Protecting the adjacent soft tissues using a channel retractor prevents complications, such as excessive bleeding, during sagittal split ramus osteotomy. However, the saucer-shaped blade of the conventional channel retractor fits poorly into the posterior border of the mandibular ramus during medial osteotomy, which is typically performed parallel to the occlusal plane. Therefore, a novel channel retractor was developed with an adjusted blade bending angle, based on cephalometric data. The lateral cephalograms of 339 Japanese patients with jaw deformities were collected. Cephalometric landmarks were identified based on the definitions of the Downs-Northwestern analysis, and the acute angle between the occlusal and ramus planes was calculated. Based on the consistent mean and median occlusal ramus angles obtained, the blade was bent at 70° in the sagittal plane to fabricate the angled channel retractor. The engagement at the posterior border of the mandibular ramus during medial osteotomy enhances its stability. Furthermore, owing to the bending direction, the angled channel retractor used for medial osteotomy on one side can be used as a channel retractor for lateral osteotomy on the other side. The proposed angled channel retractor offers both stability and versatility for osteotomy manoeuvres.

The aim of this study was to develop a model for predicting the risk of postoperative temporomandibular joint osteoarthritis (TMJOA) in patients receiving a segmental or marginal mandibulectomy for oral cavity cancer . A total of 371 patients with buccal or gingival cancer who underwent mandibulectomy were included in this retrospective cohort study. Demographic data, computed tomography, and magnetic resonance images were reviewed. Univariate and multivariate Cox regression analyses were performed to develop a nomogram to predict post-mandibulectomy TMJOA. TMJOA was identified in 81 of the 371 patients at 2 years and 107 at 4 years. The predictors of post-mandibulectomy TMJOA were segmental mandibulectomy (hazard ratio (HR) 2.51, 95% confidence interval (CI) 1.64-3.83, P < 0.001), age ≥ 62.5 years (HR 2.28, 95% CI 1.53-3.40, P < 0.001), BMI < 24.1 kg/m (HR 2.13, 95% CI 1.45-3.13, P < 0.001), and American Joint Committee on Cancer stage IVa/IVb (HR 2.21, 95% CI 1.38-3.56, P = 0.001). The nomogram developed in this study exhibited good predictive capacity (area under the curve 0.742, 95% CI 0.679-0.804). The proposed model for predicting post-mandibulectomy TMJOA in patients with buccal or gingival cancer can identify high-risk individuals for early preventive oral rehabilitation.

Malignant tumors of the nasal and paranasal cavities account for only 3-5% of all head and neck neoplasms. Among these tumors, rare instances of human papillomavirus (HPV)-positive multiphenotypic carcinomas and biphenotypic sarcomas have been documented. Two such cases are reported here, along with the respective treatment approaches. The first involved a 39-year-old male patient diagnosed with HPV-positive multiphenotypic carcinoma. Surgical treatment was performed through a craniofacial and transfacial approach, en bloc resection, and reconstruction of the anterior cranial base with a fascia lata graft and pericranial flap. The second involved a 41-year-old female patient diagnosed with biphenotypic sarcoma. Surgical treatment was performed through centripetal endoscopic tumour resection. In both cases, adjuvant radiotherapy was performed after obtaining the histopathological result and negative margins. Both patients were free of disease during postoperative follow-up. Given the rarity of these cases, there are no established guidelines outlining specific treatments. It is recommended that such tumours are assessed in interdisciplinary committees to determine the optimal treatment options. Typically, this will involve surgical resection via craniofacial and transfacial approaches or endoscopic surgery, depending on the diagnosis, extent of anatomical involvement, and tumour aggressiveness. Additionally, the potential benefits of adjuvant radiotherapy should be evaluated, as it has demonstrated promising outcomes, even in cases with positive margins.

The aim of this study was to evaluate dental and periodontal injuries and radiological bone healing at vertical osteotomies in patients treated with segmental Le Fort I (LFI) osteotomy, using cone beam computed tomography (CBCT) scans. This retrospective study analyzed 105 patients who underwent segmental LFI osteotomy. Vertical osteotomies were performed between the lateral incisor and canine using a bur and osteotome. CBCT scans were taken preoperatively and at 1-week and 1-year follow-ups. Measurements at 1-week included interdental distances, root injuries, and periodontal detachment, while 1-year follow-up assessed endodontic treatment and osteotomy healing. Results showed no damage to the 420 roots at risk, though 38 roots had osteotomy extensions into the periodontal ligament. The mean preoperative minimum distance between roots was significantly different between sites with intact and detached periodontal ligaments (P < 0.001). One tooth required endodontic treatment at 1-year follow-up. Incomplete healing of vertical osteotomies was more frequent in female patients (P = 0.012). The findings suggest that segmental LFI osteotomy is safe when performed with a bur and osteotome, provided a minimum distance of 2.5 mm between roots is maintained.

