Changes In Airway Space Research Articles

Comparing posterior airway space changes in Class III patients treated with face mask and reverse chin cup

Objectives: The aim was to compare the posterior airway changes in patients treated with a face mask and reverse chin cup and to assess the stability over a 1.5-year follow-up period. Material and Methods: This historical cohort study consisted of two groups containing 20 patients with skeletal Class III malocclusion. The average age of the patients in groups one (Facemask) and two (reverse chin cup) was 7.77 ± 1.30 years and 8.6 ± 1.36 years, respectively. Seventeen cephalometric variables were measured before, after treatment, and after a 1.5-year follow-up. Comparisons were made within each group and between the two groups. Repeated measures, analysis of variance, or Friedman test were used. Results: There was no significant difference between the two groups in the posterior airway space. For patients who used face masks, six variables (AD1-posterior nasal spine [PNS], AD2-PNS, anterior nasal spine [ANS]-PNS, ANS-PNS-PPW, AA-PNS, and PNS-P) considerably increased (P < 0.05). In the reverse chin cup group, three variables (AD2-PNS, ANS-PNS-PPW, and PNS-P) considerably changed (P < 0.05). Moreover, no significant changes (P > 0.05) were observed in any variables after the 1.5-year follow-up period. Conclusion: In this study, the reverse chin cup and face mask effectively corrected Class III malocclusion and significantly increased the posterior airway space. The face mask showed greater enhancement compared to the reverse chin cup, and these improvements were maintained after a 1.5-year follow-up. However, the two groups had no significant difference regarding the posterior airway space changes.

Retrospective Analysis of the Airway Space Changes in Dentofacial Deformity after Two-Jaw Orthognathic Surgery Using Cone Beam Computed Tomography.

Orthognathic surgery is used to modify anomalies in maxillomandibular position; this process can significantly affect the anatomy of the airway and cause functional changes. This study aims to define the impact of mandibular maxillary movement on the airway of subjects with dentofacial deformity. A retrospective study was conducted on subjects with Angle class II (CII group) and Angle class III (CIII group) dentofacial deformities. The subjects were treated via bimaxillary surgery; for all of them, planning was performed with software and 3D printing. Cone beam computed tomography (CBCT) was obtained 21 days before surgery and 6 months after surgery and was used for planning and follow-up with the same conditions and equipment. Was used the superimposition technique to obtain the maximum and minimum airway areas and total airway volume. The data were analyzed with the Shapiro-Wilk test and Student's t-test, while Spearman's test was used to correlate the variables, considering a value of p < 0.05. Thus, 76 subjects aged 18 to 55 years (32.38 ± 10.91) were included: 46 subjects were in CII group, treated with a maxillo-mandibular advancement, and 30 subjects were in the CIII group, treated with a maxillary advancement and a mandibular setback. In the CII group, a maxillary advancement of +2.45 mm (±0.88) and a mandibular advancement of +4.25 mm (±1.25) were observed, with a significant increase in all the airway records. In the CIII group, a maxillary advancement of +3.42 mm (±1.25) and a mandibular setback of -3.62 mm (±1.18) were noted, with no significant changes in the variables measured for the airway (p > 0.05). It may be concluded that maxillo-mandibular advancement is an effective procedure to augment the airway area and volume in the CII group. On the other hand, in subjects with mandibular prognathism and Angle class III operated with the maxillary advancement and mandibular setback lower than 4 mm, it is possible to not reduce the areas and volume in the airway.

Quantification of pharyngeal airway space changes after two-jaw orthognathic surgery in skeletal class III patients

BackgroundSkeletal class III malocclusion is a common dentofacial deformity. Orthognathic treatment changes the position of the jaws and affects the shape of the upper airway to some extent. The aim of this study was to use multislice spiral computer tomography data and orthognathic knowledge to quantify the relationship between the amount of surgical movement of the maxilla or mandible in all three spatial planes and the changes in airway volume that occurred.MethodsA retrospective study of 50 patients was conducted. Preoperative and postoperative linear changes related to skeletal movements of the maxilla and mandible were measured and compared to changes in the most constricted axial level (MCA) and its anteroposterior (MCA-AP) and transverse diameters (MCA-TV). Correlation tests and linear regression analysis were performed.ResultsSignificant interactions were observed between the anterior vertical movement of the maxilla and the MCA-AP. The anteroposterior movement distance of the mandible was significantly correlated with changes in the oropharyngeal, velopharyngeal, total airway volume, MCA, MCA-AP, and MCA-TV. The change in the mandibular plane angle was significantly correlated with the change in velopharyngeal volume, total airway volume (nasopharynx, oropharynx, velopharynx), and MCA.The linear regression model showed that oropharyngeal volume decreased by 350.04 mm3, velopharyngeal volume decreased by 311.50 mm3, total airway volume decreased by 790.46 mm3, MCA decreased by 10.96 mm2 and MCA-AP decreased by 0.73 mm2 when point B was setback by 1 mm.ConclusionsAnteroposterior mandibular control is the key to successful airway management in all patients. This study provides estimates of volume change per millimeter of setback to guide surgeons in treatment planning.

