SPECT in the long-term evaluation of osteointegration in intraoral and extraoral implantology.

Scintigraphic methods used in intraoral and extraoral implantology allow the evaluation of bone metabolism in the peri-implant zones, providing anatomic images and functional dynamics information on the osteointegration process. Twenty-five patients who underwent implantation operations for the application of intra- and extraoral prostheses were studied using technetium 99 m single photon emission computed tomographic (SPECT) procedures to evaluate osteointegration dynamics at 3 weeks, and 3, 6, 12, and 24 months. The study demonstrates that radiation emission peaks 3 weeks after surgery with the maximal bone remodeling activity and 6 months after surgery after the functional loading of the implants only in intraoral fixtures. High uptake past the eighth month after surgery has never been detected and must be considered abnormal. SPECT offers the possibility of obtaining a three-dimensional reconstruction of the photon emission of selected structures. The use of these nuclear medicine methods in addition to traditional-type radiological procedures introduces new possibilities, although still in the clinical experimentation phase, for early diagnosis and inserted implant prognosis.