Volume Of Upper Airway Research Articles

Quantitative changes of upper airway in class III patients undergoing bimaxillary surgery after one-year follow-up: a retrospective study

BackgroundBimaxillary surgery is often performed for class III malocclusion, and its complex influence on the upper airway has been well considered. The aim of this research was to provide a scaled formula between upper airway volume changes and bone movements in Class III patients after orthognathic surgery.Materials and methodsUsing a retrospective study design, the investigators enrolled a total of 30 class III malocclusion patients who were undergoing bimaxillary surgery as the study subjects. The subjects included 15 males and 15 females, and their average age was 23.3 ± 3.4 years. CBCT (cone beam tomography) was performed both before and one year after the surgery for each patient. The changes in the soft palate, tongue and upper airway were measured by using CBCT data that was collected before and after surgery. 3D superimposition of CBCT was performed to calculate three-dimensional jaw movements. A multiple regression analysis was used to calculate the quantitative relationship between airway volume changes and jaw movements.ResultsThe nasopharynx airway volume was observed to be increased by 1064.0 ± 1336.2 mm3, whereas the retropalatal and retroglossal airway volumes were observed to be decreased by 1399.0 ± 2881.6 mm3 and 1433.8 ± 3043.4 mm3, respectively, after the surgery. One millimetre forward and downward movements of the PNS resulted in increases of 626.90 mm3 and 392.18 mm3 in nasopharynx airway volume, respectively. Moreover, one millimetre retrogression of the B point caused decreases of 314.6 mm3 and 656.6 mm3 in the retropalatal and retroglossal airway volume, respectively. The changes in the soft palate contributed to the decrease in the retropalatal airway volume, whereas the tongue compensated for the decrease in the retroglossal airway volume.ConclusionThe movements of the PNS and B points could be used to predict upper airway volumetric changes in Class III patients after maxillary advancement and mandibular setback.

Modified biblock versus monoblock mandibular advancement appliances for treatment of obstructive sleep apnea: A randomized controlled trial

Statement of problemThe high prevalence of obstructive sleep apnea represents a serious public health problem. Oral appliances have gained wide acceptance among patients diagnosed with obstructive sleep apnea, who should wear them every night. A comfortable oral appliance is mandatory for successful treatment outcomes. PurposeThe purpose of this randomized controlled trial was the assessment of the influence of 2 different designs of the mandibular advancement appliance (MAA), modified biblock and monoblock, for the management of obstructive sleep apnea. Material and methodsThe study was designed as a prospective 2-arm randomized controlled clinical trial conducted in parallel. Twenty participants (aged 40 ±7.5 years) diagnosed with moderate obstructive sleep apnea were randomly assigned to a control group (n=10), receiving monoblock MAA, and a study group (n=10), receiving modified biblock MAA with elastics. Both appliances were fabricated by using computer-aided design and computer-aided manufacture (CAD-CAM) technology at different mandibular advancement levels (MALs): 50% and 75% of maximum MAL. A total of 60 cone beam computed tomography scans, 60 overnight full polysomnography sleep tests, 60 STOP-Bang questionnaires, and 40 Usability of Sleep Apnea Equipment-Oral Appliance (USE-OA) questionnaires were collected and analyzed blindly at baseline (initial visit), 50% MAL (3 months), and 75% MAL (6 months). The main outcome measures were the upper airway volume, linear anteroposterior and cross-sectional airway measurements, Apnea Hypopnea Index, Respiratory Disturbance Index, STOP-Bang questionnaire scoring, and USE-OA questionnaire scoring. Nonparametric statistical analysis was performed by using a statistical software program (α=.05). With a beta error accepted of up to 20%, the power of the study was 80%. ResultsAt 75% MAL, the percentage change in upper airway volumetric measurements showed a favorable increase: biblock group (115%) and monoblock group (42%), with a statistically significant difference (P=.001). The linear anteroposterior airway measurements and the percentage change in cross-sectional airway measurements were statistically similar: biblock group (80%) and (75%) monoblock group (60%), (54%) (P=.450, P=.151, respectively). The percentage change in the Apnea Hypopnea Index significantly decreased: biblock group (-89%) and monoblock group (-54%) (P<.001). The percentage change in the Respiratory Disturbance Index decreased: biblock group (-78%) and monoblock group (-62%) (P<.023). From the STOP-Bang questionnaire scoring, 100% of both groups showed low risk for obstructive sleep apnea at 75% MAL. From the satisfaction scoring on the USE-OA questionnaire, the biblock group was 100% strong satisfaction and the monoblock group was 50% satisfaction and 50% fairly satisfied. ConclusionsThe modified biblock MAA with elastics showed significant improvements in patients diagnosed with obstructive sleep apnea regarding upper airway measurements and full polysomnography vital parameters when compared with monoblock MAA.

