The correction of asymmetry using computer planned distraction osteogenesis versus conventional planned extra-oral distraction osteogenesis: A randomized control clinical trial

The aim of the current study was to evaluate the effect of the use of computer-guided surgical templates in association with mandibular distraction osteogenesis to correct mandibular asymmetry. In the study group a simulation process was conducted to restore the exact position of the chin skeletally by planning the osteotomy orientation, distractor vector, pin positions, and distraction distance calculation. The Control group was treated with conventional distraction in which an oblique osteotomy was done, and distraction was performed until the midline coincided. Patients were randomly allocated into two groups, study and control. The study included (12) young patients; ten males participated and two females (average age 14 +/- 6 years) (Range = 6-23 years)). There was a statistically significant (P = 0.02) improvement in smile orientation in the study with 63.7% +/- 19% improvement compared to control, which had only 37% +/- 14%. There was a statistically significant (P = 0.02) improvement in ramus height in the study with 93% +/- 9% improvement compared to control, which had only 74% +/- 16%. There was a non-significant (P = 0.2) improvement in chin deviation in the study with 42% +/- 26% improvement compared to control, which had only 25% +/- 15%. The secondary outcome results showed that there was statistically significant (P = 0.0001) improvement in smile orientation post distraction 50% +/- 21%, there was statistically significant (P= P=0.002) improvement of ramus height post distraction osteogenesis 82% +/- 16%, and there was statistically significant (P = 0.0001) improvement in chin deviation 33% +/- 22% post distraction osteogenesis. Overall, the current research recommends the use of computer planned distraction instead of conventional planned distraction in order to achieve better symmetry. Distraction failed in correction of chin asymmetry; thus, the authors recommend performing genioplasty post distraction after the patient reaches puberty for more optimum results regarding the chin. (C) 2022 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.