Search Results (44)

Background/Objectives: Orthognathic surgery is performed to improve facial esthetics and function in patients with dentofacial deformities. This study aimed to evaluate the impact of orthognathic surgery on perceived facial age using an artificial intelligence (AI)-based age-estimation tool and to examine accompanying changes in self-rated flourishing and social appearance anxiety. Methods: This retrospective, single-arm, before-and-after study included 27 patients who underwent bilateral sagittal split ramus osteotomy (BSSRO) and/or Le Fort I osteotomy. Preoperative and postoperative standardized frontal photographs were analyzed with the AI-based application “AgeBot: How Old Do I Look?”. Participants also completed the Social Appearance Anxiety Scale (SAAS) and the Flourishing Scale (FS; Turkish adaptation by Telef). Both questionnaires were completed at a single postoperative interview—first for the remembered preoperative state and then for the current postoperative state—so the psychosocial pre–post comparisons reflect retrospectively perceived change. Normality was assessed on the paired differences; the primary AI-age outcome was analyzed with the paired t-test (confirmed by the Wilcoxon signed-rank test) and the psychosocial outcomes with the Wilcoxon signed-rank test, with effect sizes reported. A data-informed sensitivity analysis, rather than an a priori power calculation, accompanied the primary outcome. Results: AI-estimated facial age did not change significantly after surgery (mean difference [preoperative−postoperative] 0.11 ± 2.49 years, 95% CI −0.87 to 1.09, p = 0.818; Cohen’s dz = 0.04), and the confidence interval excluded the previously reported 1.31-year reduction. Exploratory change-score comparisons showed no significant differences by sex or smoking status. Postoperative SAAS scores were lower than retrospective preoperative scores (median 37 [IQR 24.5–42.0] vs. 51 [43.0–56.0]; Z = −4.07, p < 0.001, r = 0.55), and postoperative FS scores were higher (median 46 [40.0–51.5] vs. 45 [38.5–45.0]; Z = −2.45, p = 0.014, r = 0.37). Conclusions: Orthognathic surgery was not associated with a statistically significant change in AI-estimated facial age in this small cohort. More favorable social appearance anxiety and flourishing scores were observed following treatment, but the retrospective, uncontrolled assessment precludes causal attribution. AI-assisted facial age estimation may complement patient-reported outcomes, but validated, repeatability-tested tools are required before it can serve as a primary outcome measure. Full article

Objectives: The objective of this study was to conduct three-dimensional cone-beam computed tomography (CBCT) analysis of posterior mandibular anatomy in order to investigate its potential correlation with the occurrence of bad splits during sagittal split osteotomy (SSO). Methods: A retrospective review was conducted on 56 patients (112 hemimandibles) who underwent bilateral SSO between 2016 and 2022. Distances between the mandibular canal and the borders of the mandible, along with anatomical landmarks, were measured. Sites with and without bad splits were compared using chi-square and Mann–Whitney U tests (p = 0.05). Results: The overall incidence of bad split was 8.9% per site (10/112) and 14.3% per patient (8/56). Patient-related variables, including age, sex, skeletal deformity type (Class II vs. Class III), and the presence of impacted third molars, were not significantly associated with bad split (all p > 0.05). Among the morphometric parameters, the distance from the mandibular canal to the inferior cortical border at the mesial of the second molar (M2inferior) was significantly greater in the bad-split group (p = 0.04). Other measurements, including ramal thickness, anteroposterior length, and canal position relative to buccal and inferior cortices, were not significantly different. Reliability analysis demonstrated good to excellent agreement for all measurements. A greater inferior mandibular border thickness at the mesial of the second molar appears to increase the risk of a bad split during SSO. Conclusions: Routine preoperative CBCT evaluation and careful attention to inferior border osteotomy in this region may help reduce complications. Further prospective, standardised studies are needed to confirm these findings. Full article

