Toothpaste

Toothpaste from a tube being applied to a toothbrush

Toothpaste is a paste or gel dentifrice used with a toothbrush as an accessory to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it acts as an abrasive that aids in removing the dental plaque and food from the teeth, assists in the elimination and/or masking of halitosis, and delivers active ingredients such as fluoride or xylitol to help prevent tooth and gum disease (gingivitis). It is important to note that most of the cleaning is done by the mechanical use of the toothbrush, and not by the toothpaste.[1] Most toothpastes contain trace amounts of chemicals that may be toxic when ingested; toothpaste is not intended to be swallowed.

Contents

History

Early toothpastes

The earliest known reference to toothpaste is in a manuscript from Egypt in the 4th century A.D., which prescribes a mixture of iris flowers. However, toothpastes or powders did not come into general use until the 19th century. The Greeks, and then the Romans, improved the recipes for toothpaste by adding abrasives such as crushed bones and oyster shells.[2] In the 9th century, the Persian musician and fashion designer Ziryab is known to have invented a type of toothpaste, which he popularized throughout Islamic Spain.[3] The exact ingredients of this toothpaste are currently unknown,[4] but it was reported to have been both "functional and pleasant to taste".[3] It is not known whether these early toothpastes were used alone, were to be rubbed onto the teeth with rags, or were to be used with early toothbrushes such as neem tree twigs or miswak.

Tooth powder

Tooth powders for use with toothbrushes came into general use in the 19th century in Britain. Most were homemade, with chalk, pulverized brick, or salt as ingredients. An 1866 Home Encyclopedia recommended pulverized charcoal, and cautioned that many patented tooth powders that were commercially marketed did more harm than good.

Modern toothpastes

Modern toothpaste gel

An 18th century American and British toothpaste recipe containing burnt bread has been found. Another formula around this time called for dragon's blood (a resin), cinnamon, and burnt alum.[5]

By 1900, a paste made of hydrogen peroxide and baking soda was recommended for use with toothbrushes. Pre-mixed toothpastes were first marketed in the 19th century, but did not surpass the popularity of tooth-powder until World War I. In 1892, Dr. Washington Sheffield of New London, Connecticut, manufactured toothpaste into a collapsible tube. Sheffield's toothpaste was called Dr. Sheffield's Creme Dentifrice. He had the idea after his son traveled to Paris and saw painters using paint from tubes. In New York City in 1896, Colgate & Company Dental Cream was packaged in collapsible tubes imitating Sheffield.

Fluoride was first added to toothpastes in 1914, and was criticized by the American Dental Association (ADA) in 1937. Fluoride toothpastes developed in the 1950s received the ADA's approval. To develop the first ADA-approved fluoride toothpaste, Procter & Gamble started a research program in the early 1940s. In 1950, Procter & Gamble developed a joint research project team headed by Dr. Joseph Muhler at Indiana University to study new toothpaste with fluoride. In 1955, Procter & Gamble's Crest launched its first clinically proven fluoride toothpaste. On August 1, 1960, the ADA reported that "Crest has been shown to be an effective anticavity (decay preventative) dentifrice that can be of significant value when used in a conscientiously applied program of oral hygiene and regular professional care." Countries limit and suggest different amounts of fluoride acceptable for health.

In 2006 appeared in Europe the first toothpaste containing biomimetic synthetic hydroxylapatite as an effective alternative to fluoride for the remineralization and reparation of tooth enamel. The function of the biomimetic hydroxylapatite is to protect the teeth by creating a new layer of synthetic enamel around the tooth instead of hardening the existing layer with fluoride that chemically changes it into Fluorapatite.

In June, 2007, the US Food and Drug Administration and similar agencies in Panama, Puerto Rico and Australia advised consumers to avoid certain brands of toothpaste manufactured in China, after some were found to contain the poisonous diethylene glycol, also called diglycol or labeled as "DEG" on the tube. The chemical is used in antifreeze as a solvent and is potentially fatal.[6]

Ingredients and flavors

Active ingredients

Fluoride in various forms is the most popular active ingredient in toothpaste to prevent cavities. Although it occurs in small amounts in plants, animals, and some natural water sources, and has effects on the formation of dental enamel and bones, it is not considered to be a dietary essential and no deficiency signs are known. Sodium fluoride (NaF) is the most common form; some brands use sodium monofluorophosphate (Na2PO3F) or olaflur. Much of the toothpaste sold in the United States has 1000 to 1100 parts per million fluoride ion from one of these active ingredients, in the UK the fluoride content is often higher, a NaF of 0.32% w/w (1,450 ppm fluoride) is not uncommon. This consistency leads some to conclude that cheap toothpaste is just as good as expensive toothpaste. When the magazine Consumer Reports rated toothpastes in 1998, 30 of the 38 were judged excellent. Application of fluoride also prevents moisture build-up in some surfaces. Other ingredients are less commonly used, including Hydroxyapatite nanocrystals and calcium phosphate for remineralization,[7] and strontium chloride or potassium nitrate to reduce sensitivity.

