Abstract

Objective: To evaluate the anatomical variations in bicortical thickness of the mid palatine region in order to calibrate the maximum depth of micro osteoperforation permissible at various sites along the midpalate.
Design: This was a retrospective cone-beam computed tomography study
Setting: The study was conducted in Department of Orthodontics and Dentofacial Orthopedics
Methods: CBCT images of 60 subjects between the age of 14-28 years were taken up for evaluation from the records of the dental hospital. The sixty scans were from 37 males and 23 females. The CBCT images of subjects were evaluated by two investigators to assess the bicortical thickness of bone in the midpalatal region using fixed reference points and planes. Mean and standard deviation of bicortical thickness at various fixed landmarks were calculated. One-way ANOVA was done to check for variation of bicortical thickness among various sites in males and females. Intra operator reliability was checked by the paired T- test and Kappa statistics were used to evaluate inter-operator reliability between the observations by two observers (A.M, H.B).
Results: A mean value of 8.93+/-1.67mm, 6.37+/-1.56mm, 4.42+/-1.40mm, 3.11+/-1.21mm, 2.47+/-0.95mm, 2.07+/-0.93mm was obtained for reference points A, B, C, D, E and F respectively in males. It was observed that a mean value of 7.93+/-1.56mm, 5.48+/-1.39mm, 3.66+/-1.01mm, 2.81+/-1.06mm, 2.35+/-1.08mm, 2.09+/-1.18 mm was obtained for points A, B, C, D, Eand Frespectively in females. Statistically significant difference was observed between the six points (ANOVA test; p value- 0.00). The Intra operator reliability was assessed using a paired T-test and was estimated to be 0.93 and the inter-operator reliability by Kappa statistics was 0.321.
Conclusion: The bicortical thickness of the mid palate varies showing more thickness anteriorly and progressively getting thinner posteriorly. The anterior segment showed more variations in the thickness compared to the posteriors. Micro osteoperforation of palate can be done upto a depth of 8.93 mm in males and 7.93mm in females and a minimum depth of 3.11 mm in males and 3.66mm in females is possible in the anterior half of the palate.