Research Information System
Thesis Type: Expertise In Medicine
Institution Of The Thesis: Gazi Üniversitesi, Tıp Fakültesi, Turkey
Approval Date: 2016
Student: İSMAİL DALDAL
Supervisor: ALPASLAN ŞENKÖYLÜ
Abstract:Introduction: Bone grafting is essential in posterolateral spinal fusion surgery. Although autogenous grafts have ideal graft properties, their use is limited due to the donor site comorbidities. For this reason, a variety of graft materials have been researched. The use of carbon nanotubes (CNTs) with ceramics such as hydroxyapatite (HA) has recently been used and has led to positive effects in bone tissue engineering. In this study, the effects of CNT-assisted HA-tricalcium phosphate (TCP) material on spinal fusion, which were not previously used as graft material in spinal fusion, have been investigated. Material and methods: We operated 20 Sprague-Dawley rats to create a posterolateral fusion model between the lumbar 4-5 (L4-L5) vertebrae. Subjects were divided into four groups of five. The L4-L5 posterior arches of all the subjects were decorticated. No graft material was applied to the first group (Group 1). In the second group, we used only CNTs (Group 2),in the third group HA-TCP synthetic ceramics (Group 3) and the fourth group CNT / HA-TCP composite (Group 4). After eight weeks, all subjects were sacrificed and the obtained lomber fusion segments were assessed by manual palpation, radiological images, biomechanical tests (2 'sham animals from each group), histological evaluation and micro computerized tomography (micro-CT) device. Findings: There was no fusion in the Group 1 where only decortication was done. In Group 2 (CNTs), there was no solid fusion, although there was a significant difference (p <0.01) between manual palpation, histological and micro-CT scans according to Group 1. In Group 3 (HA-TCP) and Group 4 (CNT/HA-TCP), 60% and 100% fusion was detected with manual palpation, respectively. Radiologically, fusion rates were 60% and 92%, histologically 42% and 68.5%, respectively. Micro-CT scans revealed ossification rates (bone volume / fusion mass) of 18.7% and 33.1%, respectively. Significant differences were found between groups 3 and 4 in all the evaluations (p <0,01). Conclusion: Although CNTs are incapable to form spinal fusion when used alone; they significantly increase fusion rates, especially with ceramic-based synthetic grafts, due to their high biocompatibility and unique biomechanical properties compatible with bone tissue.