Effect of propolis extract on clinical parameters and salivary level of matrix metalloproteinase 8 in periodontitis patients: A randomized controlled clinical trial.

Background: Periodontitis is the bacterial-induced inflammation of tooth-supporting structures. Local antibacterial agents are used as adjunctive therapy in the treatment of periodontitis. This study aimed to compare the effect of subgingivally delivered propolis extract (a resin produced by honey bees) with chlorhexidine (CHX) mouthwash on clinical parameters and salivary levels of matrix metalloproteinase 8 (MMP-8) in periodontitis patients. Methods: Twenty-eight periodontitis patients in stage II or III and grade B, who had deep periodontal pockets (≥4 mm) around at least three non-adjacent teeth, were divided into two groups. In the control group, patients were prescribed 0.2% CHX mouthwash twice a day for two weeks. In the 20% propolis hydroalcoholic group, subgingival irrigation was performed twice a week for two weeks. Clinical parameters were measured at baseline and after two months. Salivary samples were collected from the propolis and control groups at baseline and two months later to assess MMP-8 levels using the enzyme-linked immunosorbent assay. Additionally, salivary samples from 12 periodontally healthy subjects were used to determine the normal levels of MMP-8. The data were analyzed using SPSS. P<0.05 was considered the level of significance. Results: In the healthy group, the mean salivary levels of MMP-8 were significantly lower than that in the control and propolis groups at baseline (P<0.001). The results indicated a significant improvement in clinical parameters (P<0.001) in the propolis group compared to the control group, while MMP-8 levels decreased significantly in both groups (P<0.001). Conclusion: Propolis is recommended as adjunctive therapy for periodontitis patients. Clinical trials registration code: IRCT2016122030475N3.