Microvessel density and vascular endothelial growth factor expression in sinus augmentation using Bio-Oss

The aim of this study was to evaluate microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in sinus augmentation with Bio-Oss.

Twenty patients participated in this study. The sinuses were filled with 100% Bio-Oss. Implants were inserted after 3 months in group A, and 6 months in group B. A trephine was used to harvest bone cores. As control, the pre-existing subantral bone was used.

The mean MVD in control bone was 23.6 +/- 1.8. In the sites augmented with Bio-Oss, at 3 months, the MVD was 23.3 +/- 2.1, while in the sites retrieved at 6 months the MVD was 29.5 +/- 2.4. The difference in MVD between the control bone and group A was not statistically significant. The difference between the control bone and group B was statistically significant (P < 0.05). The statistical analysis showed that the difference in MVD between group A and group B was statistically significant (P < 0.05).

Bio-Oss seemed to induce an increase in MVD that reached a higher value after 6 months. The percentage of vessels positive to VEGF was higher in group A than in group B. Our data also showed a higher percentage of vessel and stromal cells positive to VEGF and higher MVD values in areas where there was newly formed bone compared with areas where maturation processes were occuring, and this fact could point to a close spatial relationship between angiogenesis and osteogenesis.