Guided Endodontics versus Conventional Access Cavity Preparation: A Comparative Study on Substance Loss Using 3-dimensional-printed Teeth

Introduction: The aim of this in vitro study was to compare endodontic access cavities in teeth with calcified root canals prepared with the conventional technique and a guided endodontics approach regarding the detection of root canals, substance loss, and treatment duration. Methods: Six identical sets of upper and lower jaw models were produced with 3-dimensional-printed incisors that had simulated calcified root canals. Splints for guided access preparations were fabricated based on 3-dimensional surface scans and cone-beam computed tomographic data sets. Under simulated clinical conditions, 3 operators with different levels of experience prepared access cavities on each front tooth with the conventional technique and guided endodontics (8 teeth per technique and operator). Access cavities were volumetrically assessed on postoperative cone-beam computed tomographic scans. Statistical significance was tested by examining the overlap of 95% confidence intervals (as). Results: Canal location was successful in 10 of 24 cases (41.7%) using the conventional technique and 22 of 24 cases (91.7%) with the guided approach. The mean substance loss of the conventional access and the guided access was 49.9 mm(3) (95% CI, 42.2-57.6 mm(3)) and 9.8 mm(3) (95% CI, 6.812.9 mm(3)), respectively. The treatment lasted 21.8 minutes (95% CI, 15.9-27.7 minutes) for the conventional technique and 11.3 minutes (95% CI, 6.7-15.9 minutes) for guided endodontics. The success of the guided approach was not influenced by the experience of the operator. Conclusions: Guided endodontics allows a more predictable and expeditious location and negotiation of calcified root canals with significantly less substance loss.