Bimaxillary Advancement Research Articles

The Use of Bone Substitute Blocks in Minimally Invasive Orthognathic Surgery: Enhancing Jaw Stability and Healing.

This study aims to evaluate the use of bone substitute blocks (BSBs) in minimally invasive orthognathic surgery for the maxilla, mandible, and chin, highlighting their impact on jaw stability and bone healing. A retrospective analysis was conducted on 47 consecutive patients (33 females, 14 males; mean age: 27y) who underwent bimaxillary advancement surgery. Procedures employed the minimally invasive orthognathic surgery approach. Bovine BSBs (Bio-Oss Collagen) were used to fill gaps in all cases. Postoperative follow-up included computed tomography scans at immediate and 1-year intervals. All patients achieved the desired clinical outcomes without complications such as wound dehiscence, infection, or nonunion. Visual Analog Scale scores indicated high levels of bone formation, with mean scores of 9.1 in the chin, 8.5 in the maxilla, and 7.9 in the mandible. The study supports the routine use of BSBs in orthognathic surgeries, though further research is needed to validate these findings and explore long-term outcomes.

Evaluation of Minimum Axial Airway Area and Airway Volume in Orthognathic Surgery Patients.

The aim of this study was to compare preoperative and postoperative linear, planar, and volumetric measurements in the pharyngeal airway in orthognathic surgery patients. Preoperative and postoperative cone beam computed tomography (CBCT) images of 60 patients, who underwent maxillary advancement with mandibular setback (Group I, n=25) and bimaxillary advancement (Group II, n=35), were compared. The airway was divided into 3 regions as nasopharynx, oropharynx, and hypopharynx. Linear and planar measurements were made on the reference sections of each region. The minimum axial airway area, the volume of 3 regions, and total airway volume were also measured. Regarding the linear, planar, and volumetric measurements, while there was a statistically significant increase in the measurements for all three regions in Group II, in Group I only the measurements in the nasopharyngeal region demonstrated a statistically significant increase postoperatively ( P <0.05). There was an increase in minimum axial airway areas in both groups; however, it was only statistically significant in Group II ( P <0.05). There was a statistically significant increase in total airway volumes in both groups ( P <0.05). A positive and good correlation was found between the percent increase in the minimum axial area and the percent increase in the total volume ( P <0.05). While bimaxillary advancement surgery results in a significant increase in the pharyngeal airway, mandibular setback with maxillary advancement caused an increase in the total airway. Changes that may occur in the airway should be considered while planning orthognathic surgery.

The Assessment of Upper Airway Volume Changes Following Bimaxillary Advancement Surgery: A Radiological Evaluation in the Supine Position at Multiple Intervals.

Background: Bimaxillary surgeries (BiMax) are an essential part of the craniomaxillofacial specialty. The osteotomies and subsequent spatial rearrangement of the maxilla and the mandible enable the correction of facial deformities, asymmetry, and malocclusion. Moreover, the movements performed during the procedure affect the morphology of surrounding soft tissues, including the upper airway (UA). Objectives: The objective of this study was to radiologically assess the potential volumetric alterations of the UA in the supine position at various intervals following BiMax advancement surgeries. Methods: A group of 31 patients who underwent BiMax advancement surgery were included in the study. Medical computed tomography (CT) of the head and neck region was performed 2 weeks preoperatively, 1 day postoperatively, and 6 months postoperatively. The UA volumes were calculated and analyzed based on the acquired Digital Imaging and Communications in Medicine (DICOM) files using different software applications. The sella-nasion-A point (SNA) and sella-nasion-B point (SNB) angles were evaluated to measure the achieved maxillomandibular advancement. Results: When comparing the volume of the UA before surgery, post-surgery, and 6 months post-surgery, the p-value was <0.001, indicating statistically significant differences in UA volume between the successive examinations. A statistically significant difference was found between UA volume before surgery and 6 months post-surgery and between UA volume after surgery and 6 months post-surgery, with the obtained p-values being <0.001 and 0.001, respectively. A significantly larger UA volume was observed 6 months post-surgery (mean ± SD: 27.3 ± 7.3) compared to the volume before surgery (mean ± SD: 22.2 ± 6.4), as well as 6 months post-surgery compared to the volume assessed shortly after surgery (mean ± SD: 24.2 ± 7.3). Conclusions: BiMax advancement surgeries result in the significant enlargement of the UA. The volume of the UA does not diminish immediately following the procedure and is not constant; it increases significantly during the postoperative observation period.

