Trends in Teaching Posterior Restorations in North American Dental Schools: A Comparative Study.

Objectives: To compare trends in teaching and placement of composite resin versus amalgam in posterior restorations in Canadian dental schools with those in the United States.

Methods: Secondary descriptive and statistical analyses were performed on data from 2 previous studies. The data consisted of responses to questionnaires on teaching policies and the proportion of posterior restorations (amalgam and composite resin) performed in Canadian and US dental schools. Fisher's exact test and 2-sample z-test were used to compare the proportions.

Results: Canadian dental schools allocated less time than US schools to teaching composite resin restorations (p = 0.006): 22.2% of Canadian schools versus 76.4% of US schools devoted more than 50% of preclinical teaching time to such restorations. Canadian dental schools also dedicated more time to teaching amalgam restorations (p = 0.041): 33.3% of Canadian schools versus 8.8% of US schools devoted 50-75% of preclinical teaching time to amalgam restorations. Between 2008 and 2018, a significantly higher proportion of composite resin restorations were performed in US dental schools than in Canadian schools (p < 0.001).

Conclusions: In Canadian dental schools, teaching of posterior composite resin restorations was more conservative than in US schools. There was no consensus among Canadian and US dental schools on composite resin preparation techniques or contraindications. Clear, standardized guidelines pertaining to composite resin teaching policies are suggested.