Triclosan, an antibacterial agent, is an active ingredient in some toothpastes, used to prevent gingivitis.[8][9] Triclosan is a common toothpaste ingredient in the UK.

Other ingredients

Toothpaste is sold in many brands

In addition to fluoride, the other fundamental ingredient in most toothpastes is an abrasive. Studies have shown that abrasives in toothpaste reduce the time needed to remove plaque from the teeth by approximately 50%. Abrasives, like the dental polishing agents used in dentist's 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. Many may contain frustules of dead diatoms as a mild abrasive. The removal of plaque and calculus prevents caries and periodontal disease. 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.

Many, though not all, toothpastes contain sodium lauryl sulfate (SLS) or another of the sulfate family. SLS is found in other personal care products as well, such as shampoo, and is largely a foaming agent although it also acts as a powerful antimicrobial. Due to the anionic charge of SLS, mouthwashes containing cetylpyridinium chloride (which has a cationic charge and thus neutralises SLS) should not be used straight after brushing. SLS may cause a greater frequency of mouth ulcers in some people as it can dry out the protective layer of oral tissues causing the underlying tissues to become damaged.[10]

Ingredients such as baking soda, enzymes, vitamins, herbs, calcium, calcium sodium phosphosilicate, mouthwash, and/or hydrogen peroxide are often combined into base mixes and marketed as being beneficial. Toothpaste is formulated as to dissolve in the alkaline pH of human saliva. Some manufacturers add antibacterial agents, for example triclosan[8] or zinc chloride, to prevent gingivitis. According to the American Dental Association, triclosan also helps reduce tartar and bad breath.[8] Bases such as sodium hydroxide are also used to neutralize acids.

Toothpaste comes in a variety of colorings, and flavors. The more usual flavorings are some variation on mint (spearmint, peppermint, regular mint, etc.). Other more exotic flavors include: anise, apricot, bubblegum, cinnamon, fennel, lavender, neem, ginger, vanilla, lemon, orange, pine. More unusual are flavors include peanut butter, iced tea, and even whisky. Unflavored toothpaste does exist, however, most are flavored and sweetened. Because sugar promotes growth of bacteria that cause tooth decay, artificial sweeteners such as sorbitol or saccharin are generally used instead. The inclusion of sweet-tasting but toxic diethylene glycol in Chinese-made toothpaste led to a multi-nation and multi-brand toothpaste recall in 2007.

Critics

Toxicity

With the exception of toothpaste intended to be used on pets such as dogs and cats, and toothpaste used by astronauts, most toothpaste is not intended to be swallowed, and doing so may cause nausea or diarrhea; fluoride toothpaste can be either acutely toxic if swallowed in large amounts, or chronically toxic if swallowed in any amount consistently. If a large amount of toothpaste is swallowed at once, Poison Control should be contacted immediately.[11] Extended consumption of large volumes of fluoride toothpaste can result in fluorosis. Though the main reason why the NHS advises supervised brushing up to 6 years is to ensure proper brushing, keeping an eye on toothpaste consumption, and thus the risk of fluorosis.[12] It is worthy of note that the risk of using fluoride is low enough that the use of 'full-strength' toothpaste (1350-1500ppm fluoride) is advised for all ages (though smaller volumes are used for young children; a 'smear' of toothpaste until 3 years).[12] There are several non-fluoride toothpaste options available in the market for those who choose not to use fluoride. Natural toothpaste can contain peppermint oil, myrrh, plant extract(strawberry extract), special oils and cleansing agents. Case reports of plasma cell gingivitis have been reported with the use of herbal toothpaste containing cinnamon.[13]

Striped toothpaste

The red area represents the material used for stripes, and the rest is the main toothpaste material. The two materials are not in separate compartments; they are sufficiently viscous that they will not mix. Applying pressure to the tube causes the main material to issue out through the pipe. Simultaneously, some of the pressure is forwarded to the stripe-material, which is then pressed onto the main material through holes in the pipe.

Striped toothpaste was invented by a New Yorker named Leonard Lawrence Marraffino in 1955. The patent (US patent 2,789,731, issued 1957) was subsequently sold to Unilever, who marketed the novelty under the 'Stripe' brand-name in the early 1960s. This was followed by the introduction of the 'Signal' brand in Europe in 1965 (UK patent 813,514). Although 'Stripe' was initially very successful, it never again achieved the 8% market share that it cornered during its second year.

