Evaluation of the effects of diagnostic radiation on titanium dental implant osseointegration in the micropig.

The effect that diagnostic radiation may have on peri-implant supporting alveolar tissues is not well understood. Fifty-four (54) titanium dental implants were inserted into the posterior mandible of nine micropigs. At implant placement surgery, 18 implants were exposed to either 2 (diagnostic) or 10 (excessive) doses of diagnostic radiation; the remaining 36 implants served as controls. Fourteen weeks after implant placement, standardized clinical radiographs were taken, pigs were euthanized, and implants with supporting alveolar tissues were prepared and examined by light and scanning electron microscopy (SEM). Ninety-seven sections were evaluated by SEM for morphometric and morphologic analyses. The mean percent of implant length in contact with bone was 47% for the controls and 53% for the implants receiving radiation. Five implants were lost during the initial healing phase and four implants were clinically mobile at time of euthanasia, giving a success rate of 83% (45/54). Correlative light microscopy of peri-implant supporting tissues revealed no distinct differences between the microvasculature of controls versus implants exposed to radiation. Standardized clinical radiographs revealed crestal saucerization in both control and radiated implants. This study revealed no statistically significant difference for the percent of implant length in contact with alveolar bone for controls or implants exposed to 2 or 10 doses of diagnostic radiation at implant placement time.