Uncontrolled Diabetes Hinders Bone Formation Around Titanium Implants in Rat Tibiae. A Light and Fluorescence Microscopy, and Image Processing Study

This study examined the influence of diabetes mellitus on bone formation around cylindrical titanium (Ti) implants (1.0 mm in diameter and 1.5 mm in length) inserted transcortically and extending into the medullary canal of rat tibiae using light and fluorescence microscopies and image processing. Forty-eight male Wistar King A rats (age 5 weeks) were used in this experiment. Streptozotocin was injected intraperitoneally to induce diabetes and the serum glucose concentration was checked to ensure the induction of diabetes prior to implant placement and at the time of sacrifice. The animals were sacrificed 7, 28, 56, or 84 days after placement. Toluidine blue-stained undecalcified sections were prepared for histological observation and image analysis. The Ti implants in the control group became increasingly encapsulated with a bone layer. The implants in the diabetes-induced (DI) group were also surrounded with a thin bone layer. Abundant adipocytes were observed in the DI group as compared with the control group. Quantitative evaluation indicated that the control group showed a significantly higher percent of bone contact, and thickness of surrounding bone and area than the DI group. Consequently, the present study suggests that uncontrolled diabetes would hinder bone formation around Ti implants in rats.