When should a mouthrinse be recommended?
I think the most appropriate situation is with patients who have gingivitis that is difficult to control and not systemically related. Therapeutic mouthrinses should be used to prevent and treat gingivitis as an adjunct to good oral hygiene and scaling and root planing. Most Americans do not floss everyday. Mouthrinses can’t replace floss but they can help reach areas that are difficult for patients to access. At the same time, if you have patients who already exercise good mechanical plaque control and their gingiva is healthy, they don’t need to use a mouthrinse product. In patients where you are concerned about gingivitis or a malodor problem, then a mouthrinse product can be very effective.
Can using a mouthrinse reach subgingival areas?
Rinsing does not reach deep subgingivally. The literature shows that a vigorous rinsing penetrates about a millimeter to a millimeter and a half subgingivally.1 Gingivitis is caused by plaque just above and below the gingival margin. Mouthrinses are ideal for controlling gingivitis because they reach the margin, the supragingival area, and then a millimeter or so subgingivally.
Are mouthrinses effective on the basement layer of bacteria?
It depends on the mouthrinse. With chlorhexidine, studies show that it penetrates biofilm around 85%-90% in depth.2 Similar studies exist for an essential oils rinse, showing that it also penetrates biofilm similarly to chlorhexidine.3 Triclosan also penetrates biofilm but is available only in dentifrice in the United States, not in mouthrinses. In Europe, triclosan is available in a mouthrinse and dentifrices.
What important advances in mouthrinses have occurred in recent years?
The most important advancement is the inception of the American Dental Association (ADA) Seal of Acceptance program in 1986.4 Since the ADA approval system began, two types of mouthrinses have been approved to treat gingivitis: chlorhexidine and essential oils.
The development of flavors that are more pleasant for the patient and, therefore, improve compliance is another advancement. The introduction of a mouthrinse containing triclosan outside of the United States, which I assume will be available here soon, is also important.
What is the process for a mouthrinse to gain ADA approval as a therapeutic product?
A mouthrinse has to show efficacy with gingivitis and it has to show the product’s mechanism of action, ie, how it reduces gingivitis. If the action is through a reduction of bacteria, then the effect on biofilm must be shown as well. The manufacturer must also demonstrate that the product can penetrate biofilm with two studies, each 6 months in duration, done at two separate investigation centers. In those 6 months, the safety and efficacy of the product must be demonstrated. Microbiologically, the product must also show that it does not have any adverse effects on oral microflora.
How can mouthrinses help with the treatment of periodontal diseases?
Mouthrinses can only help in the treatment of gingivitis. There are no mouthrinses approved for the treatment of periodontitis by the ADA or the Food and Drug Administration.
Some mouthrinses can help xerostomia since their strong flavoring systems may stimulate salivation, provided that some salivary gland tissues are still present. A recent study was conducted in patients with moderate xerostomia that demonstrated an increase in salivary flow, especially with products in the essential oil group. Another interesting finding from this study was that the alcohol in the mouthrinse (21.9%) did not irritate or dry the oral mucosa even though it was used in an exaggerated fashion, ie, three times daily for 4 weeks.5
What is a cosmetic mouthrinse?
A cosmetic mouthrinse only masks the breath and makes the mouth feel better. Also, many breath fresheners and mouthrinses that whiten teeth are cosmetic. For a therapeutic benefit to be assured, I recommend using only ADA accepted products, ie, accepted for the reduction of plaque and gingivitis (not just plaque).
Are nonalcohol-based mouthrinses effective?
The problem with nonalcohol-based mouthrinses is that, so far, none carry the ADA Seal of Acceptance. Also data from 6 month studies related to their efficacy are minimal at this time.
However, alcohol is not needed for efficacy. This was demonstrated in a study done with essential oils.6 The study used three cells. One cell had colored, flavored water, the second cell had the average alcohol content of an essential oil mouthrinse, and the third cell contained essential oils plus alcohol. No significant difference was found between the water group and the alcohol group relative to plaque and gingivitis reduction, therefore demonstrating that the alcohol did not contribute to the therapeutic effect of the product. So alcohol is in these products for two reasons: one is to dissolve the active ingredients of the products and the other is to dissolve the flavoring agents that are used in the products.
Are there indications for recommending nonalcohol-based mouthrinses?
Yes, for example, alcohol-based mouthrinses are not appropriate for patients undergoing chemotherapy who have severe mucositis as well as patients with severe xerostomia. However, in people with moderate xerostomia, alcohol mouthrinses are not a problem as demonstrated in the study by Fischman that I discussed earlier.5 Additionally, alcohol containing mouthrinses are not recommended for use by patients who are trying to break their alcohol habit as well as for those taking medications where alcohol ingestion may cause an upset stomach, ie, metronidazole. For patients where an alcohol-based mouthrinse is contraindicated but who need an antiplaque/antigingivitis agent, I would recommend a product containing triclosan, which is now only available in dentifrice form in the United States, since the evidence for the clinical benefits of nonalcohol containing mouthrinses is not well demonstrated at this time.
- Braun RE, Ciancio, SG. Subgingival delivery by an oral irrigation device. J Periodontol. 1992;63:469-472.
- Netuschil L, Weiger, R, Preisler R, Brecx, M. Plaque bacteria counts and vitality during chlorhexidine, meridol and Listerine mouthrinses. Eur J Oral Sci. 1995;103:355-361.
- Pan P, Barnett ML, Coelho J, Brogdon C, Finnegan MB. Determination of the in situ bactericidal activity of an essential oil mouthrinse using a vital stain method. J Clin Periodontol. 2000;27:256-261.
- Guidelines for acceptance of chemotherapeutic products for the control of supragingival dental plaque and gingivitis. Council on Dental Therapeutics. J Am Dent Assoc. 1986;112:529-532.
- Fischman SL, Aguirre A, Charles, CH. Use of essential oil-containing mouthrinses by xerostomic individuals: determination of potential for oral mucosal irritation. Am J Dent. 2004;17:23-26.
- Lamster IB, Alfano MC, Seiger MC, et al. The effect of Listerine antiseptic on reduction of existing plaque and gingivitis. Clin Prev Dent. 1983;5:12-16.
From Dimensions of Dental Hygiene. Nov 2005;3(11):24-25, 35.