Radiographic caries diagnosis by clinicians in Norway and Western Australia

In connection with continuing education courses in Norway and Western Australia (WA), dealing with caries diagnosis and treatment decisions, pre-tests were conducted. The pre-tests involved 433 dentists in Norway (ND), and 62 dentists (WAD) and 108 dental therapists (WAT) in WA, altogether 603 clinicians. Radiographs of 68 approximal surfaces were to be diagnosed and a treatment proposal was requested for each surface. ND showed the best overall diagnostic quality measured by the area beneath ROC-curve (P < 0.00001). The frequency of false-positive diagnoses (over-registrations) on sound surfaces varied between 7.1% (ND) and 11.9% (WAT) while the frequency of true-positive scores for lesions in the outer half of dentine varied from 57.4% (ND) to 48.1% (WAT). The mean numbers of restorations suggested by the three groups of clinicians were: ND: 14.3; WAD: 13.0; and WAT: 14.5. None of the differences was statistically significant. The proportion of sound surfaces proposed filled varied considerably between the groups, from 4.3% among Norwegian dentists to 10.6% among WAT (P < 0.0001). Of the lesions penetrating the outer half of dentine, the ND group would have restored 34.5% and the Australian clinicians somewhat fewer: WAD 25.6% and WAT 26.5%. The 11.3% of the ND who proposed more than two fillings on sound surfaces were responsible for 51.2% of the total number of filling proposals on sound surfaces. The corresponding numbers in the Australian group were 19.4% (WAD) and 33.3% (WAT) who made 73.6% and 75.7% of the restorative proposals on sound surfaces respectively.(ABSTRACT TRUNCATED AT 250 WORDS)