A Cephalometric Study Of Upper Airway In Permanent Dentition In Skeletal Class â…¢ Malocclusion

Objective:①To investigate upper airway form and its potential association with Craniomaxillofacial in permanent dentition in skeletal class Ⅲ malocclusion. ②To study age-related and sex-related effect on upper airway in permanent dentition in skeletal class Ⅲ subjectsMethods:80 patients among 12-18 years old of skeletal class Ⅲ malocclusion were included.80 patients among 12-18 years old of skeletal class I malocclusion were selected as the control group.Lateral cephalometric radiographs before treatment of both groups were used to measure the Craniomaxillofacial and upper airway values. The data were analyzed using Independent sample t-test and Pearson correlation analysis.Independent sample t-test was assessed to compare variance between each group according to age and gender difference.Results:1.Compared with the class I malocclusion adolescents, Class Ⅲ malocclusion adolescents’ nasopharyngeal airways were narrower but hypopharynx and laryngopharynx were larger (P<0.05),except for male between 11-15 years old.2.UPW-PNS are positively correlated with SNA angle and Ptm-A length (P<0.05); palatopharyngeal airways are positively correlated with SNA angle、Ptm-A length、SNB angle and Go-Gn length (P< 0.05).Laryngopharynx are positively correlated with SNB angle、Go-Gn length (P<0.05).3. Female have larger SPP-SPPW and TB-TPPW than male in 11-15 years old (P<0.05).Male have larger TB-TPPW and V-LPW than female in 15-18 years old(P< 0.05).4.PNS-R、U-MPW、laryngopharynx and hypopharynx in male patients with skeletal Class III malocclusion were highly correlated with age (P< 0.05). Sagittal upper airway values in female with Class Ⅲ malocclusion showed nonsignificant correlation with age(P>0.05)Conclusion:Compared with the class I malocclusion adolescents, Class III malocclusion patient’s nasopharyngeal airways were narrower but hypopharynx and laryngopharynx were larger.Female have larger hypopharynx and palatopharynx than male in 11-15 years old. Male have larger hypopharynx and laryngopharynx than female in 15-18 years old. PNS-R,UMPW, hypopharynx and laryngopharynx grow with age in male patients.Age have no significant correlation with other variances.