Airway In Class Research Articles

Risk of Narrow Upper Airway in Class II Children with Large Horizontal Maxillary Overjet Assessed By Acoustic Reflection: a Case-Control Study

Risk of Narrow Upper Airway in Class II Children with Large Horizontal Maxillary Overjet Assessed By Acoustic Reflection: a Case-Control Study

Correlation of Palatal Index With Pharyngeal Airway in Various Skeletal Patterns.

Introduction This retrospective study aimedto correlate palatal index with pharyngeal airway in class I, class II and class III skeletal patterns. Materials and methods A total of 30 individuals with a mean age of 17.5 years were included in the study. The subjects were categorized on the basis of ANB (A point, nasion, B point) angle into skeletal class I, II, and III patterns (N=10). Using Korkhaus analysis, palatal height, palatal breadth, and palatal height index were calculated from the study models. From the lateral cephalogram, the dimensions of the upper and lower pharyngeal airways were measured using McNamara Airway Analysis. The results were calculated using the ANOVA test. Results A statistically significant difference was found in all three groups of class I, II, and III malocclusions for palatal index and airway dimensions. The skeletal class II malocclusion participants exhibited the highest mean values for the palatal index (P=0.03). Class I had the highest mean value for the upper airway (P=0.041), whereas class III had the highest mean value for the lower airway (P=0.026). Conclusion It was concluded that subjects with the class II skeletal pattern have a high palate and reduced upper and lower airways when compared with class Iand class III skeletal patterns, which showed larger upper and lower airways, respectively.

Evaluation of changes in tongue pressure with twin-block appliance therapy in growing Class II Div 1 malocclusion. An in vivo study.

Twin-block appliance therapy in patients with Class II Div 1 malocclusion positions the mandible anteroinferior leading to possible alterations in tongue pressure, tongue length, and the oropharynx. To evaluate the changes in tongue pressure, tongue length and dimension of the pharyngeal airway in Class II Division 1 subjects before and after twin-block therapy. Twenty-four subjects were selected, in the range of 10-14 years (mean-12 years). The tongue pressure was recorded at three regions with sensors placed at the incisive papilla and bilaterally at the molar region of the palate for four minutes. The root mean square (RMS) values were recorded and used for further analysis. Evaluation of tongue length and pharyngeal airway dimension was done using a lateral cephalogram. All the measurements were done before and after twin-block appliance therapy. The paired t-test was performed to compare the changes. Resting tongue pressures decreased from pre-treatment levels to post-treatment at all three regions. Change in ANB angle was found to have a significant negative correlation with tongue length, and pharyngeal airway dimension, a significant positive correlation with pressure at incisive papilla and left molar region and no correlation at right molar region. There was a decrease in resting tongue pressure as the malocclusion was corrected from Class II to Class I. Hence, this decrease in pressure could be a contributory factor in the maintenance of the dental equilibrium as lighter forces exist in the oral cavity.

Temporomandibular Joint Disorder and Airway in Class II Malocclusion: A Review.

In class II malocclusion, there is an anteroposterior disparity between the upper dentition and the lower dentition, which may or may not be accompanied by a skeletal discrepancy. For orthodontists, this is one of the common malocclusions encountered during clinical practice. This might be due to excess maxillary growth or retarded growth of the mandible or a combination of both. In such types of malocclusion, both the upper and lower airways are affected, the lower one most commonly. Characteristic features seen are a narrow maxillary arch, a proclined upper anterior, and mouth breathing as a developing habit. Also, the position of the condyle in the skeletal type of class II malocclusion plays a vital role in the development of temporomandibular joint disorders. Treating such disparity in a growing individual leads to better results in the long term as well as prevention of malocclusion taking a severe form. Myofunctional appliances are useful for repositioning the mandible as well as the condyle. In adults, extraction of the upper premolars is most commonly done for the correction of class II malocclusion. This provides the patient with a better esthetic appearance.In addition to this, various treatment modalities, such as splint therapy, exercise, and prolotherapy, are beneficial for pain relief and temporomandibular disorder (TMD) correction. This article deals with the characteristics, development, etiology, and comprehensive treatment options of class II malocclusion and its co-relation with the upper and lower airway along with the severity of temporomandibular joint disorders. Repositioning of the condyle in the glenoid fossae is the key to the correction of this disorder.