Marraffino's design, which remains in use for single-color stripes, is simple. The main material, usually white, sits at the crimp end of the toothpaste tube and makes up most of its bulk. A thin pipe, through which that carrier material will flow, descends from the nozzle to it. The stripe-material (this was red in 'Stripe') fills the gap between the carrier material and the top of the tube. The two materials are not in separate compartments. The two materials are sufficiently viscous that they will not mix. When pressure is applied to the toothpaste tube, the main material squeezes down the thin pipe to the nozzle. Simultaneously, the pressure applied to the main material causes pressure to be forwarded to the stripe material, which then issues out through small holes (in the side of the pipe) onto the main carrier material as it is passing those holes.

In 1990 Colgate-Palmolive was granted a patent (USPTO 4,969,767) for two differently-colored stripes. In this scheme, the inner pipe has a cone-shaped plastic guard around it, and about half way up its length. Between the guard and the nozzle-end of the tube is then a space for the material for one color, which then issues out of holes in the pipe. On the other side of the guard is space for second stripe-material, which has its own set of holes.

Striped toothpaste should not be confused with layered toothpaste. Layered toothpaste requires a multi-chamber design (e.g. USPTO 5,020,694), in which two or three layers then extrude out of the nozzle. This scheme, like that of pump dispensers (USPTO 4,461,403), is more complicated (and thus, more expensive to manufacture) than either the Marraffino design or the Colgate design.

Herbal toothpastes

Herbal toothpaste from Croatia

Herbal toothpastes are made from natural ingredients and some are even certified as organic. Many consumers have started to switch over to natural toothpastes in order to avoid synthetic and artificial flavors that are commonly found in regular toothpastes.[14] Due to the increased demand of natural products, most of the toothpaste manufacturers now produce herbal toothpastes. This type of toothpaste does not contain dyes or artificial flavors and this is one of the most common reasons that people claim when switching from regular toothpaste to herbal toothpaste.

Some people would rather use herbal toothpaste for their oral hygiene for a variety of reasons. Many are apparently opting for them because they are not tested on animals. Others, keen to protect the environment or who are sensitive to the ingredients in traditional toothpastes, are attracted to the fact that they contain no artificial colors or flavorings.[15] People who use homeopathic medicines are also attracted to toothpastes that do not contain mint because practitioners claim the herb may interfere with the effectiveness of their treatment. Herbal toothpastes are also fluoride-free, which appears to be another common reason why some people prefer this type of toothpaste over the regular one.

Also, people who have allergies or other health concerns may want to consider herbal or organic tooth paste formulations, which are widely available in natural food stores and through reputable Internet sites. These can be a good choice for people who are allergic to mint or to sodium laurel sulfate, a foaming agent that is included in most commercial toothpaste brands.[16]

Typical ingredients in herbal and organic toothpastes include herbs with established historical uses, such as myrrh to help kill plaque-causing bacteria; chamomile to decrease gum inflammation; Echinacea to stimulate the immune system; sage and rhatany to lessen bleeding; and essential oils, such as peppermint, to add flavor and relieve pain and inflammation. Other common ingredients in these products include ginger, clove and tea tree oils. Some brands also include fluoride, but most do not. Occasionally, mint flavorings can irritate the skin lining, the mouth and gums, so many homeopathic or natural toothpastes are mint-free.[16] Different brands use however different types of plants for the herbal toothpaste but some common ingredients are eucalyptus, myrrh, Chamomile, Sage and some other less known plants such as Lavang, Choti ilaychi, Saunf, Neem, Babool, Khadir. Herbal toothpastes also contain oils such as oils of coriander, ginger, lemon, and spearmint.

Eucalyptus is however one of the most common ingredients found in herbal toothpastes, mainly due to its properties of whitening and prevents stained teeth. Myrrh is used to prevent gingivitis and bad breath and Chamomile and Sage are said to be helpful in soothing mouth ulcers, toothaches and inflamed gums.[17]

Although many natural health practitioners are recommending herbal toothpastes, many of the health claims made for them have not been clinically proven. Only one range of herbal toothpastes has had its health claims approved by the BDHF - Kingfisher. However, health practitioners state that the lack of clinical trials should not necessarily put people off using herbal toothpastes as they are very expensive and most of the manufacturers do not have the financial means to carry them out. Dentists disagree that the regular toothpastes would pose a threat for one's health, as the chemicals found in these toothpastes are found in too small amounts to cause a health problem. Dentists recommend that people who are regularly using organic or herbal toothpaste are aware that the abrasives in some are not strong enough to clean one's teeth properly and they are advised to check with their dentist to make sure the toothpaste is doing its job. It is widely believed that brushing twice a day is sufficient to manage plaque - regardless of the type of toothpaste used.

