LISTERINE: Commonly asked questions

Is mechanical cleaning enough for all patients?

We know that as dental professionals we can achieve healthy gingiva/periodontium through mechanical cleaning alone. We know it is the gold standard and we will continue to strive to do this. That being said, over the last 11 years of me treating patients both in NHS and private settings, I have been subject to the stark reality that we are fighting a health crisis and not even scraping the tip of the iceberg. I have felt, at times like I am drowning in perio, sighing relief at ‘just gingivitis’ and on the conveyor belt of dentistry.

The daily rigamarole where the term ‘scale and polish’ means more about cosmetic improvement than it does about periodontal health and biofilm management. I have gone home after work, many times exhausted, in a total brain fuzz, defeated and feeling useless. Although, in recent years, the shift has begun and with the use of new communication adjuncts I am able to educate patients more quickly and efficiently I have still found the odd patient has been incredibly difficult to manage and/or inspire. How do I get through to the busy CEO that barely has time or motivation to brush, or the mum of 4 that is low in the pecking order of priorities? Do I just let them continue on a one-way road to periodontitis or can I give them a helping hand?

I do believe on a case-by case basis we can and should be offering additional help. I didn’t realise until recently that the S3 guidelines now offer us an opportunity to introduce chemical adjuncts. They suggest the addition for extra biofilm management and, if our patients are struggling to maintain or achieve health, this should be an option given to them, even for a short-term treatment basis. Mechanical cleaning alone for a number of patients is sufficient to achieve healthy gums but we must be able to help those that are unable to achieve optimal plaque levels with mechanical cleaning alone.

How can mouthwash support in plaque management? 

Mouthwash can act far beyond being just a breath freshener or bactericidal. In fact, mouthwash with a fixed combination of essential oils, like Listerine, has been clinically found, with continuous use, to thin the biofilm. This makes it easier for patients to remove it mechanically, whether that’s with a toothbrush or an interdental aid.

The thinner and easier biofilm is to remove, the less likely it is to become mature and start the inflammatory process. It can be a vicious cycle when a patient comes in with gingivitis and it is uncomfortable to brush sore, bleeding gums or when using interdental aids. It can seem counterintuitive to them and, unfortunately, I do see a lot of patients avoid inflamed areas because of discomfort and bleeding. Inflammation attracts biofilm and biofilm creates inflammation. It’s a two-way process.

By using a clinically proven mouthwash daily, as an adjunct to brushing, we can make it easier for the patient to not only reduce and thin biofilm but to reduce the chance of inflammation coming back once stable. Once stable, it becomes easier and more comfortable for the patient to manage. Mouthwash is never a replacement for interdentals and mechanical cleaning, it is used as an adjunct to achieve better plaque management.

Patients are humans and they are not perfect. They have busy lives, different priorities, they have different behaviour types and respond differently to advice and diagnosis. I always want to ensure I take this into account and see them as a person and not just a walking mouth. This is why I believe mouthwash can be a great tool for a select number of patients.

Won't daily use mouthwash wash away toothpaste fluoride? 

It’s a common misconception that mouth rinse washes away fluoride. Fluoride levels are measured as the fluoride reserve available within saliva after a fluoride event (toothpaste, rinsing, etc.). Initial high levels of fluoride are cleared from the mouth after 30 minutes, with around 100-200ppm being held in the pellicle acting as a reservoir. There is robust evidence to support this.

Research by Duckworth confirms that if a mouthwash with a fluoride level of at least 100ppm is used post brushing, there is no impact on the salivary fluoride reserves versus toothpaste. If a mouthwash containing 200ppm of fluoride is used, the residual salivary fluoride levels will be double that left behind after retention of the toothpaste slurry alone. The fluoride levels of toothpaste and mouthwash cannot be compared as fluoride’s bioavailability is different in toothpaste and mouthwash. It’s important to also mention, if a mouthwash containing fluoride also contains a plaque management active ingredient, the patient will benefit from the adjunctive effect of bacterial kill and increased regeneration time, therefore strengthening enamel with the fluoride content and helping to thin the biofilm with the antiplaque active ingredient.

Obviously, if someone is high caries risk, then I would encourage spit don’t rinse with water, and the use of a mouth rinse containing fluoride at a different time of the day. However, if they would benefit from better plaque management, I would recommend an essential oil-containing rinse with at least 100 ppm of fluoride immediately after brushing.

What difference has recommending a daily use mouthwash made to your patients?

