Objective:To evaluate the clinical outcomes of implant-retained overdentures.Methods:57 patients treated by implant-retained overdentures were included.Parameters for peri-implant tissue conditions (e.g.peri-implant probing depth,plaque index,bleeding on probing,mucosal hyperplasia,peri-implant marginal bone loss) and prosthetic complications were examined and recorded.The precentage of satisfaction of the patients was assessed using the visual analog scale (VAS).Results:After an average follow-up of (48±11.3) months,the survival rate of the implants was 98.1%,the marginal bone loss was (1.38±0.74) mm.There was no statistically difference among the different attachment groups(bar,magnet and ball) regarding the peri-implant marginal bone loss or bleeding on probing(P>0.05).The peri-implant probing depth and plaque index in patients with magnet and ball attachments were lower than those in patients with bar attachments(P<0.05).The major complications were the upper abutment fracture,prostheses fracture and screw loosening.Most patients were satisfied with their prostheses and there was no statistically significant difference between the attachment types(P>0.05),except that magnet and ball attachments were much easier to clean compared with bar attachments(P<0.05).Conclusion:Implant-retained overdenture is a successful and satisfactory treatment option for patients with edentulous jaw.The patients should been given regular clinical examinations to keep peri-implant tissue health and reduce the complications,especially those with bar attachments.