Three Dimensional Skeletal, Dentoalveolar and Airway Space Changes after Slow Maxillary Expansion in Children

The aim of this study was to investigate the effects of slow maxillary expansion (SME) on the dentoalveolar, skeletal, upper airway, and maxillary sinus using cone-beam computed tomography (CBCT). Twenty-three orthodontic patients (mean age 8.93 ± 1.61 years) who were treated with maxillary expansion using banded hyrax in the Department of Pediatric Dentistry at Jeonbuk National University Dental Hospital were included. According to the expansion speed applied, they were divided into two groups: SME (12 subjects, mean age 8.92 ± 1.45 years) and rapid maxillary expansion (RME, 11 subjects, mean age 8.94 ± 1.84 years). CBCT were obtained before (T0) and after (T1) the treatment and were analyzed with InVivo5 software (Anatomage, San Jose, CA, USA). Descriptive statistics showed no significant differences between the two groups in age, sex, or skeletal maturity. There were significant increases in maxillary width at the dentoalveolar and skeletal levels for both groups. Upper airway volume revealed a significant increase of 38.59% in the SME group and 28.72% in the RME group. However, there was no significant difference between SME group and RME group in all measurements. This study suggested the efficacy of SME in growing patients. SME was effective in increasing not only dentoalveolar and skeletal measurements but also airway volume. Therefore, pediatric dentists should select an appropriate expansion method considering the physiological aspects of periodontal tissues and discomfort in growing children.

Three-Dimensional Pharyngeal Airway Space Changes Following Isolated Mandibular Advancement Surgery in 120 Patients: A 1-Year Follow-up Study.

Lack of evidence exists related to the three-dimensional (3D) pharyngeal airway space (PAS) changes at follow-up after isolated bilateral sagittal split osteotomy (BSSO) advancement surgery. The present study assessed the 3D PAS changes following isolated mandibular advancement at a follow-up period of 1 year. A total of 120 patients (40 males, 80 females, mean age: 26.0 ± 12.2) who underwent BSSO advancement surgery were recruited. Cone-beam computed tomography (CBCT) scans were acquired preoperatively (T0), immediately following surgery (T1), and at 1 year of follow-up (T2). The volume, surface area, and minimal cross-sectional area (mCSA) of the airway were assessed. The total airway showed a 38% increase in volume and 13% increase in surface area from T0 to T1, where the oropharyngeal region showed the maximum immediate change. At T1–T2 follow-up, both volumetric and surface area showed a relapse of less than 7% for all sub-regions. The mCSA showed a significant increase of 71% from T0 to T1 (p < 0.0001), whereas a non-significant relapse was observed at T1–T2 (p = 0.1252). The PAS remained stable at a follow-up period of 1 year. In conclusion, BSSO advancement surgery could be regarded as a stable procedure for widening of the PAS with maintenance of positive space at follow-up.

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

BackgroundThis 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.MethodsA 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.ResultsIn 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).ConclusionIn 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.

Pharyngeal airway space changes and stability following an extended LeFort-I osteotomy advancement in cleft lip and palate and non-cleft lip and palate patients: A long term comparison study

