Introduction
partial dentures, edentulous mandibular arches, MIs, RPD, RPDs, tooth
SECONDARY, ATROPHIED, LEAKAGE
In jaws with few remaining teeth or unfavorable distribution between quadrants, strategic dental implants can serve as supplementary abutments for a symmetric support and more stability of removable partial dentures (RPD) [Unfortunately, conventional two-piece implants are cost-intensive and sometimes require bone augmentation procedures in narrow alveolar ridges. One-piece mini-implants (MIs) with diameters of 1.8 to 2.9 mm are mainly indicated in atrophied ridges with insufficient width to stabilize removable dentures. Thus, MIs may reduce the invasiveness of the surgical intervention with subsequently less postoperative morbidity and the primary treatment cost [Because of the one-piece design, a total no-load secondary osseointegration is not possible in the edentulous jaws as their main indication. However, this design should prevent microbiological leakage into the surrounding implant tissue [Primary stability seems to be a key factor for successful osseointegration, especially for immediately loaded implants [According to some reviews, MI-supported overdentures are a viable and safe treatment option for edentulous mandibular arches with mid-term survival rates > 90%, which is similar to standard-diameter implants [Meanwhile, a 3-year randomized clinical trial (RCT) was completed, comparing immediate with delayed loading of strategic MIs under existing RPDs with unfavorable tooth distribution [The aims of the present explorative analyses were (1) to describe the longitudinal stability values for MIs under different loading conditions, (2) to estimate the MI survival rates, and (3) to evaluate whether PTVs can predict MI losses. We hypothesized less initial MI stability and more MI failures in the immediate than in the delayed loading group as in the study protocol [