Experimental and morphological rationale for applying a synthetik bone graft containing hydroxyapatite and β-tricalcium phosphate in combination with a collagen sponge with polydeoxyribonucleotide in the treatment of mandibular bone defects

Abstract

Aim: To evaluate the effectiveness of the simultaneous use of a synthetic bone graft containing hydroxyapatite and β-tricalcium phosphate in combination with a collagen sponge impregnated with polydeoxyribonucleotide for the treatment of mandibular bone tissue defects through comprehensive morphological analysis of experimental material. Materials and Methods: In this study, an experiment was conducted on 96 male rats of the WAG population aged 6 to 8 months. All animals were randomly divided into four groups. Group 1 included 24 rats in which a perforated defect was modeled in the region of the mandibular angle. Group 2 included 24 rats in which a perforated defect similar to that in group 1 was modeled in the region of the mandibular angle. The defect was filled with the synthetic bone graft «Biomin GT» (RAPID, Ukraine), which is composed of hydroxyapatite and β-tricalcium phosphate. Group 3 included 24 rats with a mandibular defect similar to those in groups 1 and 2. The defect was filled with a collagen sponge (DSI Dental Solutions Ltd., Israel) impregnated with polydeoxyribonucleotide (BNC Korea, Korea). Group 4 included 24 rats with a mandibular defect similar to those in the previous groups. The defect was simultaneously filled with the synthetic bone graft «Biomin GT» (RAPID, Ukraine) and a collagen sponge impregnated with polydeoxyribonucleotide. In groups 1 to 4, six rats from each group were sacrificed on days 3, 7, 14, and 28. Fragments of the mandible from the area of the modeled defect were used as material for morphological analysis. Histological, morphometric and statistical research methods were used. Results: The authors’ comprehensive morphological analysis of experimental material demonstrated an activation of reparative osteogenesis in the mandible in cases where the perforated defect was filled either with the synthetic bone graft «Biomin GT», containing hydroxyapatite and β-tricalcium phosphate, or with a collagen sponge containing polydeoxyribonucleotide. The therapeutic effect was more pronounced in the group treated with the collagen sponge impregnated with polydeoxyribonucleotide. However, neither of these treatment strategies led to the formation of fully mature bone regenerate by day 28 of the experiment. In contrast, the simultaneous application of the synthetic bone graft «Biomin GT» and the collagen sponge with polydeoxyribonucleotide resulted in a more active stimulation of reparative osteogenesis and contributed to the formation of a structurally complete bone regenerate by day 28. Conclusions: Simultaneous filling of a bone defect in the mandible modeled in rats with the synthetic bone graft «Biomin GT», containing hydroxyapatite and β-tricalcium phosphate, and a collagen sponge with polydeoxyribonucleotide stimulates reparative osteogenesis and leads to the formation of a complete bone regenerate by day 28 of the experiment. The therapeutic effect is due to the rapid clearance of the defect cavity from blood fragments and alteratively changed tissues; active production and replacement within the regenerate of granulation, connective, and osteogenic fibroreticular tissues with the formation of lamellar bone tissue characterized by the presence of hematopoietic foci; decrease in the severity of inflammatory infiltration and hemodynamic disturbances in the tissues of the regenerate area.