Purpose: We present a concept that uses the multipurpose navigation equipment of a university hospital for computed tomography (CT)-guided surgical template production, to improve the preclinical accuracy of the templates.
Materials and methods: Oral implants are planned on CT images with respect to the prosthodontic goal and anatomical considerations. Registration is performed via a modified Vogele-Bale-Hohner (VBH) mouthpiece (Medical Intelligence GmbH, Schwabmuenchen, Germany) and an external registration frame. In the laboratory, an optical navigation system is used to transfer the plan to the patient's registered dental stone cast for surgical template production. During preclinical evaluation, duplicated stone casts were drilled via the obtained surgical templates. Accuracy was evaluated by matching the preoperative CT to the CT of the drilled stone casts.
Results: Compared with present registration mouthpieces, the VBH mouthpiece requires only the dental impression of the patient's stone cast. In contrast to surgical navigation, an aiming device is used for navigated trajectory-alignment at the best technical level. There is no need for a positioning device, and the template can be immediately fabricated in a standard laboratory. The accuracy of 5 surgical templates showed a maximum normal deviation of 1.4 mm, and maximum angular deviations of 2.8 degrees .
Conclusion: The presented concept allows for successful production of CT-guided surgical templates, and may show sufficient accuracy for clinical use.