Abstract: Objective: To analyze the association between the methods of oral hygiene instructions(OHI)and the prevalence of peri-implant diseases in patients with periodontitis. Methods: One hundred and twenty-eight patients with 157 implants were included and divided into the chairside personalized OHI group (62 patients, 75 implants) and the traditional OHI group (66 patients, 82 implants) according to the previous OHI methods received. The peri-implant status was defined by clinical examinations,and the patients were investigated by questionnaires for their frequencies of recalls after loading. The frequency of receiving maintenance treatment and the incidence of peri-implant disease were compared between two groups. Results: The proportion of patients who received regular(≤6 months)periodontal and peri-implant maintenance after loading was 74.2%(46/62)in the chairside personalized OHI group,which was significantly higher than 13.6%(9/66)in the traditional OHI group. At the implant level,the number of healthy implants in the chairside personalized OHI group accounted for 73.3%(55/75), which was higher than 13.4%(11/82)in the traditional OHI group. The modified plaque index(mPLI), modified bleeding index (mBI), and peri-implant probing depth(PPD)of implants in the chairside personalized OHI group were significantly lower than those in the traditional OHI group(P<0.001). Conclusion: Chairside personalized OHI by dentists and oral nurses can help patients who had periodontitis and received implant treatment develop good oral hygiene maintenance habit,which is helpful to prevent peri-implant diseases.

Key words: personalized, oral hygiene instruction, periodontitis, peri-implant disease, incidence