Bimaxillary Orthognathic Surgery Research Articles

Comprehensive 3-dimensional Positional and Morphological Analyses of Condyle and Glenoid Fossa in Patients with Skeletal Class II Malocclusion following Bimaxillary Orthognathic Surgery.

This study aimed to comprehensively and quantitatively characterize 3-dimensional (3D) positional and morphological changes of the condyle and glenoid fossa in patients with skeletal Class II malocclusion treated with bimaxillary orthognathic surgery. Twenty eligible patients treated at our institution from January 2016 to December 2021 with more than 12 months of postoperative follow-up were retrospectively enrolled. Radiographic data of cone-beam computed tomography (CBCT) for each patient were collected at 3 stages: 1 week preoperatively (T0), immediately after surgery (T1), and at least 12 months postoperatively (T2). Positional changes, surface and volumetric alterations of condyle, and bone remodeling in glenoid fossa were measured and compared based on voxel- and surface registrations in visual 3D methods. Most patients exhibited a tendency for condyles to shift posteriorly, laterally, superiorly, and rotated outward, downward, and forward immediately after surgery. Posterior, medial, superior movement and outward, upward, and backward rotation of condyles were observed during follow-up (T1-T2). Bone resorption frequently occurred in the posterior area of condylar surfaces, while bone remodeling was more common in the anterior region of the glenoid fossa. Reduced volume of the condyle was found in most cases, which was not associated with the amount of mandibular advancement. Overall, the condyle and its corresponding glenoid fossa remained relatively stable during the follow-up. Our results reveal positional and morphological alterations in the condyle and the glenoid fossa after bimaxillary orthognathic surgery in patients with skeletal class II malocclusion. These changes predominantly fall within the spectrum of physical adaption.

An automated method for assessing condyle head changes in patients with skeletal class II malocclusion based on CBCT images.

Currently, there is no reliable automated measurement method to study the changes in the condylar process after orthognathic surgery. Therefore, this study proposes an automated method to measure condylar changes in patients with skeletal class II malocclusion following surgical-orthodontic treatment. Cone-beam computed tomography (CBCT) scans from 48 patients were segmented using the nnU-Net network for automated maxillary and mandibular delineation. Regions unaffected by orthognathic surgery were selectively cropped. Automated registration yielded condylar displacement and volume calculations, each repeated three times for precision. Logistic regression and Linear regression were used to analyze the correlation between condylar position changes at different time points. The Dice score for the automated segmentation of the condyle was 0.971. The Intraclass correlation coefficients (ICCs) for all repeated measurements ranged from 0.93 to 1.00. The results of the automated measurement showed that 83.33% of patients exhibited condylar resorption occurring six months or more after surgery. Logistic regression and Linear regression indicated a positive correlation between counterclockwise rotation in the Pitch plane and condylar resorption(p < 0.01). And a positive correlation between the rotational angles in both three planes and changes in the condylar volume at six months after surgery(p ≤ 0.04). This study's automated method for measuring condylar changes shows excellent repeatability. Skeletal class II malocclusion patients may experience condylar resorption after bimaxillary orthognathic surgery, and this is correlated with counterclockwise rotation in the sagittal plane. This study proposes an innovative multi-step registration method based on CBCT, and establishes an automated approach for quantitatively measuring condyle changes post-orthognathic surgery. This method opens up new possibilities for studying condylar morphology.

Effect of tranexamic acid on blood loss reduction in patients undergoing orthognathic surgery under hypotensive anesthesia: a single-center, retrospective, observational study.

