[Establishment and experimental study of alveolar preservation before dental implantation in Beagle dogs]

To establish the model of alveolar ridge preservation after tooth extraction for dental implant replacement, and to observe the effect of tissue engineered bone on osseointegration.

Isolated BMSCs were expanded and osteogenically induced in vitro. The tissue engineering complex was constructed with BMSCs/A-PCPC in vitro. Six extraction sockets, with three on each side, were created in the mandibles of four Beagle dogs by extracting the second, third and fourth premolars. BMSCs/A-PCPC were placed on one side of the extraction sockets, while autogenous bone, A-PCPC and nothing were placed on the other side as control. X-ray and CT scans were conducted 1day, 4 and 12 weeks after operation to detect the change of the alveolar ridge. The bone of sockets were harvested at 8-week post-implantation and subject to histological for evaluating. SPSS17.0 software package was used for data analysis.

Radiographs demonstrated higher radiodensity in group of complex than in simple materials group, autogenous bone group after 4 weeks. Hard tissue biopsy at 12-week showed that bone activity of BMSCs/A-PCPC complex was better than the other groups. Spiral CT analysis showed that alveolar ridge of each group experienced a certain degree of absorption. At 12-week, the alveolar ridge height reduction values in A-PCPC group was smaller than in A-PCPC group, autogenous bone group and blank group (P<0.05).

The BMSCs/A-PCPC complex is favorable for preservation of alveolar ridge.