Accuracy of 3 calibration methods of computer-assisted dynamic navigation for implant placement: An in vitro study

Dynamic navigation for implant placement has been reported to be more accurate than freehand surgery. However, the accuracy of the calibration methods used for navigation in partially edentulous individuals with distal extensions remains unknown.The purpose of this in vitro study on dental models was to evaluate the accuracy of 3 calibration methods of dynamic navigation for implant placement in the distal extension of partially edentulous arches.Eleven standardized polyurethane mandibular models with distal extensions were prepared. The left first molar, second molar, and second premolar from each model (33 tooth sites) were randomly assigned to 1 of the 3 calibration methods: U-shaped tube embedded with radiopaque markers, anatomic tooth cusps, and bone markers with the random number table method. Preoperative and postoperative cone beam computed tomography images were obtained for deviation analyses. The primary outcomes were 3-dimensional (3D) deviation at the implant platform and apex and angular deviation. Differences among the test groups were analyzed by using a 1-way analysis of variance (ANOVA) and the least significant difference (LSD) post hoc test (α=.05).The mean ±standard deviation 3D deviations were 0.78 ±0.34, 1.86 ±0.91, and 1.44 ±0.57 mm at the implant platform and 0.79 ±0.35, 2.19 ±1.01, and 1.49 ±0.50 mm at the apex in the U-shaped tube, tooth cusp, and bone marker groups, respectively. The 3D deviations at the implant platform and apex were significantly different among the groups (P<.01). The angular deviation was 1.36 ±0.54, 2.95 ±2.07, and 2.92 ±2.45 degrees, with no significant differences among the groups (P=.092).In the dynamic navigation of implant placement in the distal extension of partially edentulous arches, the U-shaped tube calibration with radiopaque markers was more accurate than the anatomic tooth cusp or bone marker calibration.