Retention and wear behaviors of two implant overdenture stud-type attachments at different implant angulations

Statement of problem

Implant angulation should be considered when selecting an attachment. Some in vitro studies have investigated the relationship between implant angulation and changes in the retention force of the stud attachment, but few studies have evaluated the effect of cyclic loading and repeated cycles of insertion and removal on the stud attachment.

Mandibular implant‐supported overdentures and oral function

Objectives: Oral rehabilitation by means of implant‐retained mandibular overdentures is known to improve oral function. The aim of this study was to evaluate the long‐term effects of mandibular implant treatment on oral function. We quantified maximum bite force and masticatory performance 10 years after implant treatment. It was hypothesized that these outcome measures would not change in this period. Materials and methods: Eighteen edentulous patients were scheduled for re‐evaluation of their oral function 10 years after they had participated in a randomized cross‐over clinical trial. In that trial, they had received two mandibular implants and a new denture with successively magnet‐, ball‐socket, and bar‐clip attachments. Results: At the 10‐year follow‐up, 14 of the initial 18 patients participated in the evaluation. As a result of the implant treatment, the average maximum bite force more than doubled, from 162 to 341 N, whereas the average number of chewing cycles to halve the initial partcle size decreased from 55 to 27 cycles. No significant changes in maximum bite force and masticatory performance were observed after 10 years. However, the average maximum bite force obtained with implant‐retained overdentures is still significantly lower than that of dentate subjects (569 N). Conclusion: Maximum bite force and masticatory performance significantly increased after implant treatment and remained unaltered during the following 10‐year period. Thus, implant treatment greatly improves oral function for a long period of time. To cite this article:
van der Bilt A, Burgers M, van Kampen FMC, Cune MS. Mandibular implant‐supported overdentures and oral function.
Clin. Oral Impl. Res. 21 , 2010; 1209–1213.
doi: 10.1111/j.1600‐0501.2010.01915.x     

Comparison of patient satisfaction,quality of life,and bite force between elderly edentulous patients wearing mandibular two implant‐supported overdentures and conventional complete dentures after 4 years

This study compared two groups of patients who were elderly and edentulous, one group included subjects who had mandibular overdentures supported by two implants (Group I); the other groups wore conventional complete dentures (Group II). This retrospective study included 100 edentulous patients (50 from each group) with an average age of 67.86 years, who had been followed for 4 years. The groups were compared in terms of patient satisfaction, quality of life (QOL), and bite force. The bite force and patient satisfaction scores of Group I were found to be statistically significantly higher than Group II (p < .05). However, no statistically significant difference was found between the two groups’ QOL scores (p > .05) except on the physical pain subscale (p = .013). Based on these results, it can be concluded that after 4 years of function, subjects wearing mandibular overdentures supported by two implants had higher values for bite force and patient satisfaction scores, but similar QOL scores when compared to conventional complete denture‐wearers.     

Patient satisfaction with two designs of implant supported removable overdentures; ball attachment and magnets

Objective: The aim of this study was to compare ball and magnet attachments within implant-supported mandibular overdentures (ISMOD) using patient centred outcome measures. Our a priori hypothesis was that there is no difference in patient satisfaction between the two attachment types.
Material and methods: In this within-subject crossover randomised clinical trial, edentulous patients were recruited to the study and completed a denture satisfaction questionnaire before having two implants placed in the intraforaminal region of the mandible. They were randomly assigned to receive an ISMOD retained by either ball or magnetic attachment. After 3 months satisfaction questionnaires were repeated before attachments were changed to the alternative design. After a further 3 months patients completed final questionnaires. Patients were asked to choose their preferred prostheses and record the most influential factors in their final choice. The outcome variables of patient satisfaction were compared between baseline and the two attachment types using non-parametric two-related sample tests (Wilcoxon's signed rank).
Results and discussion: Sixteen patients completed the study. Patient satisfaction improved significantly between baseline and the new prosthesis with each attachment type for all domains of satisfaction ( P <0.05). Ball attachments provided greater satisfaction in the domains of general satisfaction, stability and ability to chew ( P <0.05). Patients' general satisfaction with ball attachment retained overdentures was greater than that for magnetic attachments; however, both designs provide significantly greater satisfaction than conventional dentures. In this study, the majority preferred to retain the ball attachment although one-third of patients actively chose the magnetic attachment.