Effect of implant surface characteristics on osseointegration in the ilium of dogs

Kwak, Jae Woo; Kim, Tae Hee; Park, Hong Ju; Oh, Hee Kyun

Abstract

The failure rate of implant is high in the posterior maxilla which has a poor quality of bone. Although the bone quality can affect osteointegration rate, additional variables, such as the implant surface characteristics can also influence the implant success. The purpose of this study was to compare the effect of 4 different implant surface characteristics on osteointegration in the dog's iliac bone which has thin cortical bone and loose trabecule. Three mongrel dogs, wighing 15 kg or more, were used. The animals were divided into 4 groups on the basis of implant surface characteristics: control group, animals which the machined, smooth surface AVANA implants were placed in the iliac crest (n=3); RBM group, animals which RBM surface AVANA implants were placed (n=3); HA group, animals which HA-coated Steri-Oss implants were placed (n=3); and SLA group, animals which SLA Bicon implants were placed (n=3). These implants were placed in the iliac bone of dogs under general anesthesia. The animals were sacrificed at 8 weeks after implantation. The radiographs were taken and the undecalcified specimens were prepared for histological examination and histomorphological analysis of implant-bone contact ratios. Macroscopically there were neither an infection at the implant site nor an exposure of implant. Radiographically the good osteointegrated findings were observed around implants. Histologically, direct bone apposition to implant surface was found in all groups. More mature and dense bone was observed in the bone-implant interface of surface-treated groups than control group. Histomorhologically the average bone-implant contact ratio was highest in HA group (82.5+/-12.4%), in the order of SLA group (66.3+/-18.2%), RBM group (51.1+/-12.3%), and control group (50.1+/-18.1%) respectively. The ratios of HA (p<0.01) and SLA (p<0.05) groups were significantly higher than control group. These results indicate that the better osseointegration can be obtained in the rough surfaced implants, such as HA coated or SLA -treated implants than the machined, smooth surfaced implants.