VARIATION OF PALATINE THICKNESS DIMENSIONS MEASURED WITH CBCT IN POST INCISIVE FORAMEN IN ADOLESCENT PATIENTS

Abstract

BACKGROUND. Miniscrew is a temporary anchorage device (TAD) that ensures predictable tooth movement and prevents reciprocal movement. Since primary stability is related to the bone, vertical palatal bone thickness is the best indicator for placement site. AIM. The aim was to determine the sites with greatest bone thickness for orthodontic mini-screw insertion in the palate, characterized by sex and age. MATERIAL AND METHOD. 200 Cone Beam images were used in patients at the Imaging Unit of the Teaching Assistant Dental Clinic, Faculty of Dentistry, Universidad de La Frontera, Temuco, Chile, between 2011 and 2017. ICC 0.9 intra and interobserver variability was obtained. The images were grouped by sex and age range. Each image was evaluated in paracoronal sections at 4, 8, 16 and 24 mm posterior to the incisive foramen.  These were then evaluated on both sides at 3, 6 and 9 mm lateral to the mid palatal suture. RESULTS: For both sexes, the sites with the greatest bone thickness corresponded to the 4 mm paracoronal slice posterior to the incisive foramen, both right and left. There is no statistically significant difference between age ranges for all sites. CONCLUSIONS: The site with the highest probability of finding a favorable cortex is 4mm behind the incisive foramen and 9 mm from the median line of the maxilla. There are no differences according to sex; women have less bone thickness than men. When this information is considered in clinical work, an angulated and bicortical insertion may be indicated for unfavorable insertion sites.