Role of intramarrow penetration in osseous repair: A pilot study in the rabbit calvaria

Background: The use of intramarrow penetration in combination with osseous reconstructive surgery has been recommended in various periodontal and oral surgical applications. The purpose of this pilot study was to evaluate the effect of intramarrow penetration on the rate of bone neogenesis in protected spaces created on the calvarial bone using occlusive titanium domes in 16 adult white rabbits. Methods: In each rabbit, 2 standardized circular 1 mm deep slits were prepared in the bone, one on each side of the midline using a trephine. Within the perimeter of one of the slits, the external cortical surface of the skull bone was mechanically perforated using a carbide round bur (experimental site), while the bone surface within the other slit (control site) was left intact. Subsequently, 2 prefabricated titanium domes with an inner diameter of 4.8 mm and an inner height of 3.0 mm were anchored in the prepared slits. The animals were divided into 4 groups of 4 rabbits each and were sacrificed at 10, 21, 42, and 60 days. The specimens were assessed for the percentage bone fill and density of the newly formed bone within the boundaries of the domes. Results: Histomorphometric analysis showed significantly increased bone neogenesis within the experimental domes at 10, 21, 42, and 60 days. A mean total area of 29% newly formed bone was demonstrated in the experimental sites at 21 days, while negligible bone formation (9%) occurred with the control domes at the same evaluation interval. Bone density was consistently higher in experimental domes at all healing intervals. Conclusions: Within the limits of this study, the results demonstrate that intramarrow penetration accelerates initial bone neogenesis and results in increased bone fill and density, suggesting that its use can be beneficial in bone regenerative procedures. J Periodontol 1999;70:1501-1510.