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.

Determining the short-term effects of different maxillary protraction methods on pharyngeal airway dimensions.

This study sought to evaluate the effects of different maxillary protraction methods on the pharyngeal airway in Class III patients with maxillary retrognathia. A total of 59 individuals (31 females and 28 males) with a mean age of 11.38±1.24years were included in this study. Fifty-nine treated maxillary retrognathic patients who underwent different protraction methods were evaluated. Twenty patients treated with RME (Rapid Maxillary Expansion) made up the first group, and 20 patients treated with 5-week Alt-RAMEC (Alternate Rapid Maxillary Expansion and Constriction) protocol comprised the second group. Lastly, 19 patients on whom face masks with miniplates were applied were included in the skeletal anchorage (SA) group. Sixteen linear and four areal pharyngeal airway measurements were made on lateral cephalograms before and after treatment. Differences between the groups were assessed using analysis of variance (ANOVA) tests. The mean maxillary protraction levels were determined as 2.7, 3.69 and 4.01mm in the RME, Alt-RAMEC and SA groups, respectively. In the nasopharynx, AD1-PNS, AD2-PNS, PNS-Ba and PNS-Ho measurements revealed a significant increase in the SA group compared to the other groups (P<.05). In the oropharynx, PNS-Ep measurement increased significantly in the RME group (P<.05). In the total pharyngeal airway area, an increase was detected in the SA, Alt-RAMEC, and RME groups. The most effective protraction method in terms of pharyngeal airway dimensions, especially in the nasopharynx, is the application of the face mask with skeletal anchorage. A greater increase in vertical airway length (PNS-Ep) was observed with RME.

Computed Tomographic Evaluation of Three-dimensional Changes in Pharyngeal Airway in Class II Division 1 Patients treated with Twin Block Appliance:

Computed Tomographic Evaluation of Three-dimensional Changes in Pharyngeal Airway in Class II Division 1 Patients treated with Twin Block Appliance:

To compare volumetric dimensions of pharyngeal airway for different dentofacial skeletal patterns – Cone beam computed tomography

After a century of controversies, we are still not certain on the relationship between airway dimensions and facial morphology. Objective: The objective of the study was to measure nasopharyngeal airway dimensions and compare it among different skeletal patterns. Materials and Methods: Forty-five cone-beam computed tomography (CBCT) scans of patients between 16 and 25 years were used in the study. The nasopharyngeal airway was divided into upper, middle, and lower segments. CBCT images were grouped into skeletal Class I, Class II, and Class III. Results: There is no statistically significant difference between all the three groups for mean height of the upper, middle, and lower pharyngeal airways (P = 0.303, 0.479, and 0.077, respectively). There is no statistically significant difference between all the three groups for mean width of the upper, middle, and lower pharyngeal airways indicated by P = 0.643, 0.791, and 0.99, respectively. There is no statistically significant difference between all the three groups for mean breadth of the upper, middle, and lower pharyngeal airways (P = 0.939, 0.48, and 0.068, respectively). Furthermore, the mean total height of pharyngeal airway in Class I, Class II, and Class III groups indicates no statistically significant difference (P = 0.097). Conclusion: Nasopharyngeal airway dimensions seem to play no role in different skeletal patterns.

