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 upper airway anatomy and Sella turcica morphology across different skeletal malocclusions: a computerized technique

ObjectiveThis study aimed to investigate the normal volumetric space and variations in the measurements of different landmarks in adults with different skeletal relations of the maxilla and the mandible based on CBCT data. The study also analyses these landmarks to locate any correlations.BackgroundNumerous studies in orthodontics have found a relationship between orthodontic treatment and changes in the anatomy and function of the airway. Severe changes in airway morphology can cause breathing difficulties, lower quality of life, and even result in life-threatening conditions such as obstructive sleep apnoea. Consequently, orthodontic diagnosis and treatment planning require a thorough understanding of the airway space and its function.MethodsThe present retrospective study was conducted using CBCT records of 120 adult patients, containing 40 samples of each skeletal class (20 males and 20 females). The boundaries were defined for the 3 major regions: the nasopharynx, the oropharynx, and the hypopharynx. Various measurements were recorded across these regions, as well as selective cephalometric landmarks. The obtained data was used to calculate average and standard deviation, while regression analysis was used to evaluate correlations and t-test was used to test statistical significance of gender differences.ResultsThe results demonstrate that skeletal Class III individuals exhibit a reduced airway volume in the nasopharynx compared to other groups, whereas skeletal Class II individuals displayed a diminished airway volume in the hypopharynx. A strong correlation was observed for Sella turcica parameters. There were no significant differences in skeletal parameters across genders. Nasopharynx cavity volume demonstrated significant differences between skeletal Class I–Class III as well as between skeletal Class II–Class III. Hypopharynx cavity volume also demonstrated significant differences between skeletal Class I–Class II and between skeletal Class II–Class III.ConclusionThe major findings are the presence of a reduced nasopharyngeal volume in skeletal Class III malocclusions while skeletal Class II individuals displayed a diminished hypopharyngeal volume, making these critical areas to consider during the diagnostic and orthodontic treatment planning stages. This study also revealed a consistent correlation between Sella turcica parameters across various facial skeletal profiles, with skeletal Class II patients exhibiting a distinct pattern and skeletal Class I and Class III demonstrating an average relationship.

Correlation analysis of airway space and condylar morphology in bilateral idiopathic condylar resorption patients.

To evaluate the airway space in bilateral idiopathic condylar resorption (ICR) patients and analyse the correlation between the morphological characteristics of the condyles and airway parameters. In all, 35 female patients with bilateral ICR (mean age: 21.6 years) and 35 age-matched female controls (mean age: 21.3 years) were included. Airway parameters were measured using CBCT. Independent T-tests were used to analyse the differences between the bilateral ICR group and the control group, and then the correlation between airway parameters and condylar parameters was detected using Pearson correlation analysis. p < .05 was considered statistically significant. Patients with bilateral ICR showed a significant decrease in airway volume, minimum axial area and sagittal sectional area (p < .05). The bilateral condylar axial angle positively correlated with airway volume and sagittal sectional area (p < .05). In contrast, the bilateral condylar neck angle negatively correlated with sagittal sectional area (p < .05). None of the condylar parameters showed a correlation with minimum axial area of the airway in the bilateral ICR group (p > .05). Bilateral ICR significantly affects patients' airway space. The condylar axial angle and neck angle correlate with airway parameters.

Cephalometric differences in grades II and IV adenoid hypertrophy: A cross-sectional study.

