Inclusion Criteria:  Males or females with, at least 18 years old. Single and multiple gaps (premolars & molars) that require single and partial fixed restorations (2 implants, 1 pontic). Adequate bone quantity at the implant site to allow the placement of diameter 3.5, 3.75 or 4.5 mm and lengths of 6 mm, 8 mm, 10 mm, 12 mm or 14 mm. Patients had to be informed of the follow up visits and willing to attend to the clinical centre for these appointments.  Exclusion Criteria:  As systemic exclusion criteria, patients with systemic diseases that could interfere with dental implant therapy, smokers of more than 10 cigarettes per day, alcoholism or drug abuse, physical or mental disabilities, pregnant or lactating women and/or conditions or circumstances, in the opinion of the investigator, that could prevent the completion of the participation in the study or interfering with the analysis of study results (non-compliance).  The presence of one of the following circumstances was considered a local exclusion criterion: patients with inadequate oral hygiene (plaque control > 25%) (Mombelli et al., 1987), untreated endodontic lesions, any bone augmentation procedure before or during the implant placement, local inflammation (including untreated periodontitis), mucosal diseases such as erosive lichen planus, history of local irradiation therapy in the head-neck area and/or extraction sockets with less than 12 weeks of healing.