Tooth

static/images/lower_wisdom_tooth.jpg

A human lower wisdom tooth.

A tooth (from Old English too) is a structure found in the jaws_ of many vertebrates that is used to break down food ("mastication"). Some animals, particularly carnivores, also use teeth for hunting or for defensive purposes.

The study of the structure, development, and abnormalities of teeth is called odontology (from Greek odous "tooth"). A person skilled in the prevention and treatment of diseases of the teeth and mouth is called a dentist (from French dent "tooth").

Contents

1   Function

static/images/SquirrelJaw.jpg

The jaw of a squirrel. [3]

static/images/FoxSkull.jpg

The skull of a fox. [3]

The type of teeth animals have depends on their diet. Herbivores have flat molars made for grinding plant tissues, which are often difficult to break down. Many herbivores (like squirrels and beavers) have chisel-like front teeth used for gnawing through wood or hard seeds. These teeth grow continually to avoid being worn down with use. Herbivores often have a gap between the front and back teeth to allow space for repositioning plant tissue as it's chewed, since much chewing is required to break it up.

Carnivores have long sharp teeth teeth which help them catch and tear into prey. The back teeth are often more narrow and sharply serrated, used to meat into smaller chunks.

Omnivores have a combination of both. In humans, teeth function to mechanically break down food by cutting and crushing them in preparation for swallowing and digestion.

1.1   Mastication

The jaw is an opposable structure at the entrance of the mouth used for grasping and manipulating good. In vertebrates, the jaws oppose vertically, comprising an upper jaw and a lower jaw. In mammals, the jaws are made up of the mandible (from Latin mandere "to chew" + -bula "tool"; lower jaw) and the maxilla (Upper jaw).

The mandible is the only movable bone of the human skull.

Losing your teeth decreases the angle of the mandible (gonial angle).

2   Substance

2.1   Structure

static/images/tooth_human_cross_section.png
static/images/tooth_nerves.jpg

Suggests why toothaches are related to headaches.

The teeth of most mammals consists of a root, a neck, and a crown.

The roots of teeth are embedded in the jaw and are covered by gums.

The anatomic crown of a tooth is the area covered in enamel above the cementoenamel junction (CEJ) or "neck" of the tooth. Most of the crown is composed of dentin.

2.2   Tissues

static/images/tooth_cross_section.jpg

Teeth are not made of bone, but rather four major tissues of varying density and hardness: enamel, dentin, cementum, and dental pulp.

2.2.1   Enamel

Enamel is a hard translucent tissue that makes up the visible part of the tooth, covering the crown. It is the hardest substance of the body. (In fact, enamel is harder than metal equipment used by dentists, enabling them to remove dental calculus from the teeth without damaging the enamel.)

Enamel contains the highest percentage of minerals (96%) of any substance in the body, in particular calcium and phosphorus_. The large amount of mineral accounts not only for its strength but also for its brittleness, which is similar to glass.

Enamel varies in thickness over the surface of the tooth. It is often thickest at the cusp, and thinnest at its border with the cementum.

Enamel is formed on the tooth while the tooth is developing within the gum, before it erupts into the mouth.

Ameloblasts_ are responsible for the formation of enamel.

2.2.2   Dentin

Dentin is a yellow mineralized connective tissue with an organic matrix of collagenous proteins. Dentin forms a layer of consistent thickness around the pulp cavity and comprises the bulk of the tooth.

Dentin is main component of carved ivory object.

2.2.3   Cementum

Cementum is a specialized bone like substance covering the root of a tooth.

Cementum forms a layer surrounding the dentin of tooth and tusk roots. Its main function is to adhere the tooth and tusk root the jaw bones.

2.2.4   Dental pulp

The dental pulp is the central part of the tooth filled with soft connective tissue. This tissue contains blood vessels and nerves that enter the tooth from a hole at the apex of the root. The pulp is commonly called "the nerve" of the tooth.

Odontoblastic cells line the pulp cavity and are responsible for the production of dentin.

3   Mouth

3.1   Gums

The gums are a `mucosal tissue`_ that cover the jaw and surround teeth. Gums are tightly bound to the underlying bone, which helps prevent resist the friction of food passing over them.