This study aims to determine whether there were cephalometric changes between grades II and IV adenoid hypertrophy. A cross-sectional study was conducted on 120 6-12-year-old patients selected from the ear, nose, and throat department at Imam Al-Hussein Medical City in Karbala. Patients were classified into three groups (each = 40) based on endoscopic findings: control, grade II, and grade IV. The findings were confirmed with cephalometric radiographs. Specific cephalometric points were identified to measure sella-nasion-point A (SNA), sella-nasion-point B (SNB), point A-nasion-point B (ANB), sella-nasion-pogonion (SNPog), sella nasion plane-palatal plane (SNPP), palatal plane-mandibular plane (PPMP), sella nasion plane-mandibular plane (SNMP), saddle, articular, gonial angles, and the y-axis. Additionally, superior-posterior airway space (SPAS), posterior air way space (PAS), mandibular plane-hyoid bone (MP-H), third cervical vertebra-hyoid bone (C3-H), total anterior facial height (TAFH), total posterior facial height (TPFH), upper anterior facial height (UAFH), lower anterior facial height (LAFH), and the Jarabak ratio were measured. Analysis of variance (ANOVA) and Welch tests indicated statistically significant differences (P < 0.05) among the three groups in SNA, SNB, SNPog, PPMP, SNMP, gonial angle, y-axis, SPAS, PAS, MP-H, and the Jarabak ratio. Tukey's honestly significant difference (HSD) and Games-Howell tests indicated a statistically significant difference between grade II and grade IV in SNA, SNMP, y-axis, SPAS, PAS, MP-H, and Jarabak ratio. The present study demonstrated that craniofacial changes start to occur at the moderate adenoid enlargement throughout the downward backward mandibular rotation. More changes would become evident at the severe stage; therefore, an urgent medical intervention and the establishment of nasal breathing by orthodontic treatment with breathing activity would be needed.

Performance enhancement of deep learning based solutions for pharyngeal airway space segmentation on MRI scans

The automatic segmentation of the pharyngeal airway space has many potential medical use, one of which is to help facilitate the creation of the Tubingen Palatal Plate. Therefore, it is of great importance to understand which methods are suitable for this task. Here, neural network based solutions available in the literature are compared to find the best methods. Neural network models were chosen to encompass a diverse landscape. Some models were taken from the general semantic segmentation literature, while others were taken from the medical or pharyngeal airway space segmentation literature. Some models are convolutional neural networks, while others are transformer-based model or a mix of both convolutional and transformer-based model. These models include 2d/3d U-Net, Deeplabv3, YOLOv8, Swinv2 UNETR, SegFormer, and 3D MRU-Net. Furthermore, additional strategies to enhance performance were also considered. These strategies consisted of training two separate networks in multiple stages as well leveraging unlabeled data to pretrain the neural networks before fine-tuning them on the labeled data. It was found that out of all the models considered here, the 2d U-Net performed the best achieving an average dice score of 0.9180 ± 0.0111. Out of all the strategies to enhance performance, only two strategies improve the actual results but only by a small margin. Therefore, these strategies can be consider if a small increase in performance is desired from the 2d U-Net at the expense of computational resource.

Three-dimensional analysis of palatal morphology and PAS in patients with cleft lip and palate prior to orthodontic treatment

BackgroundSince many different conclusions of craniofacial anomalies and their relation to the posterior airway space coexist, this comparative clinical study investigated the palatal morphology concerning volumetric size, posterior airway space dimension and the adenoids of patients with and without a cleft before orthodontic treatment.MethodsThree-dimensional intraoral scans and cephalometric radiographs of n = 38 patients were used for data acquisition. The patients were divided into three groups: unilateral cleft lip and palate (n = 15, 4 female, 11 male; mean age 8.57 ± 1.79 years), bilateral cleft lip and palate (n = 8, 0 female, 8 male; mean age 8.46 ± 1.37 years) and non-cleft control (n = 15, 7 female, 8 male; mean age 9.03 ± 1.02 years). The evaluation included established procedures for measurements of the palatal morphology and posterior airway space. Statistics included Shapiro-Wilk-Test and simple ANOVA (Bonferroni) for the three-dimensional intraoral scans and cephalometric radiographs. The level of significance was set at p < 0.05.ResultsThe palatal volume and cephalometric analysis showed differences between the three groups. The palatal volume, the superior posterior face height and the depth of the bony nasopharynx of patients with cleft lip and palate were significantly smaller than for non-cleft control patients. The superior posterior face height of bilateral cleft lip and palate patients was significantly smaller than in unilateral cleft lip and palate patients (BCLP: 35.50 ± 2.08 mm; UCLP: 36.04 ± 2.95 mm; p < 0.001). The percentage of the adenoids in relation to the entire nasopharynx and the angle NL/SN were significantly bigger in patients with cleft lip and palate than in the non-cleft control. In particular, the palatal volume was 32.43% smaller in patients with unilateral cleft lip and palate and 48.69% smaller in patients with bilateral cleft lip and palate compared to the non-cleft control.ConclusionsSkeletal anomalies relate to the dimension of the posterior airway space. There were differences among the subjects with cleft lip and palate and these without a cleft. This study showed that the morphology of the palate and especially transverse deficiency of the maxilla resulting in smaller palatal volume relates to the posterior airway space. Even the adenoids seem to be affected, especially for cleft lip and palate patients.

