July 2016

Objectives: This study was designed to compare skeletal and dental angular measurements of orthodontic treatment facilitated by cone beam guided corticotomy to that of conventional orthodontic treatment as well as treatment time. Methods: Twenty female and male adult orthodontic patients with an age range of 19 to 29 years and suffering from bimaxillary protrusion recommended for first premolars extraction were randomly assigned to one of two groups: The test group was treated with a closed technique of corticotomy -facilitated orthodontics using a piezoelectric device and guided by cone beam radiography. The control group was treated with conventional orthodontic treatment. A fi xed orthodontic appliance was used and anchorage was done using miniscrews. Cone beam computed tomography (CBCT) was performed for each patient of the test group. Image analysis was done using On Demand Software where linear and angular measurements were taken to virtually assess the configuration of the six anterior teeth together with the position of the lingual and mental foramen. These measurements were transferred to the study model and a surgical guide was constructed. Corticotomy was performed using the piezotome with the aid of the constructed guide. Orthodontic measurements were recorded pre- and post-treatment including total treatment time for both groups. Results: Using a surgical guide, the surgery was a straightforward procedure. At the end of treatment, by comparing the mean change of skeletal angular measurements between the two groups, the control group showed a signifi cant decrease in the mean of change in the facial angle compared to the test group (p ≤ 0.05). By comparing the mean change of dental angular measurements between the two groups, the test group showed a significant decrease in SN – U1° (angle between the sella-nasion line and the maxillary incisor), and a signifi cant increase in the interincisal angle compared to the control group (p ≤ 0.05). Regarding the total treatment time, the test group showed a significant decrease in the mean total treatment time compared to the control group. Conclusion: CBCT provided comprehensive information regarding anatomical relationships and individual patient findings for improved diagnosis and treatment planning. The use of a surgical template guided by the cone beam imaging provided a novel conservative technique that simplified the surgical procedure. Corticotomy-facilitated orthodontics showed marked improvement in some skeletal and dental angular measurements compared to conventional orthodontics in patients with bimaxillary protrusion, as well as a decrease in treatment time.