5 Common Dental Myths

Is putting the pain reliever next to your aching tooth better than swallowing it? We'll explore that dental myth.

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It's no myth that dental work can be a little scary sometimes. In fact, as many as 12 percent of adults in the U.S. say they get anxious about visiting the dentist, so if the thought of reclining in a dental chair makes you twitchy, you're not alone [source: Sohn]. Some people get so worked up about it that they choose to just stay away: According to a report by the Surgeon General's office, 4.3 percent of Americans are so afraid of going to the dentist that they simply don't go [source: Department of Health and Human Services].

With so much unnecessary stress and anxiety built up around dentists and dental health, it's not surprising that we've made up several myths over the years to help explain or even alleviate our dental issues. Sometimes we choose to believe these myths rather than find out the truth and, after a while, they can become so ingrained in our culture that it's hard to tell fact from fiction.

But when it comes to your dental health, having false information can be harmful. Here we'll "drill down" to the truth behind five common dental myths, some of which you may have even believed yourself.

Overusing bleaching agents may make your teeth sensitive but it won't weaken them.

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5: Bleaching Weakens Teeth

We'd all like our pearly whites to be whiter, and sometimes regular brushing and flossing just doesn't cut it. Luckily there's a host of whitening products available over the counter or through the dentist -- from gels to pastes to strips -- to help fool Mother Nature and make our teeth look better.

But some people worry that using bleaching products on their teeth can be harmful or that they can weaken the teeth. Is there any basis behind this fear? Not really. Bleaching products are generally harmless if used according to the directions. That's because teeth bleaching only affects the color of the teeth, not their health or strength [source: Today Health]. Bleaching works by removing some of the teeth's pigmentation, and if you bleach them too much and remove too much of the natural pigmentation, your teeth might begin to appear translucent [source: Johnston]. Some people could mistake this translucency for weakening of the enamel or damage to the teeth, but that's not the case -- it's just a color change.

Side effects of too much bleaching include temporary tooth sensitivity and irritated gums, but there's no need to fear that using bleaching products will weaken your teeth [source: Today Health].

CAN YOU BRUSH TOO MUCH?

Most dentists recommend brushing your teeth two or three times a day, but brushing more than that is unnecessary and could actually damage or irritate the gums and wear away tooth enamel, especially if you're brushing too hard. [source:Doheny].

4: Brushing's Bad for Bleeding Gums

On the surface this myth might make sense -- if yourgums are bleeding it seems logical that you would leave them alone until they heal. But when it comes to your gums, the opposite is true. When your gums bleed, it's a sign that plaque and food particles are accumulating along your gum line and the gums have become irritated and inflamed. You need to brush to remove the gunk if you want the bleeding to stop [source: Dillon]. Your gums might also bleed if you're flossing harshly or flossing for the first time, or the first time in a while, and your gums aren't used to it [source: WebMD].

The key is to brush and floss regularly and gently. Dentists recommend holding your toothbrush so that the bristles are at a 45-degree angle to your teeth, with the bristles pointing toward your gums. This is the most effective way to remove gum line plaque by brushing [source: American Dental Association]. When you floss, don't force the floss between the teeth -- instead, gently slide the floss back and forth, following the curve of the tooth, until it slips between your teeth [source: WebMD]. It may take some time, but eventually the bleeding and soreness will go away. If it doesn't, it may be a sign of a more serious problem and you should see your dentist [source: Dillon].

3: Bad Breath Means You're a Bad Brusher

Actually, bad breath can be caused by several factors, only one of which is poor dental hygiene. The foods you eat are a major culprit -- a stomach full of garlic and onions is bound to give your breath a foul odor, no matter how much you brush and floss. And what about sicknesses like pneumonia? Nobody wants to kiss you when you've got that, and it's not just because they want to avoid getting sick -- certain illnesses can give you bad breath as well. So don't be too quick to judge when that close-talking colleague offends with his foul smelling breath -- it may not be his fault!

And how about your own oral odors? As long as you follow the dentist's recommendation of brushing and flossing at least twice a day, and you visit your dentist at least twice each year for regular checkups, you can be pretty sure your bad breath is not a dental hygiene issue. But if you're still worried about stinky breath, ask your dentist about it -- he or she can determine if any odors related to dental hygiene or if they're caused by something else [source: WebMD].

