Relationship of oropharynx to craniofacial morphology in skeletal Class II patients (original) (raw)
Related papers
American Journal of Orthodontics and Dentofacial Orthopedics, 2013
The objective of this study was to characterize the volume and the morphology of the pharyngeal airway in adolescent subjects, relating them to their facial skeletal pattern. Methods: Fifty-four subjects who had cone-beam computed tomography were divided into 3 groups-skeletal Class I, Class II, and Class IIIaccording to their ANB angles. The volumes of the upper pharyngeal portion and nasopharynx, and the volume and morphology of the lower pharyngeal portion and its subdivisions (velopharynx, oropharynx, and hypopharynx) were assessed with software (version 11.5; Dolphin Imaging & Management Solutions, Chatsworth, Calif). The results were compared with the Kruskal-Wallis and the Dunn multiple comparison tests to identify intergroup differences. Correlations between variables assessed were tested by the Spearman correlation coefficient. Correlations between the logarithms of airway volumes and the ANB angle values were tested as continuous variables with linear regression, considering the sexes as subgroups. Results: The minimum areas in the Class II group (112.9 6 42.9, 126.9 6 45.9, and 142.1 6 83.5 mm 2) were significantly smaller than in Class III group (186.62 6 83.2, 234.5 6 104.9, and 231.1 6 111.4 mm 2) for the lower pharyngeal portion, the velopharynx, and the oropharynx, respectively, and significantly smaller than the Class I group for the velopharynx (201.8 6 94.7 mm 2). The Class II group had a statistically significant different morphology than did the Class I and Class III groups in the velopharynx. There was a tendency to decreased airway volume with increased ANB angle in the lower pharyngeal portion, velopharynx, and oropharynx. In the upper pharyngeal portion, nasopharynx, and hypopharynx, there seemed to be no association between the airway volume and the skeletal pattern. Conclusions: The Class II subjects had smaller minimum and mean areas (lower pharyngeal portion, velopharynx, and oropharynx) than did the Class III group and significantly less uniform velopharynx morphology than did the Class I and Class III groups. A negative correlation was observed between the ANB value and airway volume in the lower pharyngeal portion and the velopharynx (both sexes) and in the oropharynx (just in male subjects). (Am J Orthod Dentofacial Orthop 2013;143:799-809) T he upper airway is a structure responsible for one of the main vital functions in the human organism-breathing. The interest in studying the upper airway has always been present in orthodontics, and 1 main objective is to clarify the relationship between pharynx structures and craniofacial complex growth and development. 1-4 Obstructive processes of morphologic, physiologic, or pathologic nature, such as hypertrophy of adenoids and tonsils, chronic and allergic rhinitis, irritant environmental factors, infections, congenital nasal deformities, nasal traumas, polyps, and tumors, are predisposing factors to a blocked upper airway. When that happens, a functional imbalance results in an oral breathing pattern that can alter facial morphology and dental arch forms, generating a malocclusion. 2,5,6 Considering the functional matrix theory proposed by Moss, 7 the association of respiratory and masticatory functions and swallowing might act on craniofacial development.
PHARYNGEAL AIRWAY SPACE IN DIFFERENT SKELETAL MALOCCLUSION AND FACIAL FORMS
Background: Evaluation of the upper and lower airway space should be an integral part of diagnosis and treatment planning to achieve the functional balance and stability of the result after orthodontic or orthognathic treatment. This study aimed to analyze the pharyngeal airway space in different skeletal malocclusion and facial forms. Methods: Study was carried out in lateral cephalometric radiographs of 210 patients. Data was collected from March 2021 to December 2021. Pharyngeal airway spaces were analyzed according to McNamara Analysis. Upper and lower pharyngeal airway in different skeletal malocclusion and facial form was determined. Data was analyzed in SPSS version 20. Independent samples-t test was applied for gender distribution and Pearson correlation test was applied for upper and lower pharyngeal space. Results: The mean value of upper pharyngeal airway width in Class I, II and III were 12.07 mm, 11.57 mm and 12.34 mm respectively and for Mesofacial, Dolichofacial and Brachyfacial facial form were 12.35 mm, 11.83 mm and 11.81 mm respectively. Similarly, the mean value for lower pharyngeal airway width in Class I, II and III were 9.51 mm, 9.13 mm and 10.03 mm respectively and for Mesofacial, Dolichofacial and Brachyfacial facial form were 9.62 mm, 9.34 mm and 9.61mm respectively. Male had higher value of mean lower pharyngeal width than female. Conclusions: There was no impact of sagittal skeletal malocclusion on the upper and lower airways width. Also, there was no impact of different vertical skeletal types or facial forms on the upper and lower airways width.
