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.

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.