Healthy gums are usually "coral pink" in light skinned people.

Bleeding suggests inflammation that is possibly due to the accumulation bacterial plaque.

4   Classification

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Humans usually have 20 primary (deciduous, "baby" or "milk") teeth and 32 permanent (adult) teeth.

The teeth are divided into four types: incisors, canines, premolars, and molars, each with a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food.

4.4   Molars

Wisdom teeth may not fully erupt into the mouth because of blockage from other teeth ("impaction") due to a mismatch between the size of the teeth and the size of the jaw.

The eruption of wisdom teeth has been known to cause dental issues for centuries, at least as far back as Aristotle:

The last teeth to come in man are molars called 'wisdom-teeth', which come at the age of twenty years, in the case of both sexes. Cases have been known in women upwards. of eighty years old where at the very close of life the wisdom-teeth have come up, causing great pain in their coming; and cases have been known of the like phenomenon in men too. This happens, when it does happen, in the case of people where the wisdom-teeth have not come up in early years.

— Aristotle, The History of Animals

5   Growth

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A child's jaw before losing baby teeth.

Animals may develop one or more sets of teeth. For example, sharks grow a new set of teeth every two weeks. Rodent incisors grow and wear away continually through gnawing, which helps maintain relatively constant length.

6   Disease

6.1   Tooth decay

static/images/molar_with_decay.jpg

A molar with decay.

The high mineral content of enamel makes it susceptible to a demineralization process, which can form cavities.

The mouth contains a great number and variety of bacteria_ which coat the surface of teeth. This coating is called plaque. The main microorganisms are Streptococcus mutans and various anaerobic organisms. These microorganisms are all naturally present in the mouth, and are normally harmless.

In the absence of oxygen, these bacteria ferment_ sucrose in the mouth, producing `lactic acid`_ and a calcium phosphate deposit called tartar or dental calculus, which can only be removed through professional cleaning. The lactic acid decreases the pH in the mouth, which causes calcium and phosphorus in the enamel to dissolve. (Human saliva maintains the ph in the mouth between 6 and 7. Dogs are less likely to have tooth decay than humans because of the high pH of dog saliva.) This process, known as demineralisation, allows for bacteria to further invade the tooth. When enamel is unable to prevent encroachment of bacteria, the underlying dentin may decay, leading to tooth destruction

The frequency of sugar ingestion, not the amount, is the most important factor in the causation of tooth decay. When the pH in the mouth initially decreases from the ingestion of sugars, the enamel is demineralized and left vulnerable for about 30 minutes as saliva gradually neutralizes the acids. Eating a greater or less quantity of sugar in one sitting does not affect the time of demineralization.

If there is sufficient time between the intake of food, dissolved minerals (i.e. calcium and phosphate) can be remineralized into the enamel, limiting the impact. Fluoride catalyzes this remineralization process. It also binds to the byproducts of the reaction creating a new tooth surface containing fluoridated hydroxyapatite and fluorapatite, which is less soluble than natural mineralized enamel (hydroxyapetite).

Saliva is saturated with calcium and phosphate ions. However, saliva is unable to penetrate through plaque.

Humans cannot regenerate enamel. Teeth become more yellow as the enamel layer thins and the yellow dentin layer becomes more visible.

6.2   Gum disease

Gum disease (= periodontal disease) is a set of diseases affecting the tissues surrounding the teeth.

Gingivitis is a disease that causes irritation of the gums. It can cause gums to bleed after brushing or flossing.

Gingivitis can be treated by removing placque.

Gingivitis is reversible with good oral hygiene. Without, it can precede periodontitis_.

Periodontitis is a disease in which the gums pull away from the tooth, and the teeth may loose or fall out.

7   Restorations

A restoration refers to ...

Most dental restorations involve the removal of enamel. Frequently, the purpose of removal is to gain access to the underlying decay in the dentin or inflammation in the pulp.

