Silicone attachment for avoidance of bone tissue overloading in single implant-retained denture

Purpose: The application of single implant-retained dentures (SIDs) is still rare. It seems that the reason of that is the fear of the overloading of a bone tissue around the implant that alone bears the occlusal loads. In this paper, stress level in the bone tissue around the single mini-implant that alone retained the lower denture was investigated. This stress level depends on the denture joint (the attachment) to the implant. Design/methodology/approach: 3D finite element method (FEM) analysis was used in order to determine the transmission of occlusal loads between mucous membrane foundation and the bone tissue around small diameter (1.8 mm) implant. Standard rotationally and axially mobile denture attachments were compared with the laterally compliant silicone attachment. Oblique mastication loads were assumed for the purposes of a better simulation of realistic conditions. Findings: Both types of standard attachments, rotationally and axially mobile, born remarkable values of oblique mastication force. This load results in a high stress in the bone tissue around a single mini-implant, in the area convergent with clinically observed “funnel-shaped” marginal bone loss around the implant neck. The silicone attachment reduced the loading to a level, which did not create any stress that would be dangerous for the bone tissue. Research limitations/implications: In the FEM model a perfect denture adherence to mucous foundation was assumed and a perfect joint between the implant and bone tissue. Further simplification were the linear isotropic characteristics of used materials. Practical implications: The use of single mini-implants requires the highest quality of the alloy and surface finishing due to the risk of fatigue cracks in case of a quickly progressing “funnel-shaped” bone loss. The silicone attachment provided better utilization of the mucous membrane support that significantly improves safety of implant and diminishes the requirements of bone foundation conditions for an implantological treatment. Originality/value: Presented was a possibility to achieve a much more reliable SID by means of used silicone attachment.