Effect of premolar extraction on upper airway volume and hyoid position in hyperdivergent adults with different mandibular length

The objective of this study was to investigate the morphological changes of the upper airway and the position of the hyoid bone in hyperdivergent adults with different mandibular lengths after premolar extraction. The data of57 hyperdivergent adults, aged 20-35 years, who had 4 premolar extractions were included for the study. Mandibular length (CoGn) was used for grouping (A: long CoGn, B: short CoGn). Pretreatment and posttreatment lateral cephalograms and cone-beam computed tomography images were used to assess the position of mandible, hyoid bone, and upper airway using paired t test. An independent sample ttest was used to detect changes of the airway and hyoid position between groups A and B. Pearson correlation analysis was applied to estimate the correlation between pharyngeal spaces and dentoskeletal morphology at P<0.05. In all subjects, we observed retraction of the upper incisors, mesial movement of the lower molars, and reduction of the mandibular planes. In group A, differences were found in anterior and posterior movements of the hyoid bone, increase of airway volume, minimum cross-sectional area (MCA) and anteroposterior linear distance (APL) (P<0.05). There were notable differences in the change of hyoid position, airway volume, MCA, and APL between group A and group B. Glossopharyngeal and hypopharyngeal volumes, MCA, and APL were correlated with articular angle, mandibular plane, and hyoid bone position (P<0.05). With a comprehensive diagnosis and treatment, premolar extraction in hyperdivergent adults with favorable CoGn can facilitate improvement of esthetics, hyoid bone position, and the increase in glossopharyngeal and hypopharyngeal volumes and MCA.

Upper Airway Changes in Diverse Orthodontic Looms: A Systematic Review and Meta-Analysis

Upper airway assessment is particularly important in the daily work of orthodontists, because of its close connection with the development of craniofacial structures and with other pathologies such as Obstructive Sleep Apnea Syndrome (OSAS). Three-dimensional cone-beam computed tomography images provide a more reliable and comprehensive tool for airway assessment and volumetric measurements. However, the association between upper airway dimensions and skeletal malocclusion is unclear. Therefore, the current systematic review evaluates the effects of different surgical movements on the upper airway. Materials and Methods: Medline (PubMed, OVID Medline, and EBSCO), Cochrane Library (Cochrane Review and Trails), Web of Knowledge (social science, and conference abstracts), Embase (European studies, pharmacological literature, and conference abstracts), CINAHL (nursing and allied health), PsycInfo (psychology and psychiatry), SCOPUS (conference abstracts, and scientific web pages), and ERIC (education) databases were searched. Two authors independently performed the literature search, selection, quality assessment, and data extraction. Inclusion criteria encompassed computed tomography evaluations of the upper airway spaces with retrospective, prospective, and randomised clinical trial study designs. To grade the methodological quality of the included studies a GRADE risk of bias tool was used. Results and conclusion: In total, 29 studies were included. Among these, 17 studies had a low risk of bias, whereas 10 studies had a moderate risk of bias. A meta-analysis was performed with the mean differences using a fixed-effects model. Heterogeneity was assessed with the Q-test and the I2 index. The meta-analysis revealed significant (p ≤ 0.001, 95% confidence interval) increases in upper airway volume after rapid maxillary expansion and surgical advancement for the correction of Class II.