2: The More Sugar you Eat, the Worse for your Teeth

You're just about to take a big bite of something decadently sweet, perhaps some sticky taffy or a double chocolate candy bar, when you hear a nagging voice in your head saying, "If you eat that, your teeth will fall out!" Sound familiar? Many of us can recall being told that if we eat too many sugary foods they will destroy our teeth. But did you know that the amount of sugar you eat is not the deciding factor in tooth decay?

The bacteria in your mouth feed on carbohydrates, like sugar, and produce an acid that eats away at the enamel of your teeth. The longer the sugar is in your mouth, the longer the bacteria can feed and produce acid, and the longer the acid can work on the enamel [source: Fries]. In other words, it's not about the amount of sugar you eat, it's about how long the sugar is in contact with your teeth [source: ScienceDaily].

This means that eating three candy bars, then immediately brushing your teeth, is less harmful to your dental health than eating one candy bar without brushing. Slowly dissolving candies, like lollipops, are also a bad idea, as is sipping on sugary drinks all day, since both situations allow sugar to hang around your teeth for a long time.

So the moral of this story is this: enjoy the sweets, but make sure you brush afterward!

1: An Aspirin Directly on a Tooth Will Relieve Pain

This one's an old at-home remedy, and it's completely false -- you should never put aspirin directly on or near an aching tooth. After all, you wouldn't put aspirin on your forehead if you had a headache, would you?

The only safe and effective way to take an aspirin tablet is to swallow it. When you swallow aspirin, it gets absorbed into your body through your digestive tract. It then enters your bloodstream and travels throughout your body. Aspirin works by stopping the production of prostaglandins, molecules that send pain messages from the injured part of your body to your brain. When the aspirin reaches your aching tooth, it inhibits prostaglandin production there, reducing the pain you feel [source: National Institutes of Health]. So even though it may be tempting to bypass the digestive process by putting the aspirin directly on your tooth, it just doesn't work that way.

Need another reason to put this ineffective rumor to rest? Placing aspirin directly on the aching tooth or your gums can cause an acidic chemical burn to your gums and lips. So if the pain of a toothache isn't bad enough, you'll have to deal with more pain when the aspirin leaves a sore in your mouth [source: Fries].

http://health.howstuffworks.com/wellness/oral-care/problems/5-common-dental-myths6.htm

Mummy offers evidence of early dental specialists

October 31, 2012 -- Just in time for Halloween ... High-resolution CT has given researchers a better look at a unique dental intervention previously discovered in a mummy that is thousands of years old. Their findings provide evidence of dental specialists practicing in ancient Egypt.

For the past several decades, CT has enabled researchers to examine mummies without damaging the remains and study ancient mummification processes, as well as the humans' health status -- including dental condition -- at the time of death.

Now researchers have used multidetector-row CT to image the mummies from the Redpath Museum at McGill University in Montreal. The dental findings of one male mummy in particular piqued the researchers' interest for further study as the CT images show a unique example of early dental intervention in ancient Egypt (International Journal of Paleopathology, October 3, 2012).

The mummy had "dental packing of a large interproximal carious lesion with a protective linen barrier," the researchers reported. "The dental packing ... is unique among ancient Egyptian mummies studied to date, and represents one of only a few recorded dental interventions in ancient Egypt," lead author Andrew D. Wade, PhD, and colleagues wrote. "Such a finding lends further support for the existence of a group of dental specialists practicing interventional medicine in ancient Egypt."

Click image to enlarge.

RM2718 gets placed in the CT scanner at the Montreal Neurological Institute and Hospital. Image courtesy of Nicholas Morin.

Wade has a doctorate in archaeological sciences and is a research fellow in the anthropology department at the University of Western Ontario. His research involves "medical imaging of mummies and skeletons, and analyzing their remains to learn more about people, societies, and diseases in the past," Wade wrote on his blog, "Are You My Mummy?"

Wade is also the database administrator for the international In­ternet-based Mummy Picture Archive and Communication Technology (IMPACT) Radiological Mummy Database at the university. The database is a multi-institutional collaborative research project devoted to the study of mummified remains using nondestructive medical imaging technologies.