Major clinical results of orthognatic surgery in obstructive sleep apnea syndrome: a systematic review

Introduction: Obstructive sleep apnea involves obstruction or narrowing of an individual's airways during sleep and is associated with several comorbidities. Management can be surgical or non-surgical, and Phase II of the Stanford Protocol for surgical management involves maxillomandibular advancement. Objective: To conduct a concise systematic review to present the main considerations and clinical results of orthognathic surgery in obstructive sleep apnea syndrome. Methods: The PRISMA Platform systematic review rules were followed. The search was carried out from April to June 2024 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: 110 articles were found, 41 articles were evaluated and 23 were included in this systematic review. Considering the Cochrane tool for risk of bias, the global assessment resulted in 28 studies with a high risk of bias and 28 studies that did not meet GRADE. Most studies showed homogeneity in their results, with X2 =88.5% &gt;50%. Maxillomandibular advancement surgery is a successful treatment for obstructive sleep apnea, but there are still concerns about cosmetic results due to the major advances involved. Bimaxillary advancement osteotomy significantly increases oropharyngeal volume and contracted superficial areas, which remain stable between 6 months and 1 year postoperatively.

Clinical results of orthognatic surgery in the treatment of obstructive sleep apnea syndrome: a systematic review

Introduction: Obstructive sleep apnea syndrome (OSAS) is characterized by intermittent partial or complete obstruction of the airways during sleep and is called OSAS syndrome when associated with day/night symptoms and/or comorbidities, such as systemic arterial hypertension or diabetes mellitus. The prevalence reaches 32% in the general population, varies between 1% and 20% when associated with COPD (overlap syndrome), and is described as above 60% in populations with COPD and obesity. Orthognathic surgery (OC) can correct deformities of the maxillary and mandibular bones in OSAS. Objective: It was to develop the main approaches and clinical results of orthognathic surgery for the treatment of obstructive sleep apnea syndrome through a systematic review. Methods: The PRISMA Platform systematic review rules were followed. The search was carried out from November 2023 to February 2024 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: 146 articles were found, 58 articles were evaluated and 26 were included in this systematic review. Considering the Cochrane tool for risk of bias, the global assessment resulted in 32 studies with a high risk of bias and 22 studies that did not meet GRADE. Most studies showed homogeneity in their results, with X2 =65.8%&gt;50%. Maxillomandibular advancement surgery is a successful treatment for obstructive sleep apnea, but there are still concerns about cosmetic results due to the major advances involved. Bimaxillary advancement osteotomy significantly increases oropharyngeal volume and contracted superficial areas, which remain stable between 6 months and 1 year postoperatively.

P127 Challenges of surgery only bimaxillary advancement for the management of obstructive sleep apnoea

P127 Challenges of surgery only bimaxillary advancement for the management of obstructive sleep apnoea

Nasal and maxillary sinus volume change in patients with obstructive sleep apnea after bimaxillary advancement surgery

The airway complex is modified by bimaxillary advancement surgery performed in patients suffering from obstructive sleep apnea (OSA). The aim of the present study is to analyse the volume of nasal and maxillary sinus after bimaxillary advancement surgery in patients suffering from OSA. The maxillary sinus and nasal complex of eighteen patients with OSA was measured through cone-beam computed tomography (CBCT) before and after they were treated with bimaxillary advancement surgery. Digital planning software was used to effectively measure the upper volume changes, as well as, statistical analysis of the results was performed.Methods Eighteen patients were diagnosed with OSA the severity of which was measured by the apnea hypopnea index and were selected and submitted to preoperative and postoperative CBCT scans. Afterwards, datasets were uploaded into therapeutic digital planning software (Dolphin Imaging) to measure the volume of the right and left maxillary sinus and nasal and maxillary sinus complex. Statistically analysis between preoperative and postoperative measures was performed by Student t-test statistical analysis.Results The paired t-test showed statistically significant volumetric reductions in the left maxillary sinus (p = 0.0004), right maxillary sinus (p < 0.0001) and nasal and maxillary sinus complex (p = 0.0009) after bimaxillary advancement surgery performed in patients suffering from OSA.Conclusion The results showed that bimaxillary advancement surgery reduces the maxillary sinus volume as well as, the fossa nasal and sinus complex volume.

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

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. 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. 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). 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.

