The aim of the study was to compare two frequently used dental age estimation methods for accuracy. A total of 479 panoramic radiographs in age groups 6–14 years from a German population were evaluated. The dental age of 268 boys and 211 girls was assessed by means of the method of Demirjian (1973) and Cameriere (2006) and compared with their actual chronological age. Demirjan’s method showed an overestimation of dental age compared to chronological age in all age groups for boys (mean difference −0.16, p = 0.010, range −0.35 to 0.09), age group 9 showed an underestimation. Using the same method for girls (mean difference −0.18, p = 0.008, range −0.45 to 0.13), an overestimation could also be shown in all age groups except for age groups 8 and 13. Results for Cameriere’s method showed for boys (mean difference 0.07, p = 0.314, range −1.38 to 3.83) in age groups 6 to 11 an overestimation, but in age groups 12 to14 an underestimation. The results for girls (mean difference 0.08, p = 0.480, range −1.55 to 4.51) showed an overestimation for age groups from 6 to 10, and an underestimation in age groups 11 to 14. The comparison shows an advantage of Demirjian’s method for both genders. While Cameriere’s method showed a higher inaccuracy in all age groups, Demirjian’s method showed more appropriate results for dental age estimation of the investigated German population. To avoid errors in forensic age estimation and to prevent misidentifications for defendants in criminal processes, further studies of more precise methods for age estimation for the German population are required.
The detection of possible root canal perforations caused during a metal post placement is frequently difficult to diagnose. The aim of this study was to investigate the accuracy of apex locators to diagnose such perforations. Thirty mesiolingual root canals of extracted mandibular molars were instrumented (30/.04) and a post space was prepared. A root canal perforation was intentionally made at the bi-furcation (n = 15). Metal posts were cemented in 15 perforated and 15 non-perforated root canals. The teeth roots were embedded in an agar-agar solution. The resulting measurements (“short” or “beyond” the apex) disclosed if a perforation could be identified with five different apex locators (ProPex II, Elements Apex Locator, Apex NRG, Raypex 5 and Raypex 6). The sensitivity and specificity (95% interval confidence) were calculated. All devices excluded the absence of perforations (100% with 95% confidence interval [78%; 100%] specificity). The Apex NRG and Raypex 6 detected all perforations (100% with 95% confidence interval [78%; 100%] sensitivity). The ProPex II, Elements Apex Locator, and Raypex 5 detected 14 out of 15 perforations (93% with 95% confidence interval [68%; 100%] sensitivity). All devices determined root canal perforations, due to metallic posts, within clinical acceptable ranges.