Ancient dentistry 101

Ancient and classical texts indicate the existence of a dental profession that attempted to ease the pain and discomfort of dental disease, according to the study authors. Ancient toothache remedies included bitumen, cedar oil, wild olive gum, and fig juice on wool inserted into the cavity -- and, of course, extraction. Egyptian medical texts mention other dental remedies, including preventing tooth loss and how to "fasten a tooth" with ochre, honey, frankincense, and malachite.

Later the Greeks and Romans described filling materials and methods that included shredded alum wrapped in wool and inserted into the cavity, or filling with lint or lead and extracting the tooth.

Click image to enlarge.

RM2718 undergoes a whole-body CT scan. Image courtesy of Nicholas Morin.

There are examples of prostheses, but the authors stated that there is "serious doubt over their use in the lifetime of the individual, and these may represent embalming prostheses intended to restore the natural form of the mummy for its use in the afterlife," just as other body parts were repaired or replaced by embalmers.

While dental remedies are described in ancient texts, little physical evidence exists of interventional dental practices, making the Redpath Museum mummy with dental packing an interesting case study, the authors noted.

Imaging and radiocarbon dating

The mummy, known as the Theban Male (RM2718), is a young adult male that was acquired by Montreal politician James Ferrier during a trip to Egypt in 1859, according to co-author Barbara Lawson, curator of world cultures at the Redpath Museum.

In 1995, the mummy was imaged using plain film radiographs and CT with 3-mm slice thickness. His teeth were later examined by Odin Langsjoen, DDS, of the University of Minnesota-Duluth. "A dense rounded mass was noted in the largest of the carious lesions, which indicated that the individual may have received medical treatment during life," the authors reported.

In April 2011, the museum's mummy collection, which included two other female human mummies, was reimaged with higher-resolution CT as part of the IMPACT project. Wade and colleagues reported their findings of all three mummies earlier this year (RadioGraphics, July-August 2012, Vol. 32:4, pp. 1235-1250). They estimated the male mummy's age at death to be 20 to 30 years based on dental eruption and skeletal features.

Video from 3D reconstruction CT images of the dental packing in the left first and second molars. Video courtesy of the International Journal of Paleopathology.

The whole-body CT scans were performed at the Montreal Neurological Institute and Hospital using an Aquilion One 320-slice scanner (Toshiba America Medical Systems) with 0.5-mm-thick slices, offering much greater detail than the CT imaging performed in 1995 and also the ability to create 3D reconstructions, using Vital Images' Vitrea software and OsiriX software.

"We wanted to look closer at the dental packing because it is unique, so far, in published accounts of mummified human remains from Egypt," Wade wrote in an email to DrBicuspid.com. "We wanted to showcase the power of the recent scanning technology, too, in the hopes that more rescanning is done on mummies. CT scans from the '90s were great at the time, but we've come a long way in terms of spatial resolution."

In addition, in the fall of 2011, the mummy's outer linen wrapping underwent radiocarbon analysis, which dated the mummy as being from the Ptolemaic Period at approximately 350-360 before the common era (BCE) -- much younger than the New Kingdom Period (1550-1069 BCE) previously thought based on the museum's records.

Click image to enlarge. Curved planar reformatted CT image. Note the carious lesions on the left first and second molars. Image courtesy of Andrew D. Wade, PhD.

Click image to enlarge.

Multiplanar reformatted CT slices showing the packing material in the large interproximal carious lesion. Image courtesy of the International Journal of Paleopathology.

Dental findings

Overall, the dental condition of the mummy is poor, the researchers reported. The maxillary and mandibular teeth show occlusal attrition and abrasion, while the maxillary teeth also have numerous periapical abscesses and large interproximal carious lesions.

"Abscesses were found at the apices of the maxillary right first molar and second incisor and of the left first incisor and molars," they wrote. "The abscesses of the left maxillary molars communicate with the maxillary sinus and inferior meatus. Interproximal caries are noted in the maxillary right second premolar."

In fact, the dental condition of the young man may have caused his death. "An infection, such as that seen here extending into the sinuses, was likely accompanied by substantial pain and swelling during the life of this individual, and may have ultimately led to his death," Wade and colleagues wrote.

The researchers also identified the mass previously found by Dr. Langsjoen in the carious lesions of the left first and second molars, and described it as a low-density, homogeneous ball of material, such as linen. It measures 7.7 x 7.1 x 3.7 mm, larger than the lesion's opening of 5.5 x 6.8 mm, but it remains loose within the cavity, they noted.

