Changes in Maxillary Sinus Volume and Mucosal Thickness Post Bimaxillary Advancement Procedures: A Retrospective Study.

Background: Bimaxillary surgery is an elemental procedure in the field of cranio-maxillofacial surgery. It allows for the correction of even the most challenging cases of maxillomandibular disorders, malocclusion, facial asymmetry, and disproportion. The osteotomies and maneuvers carried out during the procedure result in changes to the surrounding tissues, including the maxillary sinuses (MS). The aim of this study was to assess the change in the maxillary sinus volume and the thickness of the mucosa after maxillomandibular advancement (MMA) surgeries. Methods: A group of 25 patients who underwent MMA surgery were included in the study. Computed tomography (CT) of the head and neck region was performed 2 weeks preoperatively and 6 months postoperatively. Acquired Digital Imaging and Communications in Medicine (DICOM) files were analyzed using different software programs to calculate the medium MS mucosa thickness and MS volume. Results: A statistically significant reduction in MS volume was observed (p = 0.015). The change in the median thickness of the MS mucosa was not statistically significant. The median sella-nasion-A point angle (SNA angle) value of the group increased from 80.2 to 83.4 degrees. A weak negative correlation between the SNA delta and the MS volume delta was observed. Spearman's rank coefficient: (ρ s = -0.381, p = 0.060). Conclusions: The MMA surgery results in a reduction in the MS volume. The amount of forward movement of the maxilla may be correlated with the extent of the MS volume reduction.

Comparative Analysis of Temperature-Responsive Hydrogel (PF 72) for Postoperative Pain After Bimaxillary Surgery: A Retro-spective Study.

Bimaxillary surgery is a painful invasive procedure in plastic surgery. Pain control is typically achieved using intravenous analgesics. We aimed to investigate the efficacy of a novel temperature-responsive hydrogel, PF72, mixed with ropivacaine, as a local pain management solution when applied directly to the surgical site following orthognathic surgery. The study was conducted from October 2022 to July 2023 and included a cohort of 40 candidates for orthognathic surgery, encompassing LeFort I maxillary ostectomy and sagittal split ramus osteotomy. The participants were divided into an Injection group (n = 20), where PF72 was administered at the surgical site before the orthognathic surgery, and a Control group (n = 20), which relied solely on intravenous analgesics. Pain was evaluated at 3, 6, 24, 48, and 72 h after surgery using a numerical rating scale (NRS). The mean NRS scores at 24 h were 6.35 and 4 for the Control and Injection groups, respectively. The mean NRS scores at 72 h were 3.4 and 2.55 for the Control and Injection groups, respectively. Patients who received PF72 experienced less pain than those who received intravenous analgesics. These findings underscore the potential of PF72 as an effective alternative for enhancing pain management in patients undergoing orthognathic surgery.Level of Evidence III Therapeutic study. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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.

Assessment of soft- and hard-tissue changes following combined anterior segmental bi-jaw orthognathic surgery.

Background: Anterior segmental Bi-jaw orthognathic surgery is indicated primarily for the correction of dentoalveolar protrusion. They are also indicated for correcting apertognathia, closing interproximal spaces between segments and can be incorporated with other osteotomies to obtain better results. Aim: The aim of this study was to analyze and compare the soft- and hard-tissue changes in patients who underwent combined anterior segmental bi-jaw orthognathic surgery. Settings and Design: To compare and evaluate soft- and hard-tissue changes before and after combined anterior segmental bi-jaw orthognathic surgery by assessing (a) parameters in vertical dimension and (b) parameters in horizontal dimension and patient satisfaction was also assessed following surgery at 6 months' time interval. Materials and Methods: It is a prospective, single center and analytical study with sample size of 20 patients. It required routine setup for orthognathic surgery and manual tracing of lateral cephalograms. The surgical outcomes were assessed by hard tissue (Sella Nasion Point A (SNA) angle, Sella Nasion Point B (SNB) angle, Point A Nasion Point B (ANB) angle, NAPg, U1-NF, L1-MP angles; NA, NB, B-Pg, Nasion-Anterior nasal spine (N-ANS) distance, Anterior nasal spine-Gnathion (ANS-Gn) distance, and overjet and overbite) and soft tissue (facial convexity, NL, LM angles; LM fold, UL and LL protrusions, Upper lip length (ULL), Lower lip length (LLL), Sn-A, Si-B, Pg-Pg*, Ls-U1, Li-L1 distances, interlabial gap, and U1 exposure) variables pre and postsurgery. Statistical Analysis: Descriptive statistics involved the mean and standard deviation, and recorded data were subjected to the statistical analysis using IBM SPSS 20 statistical package. The paired t-test, Pearson correlation coefficient were used. The level of significance P < 0.05 was taken as statistically significant and P < 0.01 as very significant. Results: Overall improvement after surgery in both hard- and soft-tissue parameters was observed and significant changes were seen in every variable, except Si-B (P > 0.05). Correlations between soft- and hard-tissue changes were significant in both sagittal and vertical planes. Patients' satisfaction score showed that all patients had the high overall rate of satisfaction. Conclusions: Our study concludes that combined anterior segmental bimaxillary orthognathic surgery is a simple technique with minimal postoperative complications and limited relapse. The changes in facial esthetics and occlusion following orthognathic surgery depend highly on the stability achieved during the postoperative period.