With the latest BSP guidelines it’s now a documented, evidence based S3 suggestion to use chemotherapeutics in patients who are in step 4. We are wanting to minimise the risk of these patients moving from stable to unstable periodontal disease. Obviously, home care is a massive factor in achieving this, so it just makes sense to me to have something I can comfortably recommend with additional benefits.

We’ve all got those patients who have a little bit of bleeding present, it’s not ‘just’ gingivitis. It’s the beginning of disease. We need to address it to shift the paradigm. Now I don’t recommend it to all of my patients. I generally focus on patients with complex restorations, gingivitis or those in step 4. The ones I do recommend it to have been surprised by the long-term effects it has had on their oral health. Generally, there is less inflammation and biofilm, especially in those patients who are more susceptible to periodontal disease.

I can show them the reduction in bleeding and plaque scores, it has become such a great motivator for patients. Mouth rinse with essential oils slows down the bacterial production rate and provides an opportunity for that patient to manage their own biofilm at home, which I think is really important. Often, dental professionals worry about patients replacing homecare with mouth rinse, but I always tell the patient it’s not a replacement but it’s providing you with a head start. I personally use an essential oil mouth rinse post brushing twice a day and my mouth has never felt cleaner.

What does the latest evidence tell us about daily use mouthwash for plaque management?

Contrary to traditional paradigms, the latest evidence tells us that daily mouthwash use, as an adjunct to mechanical plaque control, and I emphasise an adjunct and not a replacement for it, does provide significant additional reductions in plaque scores and indeed gingival redness and bleeding scores.

The data came from a 2015 systematic review by Serrano and colleagues, which was a technical review for the Prevention workshop held by the EFP, which concluded that chemical agents in toothpaste and mouthwash do offer adjunctive benefit when used daily. This data was further supported in 2020 by another systematic review by Figuero and colleagues who showed the same thing in an updated systematic review and meta-analysis undertaken for the 1st ever S3-level Clinical Guideline in dentistry.

The Figuero study actually ranked chemical agents in toothpastes and mouth rinses in terms of their effect size on gingival index, % bleeding sites and plaque index. The data for each is displayed in tables 2, 3 and 4 of that paper and is worth a look. TABLE 4 documents the plaque index data and it showed that Essential Oils, CXD 0.2% (not 0.12%), CPC (high and low concentrations) and AmF_SnF (amine Fl/Stannous Fl) all produced significant additional reductions in plaque scores in that respective order of performance.

Importantly, the tables also enumerate the number of studies that the data was derived from, which varies from one to ten, clearly the larger the number of studies the more reproducible the result is. It is important however to consider each patient as an individual and not to generalise when it comes to use of chemical adjuncts, and so decisions should always be made on a case by case basis.

So, in summary, the evidence base has developed and care pathways change with time, we can no longer afford to ignore the evidence base for certain mouth rinses as adjuncts to mechanical plaque control.

Can you explain what “spit don’t rinse” means?

The “spit don’t rinse” guidance is important guidance, but with time has become generalised and jingoistic, ultimately resulting in misinterpretations, which are not in our patients’ best interests. It refers to retaining Fluoride from the toothpaste slurry, especially in children and those at high risk of caries.

Rinsing the mouth with water after brushing was a traditional habit...even a protocol, but of course the water dilutes the fluoride reservoir in saliva and is therefore counter-productive. Therefore, the evidence base supports a message of “spit don’t rinse with water” and not a general instruction of “spit don’t rinse” – the devil is always in the detail!!

It does not make sense if the post-brushing rinse is with a fluoride-containing mouthwash. The latter, provided the mouthwash has a minimum 100ppm fluoride, does not appear to have an impact on that salivary fluoride reservoir, relative to not rinsing at all. This was shown many years ago by Duckworth and colleagues, and so provided the mouth rinse used has 100ppm fluoride as a minimum, it has the same effect as 1450ppm fluoride toothpastes.

The fluoride retained in the plaque pellicle following toothbrushing is about 100-200ppm, and it is that reservoir that is important for ensuring that the enamel surface has sufficient fluoride protection. If such mouth rinses also have antimicrobial properties, then there may be benefit in rinsing with them post-brushing in certain patients.

The exception is under 7-year-olds who have not yet developed a controlled swallowing reflex, and who therefore may not be able to use mouth rinse without swallowing it. In those over 7 years and who can control their swallowing reflex, then a fluoride rinse post-brushing may offer additional benefit.

Full interview with Iain, Ben and Laura