The aim of this study was to assess the value of the use of software for the preoperative evaluation of cranial bone thickness in syndromic patients undergoing Le Fort III osteotomy. Four patients were evaluated preoperatively to determine whether they were eligible for distraction osteogenesis. Data from the computed tomography scans was evaluated using advanced reverse engineering tools to determine the temporal bone thickness. Three patients showed adequate values for the positioning of a rigid external distractor device (average thickness values >3.5 mm), while one patient showed insufficient bone thickness (average value <2.5 mm) and therefore underwent midface advancement according to the traditional technique. Adequate midface advancement was obtained in the three patients who underwent distraction osteogenesis. No complications related to the rigid external distractor were observed. A shorter skeletal advancement was obtained in the patient who underwent Le Fort III osteotomy according to the traditional technique. A cerebrospinal fluid fistula was observed after the removal of the plates, requiring surgical repair. Software evaluation of the cranial bone thickness is a useful tool in the surgical planning of Le Fort III osteotomy in patients affected by syndromic craniosynostosis.

The chin is a major functional and aesthetic anatomical unit of the face. The correction of bony abnormalities is common in orthognathic surgery, but the management of the soft tissues is complex. This article describes a genioplasty technique focused on the soft tissue. The procedure improves the chin morphology in patients with a sharp lower lip-chin prominence angle or sagittal prominence of the chin soft tissue, with or without correction for bone malposition. Furthermore, this procedure can be performed on an outpatient basis. It can also be combined with conventional osteotomy.

Evidence was reviewed to assess the decrease in compressive strength postoperatively. The PRISMA guidelines were followed. PubMed, Embase, Web of Science, Google Scholar, and ProQuest were searched. Five cadaver studies met the inclusion criteria (49 cadavers). Three reported force leading to fracture (FLF), which ranged between 1034 N and 9962 N consistently higher than three times cadaver body weight. Only one reported statistically significant lower FLF in decancellated tibias compared to the contralateral tibias (mean 3766.9 N vs 5126.4; stability reduction 26.5%). The overall estimate of FLF in decancellated tibias was 4321.6 N (95% confidence interval 3434.4-5208.8 N. Meta-analysis estimated a significant difference in force leading to fracture (ΔFLF) 1098.1 N, 95% confidence interval 547.8-1648.5 N. While mean FLF in all studies and the pooled data was above a force three times the body weight of an average adult (70 kg x 3 = 2100 N), three cadavers showed FLF values below this threshold. Increasing the threshold to 2400 N (roughly relating to a body weight of 80 kg, increased this number to six. Normal weight-bearing after decancellation seems to be statistically safe. Clinically, however, the authors are not able to generalize this assumption.

The survival rate of implants placed at sites of previous failures including the best treatment strategies remain unclear. This systematic review was performed to assess implant survival and peri-implant health for such cases, including subgroup analyses of immediate versus delayed implant placement and augmentation. Four electronic databases were searched. Meta-analyses including subgroup analyses were performed (PROSPERO CRD42024548610). Out of 1798 records identified, 24 studies were included. The 1-year implant survival rate after replacement was 96.7% (95% confidence interval (CI) 92.8-99.3%), with no significant difference between immediate and delayed placement (P = 0.31) or immediate and delayed augmentation (P = 0.85). Immediate augmentation showed higher overall implant survival (97.6%, 95% CI 93.4-99.9%) compared to delayed augmentation (91.7%, 95% CI 83.4-97.5%), although not statistically significant (P = 0.26). Peri-implant health outcomes, including marginal bone loss, were similar across subgroups. Second implant replacements had lower survival rates than first replacements. Replacement of the failed implant is an appealing treatment option for failed implants, although the implant survival is lower compared to initially placed implants. Immediate implant placement can be done if sufficient bone is present. If insufficient bone remains after removal, immediate augmentation followed by delayed implant placement is recommended.

