RESUMEN
Objective To analyse the influencing factor,clinical appearance and solution of peri-implanti-tis,especially caused by cement remnant. Methods In this retrospective study 23 typical cases of peri-implantitis were collected in our implantology center from Jan.2016 to Dec.2016.The general data such as age,sex,systemic diseases,habits of smoking and alcohol,history of periodontitis,surgery process,materials and way of restoration were recorded in details.This study enrolled individuals from a private practice who had cement-retained implant res-torations,scheduled for regular implant maintenance or coming for consultation on a complication. Results All screw-retention(100%)and 50% cement retention peri-implantitis cases suffered from local and systemic diseases, 30% screw-retention and 20% cement retention healthy cases suffered from local and systemic diseases,which showed a significant differences(P<0.05),but there was no significant difference between screw and cement reten-tion in peri-implantitis group.85.7% of screw-retention and 50% of cement retention cases had a poor oral hygiene (PLI=2or3).Despite the other possible factors(such as diabetes,periodontitis and heavy smoker),8 cement-re-tained implants suffered from peri-implantitis.5 cases showed the cement remnant on the x-ray photo. Conclusion There are many pathogenic factors leading to peri-implantitis that may be single or combined.Cement remnant direct-ly leads to peri-implantitis.Clearance of excess cement together with scaling and laser treatment,or even combined with guided bone regeneration surgery are effective for treatment of peri-implantitis.