Airway changes after fixed functional appliance treatment in children with and without morphologic deviations of the upper spine: A 3-dimensional CBCT study

Functional appliances (FA) have a positive effect on the upper airway volume and minimal cross-sectional area (MCA) in children. An association between morphologic deviations of the upper spine (MDUS) and reduced treatment response was found in appliances used to treat adults with obstructive sleep apnea. This study aimed to: (1) compare airway changes after FA treatment in children with and without MDUS and controls; (2) identify if MDUS causes a smaller upper airway. Pretreatment and posttreatment cone-beam computed tomography scans were included from 21 children with MDUS and 42 without MDUS treated with a fixed FA, along with a pair-matched control group (matched for chronological age, skeletal age, gender, and mandibular inclination) who received orthodontic treatment for minor malocclusions without an FA. The influence of MDUS on changes in upper airway volume and MCA were evaluated with 3-dimensional cone-beam computed tomography scans using standardized, previously validated methods and mixed-effects linear regression. There was a significantly increased volume and MCA in the FA groups with and without MDUS compared with control (P= 0.003 and P= 0.049) and in the FA group without MDUS compared with the MDUS group (P= 0.008 and P= 0.011) after treatment. There was no significant pretreatment difference in airway dimensions between the MDUS and non-MDUS FA groups. The airway response with fixed FA is significantly reduced in MDUS children. MDUS caused no significant pretreatment airway differences in children. However, MDUS may be important in predicting airway changes in FA treatment.

Multivariable analysis of the associations between transversal maxilla size and upper airway volume

To assess the relationship between the size of the upper jaw and the volume of the upper respiratory tract in adult patients, both in the form of continuous indicators and in the form of categorical variables. Cone-beam computed tomography images of all patients (n=365) aged 18-60 years who attended one of the dental clinics in Arkhangelsk (Northwest Russia) from October 2019 through November 2020 comprised the study base. Maxilla size and upper airway volume were assessed using Ez3D-I software. Bivariate analysis of categorical variables was performed using Pearson's chi-squared tests. Continuous variables were compared using unpaired Student's t-test. Independent associations between maxilla size and upper airway volume were assessed by multivariable linear regression analysis adjusted for age and gender. No associations between maxilla size and upper airway volume were observed in bivariate analysis. Adjustment for potential confounders in multivariable analysis has not changed the initial results on no associations between the studied variables with 95% confidence level. In contrast with the results of many previous studies, our findings suggest no association between transversal maxilla size and upper airway volume. Patients with reduced maxilla size are equally likely to have normal and reduced upper airway volume. Further research on larger samples is needed to corroborate our findings.

Advances in the Study of Upper Airway Characteristics in Children with Malocclusion

Malocclusion is the malformation of teeth, jaw and skull caused by congenital genetic factors or acquired environmental factors in the process of children's growth and development, such as diseases, bad oral habits, abnormal substitute teeth, such as irregular arrangement of teeth, abnormal relationship between upper and lower dental arch, abnormal jaw size and shape, etc. Malocclusion is also accompanied by respiratory diseases and dysfunction, such as obstructive sleep apnea (OSA). Conversely, abnormal occlusion also leads to respiratory tract developmental disorders and dysfunction. The cranio-maxillofacial morphology is closely related to the upper airway morphology. They are cause and effect each other. In recent years, it has been found that orthodontic treatment can not only improve the malocclusion, but also has a significant effect on the upper airway volume. The abnormal upper airway in childhood will affect children's breathing, cause children's sleep apnea, and affect children's growth and development. At the same time, with the development of society, we pay more attention to children's face. Therefore, at present, the upper airway morphological characteristics, influencing factors and correction methods of malocclusion have become the focus of research.