Orthognathic surgery is a surgical procedure performed by intraoral approach with established and safe techniques; however, excessive blood loss has been reported in rare cases. In response, investigative efforts to identify methods to reduce the amount of blood loss have been made. Among such methods, the administration of tranexamic acid was reported to reduce the amount of intraoperative blood loss. However, few studies to date have reported the effect of tranexamic acid in orthognathic surgery under hypotensive anesthesia. The present study aimed to investigate the effect of the administration of tranexamic acid on intraoperative blood loss in patients undergoing bimaxillary (maxillary and mandibular) orthognathic surgery under hypotensive anesthesia. A total of 156 patients (mean age, 27.0±10.8 years) who underwent bimaxillary orthognathic surgery under hypotensive anesthesia performed by the same surgeon between June 2013 and February 2022 were included in this study. The following data were collected from the medical records of each patient: background factors (age, sex, and body mass index), use of tranexamic acid, surgical procedures, previous medical history, duration of surgery, American Society of Anesthesiology physical status findings before surgery, intraoperative blood loss as a primary outcome, in-out balance, and blood test results. Descriptive statistics were calculated for statistical analysis, and a t -test and the chi-squared test were used for between-group comparisons. Group comparisons were performed after 1:1 propensity score matching to adjust for confounding factors. Statistical significance was set at P<0.05. Comparison between the groups based on the use of tranexamic acid revealed a significant difference in operation time. Propensity score matching analysis revealed that intraoperative blood loss was significantly lower in the tranexamic acid group. The administration of tranexamic acid was effective in reducing intraoperative blood loss in patients undergoing bimaxillary orthognathic surgery under hypotensive anesthesia.

Postsurgical Volumetric Airway Changes in Class III Patients Receiving Bimaxillary Orthognathic Surgery.

The purpose of the present study was to investigate the pharyngeal airway space (PAS) changes in class III patients receiving bimaxillary orthognathic surgery and correlate the PAS volume and minimum axial section changes with the magnitude of the surgical movement. This research involved a retrospective sample composed of 38 patients with class III skeletal occlusions. Three-dimensional measurements of the PAS volume and minimum axial section were conducted. Cephalometric points were used to verify the extent of jaw-hyoid bone movement. No significant differences were found between pre and postoperative total PAS volume (P = 0.280), nasopharyngeal volume (P = 0.545), oropharyngeal volume (P = 0.297), and minimum axial section (P = 0.568). Anterior movement of point A and posterior nasal spine were significantly associated with an increase in total PAS volume, oropharyngeal volume, and minimum axial section (P < 0.05). However, the posterior movement of menton was significantly associated with a decrease in total PAS volume, oropharyngeal volume, and minimum axial section (P < 0.05). The results of the present study indicated that PAS is not negatively affected by bimaxillary surgery in class III patients. However, the planning of class III patients who are prone to the development of airway problems should be done carefully.

Correlation between oral cavity volume and upper airway changes in skeletal Class III patients undergoing bimaxillary orthognathic surgery: a pilot cone-beam computed tomography study

ABSTRACT Objectives To evaluate changes of the upper airway and oral cavity volumes in patients with skeletal Class III malocclusion undergoing bimaxillary orthognathic surgery, and to analyze the correlation between postoperative upper airway decrease and the amount of jaw movement and oral cavity volume reduction. Materials and Methods Thirty patients (16 males and 14 females) undergoing bimaxillary surgery were included. Three-dimensional reconstruction of the upper airway and oral cavity were performed using preoperative (T0) and postoperative (T1) (6 months) cone-beam computed tomography scans. Results The volume, sagittal area and minimum cross-sectional area of the upper airway were diminished (P &amp;lt; .001). The decrease in volume and minimum cross-sectional area in the oropharyngeal region of the upper airway were weakly correlated with B-point posterior movement (P &amp;lt; .05). Total oral cavity volume was decreased, with maxillary oral volume increasing and mandibular oral volume decreasing (P &amp;lt; .001). Upper airway decrease was highly correlated with total oral volume reduction and mandibular oral volume reduction, with the most significant correlation being with total oral volume reduction (P &amp;lt; .001). Conclusions Class III bimaxillary surgery reduced the volume, sagittal area, and minimum cross-sectional area of the upper airway as well as oral cavity volume. Upper airway changes were weakly correlated with anterior-posterior mandibular movement but significantly correlated with oral cavity volume changes. Thus, oral cavity volume reduction is a crucial factor of upper airway decrease in patients with skeletal Class III malocclusion undergoing bimaxillary orthognathic surgery.