7.1   Fillings

A dental filling or restoration is a procedure to restore the form and function of a tooth that’s been damaged, usually by decay. After the dentist removes any decay or infected tissue, a filling is placed to prevent further damage and restore the tooth. Several materials can be used for fillings, including plastics, metals, glass resins and porcelain. Some fillings wear down faster than others, and the more durable ones tend to be more expensive.

Here are the average national prices for three common filling materials for molars and the most common filling for a front tooth, which is white resin composite:

  • Amalgam (silver), back tooth: $132
  • Resin composite (white), front tooth: $155
  • Resin composite (white), back tooth: $170
  • Gold crown, back tooth: $1,123

https://www.nerdwallet.com/blog/health/medical-costs/how-much-does-a-filling-cost/


Doing pretty huge fillings like this is a little controversial as far as longevity, as a tooth that heavily undermined and restored is much more prone to crack down the line due to chewing forces.

7.2   Dental amalgam

Dental amalgam is a dental filling material used to fill cavities caused by tooth decay. It has been used for more than 150 years in hundreds of millions of patients around the world. [4]

Dental amalgam is a mixture of metals, consisting of liquid (elemental) mercury and a powdered alloy composed of silver, tin, and copper. Approximately 50% of dental amalgam is elemental mercury by weight. The chemical properties of elemental mercury allow it to react with and bind together the silver/copper/tin alloy particles to form an amalgam. [4]

When placing dental amalgam, the dentist first drills the tooth to remove the decay and then shapes the tooth cavity for placement of the amalgam filling. Next, under appropriate safety conditions, the dentist mixes the powdered alloy with the liquid mercury to form an amalgam putty. This softened amalgam putty is placed and shaped in the prepared cavity, where it rapidly hardens into a solid filling. [4]

Approximately half of a dental amalgam filling is liquid mercury and the other half is a powdered alloy of silver, tin, and copper. Mercury is used to bind the alloy particles together into a strong, durable, and solid filling. Mercury’s unique properties (it is a liquid at room temperature and that bonds well with the alloy powder) make it an important component of dental amalgam that contributes to its durability. [4]

Benefits:

  • Dental amalgam fillings are strong and long-lasting, so they are less likely to break than some other types of fillings.
  • Dental amalgam is the least expensive type of filling material.

Potential risks:

  • Dental amalgam contains elemental mercury. It releases low levels of mercury in the form of a vapor that can be inhaled and absorbed by the lungs. High levels of mercury vapor exposure are associated with adverse effects in the brain and the kidneys.

    FDA has reviewed the best available scientific evidence to determine whether the low levels of mercury vapor associated with dental amalgam fillings are a cause for concern. Based on this evidence, FDA considers dental amalgam fillings safe for adults and children ages 6 and above. The weight of credible scientific evidence reviewed by FDA does not establish an association between dental amalgam use and adverse health effects in the general population. [4]

7.3   Resin composite

Resin composite fillings are made of ceramic and plastic compounds. Because resins mimic the appearance of natural teeth, these fillings have been used in front teeth for years. When they first appeared, however, resin compounds weren't strong enough to be used in back teeth, where high-pressure grinding and chewing require greater durability.

In the past 10 years, technology has improved enough to allow the use of resin material in posterior or back teeth.

Resin costs more than amalgam, which can make the cost of the service higher than for a comparable amalgam filling.

For these reasons, the majority of dental health carriers pay for coverage of resin fillings in teeth that are visible in a patient's smile.

8   Maintenance

8.1   Oral hygiene

Oral hygiene is the practice of keeping the mouth clean and is a means of preventing dental caries, gingivitis, periodontal disease, bad breath, and other dental disorders. It consists of both professional and personal care. Regular cleanings, usually done by dentists and dental hygienists, remove tartar (mineralized plaque) that may develop even with careful brushing and flossing.

The purpose of cleaning teeth is to remove plaque. Healthcare professionals recommend regular brushing twice a day (in the morning and in the evening, or after meals) in order to prevent formation of plaque and tartar.

Dental hygiene does not try to kill bacteria. It only tries to break up the biofilms that form plaque and tartar.

