Influence of the Registration Error on the Implantation Depth with A Fully Guided Template

Abstract

Abstract Objective: To evaluate the influence of the registration error between the digital dental model and cone-beam computed tomography (CBCT) images on the implantation depth with a fully guided template. Methods: In this research, 10 isolated dentition models and 10 resin dentition models were compared, and their optical scanning data and CBCT data were imported into virtual planning software for automatic registration. Subsequently, the virtual implant position was planned, and the implant neck platform was designed to be flushed to the preset plane of the models (“bone plane”). A fully guided template was then designed and printed. Implants were placed under template guidance in vitro, and the depth deviation of the placed implant from its planned position was measured using a micrometer. Statistical analysis was performed using SPSS 23.0, and P<0.05 was considered to be statistically significant. Results: In the test group, the contour of the crown reconstructed by CBCT was larger than that of the digital scans, the occlusal surface of isolated dentition models’ CBCT was higher than that of the digital scans after the automatic registration. The contour of the crown reconstructed by CBCT in the control group was basically the same as that of the digital scans, the crown reconstructed by resin dentition models’ CBCT was basically aligned with the crown of the digital scans after automatic registration. The research showed that the postoperative implant neck platform of the two groups was higher than the preset plane (“bone plane”). The implantation depth of the postoperative implant was evaluated, the implantation depth deviation values of the isolated dentition and resin dentition groups were 0.559±0.059 and 0.183±0.019 mm, respectively, and the difference was statistically significant (P<0.05). Conclusions: Registration error leads to insufficient implantation depth under the guidance of the fully guided template. The source of registration error may be preoperative data and registration algorithm.