Three-dimensional changes in the upper airway and craniomaxillofacial morphology of patients with Angle Class III malocclusion treated with a Frankel III appliance

BackgroundAngle Class III malocclusion, characterized by a concave profile, can cause serious harm to children’s physical and mental health. The Frankel III appliance is an effective treatment for Angle Class III malocclusion in mixed denition. We explored three-dimensional changes in the upper airway and craniomaxillofacial morphology, after one year of Frankel III appliance treatment, in children with Angle Class III malocclusion.MethodsWe included 20 children (9 males), aged 8–10 years, with Angle Class III malocclusion from the Orthodontics Department of our hospital. Each child was treated with a Frankel III appliance for one year. Cone beam computed tomography was performed before and after treatment to evaluate three-dimensional changes in the upper airway and craniomaxillofacial morphology.ResultsAfter one year of treatment, in the upper airway, we observed significant increases in the nasopharynx volume and height (P < 0.05); the velopharyngeal volume, height, and average cross-sectional area (P < 0.05); the glossopharynx volume and minimum cross-sectional area (P < 0.05); and the laryngopharynx height (P < 0.05). Accordingly, the total upper airway volume, height, and average cross sectional area increased significantly (P < 0.05). An examination of craniomaxillofacial morphology showed significant increases in some bone tissues (P < 0.05) and dental measurements, and a significant reduction in the inclination of the mandibular central incisor (P < 0.05).ConclusionChildren with Angle class III malocclusion treated with a Frankel III appliance showed no upper airway narrowing, even after repositioning the mandible posteriorly. Moreover, treatment promoted forward maxilla development and increased its width, in both the dental arch and alveolar bone, which provided a more harmonious craniofacial morphology.

Correlation between the upper airway volume and the hyoid bone position, palatal depth, nasal septum deviation, and concha bullosa in different types of malocclusion: A retrospective cone-beam computed tomography study.

The upper airway volume is among the factors that affect orthodontic treatment plans. Cone-beam computed tomography (CBCT), as an accurate diagnostic modality, can help assess anatomical structures associated with the upper airway volume. This study aimed to use CBCT to determine if there are differences in the upper airway volume between different sagittal and vertical skeletal patterns, considering the hyoid bone position, palatal depth, nasal septum deviation (NSD), and concha bullosa. From among 105 initial CBCT samples retrieved from the archive of a private radiology clinic in Tehran, Iran, 90 CBCT scans of 27 males and 63 females aged 17-65 years were considered in the study according to the inclusion criteria. The upper airway volume was assessed with regard to Angle's classification (using the A point-nasion-B point angle (ANB)), the vertical skeletal dimension (using the sella-nasion plane to mandibular plane angle (SN-MP)), the hyoid bone position, palatal depth, NSD, and concha bullosa, using CBCT and the NNT ® software. The one-way analysis of variance (ANOVA), Levene's test and the t test were used to analyze the data with the SPSS Statistics for Windows software, v. 17.0. The upper airway volume was significantly smaller in long-face cases (p = 0.037). There was no significant correlation between the upper airway volume and Angle's classification, the hyoid bone position, palatal depth, NSD, and concha bullosa. The vertical skeletal dimension was the only parameter that was related to the upper airway volume. The results of this study can be considered while preparing orthodontic treatment plans.

Effectiveness of Titratable Oral Appliance in Management of Moderate to Severe Obstructive Sleep Apnea-A Prospective Clinical Study with Acoustic Pharyngometry.

To assess effectiveness of titratable Oral Appliance (OA) in management of moderate to severe cases of Obstructive Sleep Apnea (OSA). Thirty Polysomnography (PSG) diagnosed cases of moderate to severe OSA were subjected to a thorough cranio-facial-dental evaluation, a detailed sleep history and three dimensional assessment of upper airway geometry utilising Acoustic Pharyngometry (AP) (Eccovision, sleep group solutions). A titratable OA was delivered to all patients for mandibular advancement. Apnea Hypopnea Index (AHI), Oxygen Saturation (SPO2), Epworth's Sleepiness Scale (ESS), Mean area and volume of upper airway were recorded at Baseline (T0) and after 08weeks of appliance delivery (T1). The mean AHI & ESS scores were significantly lower and SPO2 was significantly higher at T1 compared to T0 (P-value < 0.05 for all). The mean area and volume of upper airway at T1 were significantly higher compared to values at T0 (P-value < 0.05 for both). The mean area showed 19.51% increase at T1 whereas mean volume increased by 18.55%. OA therapy is highly efficacious in cases with moderate to severe OSA, especially, in those with retrognathic mandible. This modality should be considered as an effective alternate to Continuous Positive Airway Pressure (CPAP) therapy in non-compliant patients rather than no treatment. AP is an effective modality to predict airway changes after advancement with OA, to ascertain follow up changes and is highly recommended in routine clinical practice. Large scale, multicenter studies are recommended to elaborate the findings of the present study and to add better quality evidence in this regard.