Triad of temporomandibular joint ankylosis, micrognathia, and obstructive sleep apnoea: a systematic review of surgical management

Complex functional issues arising from temporomandibular joint (TMJ) ankylosis are associated with abnormal mandibular growth secondary to the condylar-glenoid fossa and its surrounding structures. These include severe limited mouth opening, micrognathia, mandibular asymmetry, and obstructive sleep apnoea (OSA), which necessitate effective treatment to allow optimum functional rehabilitation. This article aims to present a comprehensive systematic review of the surgical strategy for patients who present with a triad of TMJ ankylosis, micrognathia and OSA via a literature search of PubMed, Google Scholar, and Scopus following PRISMA guidelines. The outcomes of interest were difference in maximum mouth opening, incidence of reankylosis, amount of mandibular advancement, posterior airway space, preoperative and postoperative apnoea/hypopnoea index, and arterial oxygen saturation, as well as changes in other cephalometric or polysomnographic variables. Thirty four studies involving 360 patients were included. Surgical interventions included distraction osteogenesis (DO), release of TMJ ankylosis and mandibular advancement, simultaneous arthroplasty and DO, pre-athroplasty DO, and post-arthroplasty DO. Most studies reported functional post-intervention mouth opening, with reankylosis reported in four. Mandibular advancement was between 6 mm and 34 mm. All studies reported improvement in the various polysomnographic variables measured. In conclusion, the systematic review was conducted based on a low level of literature evidence. Even though various surgical strategies were reported, effective case-specific management of TMJ ankylosis with micrognathia and OSA requires comprehensive assessment and careful consideration of surgical options that promote mandibular advancement and airway improvement.

Correlation between the three-dimensional hyoid bone parameters and pharyngeal airway dimensions in different sagittal and vertical malocclusions

ObjectiveThis study aimed to explore the relationship between three-dimensional (3D) measurements of the hyoid bone (HB) and pharyngeal airway space (PAS) in relation to sagittal and vertical malocclusion. MethodsA total of 368 cone-beam computed tomography (CBCT) scans were classified into three skeletal groups (Class I, II, and III) and subdivided by vertical growth patterns (hypodivergent, normodivergent, and hyperdivergent). PAS dimensions, including nasopharyngeal, oropharyngeal, hypopharyngeal, and total airway spaces, were measured in surface area, volume, minimum constricted area (MCA), length, and width, HB position and dimension were analyzed in 3D using InVivo 6.0.3 and Dolphin 11.8 software. Data were analyzed using two-way ANOVA, and Bonferroni post-hoc tests, with P ≤ 0.05 considered significant. ResultsThe study found that patients with skeletal Class III and hypodivergent growth pattern had the highest sagittal position of the hyoid bone, while those with skeletal Class II and hyperdivergent pattern had the lowest hyoid length. Nasopharyngeal airway space width was significantly lower in skeletal Class III patients, while volume and area were lower in hyperdivergent patients. Oropharyngeal and hypopharyngeal dimensions were also affected by skeletal class and growth pattern, with hyperdivergent patients having the lowest values. Total pharyngeal volume, area, and minimum constricted area were also affected, with hyperdivergent patients having the lowest values and skeletal Class II patients having the lowest minimum constricted area. ConclusionPharyngeal airway dimensions and hyoid bone parameters vary with malocclusions. The hyoid bone's position influences the airway, identifying patients at risk for airway obstruction and sleep-disordered breathing.