Need for orthognathic surgery in cleft patients from Northern Finland.

Northern Finland has a unique distribution of clefts compared to the rest of Europe and Finland. This may reflect the need for orthognathic surgery among Northern Finland's patient pool. The aim of this study was to compare previously operated patients aged 18 years or older with cleft lip, cleft lip and alveolus, cleft lip and palate, cleft palate and to evaluate the need for orthognathic surgery in order to achieve a stable and functional occlusion. Materials and methods: The study group consisted of all 18-years-old cleft patients treated in the Oulu Cleft Center. The total amount of patients was 110. The patients were compared retrospectively using patients' hospital records. The majority of patients did not have any cleft-associated syndrome. The need for maxillary or bimaxillary orthognathic or corrective-jaw surgery was evaluated by the Oulu Cleft Team. A descriptive and statistical analysis was used to determine the need for orthognathic surgery according to sex and cleft type. There were nineteen patients of the total of 110 patients who met the criteria requiring corrective-jaw surgery (17,3%). In total 12 males (25,0%) and 7 females (11,3%) were evaluated for the need of orthognathic surgery. Sixteen of the 19 patients had palatal involvement of the cleft. The need for orthognathic surgery was greater in the cleft lip palate and cleft palate patient groups compared to cleft lip alveolus or cleft lip groups. This study also found that males from Northern Finland need surgery more often than females.

The Association of Body Mass Index and Early Outcomes Following Orthognathic Surgery

The existing data on the link between body mass index (BMI), operative characteristics, and surgical outcomes across orthognathic surgery are limited. The purpose was to measure the association between BMI and early postoperative outcomes in orthognathic surgery. This is a retrospective cohort study of patients (n=118) aged > 14years undergoing bimaxillary orthognathic surgery between 2015 and 2018 by a single surgeon within the Kaiser Permanente Northern California-integrated healthcare system. Patients undergoing unilateral or additional procedures, history of prior orthognathic surgery, or pre-existing pain conditions were excluded. The predictor variable was BMI measured as a continuous (kg/m2) and categorical variable (underweight/normal, overweight, obese). The primary outcome variables were additional postoperative antibiotics, increased postoperative visits, wound dehiscence, and wound infection. The secondary outcome variables were total operative and anesthesia time. The demographic covariates included age, sex, and race/ethnicity. The clinical covariates included history of obstructive sleep apnea, Mallampati score, tobacco use, American Society of Anesthesia classification, thyromental distance, history of difficult intubation, and Angle's classification. Bivariate and multivariate analyses were performed to measure the associations between BMI and the primary and secondary outcomes. Multivariable logistic regression analyses were used to measure associations between BMI and the postoperative outcomes. Statistical significance was defined as P<.05. The study sample was composed of 118 subjects with a mean age of 26.91years (standard deviation 9.43). Forty-seven percent (n=55) were male, and the mean BMI was 25.13 (standard deviation 5.19). BMI category was significantly associated with age, with increasing age associated with higher BMI category (P=.02). According to the bivariate and multivariable logistic regression analyses, controlling for age, race/ethnicity, BMI, and total operative time, increased total operative time was associated with additional postoperative antibiotics (odds ratio=1.03, 95% confidence interval: 1.01, 1.05), and increased postoperative appointments (odds ratio=1.02, 95% confidence interval: 1.01, 1.04). No significant association between BMI and other clinical or operative characteristics was seen aside from American Society of Anesthesia classification. Elevated BMI was not associated with worsened operative characteristics or postoperative outcomes. This supports the suitability of orthognathic surgery in a BMI-diverse population.

Does Tranexamic Acid Reduce the Need for Hypotensive Anesthesia Within Orthognathic Surgery? A Retrospective Study.