Three-dimensional analysis of upper airway and craniofacial morphology in orthodontic adolescents with Attention Deficit Hyperactivity Disorder (ADHD): A comparative retrospective study

The aim of this study is to evaluate craniofacial characteristics and upper airway morphology in adolescents with Attention Deficit Disorder with Hyperactivity (ADHD) compared to controls (CON). Records from July 2014 to May 2018 of patients who were seeking orthodontic treatment at a single institute and had full pre-treatment orthodontic records including cone-beam computed tomography (CBCT) were reviewed. Comprehensive cephalometric variables were measured to determine craniofacial morphology. Upper airway volume (UAV), minimum cross-sectional area (MCA), and linear measurements were calculated at multiple planes. A total of 87 adolescents (ADHD, 29; CON, 58) were included in the study. Overall, UAV and MCA in ADHA group were smaller than CON. Statistical significance was evident in airway widths at planes A (P=0.002), C (P=0.042), and D (P<0.001), and airway area at plane D (lower hypopharynx) (P<0.001), with the ADHD group showing narrower widths and area compared to CON. The most common skeletal classification in the ADHD group was sequenced as Class II, Class I then Class III, with percentages of (58.6%), (31%) and (10.3%), respectively. No significant differences were found between the groups for any of the skeletal, dental, and soft tissue cephalometric variables. ADHD affected adolescents have similar craniofacial characteristics, but narrower upper airway dimensions compared to controls. Further investigations with larger samples are warranted to further elucidate the relationship between SDB and ADHD.

Cone beam CT evaluation of skeletal and nasomaxillary complex volume changes after rapid maxillary expansion in OSA children

ObjectiveThe first objective of this study was to evaluate skeletal changes and changes in dimensions and volume of the upper airways before and after rapid maxillary expansion (RME) therapy in children with obstructive sleep apnoea (OSA), by Cone Beam computed tomography (CBCT). The second objective was to evaluate if RME therapy could improve both the patency of the nasal airways and the Obstructive Sleep Apnoea Syndrome (OSAS). Methods19 children with OSA and malocclusion took CBCT scans with a Dentascan and 3D reconstruction program before (T0) and 4 months after (T1) RME. Patients underwent an ENT visit with auditory and respiratory tests, including a daytime sleepiness questionnaire, a 19-channel polysomnography, and an orthognatodontic examination before orthodontic therapy (T0), after 2 months (T1) with the device still on, and 4 months after the end of the orthodontic treatment (T2). ResultsIn all cases opening of the mid-palatal suture was demonstrated. Nasal osseous width, volume of the total upper airways, nasal cavity and nasopharynx and oropharynx increased significantly (P, .001). The increased W-ANS, W-mid and WPNS were closed linked to the enlarged midpalatal suture (P, .001). The increased WPNS were closed linked to the enlarged pterygoid processes (P, .001). The increased V-NC and V-NPA was closely linked to the enlarged W-PNS (P, .001) as well as VOPA and consequently to the enlarged midpalatal suture and pterygoid processes. ConclusionRME treatment had a positive effect on children affected by chronic snoring and OSA, causing an increase in volume of the nasal cavity and nasopharynx, with expansion of the nasal osseous width and maxillary width. Enlarged nasal width at the PNS plane contributed to the increase in nasopharynx volume. Enlarged maxillary width showed a direct correlation to increased airways volume, bringing a functional improvement. The results show that the RME therapy can restore and improve a normal nasal airflow with disappearance of obstructive sleep breathing disorder.