A toothbrush is able to remove most plaque, except in areas between teeth. As a result, flossing is also considered a necessity to maintain oral hygiene. When used correctly, dental floss removes plaque from between teeth and at the gum line, where periodontal disease often begins and could develop caries.

8.1.1   Toothbrush

A toothbrush is a device that consists of a head of tightly clustered bristle_ mounted on a handle.


Brushing too hard, or with a hard bristle toothbrush, cannot damage enamel. It CAN however, damage the gum tissues and/or the cementum (a much softer layer that covers the root surface) of a tooth.

Brush too hard => damaged gums => recession => exposed cementum => damage or removal of cementum => sensitivity, root surface cavities (BAD!!)


Gum erosion is what you are trying to avoid with a soft brush and moderate pressure. The tooth under the gums doesn't have the same protective coating and is super sensitive.

The dentist / hygienist is carefully scraping around the gum line to ensure they don't damage the gums.

8.1.2   Toothpaste

Toothpaste is ...

One of the oldest ingredients used to help remove plaque from your teeth is baking powder. All you need to do is empty a little baking soda into a bowl, wet your toothbrush, dab a bit of the powder onto your brush and use it to clean the plaque.

Another alternative is adding a dash of salt along with baking soda and using this mixture to brush and get rid of tartar.

8.1.3   Dental floss

Dental floss is a cord of thin filaments (such as nylon) used to remove food and dental plaque from between teeth in areas a toothbrush is unable to reach.

Floss may be coated in wax_ for flavor.

Floss was not commercially available until 1882.

8.1.4   Mouthwash

Mouthwash is ... For example, Listerine.


Creating your own mouthwash is simple; all you require is baking soda (half cup), water (one glass), essential lemon oil (10 drops), aloe vera gel (one teaspoon), and vegetable glycerin (four teaspoons). Store the mixture in a bottle and use it on a daily basis.


You don't need mouthwash. You just need good brushing technique, flossing, and a conscious diet. [2]

Mouthwashes don't do very much aside from making your breath smell nice. [2] Specifically in terms of benefits for your gums: regular flossing, mild stimulation with a brush, and a cleaning every few months are more than adequate solutions to gum disease. [2]

Alcohol containing mouthwashes are kinda iffy in that alcohol compromises the integrity of the cell membranes. This can lead to the carcinogens (such as the ones in smoke) that are in your mouth to more easily go into the cells in your mouth and thus interact with the DNA and cause mutations. [2]

The mouthwash industry is valued at $689 million a year. [1]

Since the mid-1980s, six-month trials have repeatedly shown that using mouthwash actually has an appreciable effect on plaque and gingivitis, though to varying degrees. In one meta-analysis comparing prescription-strength and over-the-counter solutions, products like Listerine wound up reducing dental plaque in patients by between 13 percent and 56 percent, with a reduction in gingivitis of between 14 percent and 36 percent. Non-alcoholic rinses, such as Crest Pro-Health, had a 15 percent effect on plaque and gingivitis, respectively. [1]

8.2   Removal

How a wisdom tooth is removed.

9   Cosmetics

9.2   Whitening

Whiteners are not regulated by the FDA because they are considered cosmetics.

The American Dental Association provides it seal for some products. When a manufacturer applies for the seal, an independent panel of dentists analyzes the company's data and sometimes performs studies of their own. [6] Only one over-the-counter-bleaching product carries the ADA seal — Crest 3D White Glamorous White Whitestrips. [6] [7]

Most cause some tooth sensitivity during the bleaching process, but that goes away once the process is complete, she says. Depending on which product is used, bleaching can take anywhere from two to six weeks. [6] And, if you're not careful, Sahota says the products can leak onto the gums, causing inflammation and "extra sensitivity" to pressure, temperature and touch. [6]

A safer but more costly option might be to buy a custom-made tray from your dentist, Sahota says. Unlike the one-size-fits-all trays sold over the counter, a dentist makes the tray "just for you" she says. [6]

The tray hugs the teeth and ensures the gel is kept where it should be and is evenly applied. The kits cost about $400 [≈ cost of a suit]; this at-home whitening process can take up to four weeks, depending on how stained the teeth are to begin with. Generally, the trays are worn for one or two hours a day. [6]