Tranexamic acid (TXA) is utilized frequently in orthognathic surgery to limit blood loss and improve surgical field visualization. This antifibrinolytic has been proven effective with use of concomitant hypotensive anesthesia. Despite proven efficacy, there is a recent push to avoid perioperative hypotensive anesthesia due to risks of organ hypoperfusion, cardiac ischemia and postoperative nausea. The aim is to study the efficacy and safety of utilizing TXA without controlled hypotensive anesthesia. The authors identified two cohorts of subjects that underwent bimaxillary orthognathic surgery both with and without TXA administration and compared operative and perioperative variables. A retrospective analysis was completed evaluating intraoperative MAP measurements in subjects treated both with and without TXA using descriptive and bivariate analysis. Sixty-three subjects met inclusion criteria. The TXA cohort experienced 11.5% less time under hypotensive anesthesia when compared to the group that did not receive TXA. Additionally, surgical length was decreased by more than 28min when subjects received TXA. No subjects required a blood transfusion or experienced any TXA-related complications. Given the recommendations to limit hypotensive anesthesia perioperatively, TXA is a useful adjunct in orthognathic surgery to limit controlled hypotensive anesthesia.

Reliability of Artificial Intelligence-based Cone Beam Computed Tomography Integration with Digital Dental Images.

This study aimed to introduce cone-beam computed tomography (CBCT) digitization and integration of digital dental images (DDI) based on artificial intelligence (AI)-based registration (ABR) and to evaluate the reliability and reproducibility using this method compared with those of surface-based registration (SBR). This retrospective study consisted of CBCT images and DDI of 17 patients who had undergone computer-aided bimaxillary orthognathic surgery. The digitization of CBCT images and their integration with DDI were repeated using an AI-based program. CBCT images and DDI were integrated using a point-to-point registration. In contrast, with the SBR method, the three landmarks were identified manually on the CBCT and DDI, which were integrated with the iterative closest points method. After two repeated integrations of each method, the three-dimensional coordinate values of the first maxillary molars and central incisors and their differences were obtained. Intraclass coefficient (ICC) testing was performed to evaluate intra-observer reliability with each method's coordinates and compare their reliability between the ABR and SBR. The intra-observer reliability showed significant and almost perfect ICC in each method. There was no significance in the mean difference between the first and second registrations in each ABR and SBR and between both methods; however, their ranges were narrower with ABR than with the SBR method. This study shows that AI-based digitization and integration are reliable and reproducible.

Surgery-first in interdisciplinary class II cases.

To present an interdisciplinary case treated with a surgery-first orthognathic approach, followed by orthodontic and prosthodontic treatment. After an accurate pre-operative virtual planning, a young patient with skeletal class II, retrognathia, and an anterior open bite was treated with bimaxillary orthognathic surgery without pre-surgical orthodontic decompensation. Orthodontic treatment was carried out post-operatively. The treatment was completed with a prosthodontic phase to improve the final esthetic outcome of the smile. A surgery-first approach allowed to achieve esthetic and functional results in a reduced treatment duration that remained stable over the course of 1 year. The outcomes were consistent with prior research in terms of advantages brought by following an accurately planned surgery-first protocol. Nevertheless, longer-term follow-up was required to evaluate the treatment stability. An accurately planned surgery-first approach significantly helped in shortening the duration of the treatment, while providing a stable, functional, and esthetic solution to the patient's problems.

Orthodontic Treatment and Mini Wing Osteotomy: A Case Report of Changes in Facial Aesthetic

For correction of dentofacial deformities, orthosurgical treatment is recommended and often involves bi-maxillary orthognathic surgery. The chin area is an important key for a harmonious facial profile and plays an important role. The present case (of a 38- year-old female) describes one successful surgical-orthodontic treatment. The treatment consisted of the use of an Edgewise fixed appliance (0.022”×0.028”), mini Wing osteotomy (mWo), correction of the deviated nasal septum, and rhinoplasty. The treatment resulted in a better facial harmony and aesthetic with greater definition and lengthening of the submental region, adipose tissue elimination, and an upturned nose due to the correction of the deviated nasal septum associated with rhinoplasty. The Class I canine and molar relationship, the upper and lower midlines coincident with the facial midline, and the compensatory projection of the lower incisors were maintained. A satisfactory overbite and overjet, and leveled curve of Spee were obtained. In conclusion, the orthodontic treatment associated with mWo, correction of the deviated nasal septum, and rhinoplasty surgery provided satisfactory functional and aesthetic results.