Major clinical results of orthognathic surgery and maxillomandibular advancement in obstructive sleep apnea syndrome

Introduction: Obstructive sleep apnea involves obstruction or narrowing of an individual's airway during sleep and is associated with several comorbidities. Management can be surgical or nonsurgical, and Phase II of the Stanford Protocol for surgical management involves maxillomandibular advancement. Objective: It was to carry out a concise systematic review to present the main considerations and clinical results of orthognathic surgery in obstructive sleep apnea syndrome. Methods: The systematic review rules of the PRISMA Platform were followed. The research was carried out from September to November 2022 in Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 270 articles were found, 47 articles were evaluated and 23 were included in this systematic review. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 35 studies at high risk of bias and 125 studies that did not meet the GRADE. Most studies showed homogeneity in their results, with I2 =95.9% &gt;50%. Maxillomandibular advancement surgery is a successful treatment for obstructive sleep apnea, but there are still concerns about the aesthetic results due to the great advances involved. The bimaxillary advancement osteotomy significantly increases the oropharyngeal volume and constricted surface areas, which remains stable between 6 months to 1 year postoperatively.

Schlafmedizin für den Hals-Nasen-Ohren-Facharzt

Sleep-related breathing disorders can be divided into obstructive and central sleep apnea, and hypoventilation syndromes. The diagnosis is made according to an algorithm in which clinical symptoms and a polygraphy or polysomnography usually point the way. After initial diagnosis of the most common obstructive sleep apnea, conservative therapies such as positive airway pressure therapy (PAP therapy), positional therapy, and/or mandibular advancement splint are used in many cases, supplemented by treatment of risk factors. If PAP therapy is not possible, more detailed diagnosis of airway obstruction, often with sleep videoendoscopy, is required. In general, "muscle-sparing" surgical techniques such as tonsillectomy with uvulapalatopharyngoplasty (TE-UPPP) should be considered whenever possible. This is especially important in the surgical treatment of snoring. More surgical therapy alternatives are for example barbed wire pharyngoplasty, tongue pacemaker and bimaxillary advancement. Optimal therapy alternatives should be evaluated in a sleep medicine center.

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

ObjectiveThis study was conducted to compare changes in pharyngeal airway after different orthognathic procedures in subjects with class III deformity.MethodsThe 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.ResultsIn 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).ConclusionsThe 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.

Efficiency of maxillomandibular advancement for the treatment of obstructive apnea syndrome: a comprehensive overview of systematic reviews.

To evaluate the efficiency of maxillomandibular advancement using aggregated individual patient data from multiple studies. This overview was structured according to the PICO strategy. It adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses checklist and was recorded on the international prospective register of systematic reviews (PROSPERO-CRD42020206135). Searches were conducted in the PubMed/MEDLINE, Scopus, Embase, Web of Science, LILACS, and Cochrane databases for studies published until January 1, 2021. Data from the included studies were collected by one author, while another reviewed the compilation. Twelve systematic reviews were included. The outcome measures studied were the apnea-hypopnea index, respiratory disturbance index, mean oxygen saturation, lowest oxygen saturation, sleepiness data, posterior air space, sella-nasion point A angle, sella-nasion point B angle, surgical success, and surgical cure in patients who underwent surgery. The AMSTAR scale presented moderate evaluations, with grades varying between 6 and 10 points. The Glenny scale revealed that the study selection did not include all languages. Only three reviews identified quality assessments conducted by at least two reviewers and only five related possible searches for unpublished data. Bimaxillary advancement surgery improved respiratory indicators, sleepiness data, and increased upper airway size. However, it is necessary to standardize the surgical criteria to establish measurable efficiency of the procedure. This overview makes a critical analysis of the results of the selected systematic reviews with the aim of presenting the most clinically relevant data on the maxillomandibular advancement for treating obstructive apnea syndrome, with a focus on improving respiratory, anatomical, and quality of life indices. There are no overviews that approach this theme from a well-structured perspective.

Long-term three-dimensional effects of orthognathic surgery on the pharyngeal airways: a prospective study in 128 healthy patients.