Effect of bimaxillary surgery on the stress distributions in patients with mandibular retrognathia under unilateral molar clenching.

To investigate the effect of bimaxillary surgery on the stress distribution of the temporomandibular joint (TMJ) in patients with mandibular retrognathia under unilateral molar clenching (UMC). Five patients with mandibular retrognathia (preoperative group) and ten asymptomatic subjects (control group) were recruited. In addition, patients treated with bimaxillary surgery were considered as the postoperative group. The muscle forces corresponding to UMC were applied. The results showed that the discal stresses in the postoperative group were significantly greater than those in the preoperative and control groups. Bimaxillary surgery plus UMC had a detrimental effect on the TMJ.

Effects of counterclockwise bimaxillary advancement surgery and relapse on upper airway.

OBJECTIVE: The aim of this study was to evaluate the long-term volumetric changes of the upper airway compartments in response to counterclockwise bimaxillary advancement surgery with multi-piece maxillary osteotomy, and to analyse the relationship between the postoperative stability of the maxillomandibular skeletal complex, and the volumetric airway changes over-time. METHODOLOGY: Twenty-seven sets of pre (T0), post (T1) and follow-up (T2) (20.15 months) CBCT scans were used. The upper airway was isolated into five compartments: soft and bony nasal cavity (SNC, BNC), nasopharynx (NP), oropharynx (OP) and hypopharynx (HP) using Mimics V.22 software. The volumetric changes and the correlation between the airway change and the skeletal movements were analysed using repeated measure ANOVA, and Pearson's correlation coefficient, respectively. RESULTS: The results showed a significant decrease in SNC and BNC (10.94% and 7.69%, p < .05) at T1. However, SNC presented a significant recovery (11.73%, p < .05) at T2. NP, OP and HP segments presented significant and stable increases over time (10.41%, 53.62%, 24.70%, p < .05). CONCLUSIONS: This surgical approach produced a significant increase in OP and HP volumes in short and long term without a significant relapse, NP showed a significant increase in long term only, SNC and BNC volumes showed a significant decrease post-surgery which was only partially maintained for BNC.

Structural and functional changes of nasal cavity and maxillary sinus in patients with skeletal class III malocclusion 1 year after bimaxillary surgery.

PURPOSE: This study aimed to analyse changes in the nasal cavity and maxillary sinus structure and function in patients with skeletal class III malocclusion 1 year after bimaxillary surgery. MATERIALS AND METHODS: In this study, cone-beam computed tomography (CBCT) images of 20 patients (10 men and 10 women; mean age 24.3 ± 3.4 years) with skeletal class III malocclusion who underwent Le Fort I osteotomy and bilateral sagittal split osteotomy were obtained before and 1 year after the surgery. CBCT data were stored opened with element 3D (E3D) to establish a nasal airway model (the paranasal sinus includes only the maxillary sinus). Ansys (ANSYS) software is used for simulation and analysis. RESULTS: The maxillary sinus and nasal cavity volumes decreased significantly 1 year after the surgery. After surgery, the volume of nasal cavity decreased by 13.5%, and the average volume of maxillary sinus decreased by 7.8%. There was no significant difference in the degree of deviation of the septum and nasal cavity resistance, and air distribution in the maxillary sinus did not change. The nasal cavity wall shear stress change was similar to that before surgery. CONCLUSIONS: The maxillary sinus volume and nasal cavity volume of patients with skeletal class III malocclusion changed significantly after bimaxillary surgery, but there was no significant change in nasal ventilation function 1 year after surgery.