Influence of differences in mandibular incisor inclination on skeletal stability after orthognathic surgery in patients with skeletal class III malocclusion

Objective: The preoperative inclination angle of mandibular incisors was crucial for surgical and postoperative stability while the effect of proclined mandibular incisors on skeletal stability has not been investigated. This study aimed to evaluate the effects of differences in presurgical mandibular incisor inclination on skeletal stability after orthognathic surgery in patients with skeletal Class III malocclusion.Methods: A retrospective cohort study of 80 consecutive patients with skeletal Class III malocclusion who underwent bimaxillary orthognathic surgery was conducted. According to incisor mandibular plane angle (IMPA), patients were divided into 3 groups: retroclined inclination (IMPA < 87°), normal inclination (87° ≤ IMPA < 93°) and proclined inclination (IMPA ≥ 93°). Preoperative characteristics, surgical changes and postoperative stability were compared based on lateral cephalograms obtained 1 week before surgery (T0), 1 week after surgery (T1), and at 6 to 12 months postoperatively (T2).Results: The mandible demonstrated a forward and upward relapse in all three groups. No significant differences in skeletal relapse were observed in the 3 groups of patients. However, the proclined inclination group showed a negative overbite tendency postoperatively compared with the other two groups and a clinically significant mandibular relapse pattern. Proclined IMPA both pre- and postoperatively was correlated with mandibular relapse.Conclusion: Sufficient presurgical mandibular incisor decompensation was of crucial importance for the maintenance of skeletal stability in patients with skeletal Class III malocclusion who subsequently underwent orthognathic surgery.

Mandible-First Sequencing Increase Surgical Accuracy for Patients With Skeletal Class II Malocclusion Concomitant With Unstable Condyle-Fossa Relation.

The aim of this study was to explore whether mandible-first sequencing increases the surgical accuracy in bimaxillary orthognathic surgery for patients with skeletal class II malocclusion concomitant with the unstable condyle-fossa relation. A retrospective evaluation of 19 patients who had undergone virtually planned double-splint orthognathic surgery with different operation sequences was performed: maxilla-first (n=9) or mandible-first (n=10) surgery. The centroid position, translational, and rotational differences in the maxilla were evaluated by comparing the virtual plans with actual results. The stability was assessed by comparing the actual results with the follow-up outcomes 6 months postoperatively. The accuracy of the maxilla centroid position was improved in mandible-first sequencing surgery: mandible-first 1.87±0.94mm versus maxilla-first 2.70±0.75mm (P<0.05). Moreover, no significant difference was detected in the translational and orientational discrepancies between the 2 groups. Neither sequencing procedure differed in the overall stability: maxilla-first (1.48±1.13mm) versus mandible-first (1.57±0.90mm). This study indicated that the mandible-first surgery leads to a more accurate maxilla position than the maxilla-first surgery for patients with skeletal class II malocclusion concomitant with the unstable condyle-fossa relation.

Anthropometric and laboratory parameter alterations following bimaxillary orthognathic surgery

The aim of this study was to investigate the impact of bimaxillary orthognathic surgery on patients’ anthropometric measures and laboratory parameters. This study was conducted on patients who underwent bimaxillary orthognathic surgery. Anthropometric measurements were collected before surgery (T0) and at intervals of one week (T1), two weeks (T2), one month (T3), and three months (T4) postoperatively, and laboratory parameters at T0 and T4. Data analysis included repeated-measures ANOVA for assessing weight changes, body mass index (BMI) and fat percentage changes, the Friedman test for muscle mass changes, and independent t tests to understand gender-based differences. Significant reductions were observed in weight (mean differences ranging from 2.26 kg to 3.84 kg, 95.00% CI: 1.29 to 4.62, p < 0.01) and BMI (mean differences ranging from 0.76 to 1.32, 95.00% CI: 0.38 to 1.58, p < 0.01) postoperatively at all follow-up points. Fat percentage changes were significant between T0 – T3 (MD = 1.17, 95.00% CI: 0.26 to 2.08, p < 0.05) and T0 - T4 (MD = 1.28, 95.00% CI: 0.14 to 2.43, p < 0.05). Changes in muscle mass were significant until T3 (MD ranging from 71.00 to 107.0, p < 0.01). Also, haemoglobin levels were significantly higher at T0 than T4 (MD = 0.35, 95% CI: 0 to 0.7). These changes showed no significant gender-based differences (p > 0.05). Our study showed that orthognathic surgery prompts temporary changes in body weight, Body Mass Index, and haemoglobin levels. Future research should explore interventions to mitigate these changes and enhance postoperative recovery.