To investigate volumetric and circumferential pharyngeal airway space (PAS) changes and stability over time as evaluated with cone beam computed tomography (CBCT) before and after orthognathic surgery 2years postoperatively. One hundred twenty-eight patients underwent bimaxillary orthognathic surgery at the Department of Maxillofacial Surgery of University Hospitals, Leuven, Belgium, were recruited prospectively. Patients were divided into 4 groups based on the amount of mandibular advancement in 5mm increments (< 0mm, 0-5mm, 5-10mm, or > 10mm). CBCT data was acquired preoperatively and 1-6weeks, 6months, 1year, and 2years postoperatively. Patients with a history of maxillofacial trauma or surgery, obstructive sleep apnoea syndrome, or craniofacial anomalies were excluded. Nasopharyngeal, oropharyngeal, and hypopharyngeal PAS volumes and constriction surface areas (mCSA) were measured and compared between each time point with a paired t-test. The largest significant increase in oropharyngeal volume and mCSA were observed in the 5-10mm (+ 13.3-21.7%, + 51.3-83.0%)) and > 10mm (+ 23.3-44.6%, + 92.3-130.0%) mandibular advancement groups. This increase only remained stable 2years postoperatively in the > 10mm group. In other mandibular advancement groups, short-term oropharyngeal volume and mCSA increases were noticed, which returned to baseline levels 6months to 1year postoperatively. Bimaxillary advancement osteotomy significantly increases oropharyngeal volume and mCSA, which remains stable between 6months to 1year postoperatively. Long-term stable volumetric and mCSA enlargements were found with > 10mm mandibular advancements over a period of 2years. Return towards baseline levels was observed in the other mandibular advancement groups.

Advanced Facial Rejuvenation After Bimaxillary Surgery in Three Different Facial Types.

Facial aging is the consequence of many mechanisms involving the bones and the "soft tissue" (skin, fat, ligaments, muscles, and periosteum) of the face such as downward migration of the soft tissue, adipose and muscular tissue atrophy, and skeletal resorption. The potential of orthognathic surgery (double jaw surgical advancement) of expanding the skeletal foundation to increase the facial drape support is now recognized and widely popularized by several authors. The aim of this study was to analyze the rejuvenation change of the face after bimaxillary advancement for orthognathic surgery, focusing on the previously mentioned stigmata of the middle and the lower third of the aging face. A retrospective monocentric chart review was conducted for all patients affected by aging signs of the face who underwent orthognathic surgery between January 2015 and December 2019 at the Face Surgery Center (Parma, Italy). During the postoperative follow-up examination, all patients underwent anthropometric photographs and esthetic assessment to evaluate facial rejuvenation after double jaw surgical advancement. After application of the exclusion criteria, the final study sample included 85 patients (53 females, 32 males). Eighty-three patients (97%) showed a degree of rejuvenation after maxillo-mandibular advancement (MMA); the score of the postoperative face was less than the score of the preoperative face. Two patients reported no significant postoperative change; none reported a more aging face, with a successful "reverse face-lift" occurred in 97% of our cases. "Reverse face-lift" by bimaxillary advancement is a surgical procedure which is indicated for a selected group of middle-aged patients with a diagnosis of bimaxillary skeletal retrusion or posterior divergence very motivated to an extreme rejuvenation; this procedure provides support for the facial mask resulting in whole facial rejuvenation.

Three-dimensional pharyngeal airway space changes after bimaxillary advancement.

ABSTRACTIntroduction: The probability of improvement in the upper airway space (UAS) with orthognathic surgery should be considered during the surgical-orthodontic treatment decision, providing not only an esthetic, but also a functional benefit for the patient. Objective: The purpose of this study was to evaluate the 3D changes in the upper airway space after maxillomandibular advancement surgery (MMA). Methods: A retrospective analysis of 56 patients, 21 male and 35 female, with a mean age of 35.8 ± 10.7 years, who underwent MMA was performed. Pre- and postoperative cone-beam computed tomography scans (CBCT) were obtained for each patient, and the changes in the UAS were compared using Dolphin Imaging 11.7 software. Two parameters of the pharyngeal airway space (PAS) were measured: airway volume (AV) and minimum axial area (MAA). Paired t-test was used to compare the data between T0 and T1, at 5% significance level. Results: There was a statistically significant increase in the UAS. Bimaxillary advancement surgery increased the AV and the MAA, on average, by 73.6 ± 74.75% and 113.5 ± 123.87%, respectively. Conclusion: MMA surgery tends to cause significant increase in the UAS; however, this increase is largely variable.

Sleep medicine in otolaryngology units: an international survey.