People can also make their own herbal toothpaste with the help of the recipes that may be found all over the Internet. However, no one proved their efficiency nor their safety of use. Common ingredients of the home-made natural toothpaste are kaolin powder, baking soda, myrrh powder, raspberry leaf and herbs, spearmint, yellow dock and sage and essential oils. Anyhow, when using a toothpaste that has not been proven to be efficient in preventing periodontal diseases it is important to have regular checkups made with a dentist. These ingredients are however safe for one's health, but the efficiency of the toothpaste must be confirmed by a specialist in order to prevent different problems concerning the oral hygiene.

Alteration of taste perception

After using toothpaste, orange juice and other juices do not taste pleasant. This is due to the chemical interaction between stannous fluoride, a tin compound, in toothpaste and the acetic acid in the juices.[18] Sodium lauryl sulfate alters taste perception. It can break down phospholipids that inhibit taste receptors for bitterness, giving food a bitter taste. It is also thought to inhibit sweet receptors. In contrast, apple is known to taste more pleasant after using toothpaste.[19] Distinguishing between the hypotheses that the bitter taste of orange juice results from stannous fluoride or from sodium lauryl sulfate is still an unresolved issue and it is thought that the menthol added for flavor may also take part in the alteration of taste perception when binding to lingual cold receptors.

See also

Notes

  1. ↑ Dr. David Jones - Questions & Answers
  2. ↑ The History of Toothpaste and Toothbrushes
  3. ↑ 3.0 3.1 Sertima, Ivan Van (1992). The Golden Age of the Moor. Transaction Publishers. p. 267. ISBN 1560005815 
  4. ↑ Lebling Jr., Robert W. (July-August 2003). "Flight of the Blackbird". Saudi Aramco World: 24–33. http://www.islamicspain.tv/Arts-and-Science/flight_of_the_blackbird.htm. Retrieved 2008-01-28 
  5. ↑ "Other ingredients in toothpaste". http://www.toothpasteworld.com/history.htm. Retrieved 2007-12-23. 
  6. ↑ "MSNBC: Throw away Chinese toothpaste, FDA warns". http://www.msnbc.msn.com/id/18985512/. Retrieved 2007-12-23. 
  7. ↑ Calcium Phosphate Technologies from dentist.net
  8. ↑ 8.0 8.1 8.2 "Toothpaste". 2010-04-15. http://www.ada.org/1322.aspx. 
  9. ↑ "Triclosan: What Consumers Should Know". 2010-04-17. http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm205999.htm. 
  10. ↑ http://www.dentalgentlecare.com/cancer_sores_copy(1).htm
  11. ↑ Canedy, Dana (1998-03-24). Toothpaste a Hazard? Just Ask the F.D.A.. New York Times. http://query.nytimes.com/gst/fullpage.html?sec=health&res=9406E2D81338F937A15750C0A96E958260. Retrieved 2008-12-21 
  12. ↑ 12.0 12.1 Delivering Better Oral Health: An evidence-based toolkit for prevention. NHS. UK, 2007.
  13. ↑ Anil S. (2007). "Plasma cell gingivitis among herbal toothpaste users: a report of three cases.". J Contemp Dent Pract 8 (4): 60–6. PMID 17486188. http://thejcdp.com/issue033/anil/anil.pdf 
  14. ↑ "Natural Herbal Toothpaste". http://www.herbaltoothpaste.net/. Retrieved 2010-04-20. 
  15. ↑ "Should you use herbal toothpaste?". http://www.dailymail.co.uk/health/article-34857/Should-use-herbal-toothpaste.html. Retrieved 2010-04-20. 
  16. ↑ 16.0 16.1 "Tooth Paste". http://www.oramd.com/toothpaste/12-tooth-paste.htm. Retrieved 2010-04-20. 
  17. ↑ "Colgate Herbal Toothpaste". http://www.reviewstream.com/reviews/?p=43379. Retrieved 2010-04-20. 
  18. ↑ Orange Juice and Toothpaste. NEWTON: Ask A Scientist. United States Department of Energy website.
  19. ↑ DeSimone A., John; Heck, Gerard L.; Bartoshuk, Linda M. (1980). "Surface active taste modifiers: a comparison of the physical and psychophysical properties of gymnemic acid and sodium lauryl sulfate". Chemical Senses 5: 317–330. doi:10.1093/chemse/5.4.317 

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