Evolution of in vivo assessed retention forces in one‐piece mini dental implant‐retained mandibular overdentures: 5‐Year follow‐up of a prospective clinical trial

Abstract

Background The evolution of retention forces in one‐piece mini dental implants (MDIs) retaining implant overdentures (IODs) is of major importance, as the male parts cannot be exchanged, due to the implant design. Purpose To report the evolution of retention forces of one‐piece MDIs, retaining mandibular IODs with ball/ O‐ring attachments during 5 years assessed in vivo. Materials and Methods Four MDIs were installed in the interforaminal region and immediately loaded using the existing mandibular complete denture. Directly post‐op, at the 1‐year and the 5‐year follow‐up, the retention forces were assessed with a validated strain gauge at each implant site separately. Results At the male part, changes could only be observed at implant site 34: During the first year, there was a statistically significant increase, whereas the retention forces were decreased at the 5‐year follow‐up. At the female part, retention forces decreased significantly over time. Baseline values could be reestablished by exchanging the O‐rings. The changes of the retention forces were more obvious in the posterior, compared to the anterior implants. Conclusions Retention forces at the female part decrease significantly over time, when retaining mandibular IODs by MDIs with ball/ O‐ring attachments. Baseline values can be reestablished by exchanging the O‐rings. At the male part, changes of retention forces depend on the implant location.

Clinical outcomes and bone‐level alterations around one‐piece mini dental implants retaining mandibular overdentures: 5‐year follow‐up of a prospective cohort study

“…We also observed no influence of implant position on ΔMBL values. Another publication on the same study cohort, focusing on retentive forces of the IODs at the male and female parts, showed a significant loss of the mean retention force at the male part only at implant site 34 (Abou‐Ayash et al, 2019). Interestingly, the highest mean ΔMBL was found at the same implant site, which confirms the theory that the forces at this site might have been different relative to the other implant sites.…”

Factors and clinical outcomes for standard and mini-implants retaining mandibular overdentures: A systematic review and meta-analysis

“…1-10 Among the possible treatment choices, the implant-retained mandibular overdenture (IOD) can differ depending on the design, position, and implant number and according to the patients' clinical presentation. 2,[11][12][13][14] Despite the benefits of IODs, patients might decline the treatment because of cost, fear of oral surgery, or psychological issues. 15,16 Moreover, standard-diameter implants might not always be clinically possible for anatomic or financial reasons.…”

O-Ring Attachments on One-Piece Mini Dental Implants: In-Vitro Analysis of Retention Force Reproducibility Using Different Pristine Matrix-O-Ring Combinations

“…1b), as described in a previous study. 17 The disconnections were not performed at a predefined speed.…”

“…[14][15][16] Under in-vivo conditions, it has been shown that the initial retention forces in one-piece MDI retained overdentures can be reestablished, just by exchanging the O-rings, even after a 5-year period, which proves the theory of the male parts' and matrices' low wear in this kind of system. 17 But due to the pronounced deformation of O-rings during the connection and disconnection from patrices, the reproducibility of the retention forces, even of pristine O-rings has been questioned. 14 Furthermore, the influence of the matrix-and the O-ring diameter on the retention forces and its' reproducibility has not been scientifically evaluated.…”