Ultrastructural analyses of the attachment (bonding) zone between bone and implanted biomaterials

Abstract

This report presents transmission electron and high voltage transmission electron microscopic observations of bone and associated remodeling tissues directly interfacing with endosteal dental implants. Undecalcified interfacial tissues were serially sectioned from mandibular samples encasing 60 implants placed into 30 dogs. Two-dimensional ultrastructural analyses and three-dimensional stereology showed that osteogenesis adjacent to dental implants is a dynamic interaction of osseous cells and a collagenous fiber matrix. This study showed that the interfacial bone consists of a mineralized collagen fiber matrix associated with an inorganic (hydroxylapatite) matrix. This study suggested that an unmineralized collagen fiber matrix initially is laid down directly at the implant surface, and that this matrix then is mineralized. Osteoblasts interacted with this matrix, eventually becoming encased within developing lacunae during the remodeling process. This process formed the cellular (osteocyte) aspects of the developed bone. Osteocyte processes extended through canaliculi directly to the implant surface. Apparently, these processes also were entrapped within canaliculi during the mineralization events. At times, these processes paralleled the implant surface. The bone-implant interfacial zone was primarily fibrillar (both mineralized and unmineralized) in morphology, with an electron-dense, ruthenium positive deposition. This electron-dense material was approximately 20 to 50 nanometers in thickness, and only this thin layer separated the remodeled mineralized bone from the implant.

In silicobiology of bone modelling and remodelling: regeneration

“…The principal mechanisms underlying the healing around implants are comparable to those of fracture healing (Schenk & Herrmann 1984;Gross 1988;Plenk & Zitter 1996;Overgaard 2000), although this view has triggered much debate since some authors have suggested that the presence of an implant induces a different healing mode (Schwartz et al 1997;Steflik et al 1998).…”

Quantitative Evaluation of Calcium Phosphate on Surface of Titanium by X-ray Fluorescence Analysis

“…[1][2][3] However, when immersed in vivo, they exhibit poor adhesion with the surface of bones because of their low biocompatibility. 4) Recently, various surface treatments employed for the improvement of hard-tissue compatibility have been investigated. [5][6][7][8][9][10][11][12][13] For the evaluation of hard-tissue compatibility in vitro, an immersion test has often been conducted using a simulated body fluid.…”

Mineralization at the interface of implants

“…This matrix is then mineralized to a state of mature bone mineral. A thin 20-50 nm electron-dense deposit was found to separate the implant from the mineralized bone matrix 97 . The electrondense zone, suggested to have a 'glue'-like function, and not consistenly confirmed by other authors 67 , requires further investigation.…”