Background: The current high standards in orthognathic surgery demand surgical solutions that are both ⁠ functionally ⁠ effective and aesthetically pleasing. Our approach offers one for enhanced stability, attractiveness, and nerve protection ⁠ with improved accessibility ⁠ in the majority of orthognathic scenarios ⁠ compared to an inverted L osteotomy. Methods: A case series is presented to illustrate the application and outcomes of HSSO, an optimised approach that combines the advantages of a transoral inverted L osteotomy with specific enhancements and increased versatility, ⁠ with accessibility and exposure similar to a BSSO. Results: HSSO as a completely transoral technique, demonstrate the ability to perform significant counterclockwise rotations of the mandible, eliminating the need for trocars or skin incisions. We experinced high postoperative stability when HSSO was performed in conjunction with a three-piece LeFort 1 osteotomy on a dynamic opposing arch. In comparison to an inverted L approach, we postulated that HSSO offers advantages in stability, due to the increased segmental overlap of the proximal and distal segments of the mandible. This approach is designed to enhance the safety of the inferior alveolar nerve compared to traditional sagittal split methods. Furthermore, HSSO represents an alternative to total joint replacement in select cases of idiopathic condylar resorption and is effective for correcting mandibular asymmetries while maintaining jawline aesthetics. This is achieved through the manipulation of the mandibular angle, ramus height, and inferior border without creating a step deformity in the soft tissue. Conclusions: The outcomes of HSSO highlight its capacity to deliver predictable, functional, and aesthetically pleasing results, offering a viable alternative to more traditional orthognathic techniques.

UNASSIGNED: Maxillary reconstruction is often a challenging task for the surgeons because of the complex anatomy. However, with the advances in virtual surgical planning (VSP) and 3D printing technology there is a new avenue for the surgeons which offers a suitable alternative to conventional flap-based reconstructions.
UNASSIGNED: In this article, we have described 4 case scenarios which were managed with the help of VSP and additive manufacturing technology for complex maxillary reconstruction procedures. Use of the technologies aided the clinician in achieving optimal outcomes with regards to form, function and esthetics.
UNASSIGNED: Virtual surgical planning (VSP) has gained a lot of impetus in past 1 decade. These aides the surgeon in determining the extent of disease and also carry out the treatment planning. In addition to VSP, the concept of additive manufacturing provides a viable alternative to the conventional reconstruction modalities for maxillary defect rehabilitation. Increased accuracy, rehabilitation of normal anatomical configuration, appropriate dental rehabilitation, decreased intra-operative time and post-operative complications are some of the advantages. In addition, patient-specific implants eliminate the need for a separate donor site. Apart from the treatment of pathologies, they also can be used for reconstruction of post-traumatic defect, where endosteal implant placement is not possible.
UNASSIGNED: These modalities show promising results for reconstruction of complex maxillary defects.

Augmented reality (AR) is a promising technology to enhance image guided surgery and represents the perfect bridge to combine precise virtual planning with computer-aided execution of surgical maneuvers in the operating room. In craniofacial surgical oncology, AR brings to the surgeon\'s sight a digital, three-dimensional representation of the anatomy and helps to identify tumor boundaries and optimal surgical paths. Intraoperatively, real-time AR guidance provides surgeons with accurate spatial information, ensuring accurate tumor resection and preservation of critical structures. In this paper, the authors review current evidence of AR applications in craniofacial surgery, focusing on real surgical applications, and compare existing literature with their experience during an AR and navigation guided craniofacial resection, to subsequently analyze which technological trajectories will represent the future of AR and define new perspectives of application for this revolutionizing technology.