PurposeThe aim of this study was to evaluate effects of extended maxillary advancement osteotomy on pharyngeal airway space (PAS) in mid-facial deficient cleft lip and palate (CLP) patients and mid-facial deficient non-CLP patients. MethodsPharyngeal airway space (PAS) of 10 CLP and 10 non-CLP patients with the mean age of 19 years 10 months was measured on digitized lateral cephalograms taken shortly before maxillary advancement operation with Quadrangular Le Fort I osteotomy (QLF-I) (T0), early post-operative, (T1) and long term post-operative (T2). Two way repeated analysis of variance, independent samples t-test and correlations tests were used for statistical analysis of airway and skeletal changes. ResultsTotal PAS depth and area was significantly increased after the advancement and was stable in long term post-operative period for CLP and non-CLP patients. Nasopharyngeal and velopharyngeal airway space depth and area was statistically increased at T1 and T2 for both groups. Oropharyngeal airway depth and area showed no significant statistical difference at any of the time points. The effect of QLF-I osteotomy on (PAS) was similar in both CLP and non-CLP patients. ConclusionsNasopharyngeal, velopharyngeal, and total pharyngeal airway space depth and area increased after maxillary advancement with the QLF-I osteotomy; this increase was stable in long term follow up. Maxillary advancement with the QLF-I technique had no significant effect on oropharyngeal airway space depth and area in both CLP and non-cleft patients.

Upper airway changes in Class III patients using miniscrew-anchored maxillary protraction with hybrid and hyrax expanders: a randomized controlled trial.

The aim of this study was to compare the upper airway space changes after miniscrew-anchored maxillary protraction with hybrid (HH) and conventional hyrax (CH) expanders. The sample comprised Class III malocclusion growing patients that were randomized into two groups of miniscrew-anchored maxillary protraction. The group HH was treated with a hybrid hyrax appliance in the maxilla and two miniscrews distally to the canines in the mandible. Class III elastics were used from the maxillary first molar to the mandibular miniscrews until anterior crossbite correction. The group CH was treated with a similar protocol except for the conventional hyrax expander in the maxilla. Cone-beam computed tomography was obtained before (T1) and after 12 months of therapy (T2). The shape and size of upper airway were assessed. Intergroup comparisons were performed using Mann-Whitney U test (p < 0.05). The group HH was composed of 20 patients (8 female, 12 male) with a mean age of 10.76 years. The group CH was composed of 15 patients (6 female, 9 male) with a mean age of 11.52 years. Anteroposterior and transverse increases of the upper airway were found for both groups. The oropharynx and the most constricted area increased similarly in both groups. No differences in upper airway changes were observed using protraction anchored on hybrid or conventional hyrax expanders. Maxillary protraction anchored on hybrid or conventional hyrax expanders may benefit patients with breathing disorders due to the increase of the upper airway volume and most constricted area. Registration: ClinicalTrials.gov (NCT03712007).

Total maxillary arch distalization with modified C-palatal plates in adolescents: A long-term study using cone-beam computed tomography

The aims of this study were to evaluate the long-term skeletodental effects, the volume of maxillary tuberosity, and airway space changes after maxillary molar distalization using modified C-palatal plate (MCPP) in adolescents with Class II malocclusion. The sample consisted of 20 adolescent patients (MCPP group; mean age, 12.9±1.0year) who underwent bilateral distalization of their maxillary dentition and 20 subjects as a control group. In the MCPP group, cone-beam computed tomography images were taken before distalization, at the end of the treatment, and during retention with a minimum of a 3-year posttreatment follow up period. Repeated measures ANOVA followed by post-hoc analysis with the Bonferroni test were used to identify significant differences between time points. After the long-term observation period, sagittal skeletal and dental relationships were maintained (there were no significant changes in ANB, occlusal plane angle, and overjet postretention). The vertical skeletal dimension did not change during treatment and was stable at the long-term follow-up (the mandibular plane angle and ANS-Me were relatively well maintained). The volume of the maxillary tuberosity showed no significant change during long-term retention. However, the volume was significantly smaller in the treatment group than in the control group (P<0.0001). There were no significant airway space changes after distalization and the postretention period. In addition, there was no significant difference between the MCPP and control groups. Improved sagittal skeletal and dental relationships because of treatment were maintained in the long-term evaluation. There was no negative long-term effect on airway space associated with the maxillary arch distalization. Therefore, these findings might be beneficial for clinicians in diagnosis and treatment planning for Class II malocclusion in adolescents.

