Methods: Retrospective analysis of data of seven patients with oral and maxillofacial tumors who underwent surgery between January 2019 and January 2021 using a combination of mixed reality and surgical navigation. Virtual surgical planning and navigation plan were based on preoperative CT datasets. Through IGT-Link port, mixed reality workstation was synchronized with surgical navigation, and surgical planning data were transferred to the mixed reality workstation. Osteotomy lines were marked with the aid of both surgical navigation and mixed reality images visualized through HoloLens. Frozen section examination was used to ensure negative surgical margins. Postoperative CT datasets were obtained 1 week after the surgery, and chromatographic analysis of virtual osteotomies and actual osteotomies was carried out. Patients received standard oncological postoperative follow-up.

Results: Of the seven patients, four had maxillary tumors and three had mandibular tumors. There were total of 13 osteotomy planes. Mean deviation between the planned osteotomy plane and the actual osteotomy plane was 1.68 ± 0.92 mm; the maximum deviation was 3.46 mm. Chromatographic analysis showed error of ≤3 mm for 80.16% of the points. Mean deviations of maxillary and mandibular osteotomy lines were approximate (1.60 ± 0.93 mm vs. 1.86 ± 0.93 mm). While five patients had benign tumors, two had malignant tumors. Mean deviations of osteotomy lines was comparable between patients with benign and malignant tumors (1.48 ± 0.74 mm vs. 2.18 ± 0.77 mm). Intraoperative frozen pathology confirmed negative resection margins in all cases. No tumor recurrence or complications occurred during mean follow-up of 15.7 months (range, 6-26 months).

CASE SUMMARY: We reported a case of sclerosing odontogenic carcinoma of the maxilla in a 62-year-old woman, who presented with an indolent right palatal swelling, which progressively increased in size over 7 years. Right subtotal maxillectomy with surgical margins of approximately 1.5 cm was performed. The patient remained disease free for 4 years following the ablation surgery. Diagnostic workups, treatment, and therapeutic outcomes were discussed.

OBJECTIVE: The aim of this study was to evaluate the clinical effects and accuracy of three-dimensionally (3D)-printed patient-specific surgical plates used for mandibular defect reconstruction.

METHODS: This study included patients who underwent mandibular defect reconstruction with vascularized autogenous bone grafts between January 2012 and August 2021. They were divided into experimental (fixation with 3D-printed surgical plates) and control (fixation with conventional surgical plates) groups. Flap survival rate, postoperative complications and patient self-evaluated facial appearance were compared. Mandibular reconstruction accuracy evaluation included postoperative position deviation of the whole mandible, transplanted bone graft, lower mandibular border, mandibular condyle, and mandibular angle on the reconstructed side compared to baseline.

RESULTS: This study included 20 patients (14 males, six females; age, 39.45 ± 11.69 years), ten each in the experimental and control groups. The mean follow-up was 16 ± 22.05 (range, 6-99) months. All procedures were successful, no plate-related complications (breakage, loosening, or exposure of the surgical plates) were reported, and all patients were satisfied. The groups were statistically similar in th e position deviation of the whole mandible, transplanted bone graft, mandibular condyle, and mandibular angle, but the position and morphology of the lower mandibular border on the reconstructed side in the experimental group were better than those in the control group (P = 0.016).