Effects of Marginal Bone Loss Progression on Stress Distribution in Different Implant–Abutment Connections and Abutment Materials: A 3D Finite Element Analysis Study

Abstract

Peri-implantitis is a common implant-supported prosthesis complication, and marginal bone loss affects the stress distribution in implant systems. This three-dimensional finite element analysis study investigated how bone loss affects the implant assembly; in particular, models including two implant systems with different connection systems (external or internal hexagon), abutment materials (titanium or zirconia), and bone loss levels (0, 1.5, 3, or 5 mm) were created. We observed that the maximum von Mises stress distinctly increased in the groups with bone loss over 1.5 mm compared to the group without bone loss, regardless of the connection system or abutment material used. Moreover, the screw stress patterns with bone loss progression were determined more by the connection systems than by the abutment materials, and the magnitude of the stress on the fixture was affected by the connection systems with a similar pattern. The highest stress on the screw with the external hexagon connection system increased over 25% when bone loss increased from 3 to 5 mm, exceeding the yield strength of the titanium alloy (Ti–6Al–4V) when 5 mm bone loss exists; clinically, this situation may result in screw loosening or fracture. The highest stress on the fixture, exceeding the yield strength of pure titanium, was noted with the internal hexagon connection system and 1.5 mm bone loss. Titanium and zirconia abutments—both of which are clinically durable—presented similar screw and fixture stress patterns. Therefore, clinicians should pay more attention to maintaining the peri-implant bone to achieve the long-term stability of the implant-supported prosthesis.

Bone Regeneration and PEEK Implants in Maxillo-Facial Surgery and Neurosurgery: A Multidisciplinary Study

“…Titanium implants, while studies comparing different materials for craniofacial reconstruction are still limited, appear to be associated with increased donor site comorbidity, including bone resorption [35]. Countless studies have demonstrated that implants crafted from specific materials, such as titanium alloys, may induce peri-implant bone resorption attributable to stress shielding phenomena [36,37]. Stress shielding is a biomechanical phenomenon that leads to adaptive changes in bone strength due to the altered distribution of physiological loads on the bone, potentially leading to implant loosening.…”

Bone Regeneration and Polyetheretherketone Implants in Maxillo-Facial Surgery and Neurosurgery: A Multidisciplinary Study

“…Factors influencing this phenomenon include not only the material but also the design, mechanical loading, and notably, the interface between the implant and the periosteum. Titanium implants, while studies comparing different materials for craniofacial reconstruction are still limited, appear to be associated with increased donor site comorbidity, including bone resorption [39]. Countless studies have demonstrated that implants crafted from specific materials, such as titanium alloys, may induce peri-implant bone resorption attributable to stress shielding phenomena [40,41].…”

The impact of different cone-angle implant-abutment relationships on the long-term success of implant restorations

“…Both phenomenons lead to failure of implant restorations [21][22][23]. There are several publications investigating the mechanical behaviors of the implants with the Finite Element Analysis (FEA).…”

“…In the study of Lin et al, a FEA method was to investigate the type of contact between implant and peri-implant hard tissues for which the distribution of masticatory forces is more uniform. They found that the von Miss stress distribution is most uniform for the tapered connection implant -abutment [22].…”