Comparison of oropharyngeal airway dimensions in young adults with sagittal deficient maxilla and mandible

Abstract

Objective To compare oropharyngeal airway dimensions of young adults with sagittal deficient maxilla and mandible respectively, and to investigate the impact of sagittal maxillary and mandible deficiency on upper airway space. Methods 60 young adult orthodontic patients with average vertical angle were strictly matched according to gender, age, height, weight and mandibular plane angle, and they were divided into normal group, maxillary sagittal deficient group and mandibular sagittal deficient group according to the SNA and SNB angle (n=20 ). Seven linear measurements of oropharyngeal airway were obtained from their lateral cephalometric radiographs, and the volume and the minimum axial area of oropharyngeal airway, velopharyngeal airway and glossopharyngeal airway were obtained from their CBCT images through Dolphin software. Single factor variance analysis ( ANOVA ) was used to compare the differences of airway dimensions among three groups in SPSS19.0 software package. And the effect of sagittal development of jaws on upper airway was analyzed. Results There is no significant difference in all variables between normal group and maxillary sagittal deficient group (P>0.05), but most linear measurements, volumes (23 173.64±6 314.50 mm3 in normal group, 23 473.61±11 525.52 mm3 in maxillary sagittal deficient group, 15 956.26±6 548.98 mm3 in mandibular sagittal deficient group, P=0.008 ) and the minimum axial areas (367.04±107.77 mm2 in normal group, 402.94±183.34 mm2 in maxillary sagittal deficient group, 218.28±107.69 mm2 in mandibular sagittal deficient group, P=0.000 ) of oropharyngeal airway in sagittal deficient mandible group are significantly smaller than those in normal group and sagittal deficient maxillary group. Conclusions Oropharyngeal airway dimensions of young adults who have sagittally deficient mandible are significantly smaller than those of people who have normal bimaxillary development or sagittally deficient maxilla. But sagittally deficient maxilla has no significant impact on upper airway space. Key words: Oropharyngeal airway dimension; Maxillary and mandible; Sagittal; Lateral cephalometric radiograph; Cone beam computed tomography