Evaluation of the airway space changes after extraction of four second premolars and orthodontic space closure in adult female patients with bimaxillary protrusion – A retrospective study

Background & objectivesPrevious studies have found that first premolar extractions during orthodontic treatment may alter the upper airway dimensions. The objective of this study is to investigate the effects of second premolar extraction during orthodontic treatment on the dimensions of the upper airway in a sample of female adults. MethodsTwenty-nine female adult patients with ages between 18 and 30 years old and incisor bimaxillary protrusion were included in this study. They were treated with comprehensive orthodontic treatment which included the extraction of four second premolars. Pre and post cephalometric radiographs were analyzed using Dolphin imaging software for changes in tongue length and height, soft palate thickness and length, the superior, middle, and inferior airway space, and vertical airway length. Descriptive statistics were used to characterize measurements. Student’s paired t-test was preformed to compare the pre- and post-test mean values of the dimensions. ResultsA significant increase in the vertical airway length was observed after the extraction of the second premolars (p = 0.02). The soft palate length showed a tendency towards an increase that did not reach statistical significance (p = 0.053). No other significant changes in the airway soft tissue measurements were observed. The proclination and protrusion of the upper and lower incisors were significantly decreased compared to pre-treatment measurements.Interpretation & conclusions.Orthodontic treatment involving the extraction of all four second premolars in females with bimaxillary protrusion increases the vertical airway length, which is the amount of distance between base of the tongue and posterior nasal spine. No other significant alterations in the upper airway measurements were observed.

Cone-Beam Computed Tomography Evaluation of Pharyngeal Airway Space Changes After Bimaxillary Orthognathic Surgery in Patients With Class III Skeletal Deformities: A 6-Year Follow-Up Study

The aim of the present study was to investigate the volumetric and 2-dimensional (2D) changes in the pharyngeal airway space (PAS) after bimaxillary orthognathic surgery (maxillary advancement and mandibular set back) in patients with skeletal Class III deformities. In the present retrospective study, patients with skeletal Class III deformities were treated at Pusan National University Hospital (Busan, South Korea) and had undergone cone-beam computed tomography examination preoperatively, immediately postoperatively, 6.0±0.6months postoperatively, and 6.2±1.3years postoperatively. The anteroposterior length (APL), largest transverse width (LTW), and cross-sectional area (CSA) at 4 reference planes and the PAS volume were measured. Spearman's correlation analysis was used to assess the correlation between the PAS changes and skeletal movements. The subjects included 11 men and 12 women. Their mean age was 22.7±4.7years (range, 18 to 33years). The APL and CSA on the PNS-Vp, CV1, and CV2 planes, the LTW on the CV1 plane, and the oropharyngeal and total volume had decreased at 6months postoperatively. However, thereafter, no significant 2D or volumetric changes were observed until 6.2years postoperatively. The long-term change of the LTW on the CV3 plane correlated negatively with mandibular relapse. The volume and morphology of the 6-month postoperative changes in PAS were stable at 6years for patients who had undergone maxillary advancement and mandibular setback.

Pharyngeal airway evaluation following isolated surgical mandibular advancement: A 1-year follow-up.

The aim of this study was to evaluate the stability of pharyngeal airway space changes with the use of acoustic pharyngometry 1year after bilateral sagittal split ramus osteotomy for mandibular advancement in patients with skeletal Class II malocclusion. The sample comprised 16 patients (mean age 21.26±1.86years). Acoustic pharyngometry measurements were recorded 1week before surgery (T0), 2months after surgery (T1), and 1year after surgery (T2). Parameters were compared by means of repeated-measures analysis of variance (ANOVA). Significant increase was seen in minimum cross-sectional area 2months after surgery (P<0.001). Relapse of 12.6% was observed within 1year after surgery (P<0.001). Statistically significant increase, ie, 31.5%, was seen in mean cross-sectional area 2months after surgery (P<0.001), which relapsed by 7.9% 1year after surgery (P<0. 0.001). Significant increase in mean volume from 30.32±2.2cm3 before surgery to 38.91±2.73cm3 2months after surgery (P<0.001) was observed. Mean volume relapsed 3.9% 1year after surgery (P<0.001). Changes in pharyngeal airway space dimensions in patients subjected to isolated surgical mandibular advancement on 1year follow up showed encouraging results.

