Clinical evaluation of implant overdenture with self adjusting magnetic attachment

Objectives: The purpose of this study was to evaluate clinical performance of implant-supported overdentures using newly developed self-adjusting type magnetic attachments with subjective and objective parameters.Methods: Five implant overdenture patients with informed consent using at least one magnetic attachment (Magfit-IP, Aichi Steel Corporation, Tokai City, Japan) were included in this study. The newly developed magnetic self-adjusting attachment enables to compensate for the resiliency of mucosa up to 0.4 mm underneath the denture base and allow the rotational movements up to 8 degrees. It can also compensate for the shrinkage of the resin material during denture fabrication. Observation periods were from 6 months to 1.5 years. Subjective evaluations of patients were recorded by questionnaires using visual analog scale (VAS) regarding retention, stability, comfort, masticatory function, and food selection as well as ease of cleaning. Objective evaluation was performed with a standard protocol including corrosion, abrasion, denture retention, and frequency of maintenance such as repair or adjustments. Statistical analysis was performed with t-test (p<0.05).Results: Subjective evaluation indicated that magnetic attachments have statistically higher rating scale with VAS in stability, comfort, masticatory function, and food selection as well as ease of cleaning (p<0.05), while there was no difference in retention. Objective evaluation indicated that there were no incidents of corrosion, although slight abrasion of the keeper surface and loss of retention due to bone. resorption under the denture base were found in two cases.Conclusions: Within the limitation of this study in terms of the number of patients and observation periods, it was suggested that magnetic attachments are effective for retaining implant-supproted overdentures.