The selection of an appropriate fixation system is critical for maintaining postoperative stability after sagittal split ramus osteotomy (SSRO), especially in cases involving large mandibular advancements and counterclockwise rotation, where mechanical stresses may compromise treatment outcomes. This in vitro study evaluated the biomechanical stability of five fixation systems following sagittal split ramus osteotomy (SSRO) under two mandibular advancement conditions. Fifty polyurethane hemimandibles were allocated into two experimental groups: Group 1, submitted to 10-mm linear advancement, and Group 2, submitted to 10-mm advancement associated with 20° counterclockwise rotation. Each group was further divided into five subgroups according to the fixation design employed: (A) conventional straight plate, (B) angled plate, (C) sagittal plate, (D) 10-hole miniplate, and (E) two 4-hole miniplates. Biomechanical performance was assessed by compression testing using a universal testing machine. Complementary analyses were performed using strain gauges and digital image correlation. Group 1 in fixation B, C and D demonstrated higher biomechanical resistance than Group 2, however without significance difference. Among the evaluated configurations, subgroup E exhibited the highest resistance values in both experimental conditions. Statistically significant differences were observed among fixation systems within each group (p < 0.05). The fixation systems using two miniplates demonstrated superior biomechanical stability, particularly in mandibular advancements associated with counterclockwise rotational movements. These findings suggest that this fixation strategy may contribute to enhanced postoperative stability in orthognathic surgery involving large mandibular advancements and complex rotational movements. Full article

Background and Objectives: Maintenance of condylar position during bilateral sagittal split ramus osteotomy (BSSRO) is important for preserving temporomandibular joint biomechanics and skeletal stability. During surgery, loss of muscle tone under general anesthesia may alter the condyle–fossa relationship, making accurate repositioning of the proximal segment challenging. Although manual positioning remains the most commonly used intraoperative approach, evidence regarding its ability to preserve the preoperative condyle–fossa relationship remains limited. This study evaluated changes in the condyle–fossa relationship following BSSRO performed with manual proximal segment positioning. Materials and Methods: This single-center retrospective study included lateral cephalometric radiographs of 14 patients (8 females, 6 males; aged 19–29 years) with skeletal Class III malocclusion treated with combined orthodontic treatment and BSSRO. Radiographs were obtained preoperatively (T0), immediately postoperatively (T1), and at the final follow-up examination (T2). Condylar position was assessed using a Cartesian coordinate system, joint space measurements, and the Condyle Position Index (CPI). Statistical analyses were performed using the Friedman and Wilcoxon signed-rank tests (p < 0.05). Results: Significant differences were observed in CPI and anterior joint space measurements across the observation periods. Interval analysis demonstrated increased CPI values and decreased anterior joint space measurements between T1 and T2, whereas no significant immediate postoperative changes were observed. Intra-observer reliability was excellent, with intraclass correlation coefficients exceeding 0.90 for all variables. Conclusions: Manual positioning of the proximal segment during BSSRO may provide acceptable immediate postoperative condyle–fossa stability but may not completely maintain the preoperative condyle–fossa relationship over time. Although no significant immediate postoperative changes were observed, significant changes in the condyle–fossa relationship were identified at the final follow-up examination. These findings support the need for further prospective studies incorporating clinical temporomandibular joint assessment and three-dimensional imaging. Full article

Background/Objectives: The aim of this study was to investigate the association between patient demographics and overall operating time during bilateral sagittal split osteotomy (BSSO). Methods: For this retrospective study, data were collected from patients who had undergone BSSO in our hospital between 2016 and 2023. The mandibular body and mandibular ramus were evaluated from preoperative computed tomography (CT), and CT attenuation values of cortical and cancellous bone in the mandibular ramus were obtained from standardized preoperative CT images. Patient demographics (age, sex, occlusal class, and body weight) before surgery were also collected from the medical record. Results: Forty-six patients were included in this study. Weight and CT attenuation of the mandibular ramus (both cortical and cancellous bone) correlated with operating time (weight: rs = 0.304, p = 0.04; CT attenuation of mandibular ramus: rs = 0.323, p = 0.029). In addition, the Mann–Whitney U test revealed significantly greater operating time in males (p < 0.05). Effects of each variable were estimated after adjusting for other variables, and CT attenuation of the mandibular ramus (both cortical and cancellous bone) (B = 0.088, p = 0.008) was identified as having an effect on operating time. Higher CT attenuation, reflecting greater cortical and cancellous bone density, may increase resistance during osteotomy and consequently prolong operating time. Conclusions: This pilot study observed a possible association between CT attenuation of the mandibular ramus and operating time in BSSO. However, these findings are preliminary and do not imply any causal relationships. Thus, further studies with larger cohorts are required to confirm these observations. Full article