Pharyngeal airway space changes after maxillomandibular advancement: a five-year retrospective study

The aim of this study was to compare the alterations in three regions of the airway—nasopharynx, oropharynx, and hypopharynx—in relation to the area of the midsagittal plane, volume, and minimal axial area after maxillomandibular advancement (MMA) surgery. Thirty patients who had undergone MMA surgery were evaluated at four time points: preoperative (T0), immediately postoperative (T1), 1year postoperative (T2), and ≥5 years postoperative (T3). All measurements were performed using computed tomography, analyzed in Dolphin Imaging 11.0 Premium 3D software. The area in the midsagittal plane presented a mean increase of 22.0% between T0 and T3 (P<0.001), with the highest increase in the oropharynx (24.1%, P<0.001). The total volumetric increase at T3 was 16.7% (P<0.001), with the highest increase in the nasopharynx (15.7%; P<0.001). The lowest minimal axial area was found for the oropharynx at all time points, and the highest increase in minimal axial area was found for the nasopharynx (114.9%; P<0.001). MMA surgery showed the highest increase in upper posterior airway between T0 and T1, and this was followed by a progressive reduction until T3, but with a statistically significant increase at T3 compared with T0 in all cases.

Three-dimensional analysis of changes in airway space after bimaxillary orthognathic surgery with maxillomandibular setback and their association with obstructive sleep apnea

BackgroundBimaxillary orthognathic surgery with maxillomandibular setback is often accompanied by changes in airway space. We analyzed the changes in airway space before and after surgery and assessed their association with obstructive sleep apnea.MethodsThis study is based on the cohort of 13 adult patients (9 males, 4 females, average age 23.85 years) who underwent bimaxillary orthognathic surgery with maxillomandibular setback.We performed computed tomography and portable polysomnography before and after the surgery to assess changes in airway space and Apnea-Hypopnea Index (AHI) values (total, supine, non-supine).ResultsThe oropharyngeal airway volume decreased by 29% after the surgery, which was statistically significant (p < .05). The upper airway volume and hypopharyngeal airway volume were decreased, but not significantly (4 and 19%, respectively). The changes in airway surface area were statistically significant at all levels examined (p < .05). Changes in the maximum anteroposterior width of the airway were also significant at all levels (p < .05). However, the changes in maximum lateral width were only statistically significant at C2 level (p < .05). AHI values were increased after the surgery but not significantly at any position.ConclusionsAlthough bimaxillary surgery with maxillomandibular setback significantly reduces the airway space, it does not affect AHI values or induce obstructive sleep apnea.

Three-dimensional evaluation of maxillary dentoalveolar changes and airway space after distalization in adults.

To evaluate the changes in position of the maxillary dentition and the airway space after distalization using a modified C-palatal plate (MCPP) in adult patients through CBCT images and to analyze the relationship between the amount of distalization and the changes in the airway space. CBCT images of 33 adult Class II patients (22.2 ± 4.0 years old; 27 women and 6 men) treated by total maxillary arch distalization using the MCPP were evaluated before and after distalization. The patients were divided into nonextraction and extraction groups. The changes in the airway space as well as the changes in the positions of the maxillary dentition were evaluated. The distalization effects were calculated and assessed using paired t-tests. After distalization, the first molar showed significant distalization and intrusion ( P < .001) with no significant rotation of the crown and no significant buccal displacement of its root in the transverse dimension. There were no significant changes in the airway volume or the minimum cross-sectional area of the oropharynx. The application of the MCPP resulted in significant total arch distalization without a significant effect on the transverse dimensions or changes in the oropharynx airway space. The MCPP can be considered a viable treatment option for patients with Class II malocclusion.

Pharyngeal airway changes after mono-maxillary advancement surgery

Introduction/Objective. Maxillary or mandibular retrognathism are common dentofacial deformities treated by combined orthodontic-surgical treatment. Surgical maxillary or mandibular advancement changes the position and strain of surrounding structures, which may also affect pharyngeal airway dimensions. The aim of this study was to evaluate and compare three-dimensional pharyngeal airway space changes in patients treated with maxillary advancement and those treated with mandibular advancement. Methods. The sample consisted of 25 patients ? 12 treated with maxillary advancement and 13 with mandibular advancement surgery. Nasopharyngeal (NP) volume, oropharyngeal (OP) volume, and the area of maximum constriction (AMC) in the OP were measured on cone beam computed tomography scans (2 mA / 120 kV / 12?? FOV) taken before and at least three months after surgery. Paired samples t-test was used for analyzing statistical significance of changes (p ? 0.05). Results. Postoperative OP and NP volumes, as well as the AMC, increased insignificantly in both groups. Conclusion. Results suggest that mono-maxillary surgical advancement of the maxilla or the mandible increases pharyngeal airway dimensions.

Tomographic Analysis of the Impact of Mandibular Advancement Surgery on Increased Airway Volume.

