Mouth and teeth: the herbal rinses and the fluoride question

Dental disease is the most common disease in humans and the prevention is mechanical: remove the plaque, and use fluoride.

Fluoride toothpaste has the strongest evidence of anything in this section, reducing cavities by roughly 25% compared to fluoride-free toothpaste. Brushing technique and frequency (twice daily, two minutes) and interdental cleaning matter as much as the product.

Chlorhexidine is the standard antiseptic mouthwash and is effective for gingivitis, with the side effects of staining, taste disturbance and, with long use, some evidence of resistance. It is generally used short-term or for a specific indication.

Herbal mouthwashes — sage, thyme, tea tree, bloodroot-containing products, Aloe, and various essential-oil rinses — have small randomised trials showing reductions in plaque and gingival inflammation, generally inferior to chlorhexidine but often better tolerated. Essential-oil mouthwashes (a specific commercial combination) have reasonable trial evidence for gingivitis. Tea tree oil mouthwash has small trials; it must not be swallowed, and neat tea tree oil is a sensitiser.

A critical warning about bloodroot. Some "natural" toothpastes and mouthwashes sold for gum disease contain Sanguinaria canadensis extract (bloodroot), which is associated with oral leukoplakia — a potentially premalignant white lesion of the mouth. It has been withdrawn or reformulated by some manufacturers for this reason. Do not use a bloodroot-containing oral product.

Xylitol reduces cavities in small trials, in chewing gums and in toothpaste; the effect is real and modest. It is also lethal to dogs, which is a common household poisoning.

Aphthous ulcers (recurrent mouth ulcers) have no reliable cure. Topical corticosteroids, chlorhexidine rinses, and amlexanox are used. Recurrent severe ulcers need assessment — coeliac disease, Crohn's disease, Behçet's disease, B12/folate/iron deficiency and HIV can all present this way.

Halitosis is usually from the tongue and gums, and the treatment is tongue cleaning, treating gum disease, and addressing dry mouth, reflux or sinus problems. A study found that herbal rinses have some effect; the mechanical removal of tongue coating is the mainstay.

A toothache is not a herbal situation. Dental pain means dental pathology, and the treatments are dental. An analgesic buys time until a dentist; a clove oil on the gum does not treat the infection, and a dental abscess that spreads can be life-threatening. A swelling of the face or neck from a dental infection is an emergency.

The studies below use the clinical word caries — in plain English, cavities.