Palatal bone thickness compared with cone-beam computed tomography in adolescents and adults for mini-implant placement

Introduction: The purpose of this study was to compare the bone thickness of the palatal areas in early and late mixed and early permanent dentitions according to dental age. Methods: Cone-beam computed tomography scans of 118 subjects were selected and divided into 38 early mixed (8.03 +/- 0.93 years), 40 late mixed (11.51 +/- 0.92 years), and 40 permanent (20.92 +/- 1.17 years) dentition subjects. The measurements of palatal bone thickness were made at 49 sites by using InVivoDental5.0 software (Anatomage, San Jose, Calif). Repeated measures analysis of variance was used to analyze intragroup and intergroup differences as well as sex dimorphism. Results: There was significantly lower bone thickness in the early mixed dentition group than in the 2 other groups (P < 0.001). Bone thickness was higher in the anterior region than in the middle and posterior regions (P < 0.001). Also, significant differences were found among the midline, medial, and lateral areas of the palate. Conclusions: Palatal bone thicknesses were significantly lower in the early mixed dentition group than in both the late mixed and permanent dentition groups. These findings might be helpful for clinicians to enhance the successful use of temporary anchorage devices in the palate. (Am J Orthod Dentofacial Orthop 2012;142:207-12)