Journal of Indian Orthodontic Society, 2015
Human beings are normally nasal breathers. The nasal and the oral cavities serve as pathways for respiratory airflow, however in some individuals due to nasal airway inadequacy or habit; the oral cavity becomes the predominant route for the respiratory airflow. [1] Changes in the dimensions of the respiratory tract that is, constriction can cause a decrease in airflow at times. [2] There are significant relationships between the pharyngeal dimensions and craniofacial abnormalities. [3] Literature supports the notion that mandibular deficiency is frequently associated with a narrower pharyngeal airway passage. [4] Using computed tomography (CT), Trenouth and Timms [5] found that the effects of rapid maxillary expansion (RME) on the nasal cavity are not uniform and the changes in the nasal dimensions are progressively less toward the back of the nasal cavity. Mean cross-sectional nasal cavity enlargements of between 1.4 and 4 mm for rapid expansion, 0.8 mm for a quad helix, and 0.5 mm for a removable appliance have been reported. [6,7] According to Saitoh, [8] the growth of the face (excluding the mandible) is completed at a relatively early age. Sixty percent of craniofacial development takes place during the first 4 years of life and 90% by age 12. Based on these observations, any intervention to open the airway must take place at an early
Pharyngeal airway parameters in subjects with Class I malocclusion with different growth patterns
Journal of Orthodontic Research, 2015
Objectives: (1) To test the null hypothesis that there are no signifi cant difference in the pharyngeal airway in subjects with Class I malocclusion with different growth patterns. (2) To test the null hypothesis that there are no signifi cant difference in dentofacial structure in subjects with Class I malocclusion with different growth patterns. Materials and Methods: Lateral cephalometric radiographs of 120 skeletally Class I were separated into three groups according to the SN-MP angle. Lateral cephalometric radiographs of 39 low angle, 45 high angle and 36 normal angle were examined. Group difference were analyzed with analysis of variance (ANOVA) and the Tukey test, at the P < 0.05 level. Results: For pharyngeal airway measurements statistically signifi cant difference were found in pharyngeal airway length, and D5 (retroepiglottal) pharyngeal width. No statistically signifi cant sagittal pharyngeal (D1-D5) parameters difference were determined between low angle and normal angle subjects. High angle subjects had lower sagittal pharyngeal D2 (retropalatal) and D5 (retroepiglottal) parameters than those with low and normal angle, additionally in high angle subjects had lower D1 (retropalatal) and D4 (retroglossal) parameters than those with normal angle subjects. According to ANOVA only 1 out of 9 dentofacial measurements showed not statistically signifi cant difference among different growth patterns. Conclusion: The null hypothesis was rejected. Signifi cant difference in pharyngeal airway measurements and dentofacial morphology of Class I subjects with different growth patterns were identifi ed.
IOSR Journals , 2019
Introduction: The upper and lower pharyngeal airways play an eminent role in the normal growth and development of craniofacial structures. The hyoid bone and its related musculature are also implicated in maintenance of the airway patency. Thus, present study is designed to compare the upper and lower pharyngeal airway dimension and hyoid bone position in subjects with normodivergent and hyperdivergent facial patterns in Class I and Class II malocclusions. Materials and Methods: The study was conducted on lateral cephalometric radiographs of 80 subjects. The subjects were divided into 4 groups, 20 subjects in each group, based on normodivergent and hyperdivergent facial patterns. Group 1: Skeletal Class I jaw relationship and normal growth pattern; Group 2: Skeletal Class I jaw relationship and vertical growth pattern, Group 3: Skeletal Class II jaw relationship and normal growth pattern, Group 4: Skeletal Class II jaw relationship and vertical growth pattern. The lateral cephalograms were taken in a natural head position. The upper and lower pharyngeal airway dimension was measured according to method described by McNamara and the hyoid position was measured according to Ashok Kumar Jena and RituDuggal. Results:A highly significant intergroup difference in the upper pharyngeal width was found between Groups 1 and 2, Groups 1 and 4, Groups 2 and 3, Groups 3 and 4. No significant intergroup differences were found for the lower pharyngeal airway. Anteroposterior position of the hyoid bone in subjects from skeletal Class I malocclusion was significantly forward as compared to the subjects from skeletal Class II malocclusion. Conclusion:The upper pharyngeal airway passage in subjects with vertical growth pattern is narrow as compared to the average growth pattern. Also, the position of hyoid bone is more posterior in Class II vertical grower as compare to Class I normal growers.