Orthognathic surgery improves compromised natural head position and pharyngeal airway in patients with Skeletal Class II or III malocclusion.

Natural head position (NHP), pharyngeal airway and maxillofacial growth pattern are correlated. The author's previous studies proved that following surgical correction of Skeletal Class II malocclusion, the over-extended NHP returned upright, and the pharyngeal airway space (PAS) dimension expanded. The present study compares the post-operative change in NHP and PAS after orthognathic surgery in Skeletal Class II and III malocclusion patients. Patients receiving orthognathic procedures to correct Skeletal Class II or III malocclusions were reviewed in this retrospective study. Pre-operative and 6-week post-operative cone-beam computed tomography datasets were collected. Variables representing the craniofacial pattern, the NHP and the PAS were measured three-dimensionally. Post-operative variables were compared with their pre-operative counterparts using either repeat-measure 2-way analysis of variance or Wilcoxon matched-pairs signed rank test. Thirty cases of Skeletal Class II malocclusion and 13 cases of Skeletal Class III malocclusion were collected. Preoperatively, the inter-group differences were significant in craniofacial pattern (68.14 ± 3.552 degree vs. 79.63 ± 2.497 degree, p < .0001) and the NHP (68.77 ± 11.02 degree vs. 82.83 ± 7.738 degree, p = .0002) while not significant in PAS; after surgery, the intergroup differences in craniofacial pattern and the NHP between groups decreased, and the PAS increased in both groups. Orthognathic surgery may improve compromised NHP and increase PAS in Skeletal Class II and III malocclusion patients.

Developmental Changes in Pharyngeal Airway in the Male Population From Adolescence to Adulthood.

During adolescence, there is a significant surge in height and total body mass of males. Consequently, they simultaneously experience enhancements in their circulatory and respiratory systems, which adapt to these physiological transformations. The purpose of present study was to investigate the developmental changes in male pharyngeal airway from adolescence to adulthood. Lateral cephalograms of 192 males were obtained and divided into 5 groups: early adolescence (age 10-13 years), middle adolescence (age 14-17 years), late adolescence (age 18-21 years), early adulthood (age 22-30 years), and middle adulthood (ages 31-50 years). The dimensions of pharyngeal airway spaces and the related anatomical structures were investigated. The one-way analysis of variance and Pearson correlation analysis were employed for statistical analysis. During middle adolescence, the pharyngeal airway seems to be nearly completed in males. A significant negative correlation was found between the ANB angle and SPS, TPS, and EPS values.

Airway Analysis in Different Malocclusions - A Cephalometric Study

Background: It was essential to evaluate respiratory function when diagnosing and planning orthodontic treatment. Based on the correlation between pharyngeal airway space and craniofacial structure, airway width was hypothesized to be an indicator of airway patency in different groups of skeletal malocclusion. Aim: The purpose of this study was to investigate age and gender related changes in pharyngeal airway dimensions in different sagittal skeletal relationships Materials and Method: Sixty lateral cephalograms of patients aged 10-30 years with no pharyngeal pathology or nasal obstruction were retrospectively selected and categorized into skeletal Class I (n = 20), Class II (n = 20), and Class III (n = 20) malocclusion based on ANB angle. McNamara's airway analysis was used to quantify upper- and lower-airway dimensions. The analyses of intergroup differences were performed using a one-way ANOVA, an independent t-test, and Tukey's test as a post-hoc test. Results: Participants in the study ranged in age from 20.57 ± 5.41 years (males) and 20.03 ± 4.58 years (females) were included in the study. The upper pharyngeal airway (UPA) dimensions demonstrated a positive correlation with age. In both genders, the mean upper pharyngeal airway (UPA) size exceeded the lower pharyngeal airway (LPA) size, but neither age nor gender was associated with statistically significant differences in skeletal malocclusion. Conclusion: It was shown that skeletal malocclusions of different types have no effect on the upper and lower pharyngeal airways and that the upper and lower pharyngeal airways are not influenced by age or gender.

