Comparative in vitro study of commercially available products for alveolar ridge preservation

Ridge preservation is performed by placing a biocompatible product, following tooth extraction, to maintain bone volume. However, current ridge preservation therapies do not always maintain the volume required for future implant placement. Variations in surgical technique and material selection contribute to determining clinical outcomes. The wide variety of grafting materials available and conflicting efficacy reports make selecting the appropriate graft materials challenging. To investigate how different commercially available ridge preservation products might perform clinically: Helistat (collagen control) (Material 1), OsteoGen Plug (Material 2), Bio-Oss Collagen (Material 3), and J-Bone (native bone) (Material 4) were evaluated.

These products underwent field emission scanning electron microscopy, microcomputed tomography, helium pycnometry, and infrared spectra analysis. Human osteosarcomas were incubated on products and proliferation was monitored with CCK-8 and visualized with confocal microscopy. Scaffold osteoconductivity was evaluated through the cellular production of proteins osteocalcin, osteonectin, and osteopontin.

Results indicated that products varied in porosity and pore interconnectivity. Although Material 3 was chemically similar to Material 4, Material 2 demonstrated significantly better biocompatibility. Functionally, Material 1 and Material 2 elicited higher osteonectin release than Material 3 and Material 4 which suggests the latter products suppress endogenous osteonectin secretion. Furthermore, osteopontin secretion was minimal for all products, while osteocalcin was elevated. This seems to suggest that high levels of mineralization might be deleterious for bone regeneration.

Although all products are marketed as effective preservation products, the results demonstrated high variability in physical, chemical, and biological effects; however, this study suggests a product with higher ratio of collagen to mineral component may have the most desirable effects for the use in alveolar ridge preservation.