Evaluating health gains from restorative dental treatment

A simulation of the caries process over time in posterior approximal tooth surfaces was modelled and tentative evaluations made of health gain from restorative treatment under two sets of assumed conditions. Using published data, the decision model allowed the influence of three variables to be reflected in sensitivity analysis, 1. caries progression, 2. diagnostic accuracy, 3. survival time of fillings. Progress of 50 hypothetical initially sound surfaces, 40 with enamel, and 10 with dentine lesions, was followed over two notional, successive 5-yr time periods. A surface could terminate as sound, enamel lesion, dentine caries, filled, refilled, refilled twice or extracted. Utility values were applied to the end state frequencies to evaluate health gain (from 0 to 100). Under a set of conditions A, diagnostic accuracy reflected that of current general practice and 50% of fillings survived up to 5 yr. Under a set B, diagnostic accuracy was that of a trained epidemiologist and 50% of fillings survived up to 10 yr. Assumption A scored 75.3 while B scored 81.9, suggesting scope for added health gain through improvement of practice standards.