Dentoalveolar heights in skeletal class I normodivergent facial patterns.

OBJECTIVE To determine the dentoalveolar heights (mm) in skeletal class I normodivergent facial pattern and compare the same heights in male and female subjects. STUDY DESIGN Cross-sectional observational study. PLACE AND DURATION OF STUDY Orthodontics Clinic, The Aga Khan University Hospital, Karachi, from July to October 2009. METHODOLOGY Eighty one subjects were selected from the orthodontic record at the Aga Khan University Hospital Karachi. The inclusion criteria were an age range of 12 to 30 years and skeletal class I normodivergent facial pattern with exclusion criteria of prior orthodontic treatment, restored teeth and craniofacial anomalies/syndromes. The pre-treatment cephalographs of the patients were traced manually on acetate paper by the principal investigator. The various land marks were marked and the parameters were recorded. Mean and standard deviations were determined. Independent sample t-test was used to find gender dimorphism. RESULTS The mean age of the sample was 15.8 ± 3.4 years. Mean ANB angle for the entire sample was 2.6° ± 1.2° and for angle SN-MP was 31.5° ± 2.5°. Descriptive analysis presented mean value of upper anterior, upper posterior, lower anterior and lower posterior dentoalveolar heights to be 28.5 ± 2.7 mm, 22.9 ± 2.6 mm, 41.3 ± 2.9 mm and 31.5 ± 3.2 mm respectively. Male subjects had significantly greater mean values for lower anterior and posterior dentoalveolar heights (p=0.02 and 0.05 respectively). CONCLUSION The mean dentoalveolar heights for the skeletal class I normodivergent sample were established. No gender dimorphism was found for upper dentoalveolar heights however, lower anterior and lower posterior were significantly greater in males as compared to females. All the values of dentoalveolar heights for male subjects were greater than female subjects.