If you want an even faster route, you'll have to pay more. Bleaching in the dental office can run more than $1,000 [≈ Traditional cell phone cost per year], but results are quick and more dramatic. Dentists use bleaching gels that rely on high concentrations of hydrogen peroxide (up to 40 percent hydrogen peroxide, compared to a 5 to 6 percent concentration in drugstore kits and a 10 to 15 percent solution in the home-kits from dentists). [6]

An important caveat: Insurance companies consider in-office teeth whitening "cosmetic" so the procedures are almost never covered. [6]

"Tooth discoloration can be caused by cavities and other oral problems," she says. "It's more important to maintain healthy teeth."

It's also important to note that not all stains are the same. Some are mostly on the surface of the teeth and come from consuming lots of dark colored liquids like coffee, tea and red wine, as well as foods with vibrant yellow spices like turmeric. The tar and nicotine from cigarettes are also huge culprits. Often surface stains can be diminished by routine brushing, flossing and biannual professional cleaning in the dentist's office. [6] Unfortunately, there are deeper stains you just can't avoid by being careful about what you eat and drink. These come with aging and years of chewing, which causes millions of tiny cracks in the outer enamel of the tooth. These cracks can fill up with stain. On top of that, the thinning enamel can allow the yellow core of the tooth to become more visible. Grinding teeth at night and brushing too hard can also weaken and thin tooth enamel. Bleaching agents can penetrate these deeper stains and turn the tooth whiter — typically two to seven shades lighter. [6]

All types of bleaching — whether over-the-counter, take-home kits or in the dental office — are temporary, requiring touch-ups at some point. As for homespun remedies promoted online, in social media and in magazines as being "natural whitening" agents (including charcoal, baking soda or lemon juice), the ADA says there is no evidence these methods work. [6]

Tooth whiteners in toothpastes work through a mechanical action. They have mild abrasives which aid in the removal of stains on enamel. Although this can be an effective method, it does not alter the intrinsic color of teeth

Lemon juice (an acid) and `baking soda`_ (an abrasive) can be combined to whiten teeth. The acid eats away at the outer layer of enamel while the abrasive scrubs the outer enamel. [2]


Also, the "whitening" toothpastes don't really whiten the way white strips do. The toothpaste whitening just polishes away surface enamel stains. Regular whitening (ie. Crest whitening strips, Zoom, etc.) uses carbamide or hydrogen peroxide to penetrate the enamel and whiten dentin (the second layer which is the layer mostly responsible for the color of your teeth).


  • Charcoal toothpaste
  • Laser teeth whitening
  • Whitening trays from dentists

Some options:

  • Crest 3D White Whitestrips ($32 on Amazon)

    Recommended by a dental student to buy the "Glamorous White"

    Does whiten teeth and effects last for years.

    They are banned in the UK and other countries because they strip the enamel from teeth and cause damage. Some people report that after just one use, they suffer from intense pain because of increased sensitivity.

  • Sporting Smiles https://www.sportingsmiles.com/teeth-whitening.html

  • 5 dollar smile club https://5dollarsmileclub.com/

10   Dentistry

Consider the maxim that everyone should visit the dentist twice a year for cleanings. We hear it so often, and from such a young age, that we’ve internalized it as truth. But this supposed commandment of oral health has no scientific grounding. Scholars have traced its origins to a few potential sources, including a toothpaste advertisement from the 1930s and an illustrated pamphlet from 1849 that follows the travails of a man with a severe toothache. Today, an increasing number of dentists acknowledge that adults with good oral hygiene need to see a dentist only once every 12 to 16 months. [5]

As a profession, dentistry has not yet applied the same level of self-scrutiny as medicine, or embraced as sweeping an emphasis on scientific evidence. “We are isolated from the larger health-care system. So when evidence-based policies are being made, dentistry is often left out of the equation,” says Jane Gillette, a dentist in Bozeman, Montana, who works closely with the American Dental Association’s Center for Evidence-Based Dentistry, which was established in 2007. “We’re kind of behind the times, but increasingly we are trying to move the needle forward.” [5]

