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Introduction: Distraction osteogenesis is an integral part in management of mandibular defects associated with hemifacial microsomia and post-ankylotic mandibular defects. The most difficult part in distraction osteogenesis is the prediction of distraction vector and risk of injury to vital structures as inferior alveolar. The present study aimed to present 3-dimensionally constructed computer-guided splints in distraction osteogenesis to get an ideal vector and minimal risk of vital structures injury. Material and Methods: The technical note presents cases series of 6 patients who had computer-guided distraction osteogenesis surgery using prefabricated splints. Results: The distance between the virtual and physical pins and osteotomy was measured, and the deviation of the vector angle and osteotomy angle was also assessed. Average deviation in pin distance was 3 mm and in vector angle 13.5°. Average deviation in osteotomy distance was 2.6 mm and in osteotomy angle 14.4°. None of the cases had injury to vital structure. There was significant improvement (P = 0.0078) in the medial canthus–buccal commissure distance where the arithmetic mean improved from 59.6 (SD = 10.1) mm pre-distraction in the defective side to 67.1 (SD = 8) mm post-distraction. The degree of correction was 97% compared to the normal side. Conclusion: 3D printed surgical stents were successful in transferring the virtual treatment plan of mandibular distraction osteogenesis into the surgical theatre with an acceptable margin of error and without injury to any vital structures

Distraction osteogenesis (DO) bone regenerate usually suffers from an inferior quality especially with rapid rate. This study was conducted to investigate the effect of mesenchymal stem cells (MSCs) application on different rates of distraction bone quality. Twenty-four goats were divided into group A with standard DO and group B with rapid distraction osteogenesis (RDO) both aided by MSCs. Group C with standard DO and group (D) with RDO were controls. Kruskal-Wallis test and Conover's post hoc analysis was used to evaluate significance ( = 0.05). Histomorphometry showed a strongly significant (SS) increase ( = 0.00036) in trabecular bone (TB) in group A (TB = 174.7 µm, SD = 33.5) and group B (TB = 166.8 µm, SD = 14) compared with group C (TB = 115.4 µm, SD = 19.6) and group D (TB = 86.1 µm, SD = 9.3). There was SS decrease ( = 0.00093) in osteoid percentage (OP) in group A (OP = 13.4%, SD = 2) and group B (OP = 11.5%, SD = 6.5) compared with group C (OP = 27.3, SD = 3.5) and group D (OP = 26.2%, SD = 2.6). Energy dispersive X-ray showed a nonsignificant increase ( = 0.11) in calcification (Ca %) in group A (Ca % = 17.6%, SD = 4.9) and group B (Ca % = 17.6%, SD = 4.3) compared with group C (Ca % = 14.2%, SD = 6.7) and group D (Ca % = 11.5%, SD = 2.4). MSCs application improved microscopic bone quality during standard DO and RDO. However, macroscopic bone quality improvement still needs further investigation.

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Background: This study was conducted to assess effect of bone marrow aspirate concentrate (BMAC) on enhancing biomechanical properties of distraction osteogenesis (DO). Methods: Twelve rami of goats had distraction and were divided into test group (DO bone supplemented with BMAC) and control group. Results: Assessment of bone-width showed nonsignificant (P = 0.9) increase in test group (mean = 5.3 mm, standard deviation = 1.9 mm) compared to control group (mean = 5.2 mm, standard deviation = 0.8 mm). Assessment of radiographic density showed nonsignificant (P = 0.5) increase in test group (mean = 163.4 Hounsfield Unit, standard deviation = 6.5 Hounsfield Unit) compared to control group (mean = 156.6 Hounsfield Unit, standard deviation = 21.8 Hounsfield Unit). Histomorphometry of mature-bone % showed significant (P = 0.02) increase in test group (mean = 30%, standard deviation = 9.8%) compared to control group (mean = 15.9%, standard deviation = 7.2%). Assessment of biomechanical testing (bone strength) by 3-point bending test showed nonsignificant (P = 0.7) increase in test group (mean = 511.6 Newton, standard deviation = 189.1 Newton) compared to control group (mean = 467.8 Newton, standard deviation = 201.1 Newton). Conclusion: The BMAC failed to improve both bone quantity and biomechanical bone strength of distracted bone.