Cephalometric Screening Assessment for Superior Airway Space Narrowing-Added Value of Three-Dimensional Imaging.

Background: Assessing the morphology of the superior airway space is a crucial diagnostic step in the treatment planning of patients with obstructive sleep apnea syndrome (OSAS) or prior to orthognathic surgery. The aim of this study is to evaluate the necessary scope of a two-dimensional cephalometric assessment and the necessity of three-dimensional imaging in the identification of superior airway space narrowing (SASN). Methods: The computed tomography studies of 100 non-obese, non-OSAS patients were evaluated and analyzed retrospectively. Multiplanar reconstructions were created and underwent cephalometric evaluation. The three-dimensional superior airway morphology was segmented and measured for the minimal cross-sectional area (Amin) and volume (V0). Patients were grouped according to Amin < 80 mm2 and V0 < 12 cm3. Cephalometric parameters (CPs) were analyzed according to Amin and V0 with an unpaired t-test, Pearson correlation, and ROC-curve analysis. Results: The CPs regarding sagittal airway space dimensions (IPAS, MPAS, SPAS) and mandibular body length (GoGn) show the strongest correlation to the three-dimensional minimal cross-sectional area (Amin). The ROC-curve analysis classifying for SASN led to an AUC of 0.86 for IPAS, 0.87 for MPAS, 0.88 for SPAS, and 0.63 for GoGn. Three-dimensional imaging may further improve the diagnostic accuracy in the identification of SASN for IPAS below 13.5 mm, MPAS below 10.2 mm, SPAS below 12.5 mm, and GoGn below 90.2 mm. Conclusions: Two-dimensional cephalometric sagittal airway space diameters and mandibular body length are useful initial screening parameters in the identification of superior airway space narrowing. Nevertheless, as the correlation of two-dimensional cephalometric parameters with three-dimensional upper airway space narrowing is varying and highly dependent on acquisition circumstances, indications for three-dimensional imaging, if possible, in the supine position to evaluate upper airway space morphology should be provided generously, especially in patients with low but normal airway space parameters in two-dimensional cephalometry.

Recruitment of T-cells to the lung using an ex vivo co-culture paradigm

Precision cut lung slices (PCLS) bridge a gap between in vivo and in vitro studies by maintaining anatomical organization with structural integrity and intercellular signaling pathways. Applications of PCLS have included the modeling of inflammatory lung diseases, metabolism studies, and drug development. In the lungs, immune responses are carried out by a network of T- and B- cells, the latter of which are resident. The limited resident T-cell population of the lung diminishes accurate representations of pathogen response capacity in PCLS. Addressing this, we set out to increase pulmonary T-cell populations ex vivo. We hypothesized that thymus and bone marrow-derived T-cells would work synergistically to populate the lung in co-culture experiments. A murine organotypic lung co-culture model was developed and characterized for tissue health and T-cell recruitment over 3 days ex vivo using adult neurobasal media with 4 mM glucose + 2% B27 supplement. Lung slices were cultured independently, with bone marrow, thymus, or both. Immune colonization of the lung was assessed using immunohistochemistry for CD3+ T-cells and ACK2+ cells. Cells were counted in alveolar and airway spaces after 3 days of culture. Co-culture of lung slices with bone marrow did not increase CD3+ immunoreactive T-cells while thymus co-culture increased CD3+ T-cells by 76% in the alveolar space and by 39% in the airway, relative to lung alone. When lung slices were cultured with bone marrow plus thymus, CD3+ T-cells increased by 206% in the alveolar space and by 251% in the airway, relative to the lung alone. Co-culture with thymus increased ACK2+ cells by 48% in the airway, while lung culture with both thymus and bone marrow, ACK2+ cells increased by 35% in the alveolar space and 85% in the airway, relative to the lung alone. These results suggest that the increased T-cell population corresponding with thymus and bone marrow co-culture could be a result of cell-cell interaction or the secretion of growth factors. Cell secretions or growth factor release could stimulate thymic secretion of T-cells or could stimulate T-cell proliferation in the lung, suggesting that co-culture with thymus and bone marrow can elicit a T-cell response ex vivo. Future studies will center around differentiating what drives T-cell population to be increased in lung co-cultures and what T-cell subsets are being recruited in PCLS co-cultures while analyzing their capacity for response to pathogens ex vivo. Anschutz Foundation Pandemic Preparedness Grant. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