Volumetric and cephalometric evaluation of the upper airway of class III patients submitted to maxillary advancement

Abstract Introduction Anteroposterior maxillary deficiency can be associated with a decrease of upper airway volume. Maxillary advancement can improve the upper airway space. Aim To correlate cephalometric (2D) and volumetric (3D) measurements of the upper airway in class III patients treated by maxillary advancement. Material and method This retrospective transversal study was performed in ten adult patients submitted to maxillary advancement for correction of class III deformity secondary to maxillary anteroposterior deficiency. The Cone beam tomography files included in the medical records were used: (T1) pre-operative and (T2) 6 to 8 months postoperative. The DICOM files were imported and reconstructed for volumetric and cephalometric evaluation of the upper airway, as divided into nasopharynx, oropharynx and hypopharynx (Arnett &amp; Gunson FAB Surgery). Result Age ranged from 26 to 55 years with a mean of 36.3±9.2 years. There were no statistically significant differences for cephalometric and volumetric parameters of the three pharyngeal regions between T1 and T2 periods. This was due to the small amount of maxillary advancement necessary to correct the maxillary deformity in the studied patients (4.7±1.89mm). The correlation between area and volume was not statistically significant only for preoperative measurements of the nasopharynx (r=0.30, p=0.40). It was significant for the other regions and evaluation periods (p&lt;0.05). Conclusion Small maxillary advancements do not result in significant increases in airway dimensions.

An anthropometric and cephalometric study to correlate facial form to pharyngeal airway in Class I and Class II malocclusions

An anthropometric and cephalometric study to correlate facial form to pharyngeal airway in Class I and Class II malocclusions

An anthropometric and cephalometric study to correlate facial form to pharyngeal airway in Class I and Class II malocclusions

Introduction: The relationship between upper airways and changes in facial morphology has been extensively debated in the literature and remains controversial. Although many studies have been done regarding comparison of the nasopharyngeal space among patients with vertical and sagittal dysplasia, none so far has been carried out regarding relation between nasopharyngeal space and facial form. In view of the need to uncover new evidence to contribute to and assist in addressing this complex issue, this composite study was aimed to evaluate the variations in pharyngeal airway spaces in Class I and Class II malocclusions and their effect on facial form. Materials and Methods: The study was conducted on 180 subjects aged between 18 and 26 years. Subjects were divided into two groups; Class I and Class II malocclusions. Pharyngeal airway and facial forms were analyzed by cephalometrics and anthropometrics, respectively. Results: Results showed that McNamara's lower pharyngeal width is significantly less in Class II males than Class I males with statistically significant ( P = 0.009). Anthropometrically, nasal width (al r -al l ) is significantly less in Class II females than in Class I females ( P = 0.021). The lower aerial width and adenoid pharyngeal wall area had statistically significant difference between normo-, hypo-, and hyper-divergent growth patterns. Conclusion: It was concluded that sagittal mandibular development had significant effects on the dimensions of lower pharyngeal airway passage. Vertical dysplasia significantly affects the upper pharyngeal airway passage with a lesser value in vertical growth pattern than horizontal growth pattern. Facial form in vertical dysplasia showed a statistically significant difference between normal, horizontal, and vertical growth patterns. A significant correlation was found between variation in pharyngeal airway spaces to facial form in sagittal and vertical dysplasia.

Volumetric changes in pharyngeal airway in Class II division 1 patients treated with Forsus-fixed functional appliance: A three-dimensional cone-beam computed tomography study.

