Clinical and radiographic evaluation of early loaded narrow-diameter implants : 5-year follow-up of a multicenter prospective clinical study

Objective: This study was initiated to evaluate the 5-year implant survival rate and marginal bone levels around a 3.0-mm implant when replacing a single tooth in the anterior region. Materials and methods: The study was designed as a prospective, single-arm, multicenter clinical study. Patients missing 12, 22, 32, 31, 41 or 42 teeth were included, and implants of 3.0 mm diameter and different lengths were placed by a one-stage surgery protocol. Definitive cemented crowns were placed 6–10 weeks later. Clinical and radiographic measurements were taken at implant installation, at loading and at the 6-, 12-, 24-, 36-, 48- and 60-month follow-up visits. Results: Sixty-nine patients with 97 implants were included in this study. Four implants were lost before loading (4.12% failure rate). Implant marginal bone levels did not differ statistically after the 1-year follow-up visit. After 5 years, no bone loss was observed for 50.60% of the implants and only 8.43% of them lost more than 1 mm. Similarly, probing pocket depths and gingival zenith scores did not change significantly. Conclusions: The use of the two-piece narrow 3.0-mm titanium dental implant for the restoration of upper lateral or lower incisors is safe and results in stable marginal bone levels and probing pocket depths after 5 years of function.