Are we able to predict airway dimensional changes in isolated mandibular setback?

The goal of this study was to determine whether a relationship exists between the amount of mandibular setback and the amount of airway dimensional changes. Records and cone beam computed tomography (CBCT) of patients who had undergone isolated bilateral sagittal split osteotomy setback between January 1, 2013 and March 16, 2020 at a single institution were reviewed retrospectively. The primary outcome variable was upper airway volume dimension change, and the predictor variable was the magnitude of mandibular setback as measured by six different methods. Thirty-one patients were included in the study, with a mean mandibular setback ranging from 1.41 mm to 6.11 mm. None of the predictor variables showed an association with oropharyngeal (P = 0.54) or hypopharyngeal (P = 0.33) volume. Stepwise regression analysis failed to show any significant relationships. Similarly, there was no statistically significant association between any of the predictor variables and oropharyngeal (P = 0.44) or hypopharyngeal (P = 0.74) minimum axial area. The results showed that no correlation exists between the magnitude of mandibular setback and the amount of static airway dimensional changes; therefore, it may not be possible to predict whether obstructive sleep apnea will develop following mild to moderate mandibular setback based upon CBCT measurements.

Volumetric magnetic resonance imaging analysis of multilevel upper airway surgery effects on pharyngeal structure.

The Sleep Apnea Multilevel Surgery (SAMS) trial found that modified uvulopalatopharyngoplasty with tonsillectomy (if tonsils present) combined with radiofrequency tongue ablation reduced obstructive sleep apnea (OSA) severity and daytime sleepiness in moderate-severe OSA. This study aimed to investigate mechanisms of effect on apnea-hypopnea index (AHI) reduction by assessing changes in upper airway volumes (airway space, soft palate, tongue, and intra-tongue fat). This is a case series analysis of 43 participants of 51 randomized to the surgical arm of the SAMS trial who underwent repeat magnetic resonance imaging (MRI). Upper airway volume, length, and cross-sectional area, soft palate and tongue volumes, and tongue fat were measured. Relationships between changes in anatomical structures and AHI were assessed. The participant sample was predominantly male (79%); mean ± SD age 42.7 ± 13.3 years, body mass index 30.8 ± 4.1 kg/m2, and AHI 47.0 ± 22.3 events/hour. There were no, or minor, overall volumetric changes in the airway, soft palate, total tongue, or tongue fat volume. Post-surgery there was an increase in the minimum cross-sectional area by 0.1 cm2 (95% confidence interval 0.04-0.2 cm2) in the pharyngeal airway, but not statistically significant on corrected analysis. There was no association between anatomical changes and AHI improvement. This contemporary multilevel upper airway surgery has been shown to be an effective OSA treatment. The current anatomical investigation suggests there are not significant post-operative volumetric changes associated with OSA improvement 6-month post-surgery. This suggests that effect on OSA improvement is achieved without notable deformation of airway volume. Reduced need for neuromuscular compensation during wake following anatomical improvement via surgery could explain the lack of measurable volume change. Further research to understand the mechanisms of action of multilevel surgery is required. This manuscript presents a planned image analysis of participants randomized to the surgical arm or the clinical trial multilevel airway surgery in patients with moderate-severe obstructive sleep apnea (OSA) who have failed medical management to assess change in OSA events and daytime sleepiness. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=266019&isReview=true%20Australian%20New%20Zealand%20Clinical%20Trials%20Registry%20ACTRN12514000338662, prospectively registered on March 31, 2014.

