This multicenter retrospective study assessed clinical and radiographic outcomes of 686 parallel-walled conical-connection implants consecutively placed in 281 partially and fully edentulous patients. Implants were placed in healed and postextraction sites and subjected to immediate, early, or delayed loading. With a mean follow-up of 10 ± 6.7 months, the implant survival rate was 97.7%, while mean marginal bone loss was 0.7 ± 1.5 mm between implant placement and 1 year (n = 290 implants) and 0.1 ± 0.6 mm between 1 and 2 years (n = 72 implants). Advanced patient age and longer implants were associated with fewer implant failures, while different crestal positions at implant placement were not associated with differences in implant survival or changes in marginal bone level over time.