Craniofacial features of subjects with adenoid, tonsillar, or adenotonsillar hypertrophy
Progress in Orthodontics, 2011
Materials and methods: 20 patients with adenoid hypertrophy (AG), 20 subjects with tonsillar hypertrophy (TG) and 20 patients with adenotonsillar hypertrophy (ATG) were selected. A control group (CG) of 20 children with non-obstructive adenoids or tonsils was also obtained. Kruskal-Wallis test and Tukey's post hoc tests were used to compare the angular and linear measurements obtained from the lateral cephalograms. Results: No significant differences were observed between AG and CG. Conversely TG exhibited smaller ANB and OVJ values and a larger SNB value when compared to both CG and AG, larger Go-Me, Ar-Gn and Ar-Go measures and a smaller NSGn angle with respect to AG. ATG showed a smaller ANB angle in comparison with CG and AG, larger Ar-Gn and Go-Me values when compared to AG, a smaller SNB angle and a larger NSGn angle with respect to TG. Conclusions: Subjects with tonsillar hypertrophy showed an increased length of the mandibular ramus, a more horizontal growth direction, an increased length of the mandibular body, a more anterior mandibular position and a smaller sagittal discrepancy between the maxilla and the mandible than subjects with adenoid hypertrophy.
Introduction: The purpose of this study was to morphometrically investigate the growth pattern of the adenoids in growing subjects with hyperdivergent and hypodivergent vertical craniofacial features. Methods: In this retrospective study, we used a longitudinal sample of lateral cephalometric radiographs of 28 hyperdivergent and 30 hypodivergent subjects from 4 to 13 years of age. The radiographs were obtained from the American Association of Orthodontists Foundation Craniofacial Growth Legacy Collection. Measurements were made using digital tracings of the lateral cephalograms and point distribution models. Mixed-model analyses were used for statistical analysis. Results: The mean distance between the sphenoid bone and the posterior nasal spine increased up to 5.3 mm over a 9-year span (95% CI, 4.1-6.5 mm; P \0.001). Furthermore, the mean distance between the sphenoid bone and the posterior nasal spine differed significantly (P 5 0.029) between facial types; it was consistently greater (1.8 mm; 95% CI, 0.2-3.3 mm) in the hyperdivergent group. The nasopharyngeal airway area showed a trend to increase with age up to 12-fold (P \0.001). A significant interaction (P 5 0.004) was found between age and facial type. Assessment of the adenoid shapes showed greater convexities in the hyperdivergent group, which were observable from an earlier age and for a longer duration. Conclusions: Clear differences in the morphometric growth pattern of the adenoids were found between facial types. Evaluation of adenoid shapes showed more prominent convexities that lasted longer in the long facial types than in the short facial types. (Am J Orthod Dentofacial Orthop 2016;150:451-8)
Pharyngeal Airway and Craniocervical Angle among Different Skeletal Patterns
BioMed Research International, 2021
Purpose. The aim of the present study was to investigate the pharyngeal airway dimensions and their correlations among the craniocervical angle and skeletal patterns. Materials and Methods. Cephalometric radiographs were obtained from 300 patients (≥15 years of age), of whom 150 were male patients and 150 were female patients. The patients were divided into three groups according to their skeletal patterns. The following dimensions were measured: NP: nasopharyngeal airway; PS: shortest distance from the soft palate to the pharyngeal wall; MP: Me-Go line intersecting the pharyngeal airway; TS: shortest distance from posterior tongue to pharyngeal wall; LP: laryngopharyngeal airway; UE length: shortest distance from the uvula to the epiglottis; PW: width of soft palate; PL: length of soft palate; ANB angle; palatal angle; and craniocervical angle. Paired t -test, one-way analysis of variance (ANOVA), and Pearson correlation were applied for statistical analysis. The null hypothesis wa...
Journal of Health and Allied Sciences NU, 2017
An increase in oropharyngeal airway dimensions in growing patients with mandibular deficiency may have some major benefits in terms of craniofacial growth and function. If increases in these dimensions result in an increase in oropharyngeal airway capacity and there by better daytime and nocturnal respiratory function, the possible effect of an impaired oropharyngeal airway function as an etiological factor for abnormalities in facial structures might be reduced and might even modify the vertical and/or sagittal growth pattern of the craniofacial 3 complex. The mandibular advancement concept is widely used in dentofacial orthopedics to stimulate mandibular growth in skeletal Class II growing cases with mandibular deficiency. For prevention of collapse of the upper airway during sleep, oral 4 appliances are advised in adult obstructive sleep apnoea.