The long-term effect of a zinc acetate and chlorhexidine diacetate containing mouth rinse on intra-oral halitosis-A randomized clinical trial

J Clin Periodontol. 2017 Oct;44(10):1010-1019. doi: 10.1111/jcpe.12779. Epub 2017 Aug 30.


Aim: To evaluate the long-term effects of a zinc acetate and chlorhexidine diacetate mouth rinse (Zn/CHX) on intra-oral halitosis.

Materials and methods: Forty-six adults with intra-oral halitosis were randomized into a 6-month, double-blind, placebo-controlled clinical study. The presence of intra-oral halitosis was evaluated at baseline, 3 and 6 months after treatment by assessment of organoleptic score (OLS) and by total volatile sulphur compounds (T-VSC), hydrogen sulphide (H2 S) and methyl mercaptan (MM) concentrations in exhaled air.

Results: A Zn/CHX mouth rinse provided significantly better control of intra-oral halitosis than a placebo mouth rinse. At 3 and 6 months, individuals rinsing with the Zn/CHX rinse presented with reductions of the OLS, T-VSC (p < .01, respectively), H2 S (p < .001), and MM (p < .01) in subjects' exhaled air. At 6 months, 68.2% of individuals using the Zn/CHX rinse experienced a 1 or 2 category improvement in OLS compared with 19.1% of placebo-treated subjects. 91% of subjects in the Zn/CHX group were categorized as being effectively treated for intra-oral halitosis (i.e. H2 S < 112 ppb), compared to 43% in the placebo group.

Conclusion: Zn/CHX mouth rinse provides effective long-term efficacy against intra-oral halitosis, assessed both objectively and subjectively. With regular rinsing, the effect was sustained for 6 months.

Keywords: Zn/CHX rinse; bad breath; halitosis; hydrogen sulphide; mouth rinse; volatile sulphur compounds.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Anti-Infective Agents, Local / therapeutic use*
  • Chlorhexidine / therapeutic use*
  • Double-Blind Method
  • Female
  • Halitosis / drug therapy*
  • Humans
  • Male
  • Middle Aged
  • Mouthwashes / therapeutic use*
  • Sulfur Compounds / analysis
  • Treatment Outcome
  • Zinc Acetate / therapeutic use*


  • Anti-Infective Agents, Local
  • Mouthwashes
  • Sulfur Compounds
  • Zinc Acetate
  • Chlorhexidine