Propolis is a resinous mixture that honey bees collect from tree buds, sap flows, or other botanical sources. It has a long tradition of medical use in many parts of the world and is thought to have several beneficial health properties. The use of propolis mouthrinse or gel as a supplementary intervention for oral health has increased during the last decade in Taiwan, especially for oncology, hospice, and long-term care settings. However, the effect of propolis on oral health is not well understood.
The objective of this systematic review was to present the best available evidence regarding the effects of propolis use on oral health, including oral infection, dental plaque and stomatitis.
Types of participants
The review considered all studies that included propolis use in humans, in any setting except for oncology patients.
Types of intervention(s)
The included studies focused on the effects of propolis on oral health. Interventions included propolis mouthrinse, gel, or capsule. Comparators were placebo, usual care, or other mouth rinse.
Types of studies
Randomized controlled trials and clinical trials of propolis therapy were included in the review.
Types of outcomes
The outcomes that were considered for inclusion were the effects of propolis on oral infection, dental plaque and stomatitis.
Reviewers conducted a systematic search for relevant articles published in English or Chinese between 1969 and 2012 that were indexed in the following databases: Cochrane Database of Systematic Reviews, CINAHL, PubMed, Science Direct, Conference Proceedings, Oral Health Journal Index, and Chinese Electronic Periodical Services.
Two reviewers independently assessed methodological quality of studies using standardized critical appraisal instruments from the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument.
Quantitative data was extracted using the standardized data extraction tool from the Joanna Briggs Institute.
Where possible, data was pooled in a meta-analysis. For studies where methodological heterogeneity was present, findings were presented in narrative form.
Nine trials were included in the review, but only eight trials published from 1997-2011 with a total of 194 participants had extractable data. The result of the meta-analysis indicated that propolis had an effect on reducing dental plaque, but it was not statistically significant. The results were not statistically significant for oral infection or stomatitis. No harmful effects were identified on the outcome measures reported.
Whilst eight suitable randomized controlled trials and clinical trials investigating propolis therapy for oral health were extracted, several were small studies, or were of poor quality. Although there are a number of promising indications, in view of the limited number and quality of studies, and the variation in results between studies, this review highlights the need for further well designed trials so that more robust conclusions may be drawn.
Implications for practice
Due to the small sample sizes of included studies and significant heterogeneity across studies, specific recommendations for practice regarding use of propolis for oral health cannot be made.
Implications for research
In order to draw definitive conclusions regarding the effectiveness of propolis for oral care, more randomized controlled trials are needed.