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

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

Comparison of PAS and adenoids in patients with and without maxillary micrognathia before orthodontic treatment

ObjectiveCraniofacial anomalies are widely discussed as predisposing factors of breathing disorders. Since many more cofactors exist, this study investigated the association between maxillary micrognathia and morphological changes of posterior airway space and adenoids in these patients.Material and methodsCephalometric radiographs of n = 73 patients were used for data acquisition. The patients were divided into two groups according to certain skeletal characteristics: maxillary micrognathia (n = 34, 16 female, 18 male; mean age 10.55 ± 3.03 years; defined by a SNA angle < 79°) and maxillary eugnathia (n = 39, 19 female, 20 male; mean age 10.93 ± 3.26 years; defined by a SNA angle > 79°). The evaluation included established procedures for measurements of the maxilla, posterior airway space and adenoids. Statistics included Kolmogorov–Smirnov-, T- and Mann–Whitney-U-Tests for the radiographs. The level of significance was set at p < 0.05.ResultsThe cephalometric analysis showed differences in the superior posterior face height and the depth of the posterior airway space at palatal level among the two groups. The depth of the posterior airway space at mandibular level was the same for both groups, just as the size of the area taken by adenoids in the nasopharynx.ConclusionsSkeletal anomalies affect the dimension of the posterior airway space. There were differences among the subjects with maxillary micrognathia and these with a normal maxilla. However, the maxilla was only assessed in the sagittal direction, not in the transverse. This study showed that the morphology of the maxilla relates to the posterior airway space whereas the adenoids seem not to be affected.Clinical relevanceMaxillary micrognathia is significantly associated with a smaller depth of the posterior airway space at the palatal level compared to patients with maxillary eugnathia.

Assessing the Accuracy of Lateral Cephalogram in Quantifying Three-Dimensional Pharyngeal Airway Morphology Compared to Cone-Beam Computed Tomography.

