The study sample will consist of participants from the 2010-cohort, who were selected according to the following eligibility criteria:  Inclusion Criteria:  need for single implants in the posterior region of the maxilla and mandible; indication of 6-mm implants according to preoperative evaluation  Exclusion Criteria:  previous problems with osseointegration failure in the region of interest; bone graft or use of biomaterials; diabetes; heavy tobacco use (over 10 cigarettes per day); immunosuppression; local radiation therapy; poor oral hygiene; active periodontal disease in the remaining teeth; cystic or neoplastic lesions; removable dentures in the opposing arch.