I have been trying to whiten my teeth and have bought every kind of toothpaste that says, ‘Whitening’; but none seem to work. Why is this? -J.S. New Jersey
To understand why whitening toothpastes don’t always deliver, we have to understanding the difference between ‘whitening’ and ‘bleaching’…terms that toothpaste manufacturers would prefer that you stayed confused about!
But as we age, the enamel becomes thinner and more transparent, revealing the yellow color of the tooth layer under the enamel, the ‘dentin’, more clearly. To lighten this yellow color, not due to surface grime, a bleaching agent will need to be used (and all surface grime must first be cleaned away to allow it to penetrate the enamel and bleach out the dentin)
Why do my jaws ‘click’? -E.B. New Jersey
The clicking is a result of a jaw joint that has had some wear and tear. In a normal joint as pictured to the left, there is a cartilage disc that separates and cushions the ball and the socket.
Because the jaw joint not only ‘hinges’ like an elbow or a knee, but also ‘slides’ (the only joint the body that does this), the ball of the joint has to be able to slide in the socket. This happens when the disc is pulled forward by a little muscle (called the ‘internal pterygoid’). Then the ball, sitting on the disc like a child sitting on a snow sled, glides forward. In this picture you will notice that the lower teeth now touch the edges of the upper teeth as the jaw has come forward. The muscle is like the friend who pulls the rope attached to the sled.
If this happens over a long period of time the rear lip of the disc gets compressed and it no longer serves to keep the ball centered on it, but rather the ball can now slip off the back of the disc when the jaw opens. This produces a ‘click’ and in early cases when the jaw closes the ball hops back onto the disc and then clicks yet again when the jaw opens again
In your website you describe a replacement for cast gold restorations made with a kind of liquefied porcelain. Is this the same as ‘Cerec’? -M.M., Washington, DC
The technology for restoring teeth with different kinds of porcelain and using different means of fabrication has grown by leaps and bounds in recent years. There are now three widely used technologies for creating tooth replacements out of porcelain: stacking, pressing, and milling.
Stacking refers to taking a porcelain powder, wetting it with distilled water to form a material with the consistency of wet sand, shaping it to the desired shape and then firing it in a kiln so that the porcelain particles fuse to each other to form a solid mass. It is an old technology that has been used to make porcelain fused to metal or porcelain fused to gold crowns for decades. It is also the technique for making highly esthetic porcelain laminates that are used for enhancing the appearance of front teeth. Because porcelain made in this way shrinks as it is fired, it cannot be made to accurately fit anything that is shaped like a hole (an ‘inlay’) as it always has to be ‘overbuilt’ in size to accommodate the expected shrinking. Any shape that sits on a surface (an ‘onlay’, a porcelain laminate, a biting surface) can successfully be built with stacked porcelain and it is the most esthetic material we have. In fact it can be combined with other techniques, although labor intensive to do so, for reasons described below.
Pressing refers to taking a porcelain ingot and melting it under high temperature and pressure and injection molding it into a three dimensional pattern of the missing tooth structure. This technique is explained in more detail elsewhere on this website. It produces restorations that have an extremely accurate fit, but the process involves many steps to accomplish and the varieties of porcelain that are available for pressing is fairly limited. Also, for highly aesthetic requirements it can be cut back to allow an overglazing with stackable porcelain.
Milling is the latest technology. It involves using a computer to create a three dimensional design of a tooth restoration on a computer screen, the data from which is fed into a milling machine that takes a block of porcelain and sculpts it down to the desired shape. When finished it is baked in an oven to harden the structure. This technology has become very popular because it involves many fewer steps then pressing and there are a wider variety of porcelains that are available that can be milled. Lately the most common porcelains to be used are either lithium disilicate or zirconium. Both of these are much harder than enamel and that translates into less breakage, but it also translates into much more wear on the teeth that come into contact with these restorations. Therefore an important step in their fabrication is the highly skilled and labor intensive polishing of the surfaces before they are glazed in the hardening step. Also, for better aesthetics, this material can be cut back to allow an overglazing with stackable porcelain.
Because so much of the work to make a milled porcelain restoration is done on a computer screen, some companies have developed machines different from the ones that they have been selling to dental laboratory technicians that dentists can purchase themselves in order to make these restorations right in their own office. One if these is the Cerec machine. In these circumstances the dentist or, more likely, a trained dental assistant handles the design work ‘while you wait’. It is marketed as a convenience to patients because the restoration is made in a single visit, as nothing has to be sent out to a dental laboratory. But without the oversight of a trained laboratory technician, there is a limit to the refinement that these office made restorations can reach. In regions of high aesthetic need, the skill and artistry of a trained laboratory technician, plus the additional equipment for cutting back and stacking porcelain, will be lacking in typical Cerec restorations. In addition, the polishing step is often avoided by painting a ‘glaze’ over the surface and baked. Studies have shown that this glaze layer wears off in about one year, exposing a microscopically rough underlying surface that can rapidly wear down the opposing teeth.
