BACKGROUND: Some studies have advocated marrow penetration in guided bone augmentation (GBA), whereas others have shown that bone can be generated without marrow penetration. This study examined the effect of marrow penetration and the optimal rate of penetration. METHODS: In 10 rabbits, the calvarium was exposed, and circular grooves were prepared bilaterally. Within the circular groove, the external cortical surface of the skull was perforated mechanically using a number 4 round bur (experimental site), whereas the bone surface on the other groove (control site) was left intact. The rate of penetration was standardized as 28% for the experimental site and 0% for the control site. Subsequently, two standardized titanium caps with an inner diameter of 8 mm and an inner height of 4 mm were anchored in the prepared grooves. Five rabbits each were euthanized at 1 and 3 months, and the percent area of newly generated tissue and mineralized bone in the newly generated tissue under the titanium cap was determined. RESULTS: Histomorphometric analysis showed significantly increased bone neogenesis in the experimental site at 3 months. The percent area of mineralized bone in the newly generated tissue was consistently higher in the experimental site at 3 months. CONCLUSION: In the rabbit calvarium using a titanium cap GBA model, bone augmentation was significantly greater with marrow penetration than without penetration.
BACKGROUND: Some studies have advocated marrow penetration in guided bone augmentation (GBA), whereas others have shown that bone can be generated without marrow penetration. This study examined the effect of marrow penetration and the optimal rate of penetration. METHODS: In 10 rabbits, the calvarium was exposed, and circular grooves were prepared bilaterally. Within the circular groove, the external cortical surface of the skull was perforated mechanically using a number 4 round bur (experimental site), whereas the bone surface on the other groove (control site) was left intact. The rate of penetration was standardized as 28% for the experimental site and 0% for the control site. Subsequently, two standardized titanium caps with an inner diameter of 8 mm and an inner height of 4 mm were anchored in the prepared grooves. Five rabbits each were euthanized at 1 and 3 months, and the percent area of newly generated tissue and mineralized bone in the newly generated tissue under the titanium cap was determined. RESULTS: Histomorphometric analysis showed significantly increased bone neogenesis in the experimental site at 3 months. The percent area of mineralized bone in the newly generated tissue was consistently higher in the experimental site at 3 months. CONCLUSION: In the rabbit calvarium using a titanium cap GBA model, bone augmentation was significantly greater with marrow penetration than without penetration.