Evaluation of working length determination based on the analysis of cone-beam computed tomographic images and an electronic apex locator: a retrospective study.

Krystyna Pietrzycka, Mateusz Radwański, Halina Pawlicka



Introduction: The root canal length determination is a significant outcome predictor for endodontic treatment. The aim of this retrospective, clinical study was to evaluate the accuracy of working length (WL) determination in preexisting cone-beam computed tomography (CBCT) images and compare them with the data of clinical working length determination by using an electronic apex locator (EAL) in treated teeth, recorded in the patients’ cards. 

Methods: The analysis of medical records of 35 patients who underwent root canal treatment (RCT) by an endodontist in a dental practice in Lodz, Poland was performed. The data of the working length of the treated tooth recorded in the patient's card, control RVG image after final obturation and CBCT scan before RCT were evaluated. The Shapiro-Wilk normality test and tStudent test were used in statistical analysis. The significance level was set up at p<0.05. 

Results: There were no statistically significant differences between compared groups in terms of WL determination with EAL than CBCT (p>0.05). In the case of medical diagnosis (pulpitis vs gangrene) and treatment (primary vs retreatment) the obtained results were also statistically insignificant (p>0.05). 

Conclusions: This retrospective, clinical study showed that CBCT scans can be successfully used for endodontic working length determination. Future investigations are needed to evaluate whether preexisting CBCT scans may replace initial periapical radiographs.


electronic apex locator, cone-beam computed tomography, root canal treatment, working length determination

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DOI: https://doi.org/10.21164/pomjlifesci.685

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