I want to thank Richard Pavlak, CDT, MDT, FNGS, the founder and director of Porcelain Plus Dental Systems of Cranford, NJ, for his expert help in answering this question.
Are there peer reviewed published studies on the health effects of the mercury vapor released from amalgam fillings? -G., Wantage, NJ
Elsewhere on this website you will find an extensive review of the whole issue of mercury toxicity. In terms of studies in the peer reviewed literature there are many. Here are just a few:
Summers, AO, Wineman, J, Vimy, MF, et al. Mercury released from dental ‘silver’ fillings provokes an increase in mercury and antibiotic-resistant bacteria in oral and intestinal flora of primates. Antimicrob Agents Chemother. 1993;37:825-834.
Siablerud, RL. The relationship between mercury from dental amalgam and mental health. Am J Psychother. 1989;43:575-587.
Lorscheider, FL, Vimy MF, Summers, AO. Mercury exposure from ‘silver’ fillings: emerging evidence questions a traditional dental paradigm. FASEB J. 1995;9:504-508.
Eggleston, et al. Correlation of dental amalgam with mercury in brain tissue. J Prost Dent. 1987; 58(6): 704-707
Vimy, et al. Maternal-fetal distribution of mercury released from dental amalgam fillings. Exper & Molec Pathology. 1990; 52:291-299.
Also, the current issue (September 2015) of the Journal of the American Dental Association includes a cover story on the effects of mercury exposure on US dentists. As all dentists wear gloves while working, the only route for routine exposure is via mercury vapor. The research found that there is a correlation between mercury exposure and hand tremor in dentists:
Anglen, J, Gruninger, E, et al. Occupational mercury exposure in association with prevalence of multiple sclerosis and tremor among US dentists. JADA. 2015: 146 (9): 659-668.
Have you ever seen a correlation between people with autoimmune disorders and dental issues? I’ve started an immunotherapy medication for my Ankylosing Spondylitis and I have 3 cavities out of nowhere!!! Just wondering if these are related to the systemic issues in my body or more likely to the medications? Would love your insight! -S.Y., Santa Rosa, Calif.
I often see correlations between auto immune disorders and dental issues, so you are not alone. The connections are many and they run in all directions:
An auto immune disorder can affect the body’s ability to fight infection or it may affect bone metabolism–this can lead to an increase in tooth decay or gum disease, it can also alter the flow or quality of saliva which has a direct influence on susceptibility to tooth decay particularly along the gum line.
At the same time, dental infections and diseases that are left unchecked can lead to various auto immune disorders. It is not uncommon, as an example, for a patient with severe untreated gum disease to have adult onset diabetes and when the gum disease is treated the diabetes goes away. Years ago I treated a patient who had recently been diagnosed with cardiac arrhythmia. He had not seen a dentist in almost 20 years and needed about 10 teeth extracted as well as other treatment to clean up the rest of his mouth. His arrhythmia vanished when his dental infections were eliminated. In both cases the heavy bacterial load present in the mouth led to high levels of these same bacteria circulating in the blood stream, leading to inflammation of the pancreas in the first case mentioned and in the heart in the second case mentioned.
Lastly, the medications used to treat auto immune disorders, be they non steroidal anti-inflammatory drugs, steroids, or inflammatory protein blocking drugs can each have side effects that can affect dental health. When there is a bacterial infection in the mouth, such as tooth decay or some kinds of gum disease, the body must mount a specific kind of inflammatory response to overcome that infection. If the inflammatory response is being muted by a medication, if will be easier for the bacterial infection to continue on and cause damage–such as tooth decay. The other issue, and this is common, is that oftentimes there is a side effect from medication that reduces the flow of the saliva, and this can have a dramatic effect on tooth decay.
So it is hard to answer your ‘either/or’ question without saying that most likely the answer is ‘and’–all of the above could apply. But we can often narrow down the possibilities on the basis of history. For example, if you have had a long history of being free from tooth decay and if your auto immune condition has been present for a long time then it would be more likely that the recent change in your medication had more to do with the new cavities. But if the medication is helping you then you would be best served by asking your dentist or hygienist for their advice on prevention. This often includes issues of diet, daily oral hygiene, and may require the use of a fluoride mouth rinse. In many holistic circles fluoride has a bad name, and I am not a fan of taking it systemically either in pill form or in treated tap water, but I have no problem recommending it for topical use for my patients who have auto immune disorders or limited flow of saliva.
Can receding gums be reversed? What treatments you use to restore gums? -A., NJ
To properly address the problem of receding gums, it is first necessary to determine the cause in a particular person’s mouth. Gum recession can come about from a number of things and without figuring out why they are receding in the first place, no therapy, including surgically grafting new gum tissue onto the exposed areas, will result in a stable end result. So, Step One is finding out the cause or there may be a combination of causes in a particular area. Step Two is dealing with those causes so that the recession process comes to a halt. Only then, can there be a Step Three–if stopping the progression is not enough then what kind of remediation is possible and/or appropriate?
