口内法X線写真による骨接合型インプラントの周囲骨の骨塩量の計測

抄録

The osseointegration type of implant is now the prevailing modality in dental implant operation. Evaluation of the jawbone is, therefore, important for patients scheduled for an implant operation. Methods like QCT and DEXA, which are currently used to measure bone mineral content in other bones, cannot be employed for quantitative evaluation of bone in the jaw. In addition, the instruments required are so expensive that they may not be practical for introduction into clinical dentistry.
To measure bone mineral content in the jawbone, we developed a TV-image analysis system using dental X-ray films.On applying this system, the following results were obtained.
1. Quantitative evaluation of bone quality could be achieved simply and rapidly by this system.
2. The relation between age and bone mineral content differed between the sexes. In all age groups examined,the mean values of bone mineral content were higher in males than in females.
3. Standard average values of mandibular bone mineral content by age and sexes could be determined. This allows screening of patients prior to implant operation.
4. The bone mineral content in bones adjacent to the site of implant, which remained unchanged after installation, was found to increase before attachment of a superstructure.
5. In contrast to the increased bone mineral content in adjacent bones, the bone mineral content in mandibular alveolar crest tended to be decreased for some time.