Microradiographic Study of Retrieved Craniofacial Osseointegrated Implants

Abstract

In this study 18 screw-shaped extraoral osseointegrated implants retrieved from 10 patients were analyzed. The reasons for retrieval were: unexplained pain (n = 4); inability to cope with the implants (n = 2); fracture of the central screw (n = 2); skin penetration problems (n = 1), and trauma (n = 1). Retrieved implants were trephined with a border of surrounding bone, fixed, embedded in epon plastic, ground and processed for microradiography. The study group comprised 6 males and 4 females with a mean age of 53.4 (range 9–81) years. All implants were clinically stable at the time of removal, and the mean osseointegration time was 3 (range 1–5) years. Six implants were removed from the temporal bone, 5 from the frontal bone, and 7 from the maxilla. By microradiography, it was found that all retrieved implants were surrounded by a lamellar type of bone with haversian systems, vascular channels, osteocyte lacunae, and in some specimens regeneration and resorption areas. Bone metal contact was estimated to vary between 27 and 83%. Bone metal contact was lower in the frontal bone compared to the temporal bone or maxilla, and was further reduced after preoperative irradiation. Longer osseointegration time increased bone metal contact, as did increased age up to 60 years. It is concluded that extraoral osseointegrated implants in humans may integrate morphologically as well as clinically. By microradiography it was possible to define bone metal contact in the region of implant installation.

Radiotherapy, osseointegration and hyperbaric oxygen therapy

“…Bone–metal contact varied between 30 and 70%. In a study of 18 osseointegrated implants retrieved from 10 patients, three of the implants were from an irradiated patient (22). It was found that bone–metal contact was reduced (27–35.6%) compared to nonirradiated implants of the same region, which showed 44–46.6% bone–metal contact.…”

Retrieved Implants from Irradiated Sites in Humans: A Histologic/Histomorphometric Investigation of Oral and Craniofacial Implants

“…In a study of 18 osseointegrated implants retrieved from 10 patients, three of the implants were from an irradiated patient. 29 It was found that BMC was reduced (27)(28)(29)(30)(31)(32)(33)(34)(35).6%) compared to nonirradiated implants of the same region that showed 44-46.6% BMC. As a comparison average, the BMC for loaded extraoral implants was estimated to be 62% by Bolind and colleagues.…”

Bone‐impacted fibular free flap: Long‐term dental implant success and complications compared to traditional fibular free tissue transfer

“…Factors influencing dental implant success or failure can be classified as extrinsic or intrinsic. Extrinsic causes cited in the literature include contiguous use of local carcinogens, such as tobacco, higher doses of radiation, and chemotherapy . Intrinsic causes impacting dental implant failure are that of soft tissue status, shorter implants, and bone stock .…”