Bone scintigraphy and SPECT in the evaluation of the osseointegrative response to immediate prosthetic loading of endosseous implants: a pilot study.

PURPOSE Several recent medical reports have focused attention on the possible application of skeletal scintigraphy imaging in odontostomatology. The aim of the present report was to assess the influence of immediate prosthetic loading on peri-implant osteoblastic activity through bone scintigraphy. MATERIALS AND METHODS Implants were placed in 2 healthy women. A nuclear medicine investigation with single-photon emission-computed tomography (SPECT) was performed for both patients at 30 and 90 days after implant placement. The study was completed with acquisitions of planar images of the skull in an anterior view and the use of regions of interest (ROIs) of the same size in the area corresponding to immediate loading and in the opposite hemimandible (at the control sites). Count density ratios (counts/pixel) obtained from each ROI were used for a quantitative/relative assessment. Tomographic images were evaluated with a qualitative method. The spatial resolution of the reconstructed tomograms and of the planar images was approximately 7 mm. RESULTS Routine planar methodology provided a direct measure of cellular activity of the examined areas. The difference in count density ratio registered from the same ROI between the first and the second scintigraphy revealed the course of peri-implant osteoblastic activity, which was very high in the first month and then declined during subsequent months. DISCUSSION AND CONCLUSION In spite of the small number of involved patients, the results obtained from this pilot study suggest that nuclear medicine may hold possible advantages in implant dentistry for those who seek to clarify the still unknown aspects of osteoblastic activity.