Dentofacial changes following treatment with a fixed functional appliance and their three-dimensional effects on the upper airway

Abstract Background Proposed skeletal changes achieved by functional appliances (FA) with reference to stable structures (structural method) have received relatively little attention compared to conventional cephalometric measurements (conventional method). Using the two methods, the aims of this study were to (1) determine the skeletal changes as a result of FA treatment; and (2) identify the skeletal changes associated with upper-airway volume and minimum cross-sectional area (MCA). Methods Pre- and post-treatment CBCT scans were selected from 73 FA treated children (37 girls and 36 boys; mean age 12.0 years) and 73 children as a control group (matched for chronological age, skeletal age, gender, and mandibular inclination) who received orthodontic treatment using only fixed appliances (no FA). Skeletal, upper-airway volume, and MCA changes were analysed by applying both structural and conventional methods. Results The FA group had significant skeletal effects compared with the control group (both methods; p = 0.04 – p &lt; 0.001). The horizontal displacement of pogonion (both methods) and the hyoid bone, together with a forward mandibular rotation (structural method), had positive effects on upper-airway volume and MCA (p &lt; 0.05). Conclusions The horizontal changes in pogonion (both methods) and the hyoid bone, as well as a forward mandibular rotation (structural method), have a strong association with changes in the upper airway. The conventional method underestimates FA treatment effects. These results may influence the management of growing class II patients with compromised upper airways.

Craniofacial Morphology and Upper Airway Dimensions in Patients with Hypermobile Ehlers-Danlos Syndrome Compared to Healthy Controls.

ABSTRACTObjectivesThe aims of the present case-control study were to compare craniofacial morphology, airway minimum cross-sectional area and airway volume between patients with hypermobile Ehlers-Danlos syndrome and healthy controls. Material and MethodsThe sample comprised 18 hypermobile Ehlers-Danlos syndrome (hEDS) patients (16 females, 2 males, mean age 34.1 [SD 10.35] years), clinically diagnosed and genetically tested in order to exclude other types of EDS, and 16 controls (14 females, 2 males, mean age 37.9 [SD 10.87] years) with neutral occlusion and normal craniofacial morphology. Craniofacial morphology was assessed on lateral cephalograms. Minimum cross-sectional area and upper airway volume were assessed on cone-beam computed tomography and analysed by standard and well-validated methods. Differences were tested by logistic regression analysis adjusted for age, gender and body mass index (BMI).ResultsNo significant differences in craniofacial morphology were found between hEDS patients and controls. Airway minimum cross-sectional area (P = 0.019) and airway volume (P = 0.044) were significantly smaller in hEDS patients compared to controls. When adjusted for age, gender and BMI no significant differences were found. However, minimum cross-sectional area was almost significant (P = 0.077). ConclusionsThe craniofacial morphology and airway dimensions of hypermobile Ehlers-Danlos syndrome patients were comparable to controls, with a tendency towards a smaller minimum cross-sectional area in the hypermobile Ehlers-Danlos syndrome group. The results may prove valuable for understanding the effect of hypermobile Ehlers-Danlos syndrome on craniofacial morphology and the upper airways.

Clinical impact of two types of mandibular retention devices - A CAD/CAM design and a traditional design - On upper airway volume in obstructive sleep apnea patients

ObjectiveThis pilot randomized crossover study evaluated the outcomes of two custom-made mandibular retention devices (MRDs), a computer-aided design (CAD)/computer-aided manufacturing (CAM) device (Narval CC™) and a non-CAD/CAM device (Narval™), on oropharyngeal airway volume in patients with obstructive sleep apnoea (OSA). Methods12 OSA patients were recruited from an University Hospital for MRD therapy with either CAD/CAM or non-CAD/CAM first. A cone-beam computed tomography evaluation (CBCT) and polysomnography assessment was performed during baseline assessment and at the end of each study period. ResultsUpper airway volume increased significantly with the CAD/CAM device (7725 +/- 6540 mm3, p = 0.008) but not with the non-CAD/CAM device (3805 +/- 7806 mm3, p = 0.13). The CAD/CAM device was also associated with a significant decrease in AHI (mean AHI after treatment 9.4±6.7 events/h, p = 0.003) and oxygen desaturation index (mean ODI of ≥ 3%/h 11.9 ± 6.8, p = 0.011). Changes in AHI (14.7 +/- 11.7 events/h, p = 0.083) and ODI (15.5 +/- 19.2, p = 0.074) were not statistically significant with the non-CAD/CAM device. The vertical dimension of occlusion increased significantly following treatment with both MRD devices (both p = 0.003), but was significantly less pronounced with the CAD/CAM device (mean difference: -2.7 +/- 1.7 mm, p = 0.003). Final mandibular protrusion after titration was the same with both devices (85%, p = 0.317). ConclusionThe CAD/CAM (Narval CCTM) device was associated with a significant increase in upper airway volume that may be caused by a lower degree of vertical separation between the jaws when compared to the non-CAD/CAM design.