Risk Factors for Prolonged Mechanical Ventilation and Delayed Extubation Following Bimaxillary Orthognathic Surgery: A Single-Center Retrospective Cohort Study.

BACKGROUND: Bimaxillary orthognathic surgery bears the risk of severe postoperative airway complications. There are no clear recommendations for immediate postoperative follow-up and monitoring. OBJECTIVE: to identify potential risk factors for prolonged mechanical ventilation and delayed extubation in patients undergoing bimaxillary orthognathic surgery. METHODS: The data of all consecutive patients undergoing bimaxillary surgery between May 2012 and October 2019 were analyzed in a single-center retrospective cohort study. The clinical data were evaluated regarding baseline characteristics and potential factors linked with delayed extubation. RESULTS: A total of 195 patients were included; 54.9% were female, and the median age was 23 years (IQR 5). The median body mass index was 23.1 (IQR 8). Nine patients (4.6%) were of American Society of Anesthesiologists Physical Status Classification System III or higher. The median duration of mechanical ventilation in the intensive care unit was 280 min (IQR, 526 min). Multivariable analysis revealed that premedication with benzodiazepines (odds ratio (OR) 2.60, 95% confidence interval (0.99; 6.81)), the male sex (OR 2.43, 95% confidence interval (1.10; 5.36)), and the duration of surgery (OR 1.54, 95% confidence interval (1.07; 2.23)) were associated with prolonged mechanical ventilation. By contrast, total intravenous anesthesia was associated with shorter ventilation time (OR 0.19, 95% confidence interval (0.09; 0.43)). CONCLUSION: premedication with benzodiazepines, the male sex, and the duration of surgery might be considered to be independent risk factors for delayed extubation in patients undergoing bimaxillary surgery.

Fully Digitalized Workflow for One-Stage Mandibular Contouring and Orthognathic Surgery to Correct Severe Facial Asymmetry.

INTRODUCTION: Surgical correction of facial asymmetry is commonly performed in at least two stages. Recently, because of the long duration of a two-step procedure, the demand for a one-step procedure has increased. Our study aims to present a fully digitalized workflow for one-stage mandibular contouring (MC) and bimaxillary surgery to correct severe facial asymmetry using 3D technology. MATERIALS AND METHODS: A retrospective monocentric study was conducted for all patients affected by severe facial asymmetry who had undergone MC and orthognathic surgery between January 2018 and June 2020 at the Face Surgery Center, in Parma, Italy. RESULTS: The final study sample included 20 patients (12 women and 8 men). The mean age of the patients at the time of surgery was 20.8 years (range: 18-25 years). At the one-year follow-up, all patients had stable occlusion with a symmetric face. Mandibular angle degree (Ar-Go-Me) increased significantly from 113. 6° to 122.7° at the left side and from 113.3° to 122.7° at the right side (p < 0.05) (Table 1). The mandibular width (Go-Go) decreased from 116.5 to 106.4 mm (p < 0.05). CONCLUSION: A fully digitalized workflow for one-stage MC and bimaxillary surgery is a safe and valid option to correct facial asymmetry. CAD CAM technology is an indispensable tool to obtain predictable results. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Changes in the pharyngeal airway after different orthognathic procedures for correction of class III dysplasia.

