Technical quality of root fillings and periapical status in root filled teeth in Jonkoping, Sweden

Aim To study changes in technical quality of root fillings and periapical status in root filled teeth in random samples of 20 to 70 year-olds between 1973 and 2003. Methodology Data from dentate subjects aged 20-70 years from examinations conducted in 1973 (n = 498), 1983 (n = 530), 1993 (n = 547) and 2003 (n = 491) were used for the analysis. Length of root fillings were measured on radiographs to the nearest 0.1 mm. Adequate seal was defined as a root filling without lateral and/or apical voids. Periapical status was assessed according to the periapical index. All observations were made by one calibrated observer registered from full mouth radiographic examinations. Teeth with root fillings ending within the canal without lateral or apical voids were considered adequate. The association between root filling quality and periapical status was analysed by means of the Chi-squared test and a multilevel logistic regression analysis. Results Adequately root filled teeth had a significantly lower frequency of apical periodontitis than inadequately root filled teeth (11.8% vs. 22.8%). The frequency of technically adequate root fillings increased statistically significant from 1973 (23.7%) to 2003 (36.4%) without a concomitant improvement of the periapical status in root filled teeth over time (24.5% vs. 24.6%). Conclusions This study reports on an improving technical quality of root fillings over time, without a concomitant improvement of the periapical status in root filled teeth. A larger proportion of treated molars over time may be of importance for the result.