International journal of oral and maxillofacial surgery最新文献

Accurate anatomical segmentation in computed tomography (CT) imaging is vital for diagnostics and virtual surgical planning in head and neck surgery, yet manual methods remain time-consuming and inconsistent. This study presents a dual-model artificial intelligence (AI) system that automates the segmentation of key craniofacial structures. A total of 388 clinical CT scans were processed using a two-stage nnU-Net-based approach: a coarse global model (3.0 mm resolution) followed by a fine local model (0.5 mm resolution). Ground truth segmentations of the skull, mandible, teeth, sinuses, and soft tissue were created by a single annotator and compared to the AI-based segmentation results using the Dice similarity coefficient (DSC), mean surface distance (MSD), and Hausdorff distance (HD) . High accuracy was achieved: mean DSC of 0.963 for mandible and skull, and 0.986 for soft tissue. Mean MSD values were lowest for maxillary sinus (0.134 mm) and mandible (0.150 mm). While HD remained low overall, soft tissue showed high variability (mean 25.138 mm). The AI system proved robust across varied imaging protocols, including low-resolution scans. By significantly reducing manual segmentation efforts while ensuring clinical precision, this open-access dual-model framework offers a scalable solution for diagnostic, surgical, and educational applications in craniofacial care.

The rising incidence of oral tongue cancer (OTC) among younger populations and females represents an emerging epidemiological shift for which the aetiology remains unclear. This systematic review and meta-analysis examined the epidemiological trends of OTC in female patients and aimed to identify related risk factors and exposures. Forty-nine studies were identified following PRISMA guidelines, with pooled analyses including 35,733 females and 57,821 males from 21 studies. Overall, females showed lower odds of developing OTC compared to males (odds ratio 0.51, 95% confidence interval 0.41-0.62; P < 0.001). However, females exhibited a significantly higher annual percentage change (APC) in OTC incidence when compared to males (P = 0.010), despite significantly lower rates of smoking and alcohol consumption habits (P < 0.001). This trend was particularly pronounced in developed countries compared to developing countries (P < 0.001). The younger OTC cohort showed distinct clinical features, lower human papillomavirus infection rates, and unique mutational profiles, although current data remain insufficient to form definitive conclusions. This review highlights an epidemiological shift in OTC characterized by significantly higher APC among females, particularly in developed countries and in Western nations.

In the management of the lower third molars, coronectomy has gained popularity in recent years due to its effectiveness in preventing neurosensory deficits, particularly when the tooth is in close proximity to the inferior alveolar nerve (IAN). This long-term prospective study was performed to evaluate the outcomes of patients who presented for mandibular third molar extraction and underwent coronectomy, with a minimum follow-up of 10 years. A total of 362 coronectomies performed on 277 patients (165 female, 112 male) were included. Fifty-five of the 362 coronectomy cases followed up for ≥10 years (15.2%) underwent reoperation due to exposed roots (8.0%), pain (3.9%), or infection (1.9%). Cox regression analysis showed no significant association between demographic or clinical characteristics and the need for reoperation to remove the retained roots. Kaplan-Meier analysis revealed that, at 10 years post-coronectomy, no reoperation would be required in 87.5% of cases. Notably, no nerve deficit occurred in any of the reoperation cases. The findings of this prospective study involving a large cohort and high rate of follow-up at ≥10 years after coronectomy suggest that this is a safe and efficient procedure for managing third molars in close proximity to the IAN.

In maxillofacial surgery, orbital reconstruction requires precision to address both functional and aesthetic considerations arising from both acute and elective conditions. This study presents a novel, fully automated segmentation software designed specifically for the orbital floor. This software enhances surgical planning through superior accuracy, efficiency, and usability. The authors' transdisciplinary team compiled a dataset of 1004 expert-segmented orbits from computed tomography images across multiple countries, ensuring broad anatomical representation. Developed with the nnU-Net framework, the software achieved segmentation accuracy with a mean Dice similarity coefficient of 0.935 and a mean surface distance of 0.292 mm for the orbit, and a Dice similarity coefficient of 0.917 and mean surface distance of 0.287 mm for the orbital floor-all within approximately 1 s. This performance surpasses traditional manual segmentation, which averages 25 min per orbit. The system delivered consistent results across a range of imaging sources, affirming its reliability for a wide range of clinical applications. By introducing this fully automated, high-precision tool, this study pioneers advancements in AI-driven orbital reconstructions, setting new standards for patient-specific surgical planning. Further development and integration holds the key to transforming the field, ensuring ethical compliance and enhancing informed consent.

Darwin has a very high volume of facial trauma in a largely decentralized population, providing a unique opportunity to assess mandible fracture patterns. The aim of this study was to determine whether the presence of the mandibular third molar is associated with angle fractures, and whether the absence of the third molar is associated with condyle fractures. A retrospective analysis of all patients admitted to the Royal Darwin Hospital, Australia for open reduction and internal fixation of the mandible between January 2020 and March 2024 was performed. Patients were classified by the presence/absence of the mandibular third molars and the type of mandibular fracture. The third molars were classified according to the Pell and Gregory, and Winter classifications. 475 patients suffered 792 fractures; 289 were angle fractures and 127 were condyle fractures. Angle fractures were significantly associated with the presence of mandibular third molars (odds ratio 3.31, P < 0.001), while no significance was found between the absence of third molars and condyle fractures (P = 0.076). In this study, patients with mandibular third molars were observed to have an increased risk of angle fracture, while there was no increased risk of condyle fracture in those without the third molar.