OBJECTIVE: This study was conducted to compare changes in pharyngeal airway after different orthognathic procedures in subjects with class III deformity. METHODS: The study included CBCT scans of 48 skeletal class III patients (29 females and 19 males, mean age 23.50 years) who underwent orthognathic surgery in conjunction with orthodontic treatment. The participants were divided into three groups of 16, as follows: Group 1, mandibular setback surgery; group 2, combined mandibular setback and maxillary advancement surgery; and group 3, maxillary advancement surgery. CBCT images were taken 1 day before surgery (T0), 1 day (T1), and 6 months (T2) later. The dimensions of the velopharynx, oropharynx, and hypopharynx were measured in CBCT images. RESULTS: In all groups, there was a significant decrease in airway variables immediately after surgery, with a significant reversal 6 months later (P < 0.05). In subjects who underwent maxillary advancement, the airway dimensions were significantly greater at T2 than the T0 time point (P < 0.05), whereas in the mandibular setback and bimaxillary surgery groups, the T2 values were lower than the baseline examination (P < 0.05). The alterations in airway variables were significantly different between the study groups (P < 0.05). CONCLUSIONS: The mandibular setback procedure caused the greatest reduction in the pharyngeal airway, followed by the bimaxillary surgery and maxillary advancement groups, with the latter exhibiting an actual increase in the pharyngeal airway dimensions. It is recommended to prefer a two-jaw operation instead of a mandibular setback alone for correction of the prognathic mandible in subjects with predisposing factors to the development of sleep-disordered breathing.

A clinico-statistical study of factors associated with intraoperative bleeding in orthognathic surgery.

BACKGROUND: Excessive bleeding is a major intraoperative risk associated with orthognathic surgery. This study aimed to investigate the factors involved in massive bleeding during orthognathic surgeries so that safe surgeries can be performed. Patients (n=213) diagnosed with jaw deformities and treated with bimaxillary orthognathic surgery (Le Fort I osteotomy and bilateral sagittal split ramus osteotomy) in the Department of Oral and Maxillofacial Surgery at the Suidobashi Hospital, Tokyo Dental College between January 2014 and December 2016 were included. Using the patients' medical and operative records, the number of cases according to sex, age at the time of surgery, body mass index (BMI), circulating blood volume, diagnosis of maxillary deformity, direction of maxillary movement, operative duration, incidence of bad split, injury of nasal mucosa, and blood type were analyzed. RESULTS: The results revealed that BMI, circulating blood volume, nasal mucosal injury, and operative time were associated with the risk of intraoperative massive bleeding in orthognathic surgeries. Chi-square tests and binomial logistic regression analyses showed significant differences in BMI, circulating blood volume, direction of maxillary movement, operative duration, and injury to the nasal mucosa. Operative duration emerged as the most important risk factor. Furthermore, a >4-mm upward migration of the posterior nasal spine predicted the risk of massive bleeding in orthognathic surgery. CONCLUSIONS: The upward movement of the maxilla should be recognized during the preoperative planning stage as a risk factor for intraoperative bleeding, and avoiding damage to the nasal mucosa should be considered a requirement for surgeons to prevent massive bleeding during surgery.

Comparison of stability and outcomes of surgery-first bimaxillary surgery for skeletal class III deformity between unilateral and bilateral cleft lip and palate.

OBJECTIVES: Some adults with cleft lip and palate (CLP) require orthognathic surgery due to skeletal deformity. This prospective study aimed to (1) compare skeletal stability following bimaxillary surgery for correction of class III deformity between patients with unilateral CLP (UCLP) and bilateral CLP (BCLP), and (2) identify risk factors of stability. MATERIALS AND METHODS: Adults with CLP and skeletal class III deformities who underwent surgery-first bimaxillary surgery were divided into two groups according to cleft type: UCLP (n = 30) and BCLP (n = 30). Skeletal stability was assessed with measures from cone beam computed tomography images of the maxilla and mandible taken before treatment, 1-week and ≥ 1 year postsurgery for translation (left/right, posterior/anterior, superior/inferior) and rotation (yaw, roll, pitch); multiple regression analysis examined risk factors. RESULTS: At follow-up, the maxilla moved upwards in both groups, and backwards in the UCLP group. The mandible moved forward and upward, shifted to the cleft (deviated) side, and rotated upward in both groups. The amount of surgical advancement was a risk factor for sagittal stability in the maxilla (ß = -0.14, p < 0.05). The mandible had three risk factors for sagittal stability: age (ß = -0.23, p < 0.05), surgical team (ß = -1.83, p < 0.05), and amount of surgical setback (ß = -0.32, p = 0.001). CONCLUSIONS: Two years after bimaxillary surgery, patients with UCLP had a higher sagittal relapse of the maxilla compared with patients with BCLP, which was due to a greater surgical advancement in the patients with UCLP. CLINICAL RELEVANCE: Surgery-first bimaxillary surgery results in favorable treatment outcomes for correction of cleft-related class III deformity. Severity of jaw discrepancy and surgeons should be considered in the surgical design of overcorrection.