Successful rehabilitation after multiple severe complications following orthognathic surgery: a case report

BackgroundComplications of orthognathic surgery are quite rare, but they cause suffering in affected individuals. The range of complications is broad and includes both hard and soft tissue.Case presentationWe here present a case of a fully healthy woman without signs of impaired healing capacity. The patient underwent bimaxillary orthognathic surgery and experienced multiple complications both peri- and post-operatively. During the post operative period, the patient also suffered from soft tissue complications after an orthopaedic injury. Therefore, we referred the patient to her general practitioner for further medical investigation. We also present the result after restorative surgery and endodontic and prosthodontic treatment resulting in a successful rehabilitation.ConclusionThis case report clearly shows the need for a good collaboration between different odontological and medical fields to achieve a good and predictable result. In situations where normal healing processes do not occur, in-depth analysis must be carried out.HighlightsOrthognathic surgery affects soft and hard tissue which can result in adverse healing and complications. It is of great importance to follow up performed surgery to see late complications. Be restrictive with early re-operations when there are signs of necrosis. Always use a multidisciplinary approach when handling complications after surgery.

Sequencing in Orthognathic Bimaxillary Surgery: Which Jaw Should Be Operated First? A Scoping Review.

Bimaxillary orthognathic surgery is widely used for the correction of dentoskeletal deformities. Surgery sequencing (maxilla or mandible first) remains debated, and guidelines and consensus are lacking. This scoping review summarizes the state of the art and compares the advantages and disadvantages of both approaches. The review was conducted following PRISMA-ScR guidelines. Three electronic databases (PubMed, Scopus, Web of Science) were searched using the PICO protocol and key words in orthognathic surgical sequencing. Four reviewers screened the records independently, and disagreement was resolved by consensus. A total of 23 records met the inclusion criteria. The advantages and disadvantages of the two approaches were compared and assessed for accuracy of reporting. Within the limitations of the present study, available evidence for the intrinsic advantages and the accuracy of the mandible-first sequence supports the choice of this approach in most cases. Nevertheless, each clinical case needs to be evaluated individually, as no dogmatic recommendations can be given for sequencing in bimaxillary orthognathic surgery.

Correlation between condylar, glenoid fossa and joint space changes two years after bimaxillary orthognathic surgery in class II subjects

The position of the mandible after an orthognathic surgical procedure is believed to be dependent on adaptive condylar and glenoid fossa changes, in addition to condylar positional changes within the fossa. The purpose of this study was to evaluate the association between condylar and glenoid fossa changes and the positional changes in the joint space two years after bimaxillary surgery. The condyles and glenoid fossae were reconstructed from a pair of superimposed pre- and postoperative (two years) cone-beam computerized tomography scans. The surface models were spatially divided into four regions. Three-dimensional morphological and positional changes were measured as volumetric differences and surface distances between the pre- and postoperative condylar and glenoid fossa regions. Statistical associations of condylar, glenoid fossa and joint space changes were calculated by Pearson's correlation coefficient. Twenty subjects (sixteen female; four male; mean age 27.6 years) with class II malocclusion and maxillomandibular retrognathia, who underwent bimaxillary surgery, were assessed. A strong and statistically significant correlation between condylar and glenoid fossa changes was observed two years after surgery (r = 0.52, p < 0.001). The correlation was strongest and statistically significant anterior-medially (r = 0.48, p = 0.002) and anterior-laterally (r = 0.38, p = 0.015). Condylar changes were significantly correlated with the increase in the posterior-medial (r = 0.37, p < 0.020) and the posterior-lateral (r = 0.45, p < 0.003) joint space distances. Changes of the condyle, the glenoid fossa and the joint space following bimaxillary surgery were significantly correlated in these class II subjects.

