Comparison of Radiographic Bone Height Assessments in Panoramic and Intraoral Radiographs of Implant Patients

Purpose: To compare the ability of 2 radiographic methods, intraoral and panoramic radiography, commonly used in private practices following implant treatment to provide reliable information about the level of peri-implant marginal bone. An additional aim was to compare the inter- and intraobserver reliability. Materials and Methods: Patients with implants placed in the mandible in 10 private practices were studied retrospectively. Postoperative intraoral and panoramic radiographs were evaluated at a university oral radiology clinic. Two observers, a specialist in oral and maxillofacial radiology and a specialist in oral and maxillofacial surgery, assessed the bone level, and the thread at which the marginal bone seemed to be attached was registered for the distal and mesial surfaces of all implants at 2 assessments several weeks apart. Kappa statistics was used to compare the agreement between assessments, observers, and methods of radiography. Results: Intraobserver agreement was good or very good, while interobserver agreement was predominantly moderate. The agreement rate between the methods was also moderate. Seven percent of the sites were not possible to assess, with a small difference in favor for panoramic radiographs. In the assessment of the panoramic radiographs, the radiologist found more sites too difficult to assess than the surgeon did. Conclusions: In this study, panoramic radiographs were found to be as reliable as conventional intraoral radiographs when used to assess the point of bone attachment to implant threads. Intra- and interobserver agreement were reliable but not excellent. The radiologist was more successful in finding sites where the bone level was impossible to assess accurately. Keywords: bone height assessment, dental implants, intraoral radiographs, observer agreement, panoramic radiographs