When it comes to orthodontic diagnosis and treatment planning, the structures of the upper and lower airway spaceare crucial because of therole they play in craniofacial development. The major objective of this study was to evaluate the accuracy of lateral cephalogram in the evaluation of upper and lower pharyngeal space by comparing it to clinical usage of cone-beam computed tomography (CBCT) in quantifying the 3D morphology of the pharyngeal airway. In total, 70 patients were included in the study. They had both a CBCT scan and a lateral cephalogram performed within a week of each other. Different cephalometric landmarks have been utilized to estimate linear and area dimensions for use in lateral cephalogram airway investigations. By superimposing the lateral cephalogram measurement of the vertical height of the pharyngeal airwayover axial CBCT slices of 0.8 to 1 mm in thickness, airway volumes were calculated. For this study, we measured the pharyngeal airway space in each patient in two dimensions (2D) using the airway area from the lateral cephalogram and in three dimensions (3D) using the airway volume from the CBCT scan over the same region of interest, using a uniform scale and magnification throughout all split 3D volumes. The mean value of the area of pharyngeal space calculated by lateral cephalograph analysis (LCA) was 336.35 ± 86.49 mm2. The maximum value was 551.234 mm2. The minimum value was 206.32 mm2. The mean value of the volume of the same area calculated using CBCT was 3409.11 ± 1237.96 mm3. The maximum value was 5887.23 mm3. When the area calculated using LCA was compared with the volume calculated using CBCT, the correlation between them was significant statistically(r=0.831, p-value =0.000). The mean values of volume evaluated in 3D CBCT in males were 4198±1008 mm3 while for females it was 2980±1134.5 mm3. During the statistical analysis,these observations were found to have a positive correlation with increased volume of pharyngeal space in males as compared to that of females (p=0.006). The values of the area of pharyngeal space calculated using LCA in males was 370.1±60.9 mm2. while it was 301.9±88 mm2 in females. The area estimated for the pharyngeal airway on LCA correlates strongly with the volume determined by a CBCT scan. Since we have considered pharyngeal space analysis using CBCT to be a reliable and standard methodology, therefore a positive correlation of area calculated using LCA with volume calculated using CBCT shows that the analysis made by LCA can be reliable.

Assessment of pharyngeal airway space in patients with different maxillofacial skeletal abnormalities using cone beam computed tomography

Background. The patency of the pharyngeal airway has a far-reaching impact on craniofacial development. Conversely, the position of the maxillofacial skeletal components in certain disorders may lead to a compromised airway. Therefore, the evaluation of the airway is an essential step in treatment planning. Objectives. The basic aim of this study was to measure the pharyngeal air space volume in the patients with maxillofacial skeletal abnormalities (like Class II, Class III malocclusion, TMJ Ankylosis, Condylar abnormalities and Syndromic cases) and those without any skeletal abnormalities. The objectives were to assess the Linear, Cross-sectional, and Volumetric dimensions of the pharyngeal airway in patients with and without maxillofacial skeletal abnormalities. (Study and Control group) Materials and methods. The Study group included 49 patients with maxillofacial Skeletal abnormalities like Class II and Class III malocclusion, Temporomandibular Joint Ankylosis, Condylar abnormalities, Syndromic cases. 49 Control group patients did not present with any skeletal abnormalities. The Linear, Cross-sectional, and Volumetric dimensions of the pharyngeal airway in the Study group and Control group were calculated and compared within the groups. Statistical Analysis: Unpaired t -test, ANOVA test and Tukey’s Post Hoc analysis test were for the data analysis of the above study. Outcomes. The Anteroposterior dimension of the airway at the Superiormost level was found to be significantly greater in Class II (p-value-0.039), Class III (p-value-0.002), and Control groups (p-value &lt;0.001) when compared with the TMJ Ankylosis group. The Volume and Cross-sectional area of the airway at the most constricted level of the airway was found to be significantly greater in Class III (p-value &lt;0.001) and Control group (p-value 0.013, 0.003) respectively when compared with the TMJ Ankylosis group. Conclusions. The pharyngeal airway was narrowest anteroposteriorly at all three levels (Superior-most, Most constricted, and Inferior-most levels) in the TMJ Ankylosis group and widest in the Class III group. The least cross-sectional area was found in the TMJ Ankylosis group whereas the greatest was found in the Class III group. The airway volume in the TMJ Ankylosis group and Class II group is significantly lesser than that of the Control group.

Role of Sensory Nerves in Pulmonary Fibrosis.