Objective:Recent years have witnessed a renewed interest to determine a quantifiable relationship between mandibular advancement performed with an orthodontic appliance and the resulting airway volume. The study was conducted to evaluate the volumetric changes in pharyngeal airway space using cone-beam computed tomography (CBCT) in Class II division 1 patients with retrognathic mandible treated by Forsus-fixed functional appliance and to compare them with their pretreatment findings.Materials and Methods:Thirty patients with Class II division 1 malocclusion of age group 10–17 years were selected randomly and evaluated for changes in pharyngeal airway volume with and without Forsus-fixed functional appliance. Patients in each group underwent CBCT scan of head and neck region at pretreatment stage and 6 months after the initial scan. Institutional approval for the project was obtained from the Ethical Committee. Volumetric changes of upper (oropharynx) and lower (hypopharynx) pharyngeal airways were measured on scanogram using computer software and intragroup comparisons were done.Results:There was a statistically significant increase in the volume of both hypopharynx and oropharynx and also total airway volume in patients treated with Forsus-fixed functional appliance. Three-dimensional reconstruction of the airway also demonstrates a considerable increase in pharyngeal airway space.Conclusion:Forsus-fixed functional appliance can be a promising appliance for improving pharyngeal airway volume in Class II division 1 patients with retrognathic mandible thus preventing obstructive sleep apnea and other respiratory problems in future. However, the long-term implications of this treatment modality need further consideration and a longer period of follow-up.

Evaluation of upper and lower pharyngeal airway in hypo and hyper divergent Class I, II and III malocclusions in a group of Egyptian patients

IntroductionSignificant relationships between the pharyngeal structures and both dento-facial and craniofacial structures have been reported. Hyper-divergent patients may lead to narrower antero-posterior dimensions of the airway. Some authors associated vertical growth pattern with obstruction of the upper and lower pharyngeal airways others associated mouth breathing and Class II malocclusion. So the aim of this study was to assess the upper and lower pharyngeal airway width in different antero-posterior and vertical growth patterns and to evaluate sexual dimorphism in a group of Egyptian patients. Patients and methodA sample of 300 Egyptian patients had divided into (5) groups (each group 60 patients) group 1 Class I, group 2 and 3 Class II division 1 (maxillary prognathism and mandibular deficiency), group 4 and 5 Class III (maxillary deficiency and mandibular prognathism). Each group was divided into three sub groups (hypo-hyper and normal divergent) vertical growth pattern. Each subgroup consists of 10 male and 10 female. The upper and lower pharyngeal airway widths were measured and compared for all groups. ResultsSignificant differences had exist regarding lower pharyngeal airway between Class I and class II division 1, Class I and Class III mandibular prognathism, Class II and Class III maxillary deficiency, Class II and Class III mandibular prognathism. Significant differences between hypo, hyper and normal vertical growth pattern. ConclusionsIn all groups hyper-divergent growth had narrower airway than normal and hypo-divergent growth. Class III had wider airway than Class I malocclusion. Class I had wider airway than Class II division 1 malocclusion. Lower pharyngeal airway in class II division 1 had the narrowest width in all groups. Lower pharyngeal airway in class III mandibular prognathism had the widest width in all groups. Males have wider pharyngeal airway than females.

Airway in Class I and Class II skeletal pattern: A computed tomography study.

Background and Objectives:A normal airway is required for the normal growth of the craniofacial structures. The present study was designed to evaluate and compare the airway in Class I and Class II skeletal pattern and to see if there is any association between the airway and maxillomandibular relationship.Materials and Methods:Peripheral nervous system computed tomography scans of 30 patients were divided into two groups as Class I (ANB ≤ 4.5°), Class II (ANB ≥ 4.5°). The Dolphin three-dimensional version 11 was used to assess the airway.Statistical Analysis:Correlations between the variables were tested with the Pearson correlation coefficient. Independent sample t-test was performed to compare the averages between the two groups. P < 0.05 was considered as statistically significant.Results:The ANB angle was negatively correlated with all the airway parameters. The airway area and volume was significantly reduced in Class II subjects compared to Class I.Conclusion:The results suggest a strong association between the airway and skeletal pattern showing a reduced airway in Class II patients with a high ANB angle.