The mass is evidence of "therapeutic dental packing" that was used before death, according to the authors. No antemortem dental packing has been identified before, and this wasn't done postmortem, as the mass was not formed to the tooth's shape for a lifelike appearance and function in the afterlife, and not all of the cavities are filled, they explained. Also, the material wouldn't have been able to restore strength or stability to the tooth. But it may have delivered a medicine such as cedar oil or fig juice to treat the pain, prevented food particles from entering the cavity, and protected the nerve from contact with the tongue or foreign bodies, they noted.

The researchers also pointed out the unusual appearance of the maxillary left first and right second incisors, which are smooth and flat with the same chiseled shape. The pulp chambers of both are exposed anteriorly, but the incisor in between doesn't have the same damage.

Sweet tooth?

Heavy attrition and abrasion are the most common dental conditions of the ancient Egyptians, often resulting in periapical abscesses from the exposure of the pulp to bacteria, according to the researchers. The cause is due to the Egyptian diet, which consisted in large part of coarse-milled flour that was often mixed with millstone debris and sand from the desert, they noted.

"The heavy occlusal wear resulting from chewing these components is evident in both noble and commoner mummies throughout Egyptian history and even in modern Egyptian farmers," Wade and colleagues wrote. "While the high level of attrition serves to wear smooth the pits and grooves where cariogenic bacteria adhere, the high-carbohydrate component of the ancient Egyptian diet, including bread and a weak porridge-like beer, was still a cariogenic risk for nonocclusal surfaces."

Click image to enlarge.

3D reconstruction shows the worn incisors. Image courtesy of Andrew D. Wade, PhD.

Co-author and consulting dentist Dr. Jaana Hurnanen, of the department of forensic medicine at the Hjelt Institute at the University of Helsinki in Finland, took note of the difference between the conditions of the maxillary and mandibular teeth, according to Wade.

"Only the upper teeth have cavities or abscesses, and lots of them; the lower teeth are in fine shape for an ancient Egyptian," Wade wrote on his blog. "Given what we know about the effect of soft, sticky food on the teeth, our thought was that this man was eating something that he could keep isolated on the roof of his mouth. This would keep it off the lower teeth until it was swallowed and leave them in good shape." His theory was perhaps honey or some other soft, sticky, sugary food may have been eaten.

And what about the unusual wear pattern of the incisors? From the 1995 CT scans, it was believed that these teeth had been broken, but the condition of the incisors is consistent with antemortem slow wear of the surface, according to the authors. Since the ancient Egyptians weren't known for modifying the shape of their teeth and the attrition and abrasion wear pattern of ancient Egypt is occlusal in nature, the wear pattern of these incisors is not from mastication, but may be from using the teeth as tools of some sort, they noted.

A work-in-progress facial reconstruction of RM2718. Image courtesy of forensic artist Victoria Lywood.

"The wear pattern doesn't correspond to anything we could find involving the use of the teeth as tools or as an extra hand," Wade wrote on his blog. "I came back to the honey idea, using each of those teeth at various times to remove honey (probably contaminated with wind-blown sand) from a thin spatulate utensil."

What's next for the Redpath mummies?

With the cranial and mandibular skeletal data from the recent CT scans, 3D printing was used to make solid, three-dimensional models, and forensic artist Victoria Lywood is creating facial reconstructions of the Redpath mummies to be displayed at the museum.

Winter Dental Care Tips: Surviving Cold and Flu Season

You probably know by now that good oral health can do a lot more of your body than simply provide you with whiter teeth and a more sparkling smile. But did you realize that it can actually have a bearing on your health in the winter, helping you get through those months where a plague of germs puts you at risk during cold and flu season?

Well, here are some tips to help you survive those common winter bugs, and it starts with your oral health.

1. Replace your toothbrush regularly – a toothbrush that’s not clean can be a source of bacteria and germs as it’s put into the mouth. Replace a toothbrush every four months, whether it appears worn out or not to reduce the spread of germs
2. When you’ve been sick, get a new toothbrush – once you’ve gotten over the cold or flu, you should get a new toothbrush or risk reinfecting yourself every time you clean your teeth
3. Sanitize your toothbrush – any oral health supplies, whether it’s a toothbrush, or tools that help with flossing, can be sanitized. When items are damp, but them in the microwave for one minute to kill bacteria

http://www.universaldentalcenter.com/blog/dental-tips/winter-dental-care-tips-surviving-cold-and-flu-season

How Does a Thyroid Disease Affect Oral Health?