The Cochrane organization, a highly respected arbiter of evidence-based medicine, has conducted systematic reviews of oral-health studies since 1999. In these reviews, researchers analyze the scientific literature on a

particular dental intervention, focusing on the most rigorous and well-designed studies. In some cases, the findings clearly justify a given procedure. For example, dental sealants—liquid plastics painted onto the pits and grooves of teeth like nail polish—reduce tooth decay in children and have no known risks. (Despite this, they are not widely used, possibly because they are too simple and inexpensive to earn dentists much money.) But most of the Cochrane reviews reach one of two disheartening conclusions: Either the available evidence fails to confirm the purported benefits of a given dental intervention, or there is simply not enough research to say anything substantive one way or another. [5]

Fluoridation of drinking water seems to help reduce tooth decay in children, but there is insufficient evidence that it does the same for adults. Some data suggest that regular flossing, in addition to brushing, mitigates gum disease, but there is only “weak, very unreliable” evidence that it combats plaque. [5]

Fluoridation of drinking water seems to help reduce tooth decay in children, but there is insufficient evidence that it does the same for adults. Some data suggest that regular flossing, in addition to brushing, mitigates gum disease, but there is only “weak, very unreliable” evidence that it combats plaque. [5]

In medieval Europe, barbers didn’t just trim hair and shave beards; they were also surgeons, performing a range of minor operations including bloodletting, the administration of enemas, and tooth extraction. Barber surgeons, and the more specialized “tooth drawers,” would wrench, smash, and knock teeth out of people’s mouths with an intimidating metal instrument called a dental key: Imagine a chimera of a hook, a hammer, and forceps. [5]

Barber surgeons came to America as early as 1636. By the 18th century, dentistry was firmly established in the colonies as a trade akin to blacksmithing. Itinerant dentists moved from town to town by carriage with carts of dreaded tools in tow, temporarily setting up shop in a tavern or town square. They yanked teeth or bored into them with hand drills, filling cavities with mercury, tin, gold, or molten lead. [5]

In the mid-19th century, a pair of American dentists began to elevate their trade to the level of a profession. From 1839 to 1840, Horace Hayden and Chapin Harris established dentistry’s first college, scientific journal, and national association. [5]

Whatever happened, from that point on, “the professions of dentistry and medicine would develop along separate paths,” writes Mary Otto, a health journalist, in her recent book, Teeth. Becoming a practicing physician requires four years of medical school followed by a three-to-seven-year residency program, depending on the specialty. Dentists earn a degree in four years and, in most states, can immediately take the national board exams, get a license, and begin treating patients. (Some choose to continue training in a specialty, such as orthodontics or oral and maxillofacial surgery.) When physicians complete their residency, they typically work for a hospital, university, or large health-care organization with substantial oversight, strict ethical codes, and standardized treatment regimens. By contrast, about 80 percent of the nation’s 200,000 active dentists have individual practices, and although they are bound by a code of ethics, they typically don’t have the same level of oversight. [5]

Dentistry’s academic and professional isolation has been especially detrimental to its own scientific inquiry. Most major medical associations around the world have long endorsed evidence-based medicine. The idea is to shift focus away from intuition, anecdote, and received wisdom, and toward the conclusions of rigorous clinical research. Although the phrase evidence-based medicine was coined in 1991, the concept began taking shape in the 1960s, if not earlier (some scholars trace its origins all the way back to the 17th century). In contrast, the dental community did not begin having similar conversations until the mid-1990s. There are dozens of journals and organizations devoted to evidence-based medicine, but only a handful devoted to evidence-based dentistry. [5]

Studies that explicitly focus on overtreatment in dentistry are rare, but a recent field experiment provides some clues about its pervasiveness. A team of researchers at ETH Zurich, a Swiss university, asked a volunteer patient with three tiny, shallow cavities to visit 180 randomly selected dentists in Zurich. The Swiss Dental Guidelines state that such minor cavities do not require fillings; rather, the dentist should monitor the decay and encourage the patient to brush regularly, which can reverse the damage. Despite this, 50 of the 180 dentists suggested unnecessary treatment. Their recommendations were incongruous: Collectively, the overzealous dentists singled out 13 different teeth for drilling; each advised one to six fillings. [5]

