Oral function of implant-assisted removable partial denture with magnetic attachments using short implants

Background and aim: In recent years, implant-assisted removable partial denture (IARPD) has been widely used in clinic. Although it has been reported that IARPD could significantly improve masticatory function, there is no research regarding masticatory function of IARPD with magnetic attachments using short implants. Therefore, the aim of this study was to evaluate the oral function of IARPD with magnetic attachments using short implants. Methods: Thirty participants who had mandibular Kennedy classification I or II with three or more distal extension missing teeth were recruited. The period of using conventional removable partial denture before implant placement was defined as stage 0. After treatment planning, the implant with 6 mm in length and 4.1 mm in diameter (Straumann SLActive Implant Standard Plus RN) was placed in the most distal edentulous space with adequate buccolingual bone width. The placed implants were covered by healing caps and the mucosal surface of the denture corresponding to the healing caps was relieved. At the end of the unloading period, the denture was relined to contact with the healing caps (stage1). Four weeks later, one or two magnetic attachments (Magfit) were attached to IARPD (stage2). Evaluation for outcomes was performed at stage 0, stage1 and stage 2. The outcomes were mixing ability by Xylitol Masticatory Performance Evaluating Gum, comminuting ability by Test Gummy Jelly for Evaluating Masticatory Performance, maximum bite force and occlusal contact area by Dental Prescale. The Wilcoxon signed-rank sum test and Bonferroni’s correction were used to evaluate differences between stages for each outcome. All statistical analyses were performed using statistical software SPSS ver.22 at a significance level at p=0. 05. Results: The data of 27 participants who completed evaluation at stage 2 were analyzed. There were significant differences in comminuting ability and occlusal contact area between stage 0 and stage 2, and between stage 1 and stage 2. Regarding the maximum bite force , there was significant difference between stage1 and stage2. There was no significant difference in mixing ability between 3 stages. Conclusion: Within limitation of this study, this result suggested that IARPD with magnetic attachments using short implants could improve oral function.