Thyroid conditions make it difficult for the body to produce and regulate a normal amount of very important hormones. This causes a ripple effect that may throw major organs and body systems out of sync. In terms of oral health, the side effects of a thyroid condition may cause serious changes in both the function and health of the tongue, teeth, and gums.

Specifically, thyroid disorders may cause the following conditions (i):

1. Elevated risk of gum disease, heart disease, and stroke.
In general, thyroid conditions may inhibit the body’s ability to heal wounds. This is particularly bad when it comes to oral health, because it makes it easy for the gums to fall into disrepair. Weak or damaged gums are more susceptible to infection than strong and healthy ones, elevating the risk for gum disease among individuals who have a thyroid condition. Elevated risk of gum disease is just the beginning of the story, however.

Individuals with gum disease are also at risk for heart disease and stroke, explains the American Academy of Periodontology (ii). Individuals with gum disease may have a more difficult time warding off oral bacteria compared to individuals with healthy gums. Researchers believe that this makes it easier for oral bacteria to pass through the gums and into the bloodstream. From there, the bacteria attach to fatty plaques and contributes to clot formation.  Additional research has shown that stroke victims are more likely to have an oral infection compared to a control group of individuals who had not suffered from a stroke.

2. Dry mouth (Xerostomia), cavities, and dental caries.
As the name implies, dry mouth occurs when the salivary glands stop producing a normal amount of saliva. Normally, saliva helps to prevent cavities in two big ways. First, it helps to dissolve the foods we eat and prevents stickier food particles, like starches, from clinging to tooth enamel. Second, saliva helps to restore the structural strength of tooth enamel by delivering a continual source of minerals to each tooth in the mouth.

When saliva production is reduced, it becomes easier for food particles to cling to the surfaces of the teeth. Over time, this leads to the cultivation of oral bacteria and tooth decay. Less saliva also means that fewer minerals are delivered to the teeth, making it easier for cavities and dental caries to form in the enamel of each tooth.

3. Enlarged / swollen tongue (Macroglossia).
Thyroid disorders may cause an abnormal swelling of the tongue, which in turn makes it difficult to speak, eat, swallow, and sleep. Of particular concern is the risk this condition poses to the sleep cycle. Individuals with this condition may find it difficult to fall asleep, or they may wake abruptly as the tongue restricts the ability of the body to breath naturally during the night. This condition may contribute to sleep deprivation, a serious sleep disorder that is linked to a number of other conditions like mental fatigue and the early development of Alzheimer’s disease (iii).

4. Distorted sense of taste (Dysgeusia).
A thyroid disorder may also cause the sense of taste to become slowly or abruptly distorted. While non-life threatening, a distorted sense of taste can severely reduce quality of life by decreasing one’s sensitivity to unique flavors or eliminating the sense of taste altogether.

Is There Fluoride in Your Produce?

When thinking about fluoride exposure and its sources, most people think about fluoride in the water supply. But many do not realize that fluoride is also present in the food supply since produce is sprayed with pesticides that contain fluoride.

Fluoride is being added to foods through the use of pesticides that contain fluoride. The most common fluoridated pesticide in the United States is cryolite –a white or colorless mineral made up of fluoride, sodium and aluminum in crystal form. The Environmental Protection Agency currently allows up to 7 parts per million of fluoride on more than 30 fruits and vegetables that are treated with cryolite. They are: apricots, beets, blackberries, broccoli, brussel sprouts, cabbage, cauliflower, citrus fruits, collards, cranberries, cucumbers, eggplants, grapes, kale, lettuce, melons, nectarines, peaches, peppers, plums, pumpkins, radishes, raspberries, squash, strawberries, tomatoes and turnip.

One food in particular, grapes, has long been grown using cryolite, using the trade name Kryocide. It is used to fight against leaf-eating pests. Cryolite is applied as dusts, granulars or powders and is applied by ground or aerial spray. It is mostly used on California grapes, potatoes and citrus. Despite cryolites’ use over the past 50 years, insects have not built up a resistance to it, so it is a fundamental pesticide for many growers.