Purpose:This study aimed to quantify, using cone-beam computed tomography (CBCT) in patients who underwent a mandibular advancement surgery associated with genioplasty, three-dimensional changes in airway space and to evaluate whether these changes differ between men and women.Materials and Methods:Preoperative and 8-month postoperative CBCT scans of 38 patients aged 18–45 years of either sex and any ethnicity who underwent mandibular advancement surgery associated with genioplasty were analyzed using the Xoran software (Xoran Technologies, Ann Arbor, MI, USA). The linear distances gonion-gnathion (Go-Gn) and condylion-menton (Co-Me) were obtained. Airway volume was measured using the Dolphin Imaging software, version 11.0. Then, data were tabulated and analyzed using Student's t-test.Results:Mean patient age was 30.3 years; 39.47% were men and 60.63% were women. The mean Go-Gn distance was 72.05 mm before surgery and 78.56 mm after surgery, with a mean gain of 6.51 mm. The mean Co-Me distance was 113.47 mm before surgery and 119.89 mm after surgery, with a mean increase of 6.42 mm. Both differences were statistically significant. The mean volume of airway space was 17,272.92 mm3 before surgery and 24,173.74 mm3 after surgery, with a statistically significant mean increase of 6900.82 mm3. There was no statistically significant difference in mean volumetric gain between men (7566.69 mm3) and women (7456.69 mm3).Conclusion:Mandibular advancement surgery results in significant increase of airway space, and there is no difference in airway volume between men and women.

A retrospective cephalometric study on pharyngeal airway space changes after rapid palatal expansion and Herbst appliance with or without skeletal anchorage.

BackgroundThe aim of this study is to investigate the pharyngeal airway space changes in patients treated with rapid palatal expansion (RPE) and Herbst appliance with or without skeletal anchorage.MethodsA 40-patient study group treated with the Herbst RME combination was included; moreover, a comparison between two subgroups based on whether miniscrews were used was evaluated. A subgroup 1 included 20 patients who were treated with RPE and an acrylic splint Herbst with miniscrews, and subgroup 2 included 20 patients who were treated with RPE and an acrylic splint Herbst. A cephalometric analysis was performed before (T1) and after (T2) treatment. The skeletal parameters of the sagittal occlusion analysis of Pancherz were utilized together with some extra measurements to evaluate the airways.ResultsAn increased nasopharyngeal airway space was observed in group 1 (p < 0.05) from T1 to T2. Furthermore, the increase in nasopharyngeal airway space was significantly higher in subgroup 1 (p < 0.05) in comparison to the subgroup 2. Oropharyngeal (OA) and laryngopharyngeal (LA) dimensions were significantly increased in the subgroup 1 at the end of the treatment. In the subgroup 1, a significant decrease in SNA, a significant increase in SNB, and a significant decrease in ANB were observed from T1 to T2. In the subgroup 2, the treatment resulted in a significant decrease in ANB. In both groups, Pogonion increased significantly from T1 to T2.ConclusionsThe results suggest that the RPE and the Herbst appliance allow a slight improvement of the sagittal dimensions of the airways. The oropharyngeal dimension increased significantly more in the skeletal anchorage group.

Abstract: The Change of Posterior Pharyngeal Space after Counter Clock-wise Rotational Orthognathic Surgery Based on Cephalometry

