Abstract: Objective To explore the effect of oral irrigator on the periodontal health of the crown bridge prosthesis. Methods Thirty volunteers with crown bridge prosthesis were randomly divided into two groups (n=15). The experimental group used both the oral irrigator and the toothbrush, while the control group used only the toothbrush. Clinical periodontal indices, including plaque index (PLI), gingival index (GI), sulcus bleeding index (SBI) and periodontal pocket sulfide (PS) were examined at two different time points: before treatment and 3 months after treatment. The data of the two groups were statistically analyzed with the SPSS18.0 software package. Results Before treatment, the periodontal indices and PS had no difference between the two groups (P>0.05). After 3 months, PLI, GI, SBI and PS in the experimental group were (1.78±0.50)，(2.25±0.52)，(1.40±0.52), (1.01±0.50) respectively, while PLI, GI, SBI and PS in control group were (2.13±0.70), (2.48±0.48), (1.74±0.64) and(1.58±0.70). All indices in the experimental group were lower than those in the control group (P<0.05). Conclusion The use of oral irrigator can effectively improve the periodontal health of crown bridge prosthesis. Key words： PFM crown bridge; periodontal indices; periodontal pocket sulfide; oral irrigator

Key words: PFM crown bridge, periodontal indices, sulfide in periodontal pocket, oral irrigator