Because cryolite is easily absorbed into the crops that it is sprayed on, people who eat this produce are ingesting an unknown amount of fluoride. And since wine is made from grapes, it is yet another hidden source of fluoride exposure. According to NaturalNews.com, “Cryolite contains aluminofluoride ions that shed fluoride ions, which then pass through the blood-brain barrier and contaminate brain tissue.”

Two Russian studies, from 1977 and 1969 respectively, show evidence to support that workers exposed to fluoride-contaminated compounds experienced negative affects to their reproductive function. Men working in the cryolite industry for 10 to 25 years and who also had skeletal fluorosis – a bone disease caused by excessive consumption of fluoride —demonstrated a decrease in circulating testosterone.  Women whose jobs heavily exposed them to superphosphates, used mainly as a fertilizer, experienced an increase in menstrual irregularities and genital irritation, as compared to non-exposed women.

It may come as a surprise that fluoride is even present in some organic produce. The National Organic Standards (NOS) allow the use of sodium fluoride in organic agriculture. Even though the NOS states that organic produce growers shall not use “natural poisons such as arsenic or lead salts that have long-term effects and persist in the environment” it still allows the use of fluoride, which is non-degradable and accumulates in humans, soil, plants and wildlife.

One research study found that almost all food contains some amount of fluoride since “plants take it up from the soil and from the air. From the soil, fluoride is transmitted through fine hair rootlets into the stems, and some reaches the leaves.”
Another study that analyzed the typical North American diet found that it dishes out about 1.8 milligrams of fluoride each day, which is almost twice the amount of fluoride delivered from drinking one liter of fluoridated water. When we go the extra mile to seek out organic foods in order to avoid pesticides, we don’t expect to get an extra dose of fluoride.

How Does Fluoride Affect the Pineal Gland?

For much of the 1900s, very little research was conducted to study the effect of fluoride accumulation on brain health. By the 1950s, the subject started to garner attention among a number of scientists, researchers, and dental health professionals. In 1990, a major milestone was reached when Dr. Jennifer Luke asked the question: How does the accumulation of fluoride affect the hard and soft tissues of the body?

Dr. Luke narrowed her study to the effect of fluoride on the Pineal gland, a small organ located in the center of the brain. Specifically, she focused on how fluoride accumulation affects the ability of the Pineal gland to secrete melatonin, a very important chemical that helps to regulate sleeping patterns as well as the onset of puberty.

Is There Fluoride in Your Wine?

Many U.S. wines contain fluoride levels that are too high to allow them to be exported to Europe and other countries that have lower fluoride limits than the United States. These wines often contain as much as six parts per million of fluoride, as compared to the Environmental Protection Agency’s maximum contaminant level for fluoride of four parts per million.

Because fluoride is continuously used on crops and does not biodegrade, it builds up in the soil and is absorbed into plants’ roots, stems, leaves and the fruit. This has most notably been observed in grapes, which have long been grown using cryolite under the trade name Kryocide. It is used to fight against leaf-eating pests. Despite cryolites’ use over the past 50 years, insects have not built up a resistance to it, so it is a fundamental pesticide for many growers.

The chemical company that produces Kryocide, Elf Atochem North America, Inc., released an advisory to U.S. grape growers telling them not to use too much cryolite when growing grapes that were intended for export since they would not meet foreign safety standards. But the company also told these growers to keep using high amounts of cryolite on the grapes grown for domestic use since the U.S. standards for fluoride content are less strict.

A 5-year study conducted on California vineyards in the San Joaquin Valley by researchers at California State University in Fresno found that “multiple applications of cryolite during the growing season significantly increase fluoride in wines.” In grapes grown using cryolite, they found fluoride levels to be between 3 to 6 parts per million and 6 to 9 parts per million, depending on the type of wine. Wines made with grapes grown without the use of cryolite have fluoride ranges from 0.1 to 1.6 parts per million. One glass of wine that has 6 parts per million of fluoride contains more fluoride than one liter of optimally fluoridated water.

During the 1990s, U.S. wines that were exported to Europe were allowed to have up to 3 parts per million of fluoride. This level has since been lowered to 1 part per million. Most European countries do not fluoridate their water, so their safety standards only allow for a much lower limit of fluoride.