INTRODUCTION: Maxillomandibular advancement (MMA) is an orthognathic surgical procedure that has been used to manage OSA in individuals who are noncompliant with CPAP therapy.1 MMA is a site-specific procedure, performed for the purpose of creating an enlarged posterior airway space at multiple anatomic levels, including the nasopharynx, oropharynx, and hypopharynx.2 MMA has been shown to significantly improve OSA, with reported short term success rates ranging from 75% to 100%.3–5 This prospective investigation describes the functional and aesthetic outcomes after the counter clock wise rotational orthognathic surgery in skeletal class II patients with the obstructive sleep apnea based on pre and postoperative polysomnography and cephalometry. MATERIALS AND METHODS: This retrospective study investigated the surgical outcome of 12 patients who suffered from obstructive sleep apnea following the counter clock wise rotational orthognathic surgery in terms of functional and aesthetic outcomes. The patients included in this study were skeletal class II patients who underwent orthognathic surgery between March, 2013 and December, 2014 at the Seoul Asan Medical Center, University Medical Center for tertiary care. The pharyngeal airway assessment was done through polysomnography and cephalometric posterior airway analysis using PRL–PSP, PRL–PTO and PRL–E distances. RESULTS: The follow-up period ranged from 10 to 36 months (average, 20.5 months). The average age of the patients was 28.5 years, with 9 male and 11 female patients. Compared to preoperative results (mean preop distance of PRL–PSP: 19.97, PRL–PTO: 18.68, PRL–E: 16.2), PRL–PSP, PRL–PTO and PRL–E distances were increased statistically significant in immediate postoperative cephalometry. (p<0.005) (mean immediate postop distance of PRL–PSP: 23.1, PRL–PTO: 22.9, PRL–E: 18.6). The results were maintained 6 months after the surgery(mean distant postop distance of PRL–PSP: 22.2, PRL–PTO: 22.5, PRL–E: 18.0). There was no significant change in PRL–PSP, PRL–PTO and PRL–E distances.(p>0.05). CONCLUSION: The change of the posterior pharyngeal space in counter clock-wise rotational orthognathic surgery without maxilla advancement for the correction of obstructive sleep apnea is presented. Our findings indicate that this approach can lengthen the posterior pharyngeal space effectively. With considered application, this novel approach could be an alternative to standard approaches in the correction of obstructive sleep apnea using orthognathic surgery. DISCLOSURES/FINANCIAL SUPPORT:None of the authors has a financial interest in any of the products, devices, or drugs mentioned in this manuscript. REFERENCES: 1. Fernández-Ferrer L, Montiel-Company JM, Pinho T, Almerich-Silla JM, Bellot-Arcís C. Effects of mandibular setback surgery on upper airway dimensions and their influence on obstructive sleep apnoea - a systematic review. J Craniomaxillofac Surg. 2015;43:248–53. 2. Demetriades N, Chang DJ, Laskarides C, Papageorge M. Effects of mandibular retropositioning, with or without maxillary advancement, on the oro-naso-pharyngeal airway and development of sleep-related breathing disorders. J Oral Maxillofac Surg. 2010;68:2431–6. 3. Gonçalves JR, Gomes LC, Vianna AP, Rodrigues DB, Gonçalves DA, Wolford LM. Airway space changes after maxillomandibular counterclockwise rotation and mandibular advancement with TMJ Concepts® total joint prostheses: three-dimensional assessment. Int J Oral Maxillofac Surg. 2013;42:1014–22. 4. Hatab NA, Konstantinović VS, Mudrak JK. Pharyngeal airway changes after mono- and bimaxillary surgery in skeletal class III patients: Cone-beam computed tomography evaluation. J Craniomaxillofac Surg. 2015;43:491–6. 5. Jakobsone G, Stenvik A, Espeland L. The effect of maxillary advancement and impaction on the upper airway after bimaxillary surgery to correct Class III malocclusion. Am J Orthod Dentofacial Orthop. 2011;139:e369-76.

Posterior Pharyngeal Airway in Clockwise Rotation of Maxillomandibular Complex Using Surgery-first Orthognathic Approach.

Background:Because obstructive sleep apnea is known to be an important preexisting factor causing chronic disease, many investigations have been done recently. There have been few reports regarding the posterior pharyngeal airway after clockwise rotation of maxillomandibular complex. Because the 2-jaw surgery in class III patients could cause obstructive sleep apnea or snoring, we investigated the posterior pharyngeal airway change of the clockwise maxillomandibular complex in the surgery-first orthognathic approach for the correction of class III dentofacial deformities.Methods:A cephalometric evaluation of 35 patients with skeletal class III deformity was performed preoperatively and postoperatively. Three measurements of the posterior pharyngeal airway space (nasopharynx, oropharynx, and hypopharynx) and hyoid bone positions (the distance from palatal plane to hyoid bone and the distance from mandibular plane to the hyoid bone) were evaluated and correlated with the skeletal movement of the jaws using imaging software (V-Ceph, Osstem, Seoul, Korea).Results:The preoperative airway space turned out to be enlarged in class III dentofacial deformities compared with those of normal persons. The preoperative P1, P2, and P3 in our cohort were increased and posterior nasal spine to hyoid bone and mandibular plane to hyoid bone were decreased compared with those of normal person’s data because the cohort consists of prognathic patients where the mandible is located in forward position. After 6 months, most values were nearly normal.Conclusion:Orthognathic surgery based on clockwise rotation of maxillomandibular complex did not cause severe posterior airway space changes at 6 months postoperation.