The Usefulness of Modified Mallampati Score and CT Upper Airway Volume Measurements in Diagnosing OSA among Patients with Breathing-Related Sleep Disorders

Background: Obstructive sleep apnea (OSA) is a condition causing restriction of the airflow through the upper airways during sleep, despite preserved inspiratory muscle activity. This may lead to the development of secondary hypertension, ischemic heart disease, myocardial infarction, and arrhythmia. Moreover, the prevalence of OSA is on the rise. Methods: Comparison of scores from the Berlin Questionnaire, modified Mallampati scores (MMP), pulse oximetry readings and Upper Airway Volume (UAV) data obtained from CBCT (Cone Beam Computed Tomography). The study group of 129 patients of both sexes reporting sleep-related breathing problems completed the Berlin Questionnaire, had their oxygen saturation (SpO2) measured with a PO40 pulse oximeter, and oropharyngeal tissues assessed according to MMP. CBCT scans were put into 3D Amira TM 3D computer analysisto obtain UAV values. Results: Snoring was associated with significantly higher BMI compared to non-snoring patients. Furthermore, snoring patients had higher heart rate, modified Mallampati score, and lower UAV than the non-snoring group. The multifactorial analysis showed MMP as a useful indicator of the risk of snoring (OR = 7.468 (3863–14, 507, p &lt; 0.001)). Conclusions: The composition of MMP together with UAV and the Berlin questionnaire might be reliable indicators to assess the risk of snoring.

Craniofacial and Upper Airway Development in Patients With Treacher Collins Syndrome.

This study evaluated age-associated morphology changes in the cranial base, facial development, and upper airway of patients with Treacher Collins syndrome (TCS). A total of 33 preoperative computed tomographic images (TCS, n = 14; control, n = 19) were included in the study and divided into three age-related subgroups (2-6 years, 7-18 years, and older than 18 years). Linear, angular cephalometric measurements and upper airway volumes were collected. All measurements were analyzed using ProPlan CMF software (version 3.0; Materialize, Leuven, Belgium). The association between aging and upper airway morphology was analyzed. Compared to control subjects, TCS patients had a smaller cranial base, maxilla, and nose; they also had reduced upper airway volume compared to control subjects. The observed differences were most significant in patients between the ages of 7 and 18 years. This study used computed tomography-based three-dimensional analyses to provide a detailed description of age-related changes that occur in craniofacial measurements and upper airway volumes in children, adolescents, and young adult patients with TCS in China. These data can be used to evaluate individual patients with TCS and to select treatment to improve the growth of the craniofacial region.

Eccentric movements of temporomandibular joint and upper airway volume: Three-dimensional segmentation using cone beam computed tomography

ABSTRACT Objective The purpose of the present investigation was to assess whether possible changes in the dynamic movements of the TMJ might cause a greater variation between the volumes of the upper airways in open- and closed-mouth positions. Methods CBCT scans of 92 subjects were used to assess the TMJ bilaterally. All scans were acquired in closed (CM) and maximum mouth opening (MMO) positions. The difference in the volume of the oropharyngeal cavity obtained by subtracting the CM volume from the MMO volume (delta volume or volume variation) was calculated. The resulting volume was analyzed by Mann-Whitney test for variation in rotation. Results A significant difference was found (p-value = 0.0188) on the right side regarding changes in the rotational movement of the condyle (Mann–Whitney test). Conclusion This study showed a relationship between degree of abnormal or limited rotation and variation in the upper airway volume on one side.