Tooth Paste

Tooth Paste

Toothpaste is a paste or gel dentifrice used with a toothbrush to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it is an abrasive that aids in removing dental plaque and food from the teeth, assists in suppressing halitosis, and delivers active ingredients (most commonly fluoride) to help prevent tooth decay (dental caries) and gum disease (gingivitis).[1] Owing to differences in composition and fluoride content, not all toothpastes are equally effective in maintaining oral health. The decline of tooth decay during the 20th century has been attributed to the introduction and regular use of fluoride-containing toothpastes worldwide.[2][3] Large amounts of swallowed toothpaste can be toxic.[4]

Usefulness[edit]

Toothpastes are generally useful to maintain dental health. Toothpastes containing fluoride are effective at preventing tooth decay.[2][5][6] Toothpastes may also help to control and remove plaque build-up, promoting healthy gums. A 2016 systematic review indicated that using toothpaste when brushing the teeth does not necessarily impact the level of plaque removal.[7] However, the active ingredients in toothpastes are able to prevent dental diseases with regular use.[8]

Ingredients[edit]

Toothpastes are derived from a variety of components, the three main ones being abrasives, fluoride, and detergent.

Abrasives[edit]

Abrasives constitute 8-20% of a typical toothpaste.[8] These insoluble particles are designed to help remove plaque from the teeth.[9] The removal of plaque inhibits the accumulation of tartar (calculus) helping to minimize the risk of gum disease.[10] Representative abrasives include particles of aluminum hydroxide (Al(OH)3), calcium carbonate (CaCO3), sodium bicarbonate, various calcium hydrogen phosphates, various silicas and zeolites, and hydroxyapatite (Ca5(PO4)3OH).

Abrasives, like the dental polishing agents used in dentists’ offices, also cause a small amount of enamel erosion which is termed “polishing” action. Some brands contain powdered white mica, which acts as a mild abrasive, and also adds a cosmetically pleasing glittery shimmer to the paste. The polishing of teeth removes stains from tooth surfaces, but has not been shown to improve dental health over and above the effects of the removal of plaque and calculus.[11]

The abrasive effect of toothpaste is indicated by its RDA value. Toothpastes with RDA values above 250 are potentially damaging to the surfaces of teeth. The American National Standards Institute and American Dental Association considers toothpastes with an RDA below 250 to be safe and effective for a lifetime of use.[12]

Fluorides[edit]

Fluoride in various forms is the most popular and effective active ingredient in toothpaste to prevent cavities.[9] Fluoride is present in small amounts in plants, animals, and some natural water sources. The additional fluoride in toothpaste has beneficial effects on the formation of dental enamel and bones. Sodium fluoride (NaF) is the most common source of fluoride, but stannous fluoride (SnF2), and sodium monofluorophosphate (Na2PO3F) are also used.[9] At similar fluoride concentrations, toothpastes containing stannous fluoride have been shown to be more effective than toothpastes containing sodium fluoride for reducing the incidence of dental caries and dental erosion,[13][14][15][16][17] as well as reducing gingivitis.[18][19][20][21][22] Some stannous fluoride-containing toothpastes also contain ingredients that allow for better stain and calculus removal.[23] A systematic review revealed stabilised stannous fluoride-containing toothpastes had a positive effect on the reduction of plaque, gingivitis and staining, with a significant reduction in calculus and halitosis compared to other toothpastes.[24] Furthermore, numerous clinical trials have shown gluconate chelated stannous fluoride toothpastes possess superior protection against dental erosion and dentine hypersensitivity compared to other fluoride-containing and fluoride-free toothpastes.[25]

Much of the toothpaste sold in the United States has 1,000 to 1,100 parts per million fluoride. In European countries, such as the UK or Greece, the fluoride content is often higher; a sodium fluoride content of 0.312% w/w (1,450 ppm fluoride) or stannous fluoride content of 0.454% w/w (1,100 ppm fluoride) is common. All of these concentrations are likely to prevent tooth decay, according to a 2019 Cochrane review.[6] Concentrations below 1,000 ppm are not likely to be preventive, and the preventive effect increases with concentration.[6] Clinical trials support the use of high fluoride (5,000 ppm fluoride) dentifrices, for prevention of root caries in elderly adults by reducing the amount of plaque accumulated, decreasing the number of mutans streptococci and lactobacilli and possibly promoting calcium fluoride deposits to a higher degree than after the use of traditional fluoride containing dentifrices.[6]

Surfactants[edit]

Many, although not all, toothpastes contain sodium lauryl sulfate (SLS) or related surfactants (detergents). SLS is found in many other personal care products as well, such as shampoo, and is mainly a foaming agent, which enables uniform distribution of toothpaste, improving its cleansing power.[11]

Other components[edit]

Antibacterial agents[edit]

Triclosan, an antibacterial agent, is a common toothpaste ingredient in the United Kingdom. Triclosan or zinc chloride prevent gingivitis and, according to the American Dental Association, helps reduce tartar and bad breath.[1][26] A 2006 review of clinical research concluded there was evidence for the effectiveness of 0.30% triclosan in reducing plaque and gingivitis.[27] Another Cochrane review in 2013 has found that triclosan achieved a 22% reduction in plaque, and in gingivitis, a 48% reduction in bleeding gums. However, there was insufficient evidence to show a difference in fighting periodontitis and there was no evidence either of any harmful effects associated with the use of triclosan toothpastes for more than 3 years. The evidence relating to plaque and gingivitis was considered to be of moderate quality while for periodontitis was low quality.[28] Recently, triclosan has been removed as an ingredient from well-known toothpaste formulations. This may be attributed to concerns about adverse effects associated with triclosan exposure. Triclosan use in cosmetics has been positively correlated with triclosan levels in human tissues, plasma and breast milk, and is considered to have potential neurotoxic effects.[29] Long-term studies are needed to substantiate these concerns.

Chlorhexidine is another antimicrobial agent used in toothpastes, however it is more commonly added in mouthwash products.[30] Sodium laureth sulfate, a foaming agent, is a common toothpaste ingredient that also possesses some antimicrobial activities.[31] There are also many commercial products available in the market containing different essential oils, herbal ingredients (e.g. chamomile, neem, chitosan, Aloe vera), and natural or plant extracts (e.g. hinokitiol).[32][33] These ingredients are claimed by the manufacturers to fight plaque, bad breath and prevent gum disease. A 2020 systematic metareview found that herbal toothpastes are as effective as non-herbal toothpastes in reducing dental plaque at shorter period of follow-up (4 weeks).[34] However, this evidence comes from low-quality studies.