성견에서 임프란트 주위에 골결손부를 형성한 후 혈소판 풍부 혈장과 혈소판 풍부 섬유소의 효과

Abstract

ABSTRACT

Effect of PRP and PRF on peri-implant bone defects in dogs

Jeong, Kyung-In Advisor : Prof. Kim, Su-Gwan, D.D.S., Ph.D. Department of Dentistry, Graduate School of Chosun university

Purpose: The purpose of this study was to evaluate the effect of tooth ash and platelet rich fibrin(PRF) or platelet rich plasma(PRP) graft into bone defect around implants in bone formation.

Materials and Methods: Six adult dogs with the weight of 10-15 kg were experimental subjects. Before placing implants, the extracted teeth from the mandible of adult dogs were referred to Korea Teeth Bank for tooth ash treatment. Graft materials were made into particulate type. 48 tapered type implants with the diameter of 3.7 mm and the length of 10 mm and the surface treated with hydroxyapatite(HA) coating were used as implant fixtures and they were divided into two groups, a 4 weeks and a 8 weeks group. Using trephine bur, four bone defects with the diameter of 8 mm and the depth of 5 mm were formed and implants were placed in the femur of adult dogs. In the control group, bone graft was not performed. In the experimental group 1, tooth ash was grafted. In the experimental group 2, mixture of tooth ash and PRP with the ratio of 1:1 by volume was grafted. In the experimental group 3, mixture of tooth ash and PRF with the ratio of 1:1 was grafted in defect area. After 4 and 8 weeks each, the dogs were sacrificed. Using Osstell™ mentor on the time of placement and after the sacrifice, the implant stability was evaluated and using histopathological examination, the amount and rate of new bone formation was evaluated.

Results: In the 4 weeks group of experimental group 3, two implants were lost due to poor initial stability. However, the rest 46 implants were all successfully fixed. In all groups, implant stability was increased significantly at the time after the sacrifice compared to the that at the time of placement. And implant stability was increased in experimental group 1 than control group, experimental group 3 than group 1 and control group. But there were no significant difference between experimental group 1 and 2, 2 and 3. As the result of histomorphometric examination, the new bone formation rate in the experimental group 3 of the 4 weeks group was significantly higher than that in the control group. Also, in the 8 weeks group, the significant increase of new bone formation was confirmed in the experimental group 3. The new bone formation between control group and experimental group 2 and 3 didn't show statistically significant difference.

Conclusion: In this study, bone graft method using the mixture of tooth ash and PRF was comfirmed to increase new bone formation compared to the method using PRP. Also, it was confirmed that this effect was more prominent in the initial stage of bone graft.