Background/Objectives: Inferior alveolar nerve injury is a common complication of Bilateral Sagittal Split Osteotomy. Preoperative three-dimensional tracing of the mandibular nerve canal using Cone-beam CT may help reduce this risk. We reconstructed the nerve course in 428 consecutively planned BSSO cases and developed a statistical model that quantifies population-level canal position to guide safe, evidence-based osteotomy planning. Methods: Traceable mandibular nerve canal CBCTs from 440 BSSO candidates (2023–2025) were retained. The mandibles and 2.5 mm diameter canals were segmented in Mimics and fused with intraoral scans. Next, the meshes were aligned non-rigidly to a template. A k-nearest-neighbour analysis mapped the outer mandibular surface to canal distances of all the patients on the template mandible model. Results: After excluding 12 scans because the nerve could not be traced, 428 mandibles were studied. The canal’s position varied, with regions near the vertical ramus and premolar regions frequently showing fewer than 3 mm of buccal bone covering the mandibular nerve. In contrast, a preferred safe zone was identified in the second molar region, where more than 97.8% of patients had greater than 5 mm of buccal bone clearance. A population-based colour map was generated to visualise the risk areas and confidence intervals for outer cortex-to-canal distances. Conclusions: This study provides the first high-resolution, population-based 3D map of nerve clearance in BSSO patients. Routine use of CBCT with patient-specific nerve tracing is recommended to reduce the risk of nerve injury. Full article

Advanced cases of unilateral condylar hyperplasia might need combined joint reconstruction and orthognathic surgery. This report illustrates the feasibility of integrating digital planning, patient-specific prosthesis design, and orthognathic correction within a single-stage surgical workflow. A 23-year-old female patient presented with skeletal Class III malocclusion, facial asymmetry, and mandibular midline deviation due to left condylar hyperplasia. After preoperative orthodontic alignment, virtual surgical planning was carried out using specialised software to simulate resection of the hyperplastic condyle, with concurrent total TMJ replacement, contralateral sagittal split ramus osteotomy, and Le Fort I osteotomy. Based on this plan, patient-specific prosthetic components, surgical guides, and fixation plates were designed and manufactured. Surgery was performed according to the digital plan using a combined intraoral and extraoral approach. At 3-month follow-up, clinical and radiological assessments showed stable prosthesis positioning, improved occlusal relationships, restoration of facial symmetry, and high patient-reported satisfaction. However, given the single-case design and short follow-up, these findings should be considered preliminary, and further studies are necessary to evaluate long-term functional outcomes and reproducibility. Full article

Background: In orthognathic surgery planning, two main approaches are commonly used: the conventional orthodontic–surgical (COS) approach and the surgery-first (SF) protocol. The aim of this study was to comparatively evaluate trabecular bone changes in the mandibular condylar, angular, and molar regions following COS and SF protocols using fractal analysis (FA). Methods: A total of 40 individuals (21 females, 19 males) who underwent bilateral sagittal split ramus osteotomy and Le Fort I osteotomy were included in the study. Patients were divided into COS and SF groups. Trabecular changes in the mandibular osteotomy line, condylar, and angular regions were evaluated on panoramic radiographs using FA, and fractal dimension values were calculated using the box-counting method. Results: No statistically significant differences were found between the groups in terms of baseline and post-treatment FA values in the molar and angular regions (p > 0.05). In contrast, a statistically significant difference was observed between the groups in the condylar region (p ≤ 0.05). The total treatment duration was significantly shorter in the SF group (p < 0.05). Conclusions: FA findings reveal that COS and SF protocols show similar effects in terms of mandibular bone healing, but the surgery-first approach is preferable due to its clinical advantages. Full article

Background/Objectives: Sagittal split ramus osteotomy (SSRO) is a widely used method in the treatment of mandibular deformities. However, high parafunctional forces associated with bruxism can negatively affect stability at the osteotomy site. Botulinum toxin A (BoNT-A), which reduces masseter activity, is considered an additional approach to controlling these forces. Methods: In this comparative finite element study, five different fixation configurations were created on a three-dimensional mandibular model and evaluated under identical boundary conditions using both a 1000 N bruxism-related parafunctional loading and a standardized force-reduction scenario. The stress distributions and displacement amounts on the cortical bone, screws, and plates were examined in each model. Results: The stress distribution was more balanced in the model with double plates, whereas the stress and displacement values were found to be greater for fixations with single plates and only bicortical screws. Under the standardized force-reduction scenario, lower stress and displacement values were observed across all the models. Conclusions: Among the evaluated fixation configurations, the double-plate model demonstrated the most balanced stress distribution. Under the standardized force-reduction scenario, lower stress and displacement values were observed across all the models; these findings reflect the load sensitivity of the fixation constructs and should not be interpreted as evidence of clinical efficacy. Full article