The financial burden of entering the profession is high and rising. In the U.S., the average debt of a dental-school graduate is more than $200,000. And then there’s the expense of finding an office, buying new equipment, and hiring staff to set up a private practice. A dentist’s income is entirely dependent on the number and type of procedures he or she performs; a routine cleaning and examination earns only a baseline fee of about $200. [5]

In parallel with the rising cost of dental school, the amount of tooth decay in many countries’ populations has declined dramatically over the past four decades, mostly thanks to the introduction of mass-produced fluoridated toothpaste in the 1950s and ’60s. In the 1980s, with fewer genuine problems to treat, some practitioners turned to the newly flourishing industry of cosmetic dentistry, promoting elective procedures such as bleaching, teeth filing and straightening, gum lifts, and veneers. [5]

Also how does one get a second opinion? Is that covered by insurance?

Strategy: for several cleanings in a row, use different dentists in your area (cleanings spaced however your insurance does it). this way if/when you need larger work, you can go to a previous dentist for 2nd opinion, they have older xrays to compare to, and you have a history with them. Makes a huge difference.

.

Say what you want about doctors, I've never walked into a medical examination room covered in posters explicitly trying to sell me shit.

If you go to a plastic surgery clinic I expect you'd see that. Cosmetic dentistry is similarly elective.

.

Yes, my treatment plan is different than the guys down the street. Does it make me wrong? No. Does it make him wrong? No. Different education, experience, and philosophies will yield different treatment options and different professional opinions. And it is just that - an opinion. The saying is not "getting a second fact", it is "getting a second opinion."

It's a lonely world out there as a dentist... Typically you are the only provider in the office. And unlike our physician counterparts who often have a team of specialists at their fingertips in a hospital or group practice setting, the dentist is expected to be the expert of all things oral health. Fillings, crowns, cosmetics, surgery, root canals, pediatrics, oral pathology, etc. It's no wonder when you ask ten dentists about one patient you will get eleven different treatment plans.

11   History

Tooth decay was low in pre-agricultural societies, the growth in farming society about 10,000 years ago correlated with an increase with the rate of cavities.

12   Further reading

13   References

[1](1, 2) Brian Fung. Apr 17, 2012. Mouthwash: Does It Really Work? http://www.theatlantic.com/health/archive/2012/04/mouthwash-does-it-really-work/256024/
[2](1, 2, 3, 4, 5) Is using mouthwash products such as Listerine actually beneficial to your gums? Are there any adverse effects? https://www.reddit.com/r/askscience/comments/1ljqvi
[3](1, 2) Dr. Mary Kathryn Whitson. Animal adaptations. http://www.nku.edu/~whitsonma/Bio120LSite/Bio120LReviews/Bio120LAnimalRev.html
[4](1, 2, 3, 4, 5) About Dental Amalgam Fillings. https://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/DentalProducts/DentalAmalgam/ucm171094.htm
[5](1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13) Ferris Jabr. May 2019. The Trouble with Dentistry. https://www.theatlantic.com/magazine/archive/2019/05/the-trouble-with-dentistry/586039/
[6](1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11) Patti Neighmond. 2017-08-14. Navigating The 'Aisle Of Confusion' To Whiten Your Teeth. https://www.npr.org/sections/health-shots/2017/08/14/542830158/navigating-the-aisle-of-confusion-to-whiten-your-teeth
[7]American Dental Association. 2017-06-19. Crest 3D White Glamorous White Whitestrips to Receive ADA Seal of Acceptance. https://www.ada.org/en/press-room/news-releases/2017-archives/june/crest-3d-white-glamorous-white-whitestrips-to-receive-ada-seal-of-acceptance

Some city governments add fluoride to the tap water to improve public health. The first deliberate fluoridation began in Grand Rapids, MI. Some places, including most of Europe, have naturally high levels of fluoride in their water sources. However, many regions in the United States do not.