Architecture and Microstructure of Cortical Bone in Reconstructed Canine Mandibles After Bone Transport Distraction Osteogenesis

Abstract

Purpose Reconstruction of the canine mandible using bone transport distraction osteogenesis has been shown to be a suitable method for correcting segmental bone defects produced by cancer, gunshots, and trauma. Although the mechanical quality of the new regenerate cortical bone seems to be related to the mineralization process, several questions regarding the micro-structural patterns of the new bony tissue remain unanswered. The purpose of this study was to quantify any microstructural differences that may exist between the regenerate and control cortical bone. Methods Five adult American foxhound dogs underwent unilateral bone transport distraction of the mandible to repair 30–35 mm bone defects. Animals were sacrificed 12 weeks after the beginning of the consolidation period. Fourteen cylindrical cortical samples were extracted from the superior, medial, and inferior aspects of the lingual and buccal plates of the reconstructed aspect of the mandible and 21 specimens were collected similarly from the contralateral aspect of the mandible. The specimens were evaluated using histomorphometric and micro-computed tomography techniques to compare their microstructure. Results Except for differences in Haversian canal area, histomorphometric analyses suggested no statistical differences in microstructure between regenerate and control cortical bone. Morphological evaluation suggested a consistent level of anisotropy possibly related to the distraction vector. Conclusions After 12 weeks consolidation, bone created during bone transport distraction osteogenesis is comparable to native bone in microstructure, architecture, and mechanical properties. It is proposed that after enough time, the properties of the regenerate bone will be identical to that of native bone.

Transport Distraction Osteogenesis for Maxillomandibular Reconstruction: Current Concepts and Applications

“…In a study conducted at Mercer university (USA) on the architecture and microstructure of cortical bone regenerated with TDO, it was found and concluded through their study that at 12 weeks of consolidation, bone created during bone TDO was comparable to native bone in microstructure, architecture, and mechanical properties and when appropriate time has lapsed, the properties of the regenerate bone were identical to the host bone [16].…”

Biomechanics of the Canine Mandible During Bone Transport Distraction Osteogenesis

“…This surgical process has been widely used not only because it has been shown that the quality of the new cortical bone created during the BTDO procedure resembles the original bone [26,31,32], but also because it allows early implants placement induced by the functional recovery of the mandible [33,34]. The present article provides evidence for a couple of biomechanical benefits of the mandibular BTDO process.…”

Critical Sized Mandibular Defect Regeneration in Preclinical In Vivo Models

“…The articles which evaluated transport-disc-distraction osteogenesis used either internal or external distractors to attempt to bridge critical sized defects [17,18,21,49,50]. Authors carrying out TDDO on defects greater than 30 mm reported non-union rates between subjects at 50-100 % due to inadequate contact of the transport disc with the docking site [20,21].…”