Prostheses for extended total temporomandibular joint replacement (eTJR) include modifications to the traditional alloplastic fossa-condyle joint that extend to adjacent bone defects. The aim of this retrospective study was to assess the feasibility, postoperative complications, and functional and aesthetic outcomes after eTJR. Patients aged ≥18 years undergoing eTJR between 2013 and 2022 were included. Data recorded were age, sex, comorbidities, indication for eTJR, prosthesis brand, classification, concomitant surgical procedures, postoperative complications, maximum inter-incisal opening (MIO), pain, quality of life (QoL), and aesthetic outcome. Twenty-five patients (mean age 40 years), with a total of 30 joint prostheses, were included. Over a median follow-up of 42 months, there was a significant improvement in MIO in patients with reduced mouth opening at baseline (P = 0.003), as well as in pain (P = 0.007) and QoL (P = 0.004). Both patients and surgeons judged facial appearance as improved or unchanged in 88% of cases. Postoperative complications included permanent trigeminal nerve hypoesthesia (44%), permanent facial nerve dysfunction (35%), infection (8%), salivary leak (4%), and lingual nerve impairment (4%). The findings suggest that eTJR is a safe and effective treatment for temporomandibular joint deficits extending to adjacent structures, yielding satisfactory functional and aesthetic outcomes.

The last decades have witnessed significant improvements in orthognathic surgery, but a true standardization of cephalometric analysis to guide clinical assessment in three-dimensional (3D) virtual planning is still lacking. Therefore, the aim of this study was to validate the 'total face approach' (TFA) 3D cephalometric model for the diagnosis of dysmorphia and to analyse its correlation with the clinical diagnosis and virtual surgical planning performed in the Maxillofacial Surgery Clinic in Udine. This model was validated by studying different cephalometric points in three modules (vertical dimensions, sagittal dimensions, and symmetry) and their sections. Each section of the different modules evaluates the range of the studied patient according to the TFA analysis executed in Planmeca Romexis software and compares it with the ProPlan CMF data. The results of the statistical analysis defined the degree of concordance for each point studied. An overall high correlation was demonstrated for each of the cephalometric categories (weighted kappa between 0.442 and 0.642 in vertical dimension, between 0.587 and 1 in sagittal dimension, and between 0.773 and 1 in symmetry). The TFA model can be considered a valuable guide for the diagnosis of dysmorphia and 3D virtual planning of orthognathic maxillofacial surgery.

The aim of this retrospective study was to evaluate the morphological changes in the mandibular angle area after orthognathic surgery with or without mandibular counterclockwise rotation in Class II deformity patients, and to investigate the associated factors. Computed tomography scans obtained preoperatively (T0), within 1 month postoperatively (T1), and 6 months postoperatively (T2) were collected from 58 patients who underwent either bilateral sagittal split ramus osteotomy (group I), bimaxillary surgery with mandibular counterclockwise rotation (group II), or bimaxillary surgery without mandibular counterclockwise rotation (group III). The intergonial width increased after surgery, by 2.78 ± 2.02 mm in group I, 2.86 ± 2.81 mm in group II, and 2.53 ± 2.42 mm in group III (all P < 0.001). The mandibular angle (MA) increased in group I (ΔMA 4.76 ± 2.79°; P < 0.001) and group III (ΔMA 3.50 ± 2.58°; P < 0.001); however no significant increase was observed in group II. The increase in intergonial width was positively correlated with the lateral displacement of the proximal segment. Counterclockwise rotation of the proximal segment resulted in an increase in MA, while counterclockwise rotation resulted in a reduction in this increasing trend. The results indicate that reducing the displacement and rotation of the proximal segments is key to minimizing changes in the mandibular angle area.

Vascular complications occurring in Eagle syndrome are seldom described. The aim of this study was to systematically review the occurrence, characteristics, and management outcomes of vascular complications occurring in Eagle syndrome. A systematic review was conducted with a search in several databases. The research question was "What characterizes Eagle syndrome with vascular complications and how should it be managed?" The initial search yielded 4145 results; 150 of these were included, reporting a total of 231 patients with vascular complications. Arterial impingement (67.5%) was more frequent than venous impingement (32.5%). The most frequent consequence of arterial impingement was stroke (46.8%), while for venous impingement it was chronic headache (68%). Seventy-nine patients underwent styloidectomy as initial treatment: 78.5% of the patients were cured and 19.0% improved, while only 2.5% showed a recurrence. On the other hand, among the 106 patients treated medically without initial styloidectomy, only 24.5% of the patients were cured, 28.3% improved, and 47.2% had a recurrence. The association of symptoms of classic Eagle syndrome with neurovascular symptoms should prompt clinicians to consider this diagnosis and to measure the styloid length. Styloidectomy is the treatment of choice to obtain the best cure rate and reduce recurrence.