Condylar Positional Changes in Skeletal Class II and Class III Malocclusions after Bimaxillary Orthognathic Surgery.

Orthognathic surgery is indicated to modify the position of the maxillomandibular structure; changes in the mandibular position after osteotomy can be related to changes in the position of the mandibular condyle in the articular fossa. The aim of this study was to determine changes produced in the mandibular condyle 6 months after orthognathic surgery. A cross-sectional study was conducted that included subjects who had undergone bimaxillary orthognathic surgery to treat dentofacial deformity of Angle class II (group CII) or Angle class III (group CIII). Standardized images were taken using cone-beam computed tomography 21 days before surgery and 6 months after surgery; measurement scales were used to identify the condylar position and its relations with the anterior, superior, and posterior joint spaces. The results were analyzed using the Shapiro-Wilk and Student's t-tests, while considering a value of p < 0.05 as indicating a significant difference. Fifty-two joints from 26 patients, with an average age of 27.9 years (±10.81), were analyzed. All subjects in both group CII and group CIII showed a significant change in the anterior, superior, and posterior joint spaces. However, postoperative changes in the position of the condyle in the articular fossa were not significant in the anteroposterior analysis. We conclude that orthognathic surgery causes changes in the sagittal position of the mandibular condyle in subjects with mandibular retrognathism and prognathism.

Surgical accuracy of CAD/CAM splints using virtual surgical planning in orthognathic surgery: policy implications for healthcare in Australia.

This study examines post-surgical outcomes of maxillary position using virtual surgical planning (VSP) with computer designed and manufactured surgical splints, without the use of costly patient specific implants (PSI), in the treatment of routine nonsyndromic orthognathic patients. The cost of these personalized medical devices and their impact in the setting of cranio-maxillofacial surgery is currently under review by The Department of Health and Aged Care in Australia. This is a single-centre retrospective analysis of 49 patients who underwent bimaxillary orthognathic surgery by a single surgeon at Epworth Richmond Hospital (Victoria, Australia) over a period spanning 2016 to 2020. Patients were included in the study provided their surgery was facilitated using VSP with manufacture of computer designed occlusal splints. Use of computer designed and manufactured splints were highly reliable in reproducing the virtual surgical plan, when using palatal plane, upper incisor angulation, and anterior upper facial height. Use of computer designed and manufactured splints provide a method of leveraging the accuracy of VSP methods, without the additional costs associated with PSI. These findings may assist in appropriate resource allocation and case stratification in patients undergoing orthognathic surgery.

Mandibular reconstruction with TMJ prosthesis: management of osteomyelitis after orthognathic surgery (Case Report).

This case report presents a mandible reconstruction with temporomandibular joint (TMJ) prothesis for treatment of osteomyelitis infection following a bimaxillary orthognathic and genioplasty surgeries. The patient, a 41-year-old female, presented with facial pain, difficulty in opening her mouth, and mandibular deviation four months after the initial orthognathic surgery. During the four months, the patient had experienced two more surgerys post-operative for treatment of the complications. Examination revealed mobility between osteotomy segments of the right mandibular osteotomomie between body and ramus, and Computer Tomographic scan analysis revealed osteomyelitis and non-union within the osteotomy side of the right mandible from the previous surgery. Due to the advanced state of the disease and significant bone resorption, treatment was planned in two stages, involving bone debridement and then reconstruction with a custom made extended temporomandibular joint prosthesis. The patient had no postoperative complications and achieved satisfactory functional and aesthetic outcomes. This case emphasizes the importance of careful monitoring and prompt management of postoperative complications following orthognathic surgery to prevent rare but serious complications such as osteomyelitis.