Penehyclidine for prevention of postoperative nausea and vomiting following bimaxillary orthognathic surgery: a randomized, double-blind, controlled trial.

PURPOSE: To investigate the efficacy and safety of low-dose bolus plus continuous infusion of penehyclidine in preventing postoperative nausea and vomiting (PONV) following bimaxillary surgery. METHODS: Three hundred fifty-four patients were randomly allocated into three groups. In the Control group, placebo (normal saline) was injected before anesthesia and infused over 48 h after surgery; in the Bolus group, 0.5 mg penehyclidine was injected before anesthesia, whereas placebo was infused after surgery; in the Infusion group, 0.25 mg penehyclidine were injected before anesthesia, another 0.25 mg penehyclidine was infused after surgery. The primary endpoint was the incidence of PONV within 72 h. RESULTS: A total of 353 patients were included in intention-to-treat analysis. The PONV incidence was 61.0% (72/118) in the Control group, 40.2% (47/117) in the Bolus group, and 28.0% (33/118) in the Infusion group. The incidence was significantly lower in the Bolus group than in the Control group (RR 0.66; 95% CI 0.51-0.86; adjusted P = 0.003) and in the Infusion group than in the Control group (RR 0.46; 95% CI 0.33-0.63; adjusted P < 0.001); the difference between the Infusion and Bolus groups was not statistically significant (RR 0.70; 95% CI 0.48-1.00; adjusted P = 0.144). Emergence agitation occurred more frequently in the Bolus group than in the Control group (36.8% [43/117] vs. 21.2% [25/118], adjusted P = 0.027), but did not differ significantly between the Infusion and Control groups. CONCLUSIONS: A low-dose bolus plus continuous infusion of penehyclidine was effective in preventing PONV without increasing emergence agitation. TRIAL REGISTRATION: Clinicaltrials.gov. Identifier: NCT04454866.

Comparison of oropharyngeal airway dimensional changes in patients with skeletal Class II and Class III malocclusions after orthognathic surgery and functional appliance treatment: A systematic review.

OBJECTIVE: To compare the dimensional changes in the oropharyngeal airway in patients with skeletal Class II and Class III malocclusion before and after orthognathic surgery and treatment with a functional appliance. METHODS: The protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) and was registered to the International Prospective Register of Systematic Reviews (PROSPERO) under the registration number CRD42020170901. Furthermore, the reporting of the present SR was performed based on the PRISMA checklist. RESULTS: The use of removable functional appliances increased the volume of the oropharyngeal airway in patients with skeletal Class II malocclusion. Furthermore, the increase in the volume of the oropharyngeal airway following the removable functional appliance treatment was more than that observed after fixed functional appliance treatment in growing patients. For patients with skeletal Class III malocclusion, who underwent the bimaxillary orthognathic surgery, resulted in no change in the dimensions of the oropharyngeal airway. CONCLUSION: Growing patients who receive removable functional appliance treatment have a more favorable long-term prognosis with regard to the oropharyngeal airway when compared with those who receive fixed functional appliance. Alternatively, in patients aged from (18-22) years with skeletal class III malocclusion Bimaxillary orthognathic surgery was found to be the recomended and superior method of treatment.

Relapse and temporomandibular joint dysfunction (TMD) as postoperative complication in skeletal class III patients undergoing bimaxillary orthognathic surgery: A systematic review.