Background/Objectives: Mandibular counterclockwise (CCW) autorotation following maxillary repositioning is a common biomechanical consequence of bimaxillary orthognathic surgery. However, its effect on temporomandibular joint (TMJ) morphology remains controversial. This study aimed to evaluate whether condyle-centered CCW mandibular autorotation influences postoperative TMJ spaces and condylar morphology using cone-beam computed tomography (CBCT). Methods: A total of 24 patients who underwent combined Le Fort I osteotomy and bilateral sagittal split ramus osteotomy were included in this retrospective analysis. Patients were divided into two groups based on virtual surgical planning: those with condyle-centered CCW autorotation (4–7°) and those without autorotation. Preoperative and one-year postoperative CBCT images were analyzed. Sagittal and coronal joint spaces, condylar dimensions, and glenoid fossa thickness were measured. Intra- and intergroup comparisons were performed using nonparametric statistical tests (α = 0.05). Results: Both groups demonstrated significant postoperative reductions in condylar height, width, and depth, reflecting adaptive bone remodeling. Joint space changes were limited overall. A significant intergroup difference was observed only in the change in the right superior joint space (p = 0.024), which decreased in the non-autorotation group but was preserved or slightly increased in the autorotation group. No other joint space or fossa parameter showed significant between-group differences. Conclusions: Condyle-centered CCW mandibular autorotation during bimaxillary orthognathic surgery does not induce adverse TMJ morphological changes beyond physiological adaptation. Preservation of the superior joint space suggests that autorotation may contribute to maintaining a more favorable condyle–fossa relationship. Incorporating controlled mandibular autorotation into surgical planning may support TMJ biomechanical balance and postoperative joint stability. Full article

In addition to standardized lateral cephalometric radiographs, comprehensive assessment using dental cone-beam computed tomography (CBCT) and CT has become commonplace in the diagnosis and treatment of jaw deformities. Simulation based on cephalometric and CT data is particularly useful in the management of jaw deformities, both for evaluation and prognostic prediction. As such imaging examinations cover a wide anatomical region, it is not uncommon for various incidental pathologies to be discovered. This review emphasizes the necessity of evaluating the entire imaged area in addition to the chief complaint. Furthermore, it outlines the essential anatomical structures that should be assessed during diagnostic imaging performed prior to representative surgical procedures for jaw deformities (e.g., sagittal split ramus osteotomy and Le Fort I osteotomy). This review paper is descriptive in nature, incorporating our facility’s empirical aspects, and presents representative cases in a narrative format; it is not a systematic review. In other word, as the evidence-based literature does not cover all aspects of pretreatment evaluation, these criteria are based on the past experience of the authors. Full article

Orthognathic surgery, particularly maxillomandibular advancement (MMA), has emerged as an effective therapeutic option for patients with moderate to severe OSA who are refractory to conventional treatments. The wedge osteotomy of the maxilla, often performed in combination with mandibular surgery, can be a surgical treatment for obstructive sleep apnea (OSA). This case series report describes 6 OSA patients without anteroposterior maxillary deficiency who were treated with wedge osteotomy of the maxilla. Material and Methods: We conducted a retrospective analysis of 6 patients who underwent maxillomandibular advancement (MMA) for obstructive sleep apnea (OSA), all operated on consecutively by the same surgeon between 2018 and 2024 at the Maxillofacial Surgery of San Camillo-Forlanini Hospital, in Rome, Italy. Patients were evaluated using a CAD/CAM-assisted approach. A pre- and postoperative comparative analysis was conducted to assess the effectiveness of the surgical treatment in improving OSA-related parameters. Maxillary wedge osteotomy and bilateral sagittal split osteotomies (BSSO) of the mandibular ramus were digitally planned. Results: The comparison between preoperative and postoperative CT scans, along with 3D reconstructions generated using dedicated software, revealed a counterclockwise rotation of the occlusal plane, resulting in a mandibular advancement of approximately 13 mm. The CT shows a significant increase in airway volume following the skeletal repositioning. The airway volume increased from 20.665 ± 546 mm³ to 27.177 ± 446 mm³. Conclusions: Counterclockwise rotational orthognathic surgery without maxillary advancement has been shown to effectively enlarge the posterior pharyngeal space while also delivering excellent esthetic outcomes. Full article