No study to date has described the overall landscape of sleep disorders management and training in otolaryngology departments of different countries. The aim of our study was to investigate and compare settings, diagnostic and therapeutic approaches and training programmes. An international online survey was developed with the collaboration of the YO-IFOS (Young Otolaryngologists-International Federation of Otorhinolaryngological Societies) to assess the current practice of otolaryngologists in the management of sleep disorders. The survey also included a session dedicated to training. A total of 126 otolaryngologists completed the survey. The larger part of responses was collected from Central/South America and Europe. The majority of responders from South/Central America (97%) declared to be certified as sleep specialist while 49% of Europeans stated the opposite. Of responders 83% perform a drug-induced sleep endoscopy (DISE) before planning a possible surgical intervention. Soft palate and base of tongue interventions were the most common procedure, respectively performed in 94% and 79% of the cases. Residents were allowed to perform soft palate surgery in 77% of the cases. Upper airway stimulation (26% vs 10%), trans-oral robotic surgery (36% vs 11%) and radiofrequency of the base of the tongue (58% vs 25%) were preferred more frequently by European responders. The highest caseloads of soft palate surgery and bi-maxillary advancement were registered in the academic institutions. Significant concordance and few interesting divergences in diagnosis and treatment of sleep disorders were observed between nationalities and types of institution. Economic resources might have played a significant role in the therapeutic choice. Trainees' lack of exposure to certain interventions and to a sufficient caseload appeared to be the main burden to overcome.

What are the Surgical Movements in Orthognathic Surgery That Most Affect the Upper Airways? A Three-Dimensional Analysis

Most studies have focused on airway changes after maxillomandibular advancement; however, airway size will change depending on the type, direction, and magnitude of each skeletal movement. The aim of this study was to assess the effect of the maxillary and/or mandibular movements on the pharyngeal airway volume and the minimum cross-sectional area using 3-dimensional cone-beam computed tomography voxel-based superimposition. The investigators designed and implemented a retrospective cohort study composed of patients with dentofacial deformity subjected to orthognathic surgery. The predictor variables were the surgical movements performed at surgery. The primary outcome variables were the pharyngeal airway volume and minimum cross-sectional area measured preoperatively, at 1- and 12-month follow-up. Skeletal and volumetric relapse and stability were recorded as secondary outcomes at 1 and 12months, respectively. Descriptive, bivariate and correlation analyses were computed. Significance was set at P<.05. The sample was composed of 103 patients grouped as follows: bimaxillary (53), maxillary (25), or isolated mandible (25). All of the surgical treatments resulted in a significant linear pattern of initial immediate increase of 33.4% (95% confidence interval [CI]: 28.2 to 38.7%; P<.001) in volumetric (nasopharynx [28.7%, CI: 22.7 34.9%; P<.001], oropharynx [36.2%, CI: 29.0 to 43.5%; P<.001], and hypopharynx [31.5%, CI: 25.7 to 37.3%; P<.001]) and minimum cross-sectional area parameters (bimaxillary=104%, [CI: 87.1 to 122.1%; P<.001], maxillary=39.5%, [CI: 18.4 to 60.7%; P<.05], and mandible=65.8%, [CI: 48.1 to 83.6%; P<.05]), followed by a slight downward trend (stabilization) at 12-month follow-up. Airway increase was favored by mandibular advancement (P<.05) and mandibular occlusal plane changes by counterclockwise rotation (P<.05). The results of this study suggest that there is a favorable effect of orthognathic surgery in the upper airway regardless of the surgical approach, with bimaxillary advancement and mandibular occlusal plane changes by counterclockwise rotation being the most significant contributors.

