Imaging evaluating of the implant/bone interface—an <i>in vitro</i> radiographic study

Abstract

To analyze the diagnostic accuracy of conventional and digital radiographic images and the impact of digital filters in evaluating the bone–implant interface. Titanium implants were inserted into 74 fresh bovine ribs blocks, 37 fitting tight to the bone walls (simulating the existence of osseointegration) and 37 with a gap of 0.125 mm (simulating a failure in the osseointegration process). Periapical radiographs were taken with conventional film and two phosphor plate systems [VistaScan® (Dürr Dental, Bietigheim-Bissingen, Germany) and Express® (Instrumentarium, Tuusula, Finland)]. Digital radiographs were investigated with and without enhancement filters. Three blinded examiners assessed the images for the presence of juxtaposition in the bone–implant interface using a five-point Likert scale. Sensitivity, specificity and the area under the receiver-operating characteristic curve (AUC) and its 95% confidence interval (CI) were calculated for each variable. Intraexaminer and interexaminer agreements were analyzed using Kendall's concordance test. Intraexaminer and interexaminer agreements were >0.80 for both digital and conventional images. Conventional radiographs (AUC = 0.963/CI = 0.891 to 0.993) and digital images with high enhancement filters such as Caries2 (AUC = 0.964/CI = 0.892 to 0.993), Endo (AUC = 0.952/CI = 0.875 to 0.988) and Sharpen3 (AUC = 0.894/CI = 0.801 to 0.954) showed the greatest accuracy for evaluating the bone–implant interface. Original images from both digital systems and the further enhancement filters tested showed low sensitivity for the diagnosis task tested. Conventional radiographs or digital radiographs with high-pass filters could help enhance diagnosis on implant–bone interface.