Prevalence of Different Types of Crown Restorations after Root Canal Treatment of Posterior Teeth in Kerman, Iran

Background & Aims: Crown restoration of teeth after root canal treatment protects their remaining structure against breakage and infection of the root canal, and will replace the missing structure. This study was performed to identify the prevalence of different types of crown restorations after root canal treatment of posterior teeth in Kerman, Iran, in 2013. Methods: This cross-sectional study was carried out on 410 individuals (1047 endodontically treated teeth) in 3 radiology centers in Kerman. To collect data, the existence of an endodontically treated posterior tooth was evaluated through panoramic radiography, and patients’ demographic information (including sex, age, education level, and their dentist’s education level) were obtained. The endodontically treated posterior teeth were not entered into this study if they did not have suitable restorations, had lost the tooth crown due to extensive caries, were not preservable, or were bridge abatements. Crown restorations were recorded based on their types, crown, amalgam, and composite with or without cusp coverage, and being a molar or premolar tooth. Data were analyzed in SPSS software using chi-square test. All P-values of less than 0.05 were considered significant. Results: In the present study, 203 (49.5%) men and 207 (50.5%) women participated. The mean age of subjects was 36.84 ± 9.76 years. Among the 1047 studied teeth, 380 (36.3%) were premolar teeth and 667 (63.7%) were molar teeth, and 316 teeth (30.20%) had a full crown. There was a statistically significant difference between existence of crown treatment, and educational level and age of patients. Amalgam and composite restoration had a statistically significant difference in terms of patients’ sex; amalgam restoration was more common in men, while composite restorations were more common in women. Crown treatment was more common in the specialists group, while amalgam restoration without cusp coverage was more common in the general dentists group. Conclusion: The results showed that amalgam or composite crown restorations without cusp coverage are common, which illustrates the necessity of emphasizing the importance of crown restorations in long term survival of root treated teeth in dentistry colleges.