Pulmonary fibrosis results from the deposition and proliferation of extracellular matrix components in the lungs. Despite being an airway disorder, pulmonary fibrosis also has notable effects on the pulmonary vasculature, with the development and severity of pulmonary hypertension tied closely to patient mortality. Furthermore, the anatomical proximity of blood vessels, the alveolar epithelium, lymphatic tissue, and airway spaces highlights the need to identify shared pathogenic mechanisms and pleiotropic signaling across various cell types. Sensory nerves and their transmitters have a variety of effects on the various cell types within the lungs; however, their effects on many cell types and functions during pulmonary fibrosis have not yet been investigated. This review highlights the importance of gaining a new understanding of sensory nerve function in the context of pulmonary fibrosis as a potential tool to limit airway and vascular dysfunction.

Effect of the Mandibular Repositioning Appliance (MARA) on Posterior Airway Space (PAS)

Aim of the study was to show the effect of skeletal Class II treatment with the mandibular anterior repositioning appliance (MARA) on the sagittal posterior airway space (PAS) diameter. A total of 53 patients were selected retrospectively: 26 male patients (median 13 years, age span 10–19 years) and 27 female patients (median 14 years, age span 11–47 years). All patients had lateral cephalograms taken at T1 (before MARA treatment) and at T2 (after MARA treatment). Average treatment took 13.1 ± 7.5 months (Group 1) and 10.5 ± 4.5 months (Group 2), respectively. The following PAS parameters were obtained at T1 and T2: TI (Tangent Point 1), Me/Gn (menton/gnathion), DW (dorsal wall). Additionally, Björk‘s sum angle, SNA, SNB and ANB were determined. The male patients showed a higher increase in the anteroposterior diameter of the PAS (+27.5%) compared to female patients (+11.6%). Male participants had a significantly higher PAS (p = 0.006) than female participants (p = 0.09). Although not significantly, Björk‘s sum angle decreased in both groups. In general, compared to female patients, male patients showed a greater decrease between T1 and T2. SNA and SNB exhibited varied behavior between T1 and T2, with some individuals reporting a decrease and others reporting an increase. SNA tended to decrease in general. In terms of ANB, the male participants displayed a decrease from T1 to T2. Treatment of a skeletal Class II malocclusion with the mandibular anterior repositioning appliance (MARA) caused an increase in the sagittal posterior airway space (PAS) diameter and, thereby, might be effective against obstructive sleep apnea.

The effect of tongue reduction for preventing adverse effects in patients undergoing class III orthognathic surgery: a three-dimensional comparative analysis.

This study aims to evaluate the potential benefits of combining tongue reduction with mandibular setback surgery in patients undergoing class III orthognathic surgery. Specifically, we investigated whether this combined approach reduced the risk of surgical relapse, condylar resorption, and airway space reduction by mitigating tongue pressure on the mandible. The study retrospectively enrolled patients who had undergone bilateral sagittal split ramus osteotomy (BSSRO) with at least 5 mm of setback and met the criteria of a body mass index > 20 kg/m2 and tongue volume > 100 mm3. The study included 20 patients with 10 in the tongue reduction group (TR, n = 10) and 10 in the BSSRO only group (SO, n = 10). The volumetric changes of the total airway space were significantly different between the TR and SO groups (p = 0.028). However, no significant differences were observed in the condylar resorption and postoperative relapse between the groups (p = 0.927 and 0.913, respectively). The difference between the resorption of the anterior and posterior segments of the condyle was also statistically insignificant (p = 0.826). Postoperative counterclockwise rotation of the proximal segment only demonstrated a significant correlation with postoperative relapse (p = 0.048). The reduction in tongue volume demonstrated a preventive effect on the reduction of the airway space after mandibular setback, although it did not yield statistical significance concerning surgical relapse and condylar volume. The counterclockwise rotation of the proximal segment might be responsible for the forward displacement of the distal segment and postoperative relapse. However, the clinical implications of this finding should be interpreted with caution owing to the limited sample size CLINICAL RELEVANCE: Tongue reduction could potentially serve as a preventive measure in preserving the airway space and might be beneficial in mitigating the risk of obstructive sleep apnea in patients with class III deformity.