Abstract: PURPOSE: To explore the value of metronidazole combined with minocycline in reducing infection after dental implant in patients with localized periodontitis. METHODS: A total of 120 patients with localized periodontitis who underwent dental implantation in the Department of Stomatological, Shanghai Pudong New Area People's Hospital from August 2021 to September 2022 were selected. According to the way of postoperative infection prevention, the patients were divided into control group and experimental group, with 60 patients in each group. The control group was orally given roxithromycin capsules, and the experimental group was locally coated with minocycline hydrochloride ointment and metronidazole gel. The incidence of postoperative infection and complications was compared between the two groups. The modified gingival creval bleeding index (mSBI), periodontal probing depth (PD) and modified plaque index (mPLI) of the patients were examined by periodontal probe. Serum C-reactive protein (CRP) level was determined by immunoturbidimetry and tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) level was determined by ELISA. SPSS 25.0 software package was used for statistical analysis of the data. RESULTS: Good healing rate of the experimental group was 91.67% higher than that of the control group 73.33%, postoperative infection rate was 8.33% and complication rate was 6.67% in the experimental group, significantly lower than that of the control group (26.67% and 20.00%), respectively (P<0.05). After treatment, the level of CRP, TNF-α and IL-6 in the experimental group were significantly lower than those in the control group (P<0.05). At 3 and 6 months after treatment, mSBI, mPLI and PD in the experimental group were significantly lower than those in the control group(P<0.05). CONCLUSIONS: The administration of minocycline hydrochloride and metronidazole in patients with localized periodontitis undergoing implantation can reduce oral inflammatory response, reduce postoperative infection and other complications, and improve periodontal health.

Key words: Localized periodontitis, Metronidazole, Minocycline, Infection, Inflammatory factor