Comparison of Bovine and Porcine Collagen Membranes for Potential Applications in Guided Bone Regeneration: An In Vivo Pre-Clinical Evaluation

In an effort to improve bone response, predictably regenerate lost tissue, and provide an anatomically pleasing ridge contour for biomechanically favorable and prosthetically driven implant placement, guided bone regeneration (GBR) procedures have been indicated. This study provides the first direct in vivo comparison of the biocompatibility of an experimental porcine-derived collagen membrane (CMI, Regenity Biosciences, Paramus, NJ, USA) and a commercially available bovine-derived collagen membrane (CopiOs, ZimVie, Palm Beach Gardens, FL, USA) in a beagle mandibular model for the purposes of GBR. Four bilateral defects of 10 mm × 10 mm through the mandibular thickness were placed in each of n = 16 adult beagle dogs. Defects were filled with a deproteinized porcine-derived particulate graft and were covered either with CMI or CopiOs to allow compartmentalized healing. Animals were euthanized after 4, 8, 12, or 16 weeks post-operatively (n = 4 beagles/time point). Bone regenerative capacity, graft, and soft tissue presence were evaluated by histomorphometric and microtomographic analyses. Outcome variables were compared using a mixed model analysis with fixed factor variables of time and material. Qualitatively, no histomorphological differences in healing were observed between the membrane groups at any time point. Histomorphometrically, CMI and CopiOs presented statistically significant differences in bone (mean ± SD: 38.27% ± 15.20 vs. 17.43% ± 15.49, respectively, p = 0.016) and soft tissue presence (mean ± SD: 50.88% ± 11.83 vs. 68.21% ± 16.98, respectively, p = 0.026) at 8 weeks. These results might influence treatment timing in clinical practice, by enabling early implant placement or shorter healing intervals. No significant differences were detected in these parameters at any other healing time point (p > 0.05). CMI and CopiOs showed no signs of adverse immune response and led to similar trends in bone regeneration after 16 weeks of permitted healing. Both membranes minimized soft tissue infiltration and maintained defect stability over the observed healing periods without adverse events such as inflammation and/or foreign body reaction.