New formation of periodontal tissues around titanium implants in a novel dentin chamber model

Abstract

Direct bone-to-implant contact, defined as "osseointegration", is considered most optimal for long-term stability and survival of dental implants. However, the possibility of the formation of a tooth-like attachment apparatus around implants has also been demonstrated. The purpose of this study was to explore the formation of periodontal tissues around titanium implants using a novel and unique experimental model. After resection of the crowns of the maxillary canine teeth in nine mongrel dogs, the roots were hollowed to a depth of 5 mm leaving a thin dentinal wall. Slits were prepared in the cavity wall to create passages from the chamber to the periodontal ligament area. A custom-made, titanium implant was placed into the center of each chamber. Machined, titanium plasma sprayed (TPS) and sand blasted with large grit and acid attacked (SLA) surfaces were used. A collagen barrier was placed over the submerged chamber. Following 4 months of healing, jaw sections were processed for histology. Newly formed periodontal ligament, alveolar bone, and root cementum filled the space between the implant and the wall of the chamber. Ingrown bone was neither in contact with dentin nor with the implant. Thus, an interposed soft connective tissue layer was present. Healing by fibrous encapsulation was observed around most implants. However, cellular cementum was deposited on one TPS and one SLA implant and on the dentinal walls of the chamber. This study shows a remarkable capacity for new periodontal tissue formation at a site where no such tissues ever existed. Maintenance of original periodontal tissue domains most likely prevented osseointegration of the implants. The cementum layer deposited on two implants was likely formed through cementoconductivity rather than by differentiation of periodontal ligament cells upon contact with the implant surface.

Ridge Preservation with Modified “Socket-Shield” Technique: A Methodological Case Series

“…In other words, it should be attempted to achieve an implant position where all boundaries are formed by bone, since, according to current and established principles of osseointegration [31], only direct bone-implant contact without fibrous tissue or other dental materials is accepted as a successful implant interface. If this is the case, complete osseointegration of the implant will be achieved and the formation of a fibrous tissue sheath around the implant [18,19], can be avoided. Here again it has to be mentioned as a limitation that such data could not be collected as part of this case series.…”

“…Hürzeler et al [18] also demonstrated that the intentional preservation of the coronal buccal root portion can help to ensure the physiological preservation of labial and buccal bone structures if the implant is placed in contact to this natural tooth fragment (shield). However, this approach is associated with certain risks, such as the formation of a peri-implant periodontal membrane [19] or the development of peri-implant infections, as well as resorption associated with the usual biological long-term complications that may occur. These occur especially in the presence of pre-exiting or developing periodontal or endodontic infections or inflammations of the retained tooth fragments.…”

Ultrastructure of the Interface between Periodontal Tissues and Titanium Mini-Implants

“…The possibility of cementoblasts covering the cementum of adjacent roots, after having migrated to form the cementum-like layer, also should be considered. 25 The cementum-like layer contained some collagen fibrils into its milieu; this is somewhat similar to the acellular extrinsic fiber cementum that is formed by fibroblasts during cementogenesis. 20 Nevertheless, although the layer had a cementum-like appearance, it did not contain inserted collagen bundles (Sharpey's fibers), leaving it toward the adjacent periodontal ligament.…”

Implant Insertion Methods and Periimplant Tissues – Experimental Study

“…The discovery of a periodontal ligament around titanium implants opens new perspectives in implantology. Parlar et al (Parlar et al, 2005) performed unique experiment on mongrel dogs to explore the formation of periodontal tissues around titanium implants using maxillary canine roots. They created chambers within the roots and prepared slits in the cavity walls to connect the chamber to the periodontal space.…”