (p < .01) with these variations in procedures. These included the dentists' gender, year and university education and type of practice. The documentation and explanation of these large variations in restorative practices have important implications for continuing dental education.