Two-dimensional Analysis of Oro-pharyngeal Airway Space Area in Patients with Bimaxillary Protrusion

Abstract

Background: Bimaxillary protrusion or full mouth appearance is a dento-alveolar condition associated with proclination of upper and lower incisors with resultant aesthetic challenges. From literature reports, it has been suggested that posture of the oropharyngeal organs may have great influence on the positioning of dento-alveolar structures and vice-versa. Due to the physiological importance of oro-pharyngeal space, it is necessary therefore, to evaluate their relationship with dento-alveolar structures. The purpose of this study was to determine the relationship between oropharyngeal space and dento-alveolar position of incisors in patients with bimaxillary proclination and normal incisal relationship.
Method: Cephalometric radiographs were obtained from 100 orthodontic patients who were grouped into bimaxillary proclination (study group) and normal interincisal relationship as control group. Patients were equally assigned to either of the groups based on their interincisal angle. Radiographs were taken under a standardized condition, traced and analysed. The bimaxillary proclination and normal interincisal groups were defined as patients with interincisal angle of less than 1080 and interincisal angle equal to or greater than 1080 respectively. Oropharyngeal airway space area was also determined. Analysis of data was done using SPSS version 11 and computer programme for epidemiological analysis.
Results: The mean values of soft palate and oropharyngeal parameters were higher in subjects with normal interincisal relationship with the exception of soft palatal length and soft palatal thickness. However, all these differences were not statistically significant (P>0.05). Multiple regressions showed that none of the variables (palatal airway, lingual airway and pharyngeal space area) can act as a predictor for interincisal relationship.
Conclusion: The study concluded that there was no significant difference in oro-pharyngeal airway dimensions between bimaxillary proclination and normal interincisal relationship subjects. Keyword: oro-pharyngeal, Airway Space, Bimaxillary Protrusion, Cephalometric