In vivo assessment of accuracy of Propex II, Root ZX II, and radiographic measurements for location of the major foramen

OBJECTIVES: The aim of this in vivo study was to assess the accuracy of 2 third-generation electronic apex locators (EALs), Propex II (Dentsply Maillefer) and Root ZX II (J. Morita), and radiographic technique for locating the major foramen (MF). MATERIALS AND METHODS: Thirty-two premolars with single canals that required extraction were included. Following anesthesia, access, and initial canal preparation with size 10 and 15 K-flex files and SX and S1 rotary ProTaper files, the canals were irrigated with 2.5% sodium hypochlorite. The length of the root canal was verified 3 times for each tooth using the 2 apex locators and once using the radiographic technique. Teeth were extracted and the actual WL was determined using size 15 K-files under a × 25 magnification. The Biostat 4.0 program (AnalystSoft Inc.) was used for comparing the direct measurements with those obtained using radiographic technique and the apex locators. Pearson's correlation analysis and analysis of variance (ANOVA) were used for statistical analyses. RESULTS: The measurements obtained using the visual method exhibited the strongest correlation with Root ZX II (r = 0.94), followed by Propex II (r = 0.90) and Ingle's technique (r = 0.81; p < 0.001). Descriptive statistics using ANOVA (Tukey's post hoc test) revealed significant differences between the radiographic measurements and both EALs measurements (p < 0.05). CONCLUSIONS: Both EALs presented similar accuracy that was higher than that of the radiographic measurements obtained with Ingle's technique. Our results suggest that the use of these EALs for MF location is more accurate than the use of radiographic measurements.

Light-emitting diode assessment of dentinal defects: the role of presumed extraction forces

OBJECTIVES: The evaluation of iatrogenic dentinal defects in extracted teeth may be influenced by extraction forces and prolonged dry times. The purpose of this study was to compare the presence of dentinal defects in freshly extracted, periodontally compromised teeth with those in a group of teeth with uncontrolled extraction forces and storage time. MATERIALS AND METHODS: The experimental group consisted of eighteen roots obtained from teeth extracted due to periodontal reasons with class II or III mobility. They were kept in saline and sectioned within 1 hour following extraction. The control group consisted of matched root types obtained from an anonymous tooth collection, consistent with previous dentinal defect studies. The slices were obtained at 3, 6, and 9 mm from the apex. The imaging process exposed all specimens to no more than 60 seconds of dry time. The × 12.8 magnification was used for the 9 mm slices and × 19.2 magnification for the 3 mm and 6 mm slices under light-emitting diode (LED) transillumination. The root canal spaces and periodontal tissues were masked to minimize extraneous factors that might influence the evaluators. Chi-square test was used for statistical analysis. RESULTS: Dentinal defects were detected in 17% of the experimental group teeth, compared to 61% of control teeth (p = 0.015). CONCLUSIONS: LED transillumination assessment of freshly extracted roots with class II or III mobility showed smaller number of dentinal defects than roots with uncontrolled storage time and extraction forces. The use of freshly extracted roots with mobility should be considered for future dental defect assessment studies.