Three-dimensional evaluation of upper airway in patients with different anteroposterior skeletal patterns.

To investigate variability in the upper airway of subjects with different anteroposterior skeletal patterns by evaluating the volume and the most constricted cross-sectional area of the pharyngeal airway and defining correlations between the different variables. The study sample consisted of 60 patients (29 boys, 31 girls) divided into three groups: Class I (1 ≤ ANB ≤ 3), Class II (ANB>3), and Class III (ANB<1), to evaluate how the jaw relationship affects the airway volume and the most constricted cross-sectional area (Min-CSA). Differences between groups were determined using the Tukey-Kramer test. Correlations between variables were tested using Pearson's correlation coefficient. The volume and the Min-CSA of the pharyngeal airway (PA) were significantly related to anteroposterior skeletal patterns (p < 0.05). The nasopharyngeal airway (NA) volume of Class I and Class III subjects was significantly larger than that of Class II subjects (p < 0.05). The Min-CSA and the length of PA were significantly related to the volume of PA (p < 0.05). The site and the size of the Min-CSA varied among the three groups. The volume and the most constricted cross-sectional area of the airway varied with different anteroposterior skeletal patterns. The NA volume of Class I and Class III subjects was significantly larger than that of patients with a Class II skeletal pattern.

Zheng ZH ，Yamaguchi T ，Kurihara A ，Li HF ，Maki K ... -  《-》

Pharyngeal airway characterization in adolescents related to facial skeletal pattern: a preliminary study.

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. Fifty-four subjects who had cone-beam computed tomography were divided into 3 groups-skeletal Class I, Class II, and Class III-according 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. The minimum areas in the Class II group (112.9 ± 42.9, 126.9 ± 45.9, and 142.1 ± 83.5 mm(2)) were significantly smaller than in Class III group (186.62 ± 83.2, 234.5 ± 104.9, and 231.1 ± 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 ± 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. 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).

Claudino LV ，Mattos CT ，Ruellas AC ，Sant' Anna EF ... -  《-》

Postsurgical volumetric airway changes in 2-jaw orthognathic surgery patients.

Findings from early cephalometric studies on airway changes after 2-jaw orthognathic surgery have been challenged because the previous anteroposterior interpretation of airway changes can now be evaluated in 3 dimensions. The aims of this study were to use cone-beam computed tomography to quantify the nasopharynx, oropharynx, and total airway volume changes associated with skeletal movements of the maxilla and mandible in a sample of patients undergoing 2-jaw orthognathic surgery for correction of skeletal malocclusion. Skeletal movements and airway volumes of 71 postpubertal patients (31 male, 40 female; mean age, 18.8 years) were measured. They were divided into 2 groups based on ANB angle, overjet, and occlusion (Class II: ANB, >2°; overjet, >1 mm; total, 35 subjects; and Class III: ANB, <1°; overjet, <1 mm; total, 36 subjects). Presurgical and postsurgical measurements were collected for horizontal, vertical, and transverse movements of the maxilla and the mandible, along with changes in the nasopharynx, oropharynx, and total airways. Associations between the directional movements of skeletal structures and the regional changes in airway volume were quantified. Changes in the most constricted area were also noted. Horizontal movements of D-point were significantly associated with increases in both total airway (403.6 ± 138.6 mm(3); P <0.01) and oropharynx (383.9 ± 127.9 mm(3); P <0.01) volumes. Vertical movements of the posterior nasal spine were significantly associated with decreases in total airway volume (-459.2 ± 219.9 mm(3); P = 0.04) and oropharynx volume (-639.7 ± 195.3 mm(3); P <0.01), increases in nasopharynx (187.2 ± 47.1 mm(3); P <0.01) volume, and decreases in the most constricted area (-10.63 ± 3.69 mm(2); P <0.01). In the Class III patients only, the vertical movement of D-point was significantly associated with decreases in both total airway (-724.0 ± 284.4 mm(3); P = 0.02) and oropharynx (-648.2 ± 270.4 mm(3); P = 0.02) volumes. A similar negative association was observed for the most constricted area for the vertical movement of D-point (-15.45 ± 4.91 mm(2); P <0.01). Optimal control of airway volume is through management of the mandible in the horizontal direction and the vertical movement of the posterior maxilla for all patients. The surgeon and the orthodontist should optimally plan these movements to control gains or losses in airway volume as a result of orthognathic surgery.

Hart PS ，McIntyre BP ，Kadioglu O ，Currier GF ，Sullivan SM ，Li J ，Shay C ... -  《-》

Three-dimensional analysis of pharyngeal airway volume in adults with anterior position of the mandible.

The purpose of this study was to examine whether the pharyngeal airway volume in adults with skeletal Class III malocclusion is greater than in subjects with Class I occlusion and whether the pharyngeal airway volume correlated with facial morphology. Cone-beam computed tomography scans were obtained from 60 subjects, who were assigned to 2 groups. The skeletal Class III malocclusion group consisted of 31 subjects (16 men, 15 women) who had planned on orthodontic treatment with orthognathic surgery. The Class I malocclusion group consisted of 29 subjects (14 men, 15 women). The pharyngeal airway volumes and areas were measured and compared with cephalometric variables. The cross-sectional areas of the lower part of the pharyngeal airway and the volume of the upper part of the pharyngeal airway were greater in skeletal Class III malocclusion patients than in Class I malocclusion patients. The volume of the upper part of the pharyngeal airway showed negative correlations with ANB angle and the Wits appraisal, and positive correlations with SNB, APDI, pogonion to N-perp, gonial angle, and FMA. The volume of the upper part of the pharyngeal space was greater in patients with skeletal Class III malocclusion, and the increased volume of the upper part of the pharyngeal airway showed significant correlations with measurements characterizing the anterior position of mandible.

Hong JS ，Oh KM ，Kim BR ，Kim YJ ，Park YH ... -  《-》

Retrospective analysis of the upper airway anatomy and Sella turcica morphology across different skeletal malocclusions: a computerized technique.

Marya A ，Inglam S ，Dagnaud A ，Wanchat S ，Naronglerdrit P ，Rithvitou H ，Chantarapanich N ... -  《BMC Oral Health》