The increasing application of virtual surgical planning (VSP) in orthognathic surgery implies a critical need for accurate prediction of facial and skeletal shapes. The craniofacial relationship in patients with dentofacial deformities is still not understood, and transformations between facial and skeletal shapes remain a challenging task due to intricate anatomical structures and nonlinear relationships between the facial soft tissue and bones. In this study, a novel bidirectional 3-dimensional (3D) deep learning framework, named P2P-ConvGC, was developed and validated based on a large-scale data set for accurate subject-specific transformations between facial and skeletal shapes. Specifically, the 2-stage point-sampling strategy was used to generate multiple nonoverlapping point subsets to represent high-resolution facial and skeletal shapes. Facial and skeletal point subsets were separately input into the prediction system to predict the corresponding skeletal and facial point subsets via the skeletal prediction subnetwork and facial prediction subnetwork. For quantitative evaluation, the accuracy was calculated with shape errors and landmark errors between the predicted skeleton or face with corresponding ground truths. The shape error was calculated by comparing the predicted point sets with the ground truths, with P2P-ConvGC outperforming existing state-of-the-art algorithms including P2P-Net, P2P-ASNL, and P2P-Conv. The total landmark errors (Euclidean distances of craniomaxillofacial landmarks) of P2P-ConvGC in the upper skull, mandible, and facial soft tissues were 1.964 ± 0.904 mm, 2.398 ± 1.174 mm, and 2.226 ± 0.774 mm, respectively. Furthermore, the clinical feasibility of the bidirectional model was validated using a clinical cohort. The result demonstrated its prediction ability with average surface deviation errors of 0.895 ± 0.175 mm for facial prediction and 0.906 ± 0.082 mm for skeletal prediction. To conclude, our proposed model achieved good performance on the subject-specific prediction of facial and skeletal shapes and showed clinical application potential in postoperative facial prediction and VSP for orthognathic surgery.

OBJECTIVE: This pilot study aims to evaluate the feasibility and effectiveness of computer-assisted surgery protocol with 3D-preformed orbital titanium mesh (3D-POTM), using presurgical virtual planning and intraoperative navigation in primary inferomedial orbital fracture reconstruction.
METHODS: Between March 2021 and March 2023, perioperative data of patients undergoing surgery for unilateral inferomedial orbital fracture treated with 3D-POTM were analyzed. Presurgical virtual planning with a Standard Triangle Language file of preformed mesh was conducted using the mirrored unaffected contralateral side as a reference, and intraoperative navigation was used. The reconstruction accuracy was determined by: correspondence between postoperative reconstruction mesh position with presurgical virtual planning and difference among the reconstructed and the unaffected orbital volume. Pre- and postoperative diplopia and enophthalmos were assessed.
RESULTS: Twenty-six patients were included. Isolated orbital floor fracture was reported in 14 (53.8%) patients, meanwhile medial wall and floor one in 12 (46.1%) cases. The mean difference between final plate position and ideal digital plan was 0.692 mm (95% CI: 0.601-0.783). The mean volume difference between reconstructed and unaffected orbit was 1.02 mL (95% CI: 0.451-1.589). Preoperative diplopia was settled out in all cases and enophthalmos in 19 (76.2%) of 21 patients.
CONCLUSIONS: The proposed protocol is an adaptable and reliable workflow for the early treatment of inferomedial orbital fractures. It enables precise preoperative planning and intraoperative procedures, mitigating pitfalls and complications, and delivering excellent reconstruction, all while maintaining reasonable costs and commitment times.

OBJECTIVE: To compare the changes in condylar position after mandibular reconstruction with free fibular flap(FFF) and the differences between computer-assisted techniques and traditional methods on CT images.
METHODS: Thirty-four patients who underwent mandibular reconstruction with free fibular flap were selected according to the inclusion and exclusion criteria. In the 3D group, virtual surgical planning (VSP) with osteotomy cutting plate and placement guiding plate were used, while the traditional group underwent freehand reconstruction. The CT data of 68 temporomandibular joints (TMJs) were recorded before and immediately after surgery. The condylar position was evaluated by measuring the anterior space (AS), posterior space (PS) and superior space (SS), and the ln (PS/AS) was calculated according to the method proposed by Pullinger and Hollender.
RESULTS: In the patients included in the 3D group, the condyle on the ipsilateral side moved slightly backward; however, in the patients in the traditional group, the ipsilateral side moved considerably anteroinferior. No obvious changes on the contralateral side were noted. In the 3D group, 33% of ipsilateral condyles were in the posterior position postoperatively when compared with the preoperative position (13%). In the traditional group, the number of ipsilateral condyles in the anterior position increased from 4 to 10, accounting for 53% postoperatively. Contrary to the traditional group, the 3D group presented less condylar displacement on the ipsilateral side postoperatively.
CONCLUSIONS: This study showed a decreased percentage of change in condylar position postoperatively when VSP was used. Virtual surgical planning improved the accuracy of FFF mandibular reconstruction and made the condylar position more stable.