OBJECTIVES: The aim of this study was to determine Relapse and TMD as postoperative complication in skeletal class III patients undergoing bimaxillary orthognathic surgery. MATERIALS AND METHODS: Data was obtained by database searching using The Cochrane Central Register of Controlled Trials (central), PUBMED, SCOPUS, EMBASE, Google scholar, National Medical library, New Delhi. The titles and abstracts of the electronic search results were screened and evaluated by two observers for eligibility according to the inclusion and exclusion criteria. RESULTS: 5261 articles were retrieved for the review. Among these, 3474 duplicate articles were removed. 418 studies were selected based on the eligibility criteria. For the present review, 30 articles were included after elimination according to the inclusion criteria. The Prisma diagram flowchart demonstrates our selection scheme. Quality assessment criteria to evaluate the studies were decided by two review authors in accordance with CONSORT guidelines. Each study was assessed using the evaluation method described in the Cochrane Handbook for Systematic Reviews. Among the 30 studies included in the review, marked degree of relapse in the mandible was noted from 3 months - 1 year postoperatively in 8 studies, 5 studies reported both TMD prevalence and relapse, whereas only 4 studies reported TMD disorder alone. CONCLUSION: Complications of relapse and TMD are associated with bimaxillary orthognathic surgery procedures. More RCTs and CCTs are needed in this regard to get better quality evidence. This review was registered with PROSPERO: CRD42020211342.

Postoperative changes in the pharyngeal airway space through computed tomography evaluation after mandibular setback surgery in skeletal class III patients: 1-year follow-up.

BACKGROUND: This study evaluated the pharyngeal airway space changes up to 1 year after bilateral sagittal split osteotomy mandibular setback surgery and bimaxillary surgery with maxillary posterior impaction through three-dimensional computed tomography analysis. METHODS: A total of 37 patients diagnosed with skeletal class III malocclusion underwent bilateral sagittal split osteotomy setback surgery only (group 1, n = 23) or bimaxillary surgery with posterior impaction (group 2, n = 14). Cone-beam computed tomography scans were taken before surgery (T0), 2 months after surgery (T1), 6 months after surgery (T2), and 1 year after surgery (T3). The nasopharynx (Nph), oropharynx (Oph), hypopharynx (Hph) volume, and anteroposterior distance were measured through the InVivo Dental Application version 5. RESULTS: In group 1, Oph AP, Oph volume, Hph volume, and whole pharynx volume were significantly decreased after the surgery (T1) and maintained. In group 2, Oph volume and whole pharynx volume were decreased (T2) and relapsed at 1 year postoperatively (T3). CONCLUSION: In class III malocclusion patients, mandibular setback surgery only showed a greater reduction in pharyngeal airway than bimaxillary surgery at 1 year postoperatively, and bimaxillary surgery was more stable in terms of airway. Therefore, it is important to evaluate the airway before surgery and include it in the surgical plan.

Is there a hidden blood loss in orthognathic surgery and should it be considered? Results of a prospective cohort study.

The aim of this prospective observational study was to investigate the parameter 'hidden blood loss' (HBL) in the context of orthognathic surgery, incorporating undetected bleeding volumes occurring intra- and postoperatively. Orthognathic bleeding volumes were recorded at three different time points. At the end of the operation the visible intraoperative blood loss (VBL) was measured. Additionally, the perioperative blood loss was calculated 24 h and 48 h postoperatively using the 'haemoglobin balance method'. Analysis of the HBL was based on the difference between the visible intraoperative blood loss (VBL) and calculated blood loss (CBL), determined 48 h after surgery. 82 patients (male 33, female 49) were included in this study, of whom 41 underwent bimaxillary surgery and of whom 41 underwent Bilateral Sagittal Split Osteotomy (BSSO). Statistically significant differences with reference to the absolute bleeding volumes were found when comparing the two treatment modalities. In terms of HBL, a bleeding volume of 287.2 ml (±265.9) in the bimaxillary group and 346.9 ml (±271.3) in the BSSO cohort was recorded. This accounted for 32.2% (bimaxillary surgery) and 62.6% (BSSO) of the CBL after 48 h (BIMAX vs. BSSO, p < 0.001). HBL is a valuable adjunct to record within the perioperative management of orthognathic surgery to further improve patient safety and postoperative outcomes.

A rare complication of an Arteriovenous shunt after bimaxillary surgery.

