Dynamic Navigation with Real-Time Instrument Visualization for Intraoral Resection of Condylar Osteoma Using a Piezoelectric Osteotome.

The objective of this protocol is to describe a dynamic navigation technique that enables direct real-time visualization of a piezoelectric osteotome during intraoral resection of condylar osteoma. Conventional navigation workflows typically rely on a handheld probe for anatomical localization, followed by a switch to the operative instrument, which may introduce spatial error in confined intraoral surgical fields. To address this limitation, the present method integrates the piezoelectric osteotome directly into the navigation coordinate system through reverse modeling, tool calibration, and coordinate registration. This allows continuous visualization of the instrument tip and three-dimensional (3D) orientation during osteotomy without repeated probe-to-instrument transition. The protocol includes preoperative virtual surgical planning based on DICOM data, 3D modeling of the surgical instrument, intraoperative registration and calibration, navigation-guided osteotomy, and postoperative accuracy assessment. In the representative case, the operative duration was approximately 60 min, with approximately 70 mL of intraoperative blood loss and no perioperative complications. Postoperative 3D surface-deviation analysis demonstrated a mean signed deviation of -0.285 mm, a standard deviation of 0.757 mm, and a root-mean-square (RMS) deviation of 0.809 mm between the preoperative virtual surgical plan and the postoperative reconstructed model. These findings provide preliminary evidence of the technical feasibility of direct real-time navigation of the piezoelectric osteotome for transoral condylar osteoma resection.