Temporomandibular joint (TMJ) prostheses are considered an important alternative for the treatment of severe end-stage TMJ disorders. However, unilateral TMJ replacement may affect the healthy contralateral TMJ. The purpose of this study was to systematically review the literature on the effects of unilateral total TMJ prosthesis placement on the contralateral healthy TMJ. The PubMed, Scopus, Web of Science, and Cochrane Library databases were searched for English-language articles published up to December 2023. Inclusion criteria encompassed clinical studies (randomized, prospective, retrospective, observational) that evaluated clinical and patient-reported outcomes after total unilateral TMJ prosthesis placement (both glenoid and mandibular components). The initial search identified 141 non-duplicate studies, of which eight remained after title and abstract reading. Four studies included only unilateral prostheses; the other four included bilateral interventions and/or control groups without any TMJ intervention. The studies reported on stock and custom prostheses, with custom prostheses being the most used. As the studies had different specific objectives, no pattern of data reporting was found and the research question could not be answered. Randomized clinical trials with standardized variables are required to achieve reliable conclusions. Furthermore, long-term follow-up is necessary to determine whether the function of the healthy TMJ is compromised.

The purpose of this study was to evaluate the performance of convolutional neural network (CNN)-based image segmentation models for segmentation and classification of benign and malignant jaw tumors in contrast-enhanced computed tomography (CT) images. A dataset comprising 3416 CT images (1163 showing benign jaw tumors, 1253 showing malignant jaw tumors, and 1000 without pathological lesions) was obtained retrospectively from a cancer hospital and two regional hospitals in Thailand; the images were from 150 patients presenting with jaw tumors between 2016 and 2020. U-Net and Mask R-CNN image segmentation models were adopted. U-Net and Mask R-CNN were trained to distinguish between benign and malignant jaw tumors and to segment jaw tumors to identify their boundaries in CT images. The performance of each model in segmenting the jaw tumors in the CT images was evaluated on a test dataset. All models yielded high accuracy, with a Dice coefficient of 0.90-0.98 and Jaccard index of 0.82-0.97 for segmentation, and an area under the precision-recall curve of 0.63-0.85 for the classification of benign and malignant jaw tumors. In conclusion, CNN-based segmentation models demonstrated high potential for automated segmentation and classification of jaw tumors in contrast-enhanced CT images.

Longitudinal follow-up data of 1557 patients with cleft palate (CP) was used to identify risk factors for palatal fistula (PF) formation after double-opposing Z-plasty (DOZ), performed by a single surgeon. Overall, 104 (6.7%) of the patients developed PF, all of which were identified within the first month following DOZ. The incidence of PF for clefts of Veau class 1, 2, 3, and 4 was 0%, 6.5%, 4.4%, and 20.3%, respectively. The PFs were pinpoint-shaped in 38.5% of cases, slit-shaped in 40.4% (2-8 mm), and other (10-96 mm) in 21.1% . Among patients with PF, 14 (13.5%) chose surgical repair; recurrence was observed in four patients, of whom two showed secondary healing. Among the 90 unrepaired cases, 68 (75.6%) showed symptom resolution, mostly within 1-3 years. Recovery varied by PF size category: 81.1% of pinpoint, 71.4% of slit-shaped, and 100% of other fistulas healed spontaneously over a median 9, 3, and 21.5 months, respectively. Multivariate logistic regression analysis identified cleft width as the most significant predictor of PF development (odds ratio 1.25, P < 0.001), while the Veau classification was not a significant determinant. This study identified cleft width as a critical determinant of the risk of PF following DOZ. A conservative strategy that prioritizes symptomatology over PF size (for PFs <1 cm) is worthy of consideration.

Local anaesthetic injections, commonly used in dentistry and oral surgery, often cause discomfort. This review aimed to examine the impact of intraoral photobiomodulation therapy (PBMT) on pain associated with local anaesthesia. Up to March 2024, two independent reviewers searched four databases, ultimately screening 17 randomized controlled trials for meta-analysis using Stata 17.0. The results indicate that intraoral PBMT application significantly reduces the perception of pain associated with local anaesthetic injections (standardized mean difference (SMD) -0.89, 95% confidence interval (CI) -1.27 to -0.52; P < 0.001). This analgesic effect remained consistent irrespective of concurrent topical anaesthetics, and PBMT was efficacious in paediatric (SMD -0.53, 95% CI -0.89 to -0.17; P = 0.004) and adult (SMD -1.46, 95% CI -2.32 to -0.61; P = 0.001) populations. Subgroup analysis provided very low to low-quality evidence that using a wavelength between 900 nm and 980 nm (SMD -0.87, 95% CI -1.36 to -0.39; P < 0.001) and an irradiation time of 13-40 s (SMD -0.94, 95% CI -1.35 to -0.53; P < 0.001) are associated with significant pain reduction. The use of PBMT could aid in reducing pain perception for patients during dental injections, encouraging earlier presentation for dental consultations.