The aim of this study was to develop a machine learning classification model that can forecast salvage surgery complications. This was a retrospective analysis of all patients who underwent salvage surgery for head and neck cancer at Amrita Institute of Medical Sciences, Kochi, India. Clinical and treatment characteristics were used as predictors. Machine learning models, logistic regression, regularized logistic regression, Random Forest, and Support Vector Machine (SVM) were employed. Overall, 277 patients who underwent salvage surgery were identified, of whom 125 had complications. Random Forest gave the best test sensitivity and specificity of 80.0% (95% confidence interval 59.3-93.2%) and 71.0% (95% confidence interval 52.0-85.8%), respectively. The important features identified were reconstruction status (none), disease-free interval, type of surgery (when primary and neck surgery were combined), alcohol history, and recurrent node positivity. This study explored multiple machine-learning approaches in the predictive analysis of the morbidity of salvage surgery related to head and neck cancers. Random Forest emerged as the best classification model to predict the complications.

Precise image registration is essential for the success of image-guided craniomaxillofacial robotic surgery (IGCRS). However, current methods fail to meet the diverse needs of various craniomaxillofacial procedures. In this study, a comprehensive navigation registration strategy was developed including three techniques: removable marker (RM) registration, intraoral scan-CBCT (IOS) registration, and marker-relay (MR) registration. A phantom study was conducted using four three-dimensionally printed skulls with 20 target points each. Registration accuracy was assessed using fiducial registration error (FRE) and target registration error (TRE), with a U-shaped tube fixed marker (FM) as the control. The mean FRE for FM, RM, IOS, and MR was 0.07 ± 0.01 mm, 0.08 ± 0.04 mm, 0.15 ± 0.03 mm, and 0.14 ± 0.05 mm, respectively, with IOS and MR showing higher FRE than FM and RM. The mean TRE was 0.39 ± 0.03 mm (FM), 0.40 ± 0.03 mm (RM), 0.43 ± 0.03 mm (IOS), and 0.42 ± 0.02 mm (MR). Statistical analysis confirmed non-inferiority of all three techniques compared to the control. In conclusion, this strategy demonstrated accuracy and feasibility, offering a foundation for advancements in IGCRS surgery. Further experiments and clinical trials are necessary to validate these techniques in actual robotic surgeries.

The internal jugular vein (IJV) and omohyoid muscle are important surgical landmarks for the oncological neck dissection procedure. In the normal scenario, the IJV runs under the omohyoid muscle. Although many anatomical variations have been described in the literature, the current report concerns a rare case wherein this relationship was reversed, with the IJV passing over the omohyoid muscle. It appears that this anomaly has not been reported previously. The current report discusses how this rare finding was successfully managed during the surgery and focuses on the clinical implications.

The aim of this study was to compare implant accuracy and surgical efficiency between single-arm and dual-arm dental implant robots. In vitro resin models were printed using preoperative CBCT reconstructions of a real patient's maxilla. Robotic computer-assisted implant surgeries were then performed using single-arm and dual-arm robots. Surgery times were recorded. Postoperative CBCT scans were acquired to compare implant position accuracy. At the immediate implant site, there was no significant difference in deviation between the single-arm and dual-arm implant robots (mean platform, apex, and angular deviation of 0.90 ± 0.16 mm, 0.91 ± 0.12 mm, and 0.54 ± 0.10° versus 0.88 ± 0.14 mm, 0.97 ± 0.13 mm, and 0.55 ± 0.10°, respectively). Results were similar at the delayed implant site (mean deviations of 0.44 ± 0.17 mm, 0.45 ± 0.16 mm, and 0.59 ± 0.18° versus 0.49 ± 0.18 mm, 0.46 ± 0.21 mm, and 0.51 ± 0.10°, respectively). The mean total operation time was 25.04 ± 0.35 min and 22.66 ± 0.81 min (P < 0.001). When used in implant procedures, there was no significant difference in position accuracy between the two robots. However, the single-arm robot took slightly more time.

Le Fort I osteotomy is a common orthognathic surgery procedure, but can result in unpredictable nasolabial changes, highlighting the need for a greater understanding of its effects on the soft tissue and evaluation of alternative techniques. The aim of this study was to compare the subspinal Le Fort I osteotomy (SSLFI) to conventional Le Fort I osteotomy (cLFI) regarding their impact on the nasolabial angle (NLA), with the goal of clarifying their clinical implications and assessing the utility of the subspinal approach. This retrospective analysis included 38 patients who underwent maxillary advancement between 2010 and 2023, using either the cLFI or SSLFI. Soft tissue changes were evaluated at a minimum of six months postoperatively, corresponding to the early healing phase when some residual swelling may persist. The mean maxillary advancement was 6.16 mm in the cLFI group and 6.37 mm in the SSLFI group. NLA tended to decrease in the cLFI group and increase in the SSLFI group, with the most pronounced differences observed when advancement exceeded 5 mm. Sex had no effect on NLA change. These findings underscore the importance of careful surgical planning and patient counseling, while recognizing that soft tissue adaptations may continue beyond the early postoperative period.