Mouthwash as an adjunct – yes or no?

This article explores the current understanding of mechanical cleaning and the use of antiseptic mouthwash and formulations to help with plaque control.

A systematic analysis of the global burden of oral conditions between 1990 and 2010 indicates that 3.9 billion people worldwide were affected by oral conditions. Furthermore, untreated caries in the permanent dentition was the most prevalent condition evaluated for the Global Burden of Disease (GBD) 2010 Study – out of 291 diseases and injuries considered. Meanwhile, severe periodontitis and untreated caries in deciduous teeth were the 6th and 10th most prevalent, respectively.1

Within England, Northern Ireland and Wales, statistics suggest that almost a third of dentate adults have obvious decay in the crowns or roots of their teeth, and two-thirds have visible plaque on at least one tooth. In addition, only 17% of dentate adults have very healthy periodontal tissues and no periodontal disease (i.e. no bleeding, no calculus, no periodontal pocketing of 4mm or more and, in the case of adults aged 55 or above, no loss of periodontal attachment of 4mm or more anywhere in their mouth). Yet the same set of figures suggest that three-quarters of respondents brush their teeth at least twice a day and, of those, a quarter also said they flossed every day.2


All of this is indicative of an unmet need in oral healthcare, but why might that be?

Mechanical cleaning

It is widely accepted that twice-daily brushing and interdental cleaning are essential in helping to control the plaque-mediated conditions of caries and periodontal disease, however there are limitations.3

Barnett (2006) examined a study that considered how effective a powered toothbrush was in reducing plaque and found that, after one and three minutes of brushing, the reduction was 20% and 31%, respectively.4

Additionally, he wrote: ‘[…] surveys conducted in developed countries reveal the percentage of people who claim to use dental floss or some other interdental cleaning device daily to be between 11 and 51 percent, providing additional evidence for a lack of adequate plaque control.’4

In considering how to meet this identifiable need of plaque reduction, Barnett (2006) explored the possibility of using a mouthwash as an adjunct to brushing and interdental cleaning, writing: ‘There is a twofold rationale for daily use of antimicrobial mouthrinses: first, given the inadequacy of mechanical plaque control by the majority of people, as a component added to oral hygiene regimens for the control and prevention of periodontal diseases; second, as a method of delivering antimicrobial agents to mucosal sites throughout the mouth that harbor pathogenic bacteria capable of recolonizing supragingival and subgingival tooth surfaces, thereby providing a complementary mechanism of plaque control.’4

Supporting adjunctive benefits

In 2015, Working Group 2 of the 11th European Workshop in Periodontology agreed that: ‘For the treatment of gingivitis and where improvements in plaque control are required, adjunctive use of antiplaque chemical agents may be considered. In this scenario, mouth rinses may offer greater efficacy but require an additional action to the mechanical oral hygiene regime.’5

Also in 2015, it was suggested that: ‘The adjunctive use of chemical plaque control, together with mechanical control, offers advantages […] in plaque levels control.’6


The group behind this conclusion – Serrano and colleagues (2015) – added: ‘When it comes to the selection of a proper format to deliver the antiseptic agent, the results suggest that mouthrinses may provide better results.’6

Choosing a formulation for plaque control

Boyle and colleagues (2014) conducted a quantitative assessment of data to explore the use of mouthwash in relation to the risk of common oral conditions. Their assessment supports the use of mouthwash in helping to prevent dental plaque.7

More specifically, over a period of less than three months, it was found that a mouthwash containing chlorhexidine was the most effective of the preparations considered, resulting in a reduction of dental plaque. When used for 6 months or longer, however, essential oil mouthwashes equalled or exceeded the effect of chlorhexidine in controlling plaque as an adjunct to standard care.7

A year later, Araujo and colleagues (2015) reported on their meta-analysis, which demonstrated the clinically significant benefit of using an essential oil (EO) mouthrinse as an adjunct to mechanical cleaning over a six-month period.8

They concluded: ‘[The] addition of daily rinsing with an EO mouthrinse to mechanical oral hygiene provided statistically significantly greater odds of having a cleaner […] mouth, which may lead to prevention of disease progression.’8

Three steps to success

Taking into account all of the evidence currently available, it would seem reasonable to suggest that using an appropriately formulated mouthwash as an adjunct to brushing and interdental cleaning may have a beneficial effect on the oral health of some patients […].5



  1. Marcenes W et al. Global burden of oral conditions in 1990-2010: a systematic analysis. Journal of Dental Research 2013; 92(7): 592-597
  2. Adult Dental Health Survey 2009. The Health and Social Care Information Cen
  3. Sharma N et al. Adjunctive benefit of essential oil-containing mouthrinse in reducing plaque and gingivitis in patients who brush and floss regularly: a six-month study. J Am Dent Assoc. 2004; 135: 496-504
  4. Barnett ML. The rationale for the daily use of an antimicrobial mouthrinse. JADA 2006; 137: 16S-21S
  5. Chapple ILC et al. Primary prevention of periodontitis: managing gingivitis. Clin Periodontol 2015; 42 (Suppl. 16): S71-S76
  6. Serrano et al. Efficacy of adjunctive anti-plaque chemical agents in managing gingivitis: a systematic review and meta-analysis. J Clin Periodontol 2015; 42 (Suppl. 16): S106-S138
  7. Boyle P et al. Mouthwash use and the prevention of plaque, gingivitis and caries. Oral Diseases 2014; 20(1): 1-76
  8. Araujo MWB et al. Meta-analysis of the effect of an essential oil-containing mouthrinse on gingivitis and plaque. JADA 2015; 146(8): 610-622