Midface resection is a surgical procedure with varying degrees of complexity, ranging from partial upper jaw removal to exposure of the dura mater after resection. Existing classifications for the resulting midfacial defects are inconsistent and have issues regarding terminology, therefore a consensus is needed. The aim of this review was to analyse the previously published classifications, identify defining parameters, determine their strengths and weaknesses, and propose a universal classification for midfacial defects with the goal of being sufficiently detailed yet easily applied in clinical practice. A scoping review was conducted according to the PRISMA guidelines using the PubMed, Embase, and Wiley Online Library electronic resources. Analysis of the various midfacial resection classifications identified in the search revealed common parameters including anatomical landmarks, the walls removed, and the presence of oroantral communication, as well as an accompanying algorithm and options for reconstruction. The articles with the most detailed descriptions were noted. A new classification is proposed that includes elements of the three most detailed existing classifications, incorporating the vertical and horizontal extents of the defect, but with more specific details concerning severity and aimed at greater practical clinical utility.

This retrospective study examined factors influencing labial bone resorption in the anterior maxilla 6 months after implant insertion with simultaneous guided bone regeneration. Involving 79 patients (118 implants), the study measured labial horizontal bone width and vertical dimensions using cone beam computed tomography scans taken immediately after surgery and at 6 months. A generalized linear mixed model analyzed potential influencing factors: age, sex, implant site, timing of placement, buccal bone width at the implant platform level post-surgery, implant connection, and bone defect morphology. Significant bone resorption was noted at 6 months. The statistical analysis revealed that buccal bone width at the implant platform, implant connection, and bone defect morphology significantly impacted labial bone resorption, while patient age, sex, timing of placement, and implant site did not. Implants with a buccal bone width ≥2 mm showed significantly less labial horizontal and vertical bone resorption (horizontal P < 0.001, vertical P = 0.001), and healing abutments reduced resorption compared to cover screws (horizontal P = 0.002, vertical P = 0.034). More significant vertical resorption occurred in non-contained bone defects after guided bone regeneration (P = 0.040).

The aim of this retrospective longitudinal study was to investigate the condylar growth after arthroscopic discopexy in adolescents with temporomandibular joint (TMJ) anterior disc displacement without reduction (ADDwoR), and to determine whether local or systemic factors influence this growth. A total of 145 patients aged 10-20 years who were diagnosed with ADDwoR by magnetic resonance imaging were included. Patients who underwent arthroscopic discopexy were assigned to the arthroscopy group (n = 108) and others to the control group (n = 37). Demographic information, clinical assessments, body indicators, and bone density information were collected. Condylar height, disc length, and disc position were measured. The mean condylar height change in the arthroscopy group was 2.12 mm more than that in the control group (P < 0.001). Condylar growth after surgery was negatively correlated with age (P = 0.017) and disc length (P = 0.015), and positively correlated with follow-up duration (P = 0.002) and disc position (P < 0.001). Moreover, arthroscopic discopexy patients had better outcomes regarding improvements in pain (P = 0.024), maximum inter-incisal opening (P < 0.001), and quality of life (P < 0.001) than control patients. In conclusion, arthroscopic discopexy can restore condylar growth and relieve symptoms in ADDwoR patients, and the condylar growth is closely related to the local factors.

Odontogenic cysts are commonly seen in clinical practice. Surgical enucleation of these cysts becomes challenging when they form adjacent to anatomically important structures. Recently, computer-assisted surgery using computer-aided preoperative simulation and augmented reality (AR) has been applied in oral and maxillofacial surgery. The authors have introduced a new AR system that eliminates the need for markers and uses image recognition of the teeth to overlay the surgical field with preoperative surgical simulation images. This report describes two cases of cystectomy performed using an AR-assisted system, one for recurrent odontogenic keratocyst and the other for a dentigerous cyst. The teeth were scanned using a 3D intraoral scanner, while the face was scanned using a computed tomography scanner. A 3D reconstructed image of the mandible was generated, and a dentofacial skeleton model was designed using the intraoral and CT scan data. A camera was used to capture the clinical image and validate the AR. Two cystectomy cases performed using the AR-assisted system and preoperative planning are reported. This new AR system, which eliminates the need for markers and uses image recognition of the teeth to overlay the surgical field with preoperative surgical simulation images, has the potential to provide more accurate and efficient guidance during surgery.