Background/Objectives: The mandibular lingula (ML) is a small bony projection on the medial surface of the ramus and serves as the first reference point identified during sagittal split ramus osteotomy (SSRO) or inferior alveolar nerve block (IANB). Anatomical variations in the mandibular ramus have been shown to exist across different populations. Understanding these population-specific differences enhances both clinical safety and diagnostic precision. However, there is a paucity of anthropological data amongst the Mongoloid population, especially in Southeast Asia. Hence, this study aimed to investigate the (i) distance of the lingula to different mandibular anatomical landmarks and its localization, (ii) lingula shape, and (iii) differences between gender and the sides of the mandible amongst the local ethnic groups. Methods: This retrospective cross-sectional study consisted of 206 cone-beam computed tomography (CBCT) images of 77 males and 129 females (mean age 33), with a total of 412 hemimandibles. Measurements were performed on three-dimensionally reconstructed CBCT images. Results: The most common shape was the truncated type. The distance of the lingula to the anterior (LiA), posterior (LiP), superior (LiS), and inferior (LiI) borders of mandible were 17.84 (2.25) mm, 14.46 (3.44) mm, 17.73 (3.00) mm, and 27.05 (4.40) mm, respectively. No significant difference exists between the sides of the mandible. Sexual dimorphism existed for all lingula measurements except LiA. Indians have smaller rami with more anteriorly and inferiorly placed ML than Malay and Chinese. The majority of ML was located 8.55 mm above the occlusal plane. Conclusions: This study provides information on the ML and its surrounding ramus structure in the local population. Such variations must be accounted for in SSRO and IANB. Full article

This study aimed to evaluate mandibular fixation techniques using monocortical plates following sagittal split ramus osteotomy in skeletal Class III patients. Ninety-three patients were categorized into three groups based on fixation methods: four-hole miniplate with one proximal and two distal screws (Group 1); four-hole miniplate with four screws (Group 2); sliding plate with two proximal and one distal screws (Group 3). Cone-beam computed tomography scans were obtained at three time points: immediately postoperative (T1), 6 months (T2), and 12 months (T3). The yaw, roll, and pitch rotations of the proximal segment, as well as horizontal and vertical changes of the pogonion, were evaluated. Group 1 exhibited significantly greater counterclockwise rotation of the proximal segments at T2 (p = 0.021) and T3 (p = 0.035) compared to the other groups. Additionally, Group 1 showed significantly smaller anterior and superior displacement of the pogonion at T3 (0.97 ± 2.10 mm, p = 0.009; 0.03 ± 1.62 mm, p = 0.011, respectively). Following surgical wafer removal, intimate occlusal contact is archived and the elimination of premature contacts through postoperative orthodontic treatment contributes to counterclockwise autorotation of the mandible. Therefore, anterior and superior movements of the pogonion are expected if firm fixation between the proximal and distal segments is achieved. Therefore, these findings suggest that a single proximal screw, as seen in a three-screw fixation, may act as a fulcrum, insufficiently resisting postoperative clockwise rotation of the distal segments. Full article

Background/Objectives: Sagittal split ramus osteotomy (SSRO) is a commonly performed procedure in orthognathic surgery. Despite its effectiveness, surgical site infections (SSI) represent a significant postoperative complication, often necessitating the removal of osteosynthesis materials. This study aims to quantify the prevalence of hardware removal due to SSI following SSRO highlighting its impact on clinical outcomes. Methods: A systematic review and meta-analysis were conducted according to the PRISMA statement. Databases including Medline/PMC Central, Scopus, and Web of Science were searched up until 27 December 2024. Observational studies reporting osteosynthesis material removal due to SSI after SSRO were included. Data were extracted and analyzed using a random-effects model, calculating pooled prevalence and 95% confidence intervals (CI). Meta-regression was performed to explore potential predictors. Results: Twenty-nine studies published between 1992 and 2024 were included, encompassing 4489 patients. The pooled prevalence of osteosynthesis material removal due to SSI was 1.9% (95% CI: 0.7–3.4%), with substantial heterogeneity (I² = 87%). Meta-regression demonstrated that the mean age of patients was significantly associated with the prevalence of osteosynthesis hardware removal due to SSI. On the other hand, no significant association was demonstrated between the year of publication, the proportion of males, or the mean age with the prevalence of removal. Conclusions: SSI following SSRO clearly impacts patient outcomes and healthcare resources, while removal of osteosynthesis materials is often required. The substantial heterogeneity among studies included in the present systematic review may point to variability in patient characteristics, surgical techniques, and healthcare practices. The present findings underscore the importance of standardized prevention protocols and targeted management strategies. Future research should focus on understanding microbial profiles, patient-specific risk factors, and innovative surgical approaches to minimize SSI risks and improve patient outcomes. Full article