UNASSIGNED: The purpose of this study was to compare the accuracy of hard tissues movements planned to result of the maxillary and mandibular positions between conventional surgical planning (CSP) and virtual surgical planning (VSP) in patients undergoing orthognathic surgery.
UNASSIGNED: A systematic electronic search was carried out in six databases and gray literature with no restriction of publication date and language. Clinical observational studies that compared accuracy of maxillary position between CSP and VSP were included. Linear measurements of the mandible in the transverse plane and linear measurements of the maxilla in the vertical, horizontal and transverse planes were considered for analysis, comparing planned to postoperative outcomes of CSP and VSP. Cochrane tool was used to assess bias risk. A meta-analysis was performed to summarize similar results by using the Review Manager 5.3 software. Significance level was set at 5%.
UNASSIGNED: Six studies (2 RCT and 4 retrospective cohorts) were included according to inclusion and eligibility criteria, involving 255 patients. The inter-rater reliability of selection and eligibility was excellent (k = 0.8315 and k = 0.9329, respectively). Two studies presented that VSP seemed to have better results than CSP regarding linear measurements of the mandible in the transverse plane. Results from CSP and VSP were similar in accuracy for hard tissue in vertical plane of maxillary position (I2 = 0%; p = 0.17), although VSP was more accurate in horizontal plane (I2 = 0%; p = 0.02).
UNASSIGNED: VSP presented better accuracy for transverse movements in mandible of asymmetric patients. VSP showed to be more accurate for movements in the horizontal plane, and qualitative analysis seemed to be more effective for transverse movements.

暂无摘要。

BACKGROUND: Tooth-supported surgical guides have demonstrated superior accuracy compared with bone-supported guides. This study aimed to modify the fabrication of tooth-supported guides for compatibility with tumor resection procedures and investigate their accuracy.
METHODS: Patients with tumors who underwent osteotomy with the assistance of modified tooth- or bone-supported surgical guides were included. Virtual surgical planning (VSP) was employed to align three dimensional (3D) models extracted from intraoperative computed tomography (CT) images. The distances and angular deviations between the actual osteotomy plane and preoperative plane were recorded. A comparative analysis of osteotomy discrepancies between tooth-supported and bone-supported guides, as well as among tooth-supported guides based on CT, cone-beam CT (CBCT), or intraoral scanner (IOS) was conducted. The factors influencing the precision of the guides were analyzed.
RESULTS: Sixty patients with 81 resection planes were included in this study. In the tooth-supported group, the mean deviations in the osteotomy plane and angle were 1.39 mm and 4.30°, respectively, whereas those of the bone-supported group were 2.16 mm and 4.95°. In the tooth-supported isotype guide groups, the mean deviations of the osteotomy plane were 1.39 mm, 1.47 mm, 1.23 mm across CT, CBCT, and IOS, respectively. The accuracy of the modified tooth-supported guides remained consistent regardless of number and position of the teeth supporting the guide and location of the osteotomy lines.
CONCLUSIONS: The findings indicate that the modified tooth-supported surgical guides demonstrated high accuracy in the maxillofacial region, contributing to a reduction in the amount of surgically detached soft tissue.

OBJECTIVE: Virtual surgical planning (VSP) has gained acceptance because of its benefits in obtaining adequate resection, achieving cephalometric accuracy, and reducing operative time. The aim of this study is to compare the rate of union between VSP and free-hand surgery (FHS), identify predictors of non-union and evaluate the difference in operative time.
METHODS: Post-operative CT were retrospectively reviewed for 123 patients who underwent maxillary or mandibular reconstruction between 2014 and 2021 using either VSP or FHS. Each apposition was graded as complete, partial or non-union. The rate of union, risk difference and inter-rater reliability were calculated. The difference in operative time was assessed. Predictors of non-union were identified using logistic regression.
RESULTS: A total of 326 appositions were graded (VSP n = 150; FHS n = 176). The rates of complete and partial union were higher with VSP than FHS (74.7% vs. 65.3%; 18% vs. 15.9%, respectively, p = 0.01). Non-union was found at a higher rate with FHS than with VSP (18.7% vs. 7.3%). The non-union risk difference was 11.4. FHS, major complications and apposition at the native bone were predictors of non-union (OR 2.9, p = 0.02; OR 3.4, p = 0.01; OR 2.5, p = 0.05, respectively). The mean surgical time was shorter with VSP than with FHS (265.3 vs. 381.5 min, p < 0.001). The inter-rater agreement was high (k = 0.85; ICC = 0.86).
CONCLUSIONS: VSP demonstrated significantly higher bony union rates and shorter operative time. FHS, development of major complications and apposition with native bone correlated with non-union.