Quality of post and core placement by final year undergraduate dental students

The success of endodontic restoration of badly compromised teeth depends on the quality of post and core placement and the extra-coronal restoration. Ensuring that students place posts to acceptable quality standards is therefore essential. The aim of this study was to radiographically evaluate post placement by final year undergraduate dental students and to identify any predictors of performance. Two hundred retrospectively and randomly selected posts placed by sixth year students were evaluated radiographically. Data on student gender; number and quality of radiographs; periapical pathology; tooth location; root canal treatment quality; amount of remaining gutta percha; gap between gutta percha and post; post-to-root width; crown-to-root ratio; and types of core material and crowns were recorded. Four criteria were used to grade post placement quality: (i) amount of remaining gutta percha; (ii) gap between gutta percha and post; (iii) post width to root ratio; and (iv) crown-to-root ratio. Assessments were scored to produce final grades. Data are presented using descriptive statistics and the chi-squared test was used to investigate whether student gender or tooth location were associated with final grade. Post and core quality was acceptable in most cases (97.5% were graded as adequate), with no differences in quality between male and female students nor according to tooth location (anterior, premolar, and molar). Just over half of radiographs were adequate quality (53.5%), while just under half were assessed as less than adequate (46.5%) due to cone cutting, overlap, shortening or elongation, although this did not affect formal assessment of post quality. General outcomes of post and core placement by undergraduate students were good, with few errors that might affect the prognosis and long-term survival of treated teeth. Providing undergraduate dental students with clear guidelines on when and how to take radiographs throughout the procedure may improve the quality of post and core treatment and reduce the risk of multiple unnecessary radiographic exposures. From the clinical perspective, although dental students generally place high quality posts and cores, it remains important to monitor the quality and performance of post placement as this determines the survival of compromised teeth.