The most common complications following bimaxillary surgery are inferior alveolar nerve damage, hemorrhage, and relapse. Severe complications are rare, but few cases of vascular arteriovenous malformation, cavernous sinus thrombosis, formation of an aneurysm or arteriovenous shunting are reported in literature. We present a case of a 20-year-old male patient who developed a right sided tinnitus and visible pulsations close to the mandibular angle on the right side after bimaxillary surgery. CT-angiography and subsequent digital subtraction angiography (DSA) six months after surgery showed an arteriovenous fistula (AVF) from the external carotid artery to the external jugular vein. The AVF was treated by endovascular coil embolization. At six months after intervention there were no residual complaints. We discuss the possible etiology and trauma mechanisms that might have caused this pathology and present recommendations to avoid this type of complications.

Drug-Induced Sleep Endoscopy Upper Airway Collapse Patterns and Maxillomandibular Advancement.

OBJECTIVES/HYPOTHESIS: To evaluate upper airway (UA) collapse patterns during drug-induced sleep endoscopy (DISE) and maxillomandibular advancement (MMA) surgery outcome, paying particular attention to the DISE phenotype complete concentric collapse at the level of the palate (CCCp). STUDY DESIGN: Prospective case series. METHODS: Nineteen patients diagnosed with obstructive sleep apnea (OSA) prospectively underwent mandibular advancement device (MAD) treatment followed by MMA surgery. UA collapse patterns were evaluated before and after MMA surgery. Baseline apnea-hypopnea index (AHI) was compared with AHI during MAD treatment and after MMA surgery. UA collapse patterns and the presence of baseline CCCp were assessed. AHI differences between patients with and without CCCp after MMA surgery were compared. RESULTS: In 14 patients, a full dataset was obtained: 8/6 (male/female), mean age = 51 ± 7 years, body mass index (BMI) = 25.6 ± 3.7 kg/m2 , and baseline AHI = 40.2 ± 25.6 per hour of sleep. MMA surgery reduced AHI to 9.9 ± 7.2 per hour of sleep (P = .0001). Eight patients benefited from additional AHI reduction compared to MAD treatment (P = .0113). Six out of 14 (43%) patients showed baseline CCCp. Baseline patient characteristics (age, BMI, and AHI) did not significantly differ between patients with and without CCCp. AHI was equally reduced after MMA, whether (P = .0145) or not (P = .0075) CCCp was present at baseline. All patients showed resolution of CCCp (P = .0159) during postoperative DISE. CONCLUSIONS: CCCp seems not to be a negative predictor for MMA surgery outcome measured by AHI reduction. Furthermore, MMA is likely to eliminate CCCp. Therefore, MMA might be a solution for OSA patients showing CCCp and broadens the perspective for personalized medicine and combination therapy. However, a large sample is required for definitive results. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E268-E274, 2020.

Surgical correction of dentofacial deformities in juvenile idiopathic arthritis: a systematic literature review.

The aim of this study was to assess current evidence for the surgical correction of dentofacial deformities in patients with temporomandibular joint (TMJ) involvement from juvenile idiopathic arthritis (JIA). A systematic literature review, according to the PRISMA guidelines, was conducted. Meta-analyses, randomized controlled trials, cohort studies, observational studies, and case reports were eligible for inclusion. Exclusion criteria were no JIA diagnosis, no clearly defined outcomes, dual publications (except meta-analyses), non peer-reviewed studies, non English language publications, and animal studies. The outcome measures assessed were TMJ function, skeletal alignment, and morbidity. The database search identified 255 citations, of which 28 met the eligibility criteria. Of these, 24 were case reports or case series with a low level of evidence that did not allow for meta-analysis. Extrapolated evidence supports orthognathic surgery in skeletally mature patients with controlled or quiescent JIA and a stable dentofacial deformity. Distraction osteogenesis was recommended for severe deformities. Some authors demonstrated unpredictable postoperative mandibular growth with costochondral grafts. Alloplastic TMJ reconstruction was efficacious, but should be used cautiously in skeletally immature patients. TMJ function and skeletal alignment was improved with reconstruction by any technique and morbidity was low. The surgical correction of arthritis-induced dentofacial deformities is indicated but the level of evidence is low. Prospective multicenter studies are needed.