ALVEOLAR BONE REPLACEMENT WITH NON-INDUCING BIOMATERIALS BASED ON THE INTRAMEMBRANOUS OSSIFICATION PATTERN: histomorphological study

Rationale. The lack of knowledge about the nature of intramembranous ossification pattern during the replacement of the alveolar bone defects, in contrast to the more studied process of enchondral ossification, explains the contradictory interpretations of treatment outcomes and assessments of the effectiveness of reconstructive techniques in dentistry and maxillofacial surgery.

The aim of the experiment was to study the early replacement of extensive defects of the alveolar bone in the context of intramembranous ossification pattern using non-inducing biomaterials.

Materials and methods. The KubSMU’s Research Laboratory was used to conduct an experiment involving on three sexually mature & healthy minipigs. Acellular dermal matrix and granules of natural osteoconductive biomaterial were introduced into the extensive alveolar bone defects. On the 120th day, mandibular bones were isolated for histolomorphological analysis. Hematoxylin and eosin, Van Gieson’s picrofuxin and Masson’s trichrome staining were used. The randomization method was not applied.

The results and discussion. Replacement of defects of the extensive alveolar bone defects occurs due to vascularization de novo by triggering the process of local hematopoiesis. In the venous link of the regional vascular bed, sinusoidal capillaries with hematopoietic cells maturing inside are formed, some of which migrate into the surrounding tissue through discontinuous walls. Immature progenitor cells actively proliferate and differentiate, mainly, into segmented granulocytes, which participate in dynamic processes of intercellular and cell-matrix interactions with the formation of transitional intermediate cellular forms. As a result, reticular connective tissue is formed – a niche of bone marrow structures, osteoid is produced with the appearance of reticulofibrous bone beams. The effect of non-inducing matrix and granular biomaterials on vasculogenesis was analized.

Conclusion. The results of the experimental study reveal the existence of a direct relationship between the initiation of hematopoiesis in the sinusoidal capillaries of the alveolar defect zone and the events of intramedullary osteohistogenesis. The active and universal role of granulocytes in the normal healing and asynergy of bone growth was revealed in the presence of residual granules of osteoconductive biomaterials.