Computed Tomographic Evaluation of Three-dimensional Changes in Pharyngeal Airway in Class II Division 1 Patients treated with Twin Block Appliance

Computed Tomographic Evaluation of Three-dimensional Changes in Pharyngeal Airway in Class II Division 1 Patients treated with Twin Block Appliance

Three Dimensional Study of Upper Airway in Different Antero-posterior Jaw Relationships through Cone Beam Computed Tomography

Introduction: This study aims at examining the difference of pharyngeal airways in patients with different occlusion postures, hoping to improve diagnostic methods and provide a stable treatment plan for orthodontic patients. Materials and Methods: The data were gathered through CBCT radiographies of patients from a specialized center for radiology. In each occlusion group according to the performed pilot study, 30 people (90 people in 3 groups of class I, II and III, male and female each) were chosen as the sample. The two-dimentional cephalometric radiographs were obtained from 3D-radiographs, and the patients’ malocclusion postures were determined according overjet and ANB angle, and finally grouped. Next, airway volume and dimensions were measured in cross sectional. Results: Statistical studies showed there is a significant relationship between anteroposterior positions of mandible and the volume of pharyngeal airway. Also, the volume of pharyngeal airway in class III patients is more than those of patients in class I. The volume of pharyngeal airway in class II patients is also less than those of class1 pa ents. Conclusion: Pharyngeal airway in class III is larger and in class II smaller. Therefore, considering this subject can lead to improving diagnostic ways, especially orthognatic surgery treatments, and providing a stable treatment plan for patients who need orthodentic treatment

Dimensional changes of maxillary sinuses and pharyngeal airway in Class III patients undergoing bimaxillary orthognathic surgery.

To evaluate the pharyngeal airway and maxillary sinus volume changes after mandibular setback surgery combined with maxillary advancement and/or impaction surgery. Seventeen Class III skeletal patients (11 females, 6 males) who required bimaxillary orthognathic surgery were selected. Volumetric measurements were performed using cone beam computed tomography (CBCT) scans preoperatively and 3.9 ± 0.87 months postoperatively. All the CBCT scans were assessed and analyzed using MIMICS 14.0 software. Preoperative and postoperative volumes of pharyngeal airway and maxillary sinuses and the relationship between the amounts of surgical movement of the jaws and the above volumes were statistically evaluated. The pharyngeal airway area presented no significant change except for the lower and total pharyngeal airway volumes in males, in whom a significant decrease was observed (4196.27 ± 2061.11 mm(3) and 3375.53 ± 3624.67 mm(3), respectively). No significant change was observed in the minimal cross-sectional area of the pharyngeal airway. There was a significant decrease in the volume of the maxillary sinuses after the surgery by 3448.09 ± 3315.56 mm(3). No correlation was found between the amount of skeletal movement and the change in the volume of pharyngeal airway or maxillary sinuses. There was a significant decrease only for lower and total pharyngeal airway volumes in males and a significant decrease in the volume of the maxillary sinuses.

Pharyngeal airway space, hyoid bone position and head posture after orthognathic surgery in Class III patients

To determine the effect of orthognathic surgery on pharyngeal airway in Class III patients and to (1) compare the results of different surgical techniques, (2) determine the change at the position of the hyoid bone, and (3) evaluate the craniocervical posture changes related to pharyngeal airway change. Forty-eight Class III adult patients were included in the study to assess airway space after orthognathic surgery. Nine patients were treated with maxillary advancement, seven patients were treated with mandibular set back, and 32 patients were treated with bimaxillary surgery. Cephalometric records were taken before treatment, after surgery, and about 1 year after surgery (at the end of the treatment). No differences were determined at the position of hyoid bone and craniocervical posture. Nasopharyngeal area was significantly increased in all groups (P < .05). Oropharyngeal area and SPSS and IPS parameters were significantly decreased after mandibular set back operation (P < .05). In bimaxillary and maxillary advancement groups, PPS parameter was significantly increased (P < .01), and IPS parameter was significantly decreased (P < .05). No differences were detected at oropharyngeal and hypopharyngeal areas in bimaxillary and maxillary advancement groups. Different surgical procedures have different effects on pharyngeal airway space.