Abstract: ［Abstract］ Objective To explore the clinical efficacy on Kangfuxin liquid combined with Minocycline in treatment of chronic periodontitis and its effect on expression of programmed death-1（PD-1） and programmed death-ligand 1（PD-L1）.
Methods One hundred and ninety-two patients with periodontitis were randomly divided into two groups, 96 cases in each group. the observation group was treated with Minocycline combined with Kangxinxin liquid, the control group was treated with Minocycline. The clinical efficacy and total effective rate of the two groups were observed. The plaque, periodontal probing depth and gingival bleeding index of the two groups were compared. The changes of serum inflammatory factors before and after treatment were compared. The serum PD-1 and PD-L1, level changes and adverse reactions before and after treatment were compared.
Results The clinical efficacy and total effective rate of the observation group were higher than those of the control group(P＜0.05). The plaque index, periodontal probing depth and gingival bleeding index of the observation group were lower than the control group(P＜0.05). After treatment, the serum levels of interferon-γ（IFN-γ）, tumor necrosis factor-α（TNF-α）, interleukin-8（IL-8） and hypersensitive C-reactive protein（hs-CRP） were significantly lower than those before treatment(P＜0.05), and IL-10 was significantly higher than that before treatment(P＜0.05). The observation group decreased and increased greatly. The serum levels of IFN-γ, TNF-α, IL-8 and hs-CRP in the observation group were lower than those in the control group(P＜0.05). There was no significant difference in the incidence of adverse reactions between two groups(P＞0.05).
Conclusion Minocycline combined with Kangxinxin can effectively reduce the expression of PD-1 and PD-L1 on CD4+ and CD8+ T lymphocytes in patients with chronic periodontitis, relieve inflammation, improve clinical symptoms, and improve treatment efficacy.

Key words: periodontitis； minocycline, Kangfuxin liquid