Examining Circumferential Bone Stability Around Narrow-Diameter Implants Retaining Mandibular Overdentures: A Three-Year Longitudinal Analysis.

PURPOSE: To investigate the relationship between secondary stability and circumferential bone level of narrow-diameter implants to retain mandibular overdentures (MOs) after 1 and 3 years.

MATERIALS AND

METHODS

A total of 30 patients (19 men, 11 women) with a mean age of 67.5 years were monitored using the implant stability quotient (ISQ), and the vertical (VBL) and horizontal (HBL) bone level assessed with CBCT were measured on the four implant faces. Two-way ANOVA with repeated measures and Sidak post-hoc test were used to compare ISQ, VBL, and HBL over time and between faces.

RESULTS

The linearity and association between ISQ, VBL, and HBL were analyzed by Spearman correlation and linear regression tests. ISQ, VBL, and HBL did not differ significantly over time (P ≥ .05). The comparison between the faces showed that only VBL presented significant differences (P ≤ .05) at 1 and 3 years between the following faces: distal and mesial, lingual and mesial, and mesial and buccal. A positive, moderate correlation was observed between ISQ and HBL of the lingual (r = 0.502; P < .01) and mesial (r = 0.536; P < .01) faces at 1 year. The VBL of the mesial face, the HBL of the mesial and lingual faces, and the overall HBL at 1 year were associated with the ISQ values obtained on these faces.

CONCLUSIONS

VBL and HBL remained stable across all implant faces over the 3-year follow-up period. Nevertheless, the lingual face demonstrated the greatest VBL, whereas the mesial face exhibited the highest stability, with minimal VBL observed in the third year. Early bone remodeling, particularly during the first year of MO use, may affect implant stability and appears to be associated with HBL changes on the lingual and mesial faces.