Survival and Complication Rates of Narrow-Diameter Implants Used for Immediate Provisional Restoration of the Mandibular Anterior Region: A Retrospective Study

Implant placement in the mandibular anterior region is often limited by narrow alveolar ridge width, particularly in older or medically compromised patients, where bone grafting is contraindicated or undesirable. This area is also crucial for esthetics, necessitating immediate restoration after tooth loss. This retrospective study evaluates the short- and long-term survival and complication rates of narrow-diameter implants (NDIs) placed for immediate provisional restoration in the mandibular anterior region. This study includes 22 one-piece NDIs (Osstem, Korea) placed in 13 patients with narrow ridges, immediately restored with non-functional provisional prostheses. Clinical records and follow-up data throughout 2023 were reviewed. Marginal bone loss (MBL) was assessed using standardized periapical radiographs. A generalized linear mixed model was used to analyze the correlation between MBL and clinical variables. The implant survival rate was 100% (95% CI: 82.7–100) over an average follow-up period of 7 years. Biological and mechanical complication rates were 18.18% and 4.54%, respectively; patient-based complications occurred in 30.77% of cases. No statistically significant predictors of MBL were identified, although smoking showed a trend toward significance (p = 0.096; OR = 8.00; 95% CI: 0.69–92.70). NDIs may be a viable option for immediate provisional restoration in this region, although findings should be interpreted cautiously.