Detection of peri-implant bone changes with axial tomosynthesis

Tuned aperture computed tomography was used to assess bone defects at implant sites that are normally : obscured in conventional periapical projection. Titanium implants were placed in incise;, premolar, and molar was of an edentulous dry human mandible. The alveolar crest adjacent to each implant was circumferentially grooved with progressively larger round burs (no. 1/4 to no. 6). After each increment of bone removal, axial tuned aperture computed tomography slice images were produced. From these, digital subtraction images were generated with incremental and baseline slices. A panel of eight dentists reviewed randomized pairs of images that showed defects that differed by a Single bur size. Images were masked to limit observation to mesial, distal, facial, or lingual regions. Observers accurately identified larger lesions in 76% of the unsubtracted tuned aperture computed tomography images and in 90% of the subtracted images. Logistic regression analysis suggested significant differences as a result of lesion size (p < 0.036) and imaging modality (p < 0.020).