Bone Regeneration Using PEVAV/β-Tricalcium Phosphate Composite Scaffolds in Standardized Calvarial Defects: Micro-Computed Tomographic Experiment in Rats

Abstract

Bone regeneration using beta-tricalcium phosphate (β-TCP) can be practiced using a biocomposite scaffold. Poly(ethylene-co-vinylalcohol)/poly(δ-valerolactone)/β-tricalcium phosphate (PEVAV/β-TCP) composite scaffolds showed promising in vitro results. This study evaluated the bone regenerative potential of PEVAV/β-TCP biocomposite scaffolds in standardized calvarial defects in a rat model over 4 and 10 weeks. Bilateral calvarial defects (5 mm in diameter and about 1.5 mm thick, equivalent to the thickness of the calvaria) were created in 40 male Wistar albino rats. The defects were grafted with either commercially available β-TCP (positive control), PEVAV/β-TCP 70, or PEVAV/β-TCP 50, or left empty (negative control), depending on the group to which the animal was randomly assigned, to be covered before flap closure with resorbable collagen membrane (RCM). At 4 and 10 weeks post-surgery, the collected rat calvaria were evaluated using micro computed tomography (micro-CT) analysis, to assess the newly formed bone volume (NFBV), newly formed bone mineral density (NFBMD), and remaining graft volume (RGV). The results showed that calvarial defects grafted with the PEVAV/β-TCP biocomposite exhibited higher NFBV than did control defects, both at 4 and 10 weeks post-surgery. Furthermore, calvarial defects grafted with PEVAV/β-TCP 70 showed the highest NFBV among all grafting conditions, with a statistically significant difference recorded at 10 weeks post-surgery. The PEVAV/β-TCP composite scaffold showed potentiality for the regeneration of critical-sized calvarial bone defects in a rat model.

Calvarial bone defect regeneration using beta-tricalcium phosphate: a translational research study in rat animal model

“…However, the fact that the use of beta-TCP led to near total defect fill, reiterates the advantage of grafting bone defect sites for early healing and functional rehabilitation. 1,9 Moreover, the choice of animal model for the present study was based on the versatility of the rat calvarial CSD, which is an easily approachable, reproducible, and orthotopic site for studying bone tissue engineering, and allows several modalities of analysis. 22 While the use of micro-CT has routinely been reported in the literature for studying bone regeneration, the present study used both micro-CT and histology to have a reliable comparison of the outcomes.…”

“…One of the greatest challenges faced by oral and maxillofacial surgeons is the reconstruction of craniofacial bone lost due to trauma, pathology and ablative surgery. 1 Some of the earliest methods for reconstruction of craniofacial bone defects included reconstruction plates, meshes and free non-vascularized bone grafts. This was followed by the use of vascularized free bone grafts and more recently tissue engineered options using bone substitute materials (BSM) along with adjuncts such as growth factors and stem cells.…”

“…In this context, micro computed tomography (micro-CT) based animal models for bone regeneration have become a crucial translational research tool, as they allow assessment of regenerated bone at varying time points from graft placement until healing, something not plausible in the actual clinical scenario. 1,9 Based on preexisting evidences available in the literature, the present study was envisaged with the intention of designing a critical sized calvarial defect model in rats for evaluating GBR using beta-TCP. 22 Moreover, this study also surmised that evaluating GBR at an early stage using not only histology, but also micro-CT assessment would provide insights about the remineralization potential of beta-TCP.…”

Bioactive Scaffolds as a Promising Alternative for Enhancing Critical-Size Bone Defect Regeneration in the Craniomaxillofacial Region

“…57 Other synthetic polymers tested to a lesser extent in vivo are the nonresorbable and cytocompatible material polystyrene (PS), 58 and poly(ethylene-co-vinyl alcohol)/poly(δ-valerolactone) (PEVAV). 59 Finally, other polymers such as poly-(ethylene oxide) (PEO), polydioxanone (PDS), nylon, poly-(vinylidene fluoride) (PVDF), polyurethane (PU), and polyacrylonitrile (PAN) present low use for craniofacial and dental bone repair. 60 3.4.…”

Long-Term Clinical Study of Implants Placed in Maxillary Sinus Floor Augmentation Using Beta-Tricalcium Phosphate

“…Among the various synthetic products used, one that has demonstrated proven efficacy in bone regeneration [17], alone or in combination, in both animals [18][19][20][21] and humans [22][23][24], is β-TCP. Beta-tricalcium phosphate (β-TCP) is a synthetic bone substitute with a rate of calcium and phosphate agents similar or close to cancellous bone [17].…”