Implementation of Contact Definitions Calculated by Fea to Describe the Healing Process of Basal Implants

Abstract

Aims:Bone structure around basal implants shows a dual healing mode: direct contact areas manifest primary osteonal remodeling, in the void osteotomy-induced spaces, the repair begins with woven bone formation. This woven bone is later converted into osteonal bone. The purpose of this study was to develop a model to accurately represent the interface between bone and basal implant throughout the healing process. The model was applied to the biological scenario of changing load distribution in a basal implant system over time.Methods: Computations were made through fi nite element analysis using multiple models with changing boneimplant contact defi nitions which refl ected the dynamic nature of the interface throughout the bony healing process. Five stages of bony healing were calculated taking into account the changes in mineral content of bone in the vicinity of the load transmitting implant surfaces.Results: As the bony integration of basal implants proceeds during healing, peak stresses within the metal structure shift geographically. While bony repair may still weaken osteonal bone, woven bone has already matured. This leads to changes in the load distribution between and within the direct contact areas, and bone areas which make later contact with implant.Conclusions: This study shows that basal implants undergo an intrinsic shift of maximum stress regions during osseointegration. Fatigue testing methods in the case of basal implants must therefore take into account this gradual shift from early healing phase until full osseointegration is achieved.

A three dimensional finite element study on dental implant design

“…A novel approach for modeling different interactions between cortical and cancellous bone was proposed [17,18]. This approach has been used for describing different stages of osseointegration and remineralization.…”

Bendable vs. Angulated Dental Implants: Consideration of Elastic and Plastic Material Properties Based on Experimental Implant Material Data and Fea

“…Hence the results are valid only for basal implants immediately after the implant placement, in cases where the implant is placed in highly mineralized, cortical bone providing a rigid fi xation of the baseplate with no contact between the vertical implant part and the bone. The situation during the dual process of osseointegration of a basal implant has been described for non-angulated, unbent implants and oblique loading 5 . However, calculations for angulated or bent osseointegrated implants and the determination of forces acting on the bone while implants are bent, remain to be performed in future.…”

“…In previous articles we created models to describe the interaction between bone and basal implants using the method of fi nite element analysis. Thereby we proposed a novel approach for modelling diff erent interactions between cortical and cancellous bone 4,5 . This approach has been used for describing diff erent stages of osseointegration and remineralization.…”

Immediate-Functional Loading Concept With One-Piece Implants (Beces/Beces N/Kos/Boi) in the Mandible and Maxilla- A Multi-Center Retrospective Clinical Study

“…In previously published studies on (Cortically anchored) lateral basal implants, an immediate function concept for the edentulous mandible was presented with up to 11 years clinical follow-up. [6,7,8,9] Although the technology of lateral basal implants had proven to be successful even over such a long observation period, the technique never penetrated the market significantly. This is owed to strong opposition of traditional screw implant manufacturers and their protagonists at universities.…”

“…These theoretic findings however, do not take into account changes in the periimplant mineralization in the postoperative phase, which is directed by the functional loading of every single implant. 8 Bending the necks of dental implants lead to internal stresses in the area of the implant shaft and the process of the inserted implants will impose enormous forces onto the bone. Assuming that all other parameters are equal, bendable (Basal) implants show a more even stress distribution along the vertical implant region than identically shaped implants with a machine-angulated area.…”