S4B-25 SESSION 4B: ORTHOGNATHIC / TREACHER-COLLINS MINIMAL DISRUPTION DISTRACTION IN SEVERE MANDIBULOFACIAL DYSOSTOSIS

Introduction: Severe Nager and Treacher Collins (TCS) patients frequently fail conventional distraction techniques. Degloving for osteotomy access and hardware retrieval delays bony healing and affects relapse. Further, high distraction forces in mandible-borne distractors may result in hardware failure, TMJ injury, or poor patient tolerance. To counter this, we designed a minimal access approach with transconjunctival high LeFort through reconstructed orbital floors combined with minimal dissection BSSO. Custom, non-buried anchorage devices permit aggressive, halo-borne counterclockwise traction. This approach has optimized airway outcomes and dramatically improved stable correction in our cohort. Methods: A total of 21 severe TCS or Nager patients underwent Lefort III/BSSO distraction osteogenesis were examined. 13 had prior MDO operation and 9 had a tracheostomy. Prior to Lefort III, malar and periorbital augmentation were performed using BMP2-soaked particulate allograft bone. This was performed serially (mean 2.7). Minimal dissection transconjunctival Lefort III and BSSO were then performed. Custom non-buried locking plates are designed to permit fixation between tooth roots. The maxillary plate is 1 piece to stabilize the hemimaxillas. The mandible plate is passed through a transmental tunnel to provide joystick-control of the distraction fragment. These are asymmetrically distracted from a RED device, the maxilla is consolidated once adequate counterclockwise advancement is achieved. The mandible is overdistracted to permit airway clearance and a consolidation period and/or intermaxillary fixation following distraction. Results: The number of distraction correlated with severity of midfacial deformity. In contrast, degree of micrognathia in infants and young children was not correlated with need for repeat distraction. Early mandibular distraction avoided secondary maxillary changes and was also associated with minimal loss of mandibular correction. Significant midface soft tissue advancement often required subsequent canthoplasty (14), midface bony contouring (10) or nasal dorsum augmentation with rib graft (4). 5 patients required a later bimaxillary advancement. Of the patients with tracheostomy 3/5 are decannulated and another two are eligible but prefer to finish ear reconstruction prior to decannulation. Conclusion: By combining minimal access techniques and custom hardware, we avoid soft tissue degloving and achieve enhanced outcomes in severe Treacher Collins and Nager syndrome. This regimen permits aggressive counterclockwise movement, more completely correcting both upper airway obstruction and facial aesthetics in patients with severe mandibulofacial dysostosis.

The effect of maxillary-mandibular advancement surgery on two-dimensional cephalometric analysis, polysomnographic and patient-reported outcomes in 32 patients with sleep disordered breathing: A retrospective cohort study

This retrospective study evaluated the effect of bimaxillary advancement surgery on pre- and postoperative 2D cephalometric soft- and hard tissue measurements, polysomnography (PSG) and patient-reported snoring scores including Epworth sleepiness scale (ESS) after multidisciplinary treatment planning in 32 patients with obstructive sleep apnea or sleep disordered breathing (OSAS/SDB). Apnea-hypopnea index significantly improved with a mean difference of 18.32 ± 13.97 (P = 0.004). ESS, snoring intensity and snoring severity scores all significantly improved after surgery. The preoperative surgical planning was achieved based on 2D pre- and postoperative cephalometric comparison. Most 2D cephalometric measurements did not correlate with postoperative PSG findings. Amount of maxillary and mandibular advancement measured on 2D cephalograms did correlate with postoperative time below 88% oxygen saturation on PSG. In conclusion: bimaxillary advancement surgery has clinically significant favourable results in patients with OSAS/SDB both measured by PSG and with patient-reported outcomes after careful multidisciplinary treatment planning. Current 2D cephalometric airway analysis insufficiently predicted the effect of maxillomandibular advancement surgery in patients with OSAS/SDB.

Pharyngeal Airway Modifications in Skeletal Class III Patients Undergoing Bimaxillary Advancement Surgery

The purposes were to study the pharyngeal airway in patients with skeletal Class III malocclusion submitted to surgical orthodontic treatment and to correlate the alterations with bone movements. The sample consisted of multislice computed tomography images from 13 patients obtained before and 6months after maxillomandibular advancement surgery. The following measurements were obtained using Dolphin Imaging software (Dolphin Imaging, Chatsworth, CA): volume and area of the oropharynx, nasopharynx, and total airway, as well as the most constricted area, anteroposterior and lateral dimensions of the narrowest axial cross-sectional area, and airway length. The paired ttest was applied at a significance level of 5%. Sagittal displacement of the maxilla and mandible was correlated with airway alterations using the Pearson correlation test. Alterations in airway measurements were observed in all patients after surgery. We noted a significant increase (P<.05) in total airway area, oropharyngeal area, and anteroposterior dimension of the most constricted area, as well as a significant reduction (P<.05) in airway length. A significant correlation (P<.05) was observed between nasopharyngeal area and maxillary movement and between airway length and mandibular movement (P<.05). The results of this study suggest significant alterations in pharyngeal airway measurements when preoperative and postoperative periods of bimaxillary advancement surgery were compared.