Inclusion Criteria:  To be included in the original trials, patients had to be at least 18 years old.  Exclusion Criteria:  Exclusion criteria were an inability to follow investigational procedures, any factor at the discretion of the investigator that was considered to contraindicate participation, and any disease or treatment known to compromise the bone quality at the implant site. For patients who had lost or removed the implant, the time to implant loss was recorded. Patients who could not attend the 5 or 10 year follow-up visit for other reasons were included in the implant survival analysis as well; the last available information regarding implant survival was obtained verbally from the patient, from medical records, or from information captured from the original investigations. Furthermore, patients were excluded if they had a bone thickness less than 4 mm at the implant site during implantation.