ACCURACY OF RADIOGRAPHIC DIAGNOSIS OF PERIIMPLANT RADIOLUCENCIES - ANIN-VITRO EXPERIMENT

The absence of a peri-implant radiolucency on radiographs is used as a criterion for implant success. The purpose of the present study was t o evaluate the accuracy of diagnosing peri-implant radiolucencies usin g an experimental model. Astra Tech fixtures were inserted into 20 bon y specimens. Later, the fixtures were removed and the prepared cavitie s were enlarged in 2 steps. The specimens were radiographed under stri ctly standardized circumstances in the 3 stages (''press-fit'' = simul ated osseointegration, and ''0.1 mm space'' and ''0.175 mm space'' = s imulated connective tissue layer). All specimens were radiographed wit h 2 vertical angulations (0 degrees and 15 degrees). Ten observers rea d the radiographs and evaluated bone-implant relationship on a 5-point scale. The interobserver agreement was low. Specificity was remarkabl y low, and sensitivity was moderate. A significant difference in diagn ostic accuracy was found for 0.175 mm peri-implant space compared to 0 .1 mm space. The diagnostic accuracy was found to be highest for 0.175 mm peri-implant space specimens. It is concluded, that radiography se ems to be an unreliable method for diagnosing peri-implant spaces, alt hough accuracy improved at increasing space widths. Strict orthogonal projection angles did not improve diagnostic accuracy.