Validation of microfocus computed tomography in the evaluation of bone implant specimens

Microfocus computed tomography (muCT) is an emerging technique owing to its speed, full three-dimensional information, and nondestructive properties.

The aim of this study was to explore the efficacy of a muCT system (Philips HOMX 161, Philips Medical Systems GmbH, Hamburg, Germany) for visualization of the bone structure around screw-type titanium implants by comparing muCT images with their histologic homologues.

Eight screw-type titanium implants were placed in the femoral condyles of two goats. After the excised implant-bone specimens were embedded in resin, three-dimensional muCT of the excised implant and bone specimens was performed. Histologic sections were subsequently made. A total of 150 histologic sections were matched with muCT images.

Bone trabeculae were clearly visible on the muCT scans. However, bone close to the implant or present in the apical surface features of the implant could not be detected. The overall matching between muCT scans (slices) and the histologic sections was 89%.

Investigation of trabecular bone around titanium implants by muCT can be considered highly reliable for determining trabecular bone parameters, with the exception of measuring direct bone-to-implant contact.