Long-term effectiveness of 6mm micro-rough implants in various indications: A 4.6- to 18.2-year retrospective study.

Abstract

ObjectivesTo evaluate the long‐term effectiveness of 6 mm implants in various indications with a micro‐rough surface after 4.6–18.2 years in function and to assess key factors associated with implant survival, success, and biologic/technical complications.Materials and methodsFifty‐five patients with seventy‐four 6 mm implants placed from 2000 to 2013 attended the re‐examination assessing well‐established clinical and radiographic parameters, biologic and prosthetic complications, and patient‐reported outcome measures.ResultsFive implants were lost after a mean follow‐up period of 9.1 years resulting in a survival rate of 93.2%. All losses occurred in free‐end situations in the mandible. Smoking habit significantly reduced implant survival (hazard ratio 36.25). Two implants exhibited a history of peri‐implantitis, and one implant showed progressive marginal bone loss (MBL) resulting in a success rate of 89.2%. The mean MBL amounted to 0.029 mm. Increased MBL was found for implants placed in the maxilla (0.057 mm) and for implants with a diameter of 4.1 mm (0.043 mm). Soft tissue thickness (1.39 mm) and width of keratinized mucosa (1.91 mm) had no effect on MBL. Patient‐reported outcome measures showed high satisfaction (mean VAS scores 88%) and high quality of life (mean OHIP‐G14 score 2.2).ConclusionThe present study demonstrated survival and success rates of 93.2% and 89.2% for 6 mm implants used in various indications. A factor leading to higher implant failure was smoking, whereas modulating factors increasing annual MBL included implants placed in the maxilla and implants with a diameter of 4.1 mm compared to 4.8 mm.