Phenotypic Diversity in Patients with Moderate to Severe Class II Malocclusion and Its Relation to Upper Airway Space in Western Maharashtra Population

Abstract

newline Successful treatment of craniofacial anomalies and dental malocclusions is inherently dependent on an understanding and proper use of the soft tissue and muscle matrix which surrounds the craniofacial skeleton and dento-alveolar process. Stable treatment results depend upon establishing a balanced neuromuscular function of the craniofacial muscles which support the structures in their position. 1,2. The superior airway is an important anatomical surface in the human respiratory system. The structure and measurements of the upper airway are dictated by the anatomical structures such as the soft tissue, muscles and the craniofacial skeleton surrounding the pharynx. The different size of the pharynx affects the airway volume, facial growth pattern, risk of obstructive sleep apnea. Anatomical abnormalities of the soft tissue and craniofacial skeleton can change the airway volume3,4,5. The pathological, physiological and morphological obstructive processes such as hypertrophy of the adenoids and tonsils, allergic and chronic rhinitis, stimulatory environmental factors, congenital nasal deformities, trauma to the nose, polyps and tumors are among the predisposing factors for the superior airway obstruction5,6. In case of occurrence in the form of any obstruction leads to mouth breathing, which can change the anatomy of face and arch form, causing malocclusion7. Most previous studies in this respect had limitations since they evaluated the lateral cephalograms of patients. Lateral cephalometry provides a two-dimensional view of a three-dimensional (3D) structure and it will not asses the volume of structures8. Moreover, lateral cephalograms have other shortcomings such as distortion, low reproducibility due to problems in landmark identification, difference in magnification and superimposition of bilateral craniofacial structures8. Techniques enabling accurate detection of any correction in the superior airway thus consider the space and anatomical boundaries of the upper airway as the two main factors playing a role in normal growth and development of the craniofacial complex and correct treatment planning9. 1 Introduction Although computed tomography and cone beam computed tomography (CBCT) expose the patients to higher radiation dose compared to conventional digital radiography, CBCT is a highly acceptable imaging modality. CBCT has significantly lower patient radiation dose than computed tomography and has faster image acquisition10