Gum tissue is largely dependent upon the bone that it sits on top of. If the bone goes away, often times, the gum goes away also. The places where this happens the most is on the upper front teeth, especially the upper canine teeth, but it can happen anywhere. It tends to happen here because the bone can be ‘eggshell thin’ in this region–just covering the upper front teeth with a thin shell of bone. If anything happens to this bone to break it down, the gum tissue recedes. So what can make thin bone disappear? Here are the most common things:
1. Gum disease. This is a bacterial infection of the gums and in its more invasive forms, the infection is not just of the superficial gum tissues (which results in red, puffy, and bleeding gums), but of the deeper parts of the gums that knit into the roots of the teeth and into the bone. If germs get a foothold on these tissues, the bone breaks down and it is often the case that there will be gum recession.
2. Teeth that hit too hard at bad angles to each other (a.k.a. ‘Bite trauma’, a.k.a. ‘Occlusal disease). If a lower front tooth happens to come into contact with the back of an upper front tooth before all the other teeth in the mouth come into contact (while in a jaw position where the back teeth ought to be the ones that hit first), then this upper front tooth will suffer from bite trauma. With repeated hits, this tooth will either move out of the way and look unsightly, or else it will loosen. In either case, the bone over the root on the front of this tooth will suffer from mechanical breakdown and the gum tissue over it will recede. This happens mostly on upper teeth and it can happen to upper back teeth as well. If you go to the place on this website where you can read a selection of my practice newsletters: http://www.centerforintegrativedentistry.com/for-new-patients/practice-news/ and go to the sixth newsletter, “Case 0105MS” you can read more about this cause of recession.
3. Chemical irritants. Certain items/chemicals, held between the gums and the cheek will cause gum recession given enough time. First on this list is chewing tobacco in either loose leaf form or else in the little packets. Also, though less common these days, some people put an aspirin tablet against an aching tooth (it doesn’t help, but the painful irritation of the aspirin, as it burns the gum, makes it feel as if the pain of the tooth is less).
4. Mechanical irritation. Some people brush their teeth with a hard bristled tooth brush and this can abrade and wear down the thin edges of the gums. A word to the wise: dental plaque has about the consistency of cottage cheese. A soft brush should be all you need to clean your teeth; it’s not like trying to get rust off of a car fender!
5. Systemic irritants. Any substance that reduces the blood supply to the very tiny capillaries that nourish the eggshell thin bone will cause that bone to die of asphyxiation. Cigarette smoke contains carbon monoxide, a chemical that binds up oxygen so tightly within the blood that it never makes it to the cells that it should be nourishing. In places where there is just the smallest, little blood supply–such as very thin bone–it’s only a matter of time. Marijuana smoke also has this effect as do recreational drugs that cause constrictions of the blood vessels. These include cocaine and amphetamines. Folks who use those drugs routinely have horrible gums problems.
So, first, which one or which combination of these five problems applies to any particular site of recession. Then the cause has to be eliminated, then the question is, what can be done? Sometimes, as long as the recession has stopped, we don’t have to do anything. Sometimes we cover the exposed root surface with a tooth colored filling, and sometimes there needs to be a visit to a periodontist for gum graft surgery.
I recently had a dental thermogram which revealed an infection (which I was not aware of) on my left lower side. Do you believe in thermogram technology and can it be used to figure out the source of the infection? -B., Doylestown, Pa.
A thermogram is a very useful diagnostic tool. It measures the heat given off by whatever part of the body is imaged. Today’s thermograms can be very precise, particularly when a structure is imaged over set intervals of time, the changes in the ‘heat signature’ of that structure reveal alot about what can be going on there.
In my view, the greatest use of thermograms is in breast imaging, particularly if there is a suspicion of cancer. Cancerous tumors cause blood vessels to grow towards them, and over time a thermogram will reveal ever ‘hotter’ zones where the blood flow has been made to increase.
How can thermograms be useful in dentistry? There are a number of reasons why a structure would image as ‘hot’ that have nothing to do with cancer. In the mouth, cancers are easier to detect visually, and a thermogram wouldn’t be as useful, but here, heat signatures most commonly reflect two different phenomena that also heat tissues up: infection and hyperactive muscles. So, if using a thermogram in dentistry it is most important to use other diagnostic criteria to differentiate between these two as both infection and hyperactive muscles can feel like the same kind of thing.
Recently a patient of mine brought me in a thermogram of her lower jaw, and she was told by the doctor who did the imaging that it showed an infection in the bone. She asked me to evaluate it. I looked as the history of the teeth and gums in this region of her mouth to see if I had, in the past, noticed any problems that could lead to a future infection. Finding none I then went to look at the thermograms that had been taken at different angles of her jaw (head on, side view, and looking upward from under the chin). If the hot spot seen in the side view was from within her jaw bone, it would stay in the same location in each view, but if the hot spot were from a hyperactive muscle, and this patient was a ‘clencher’, then the hot spot would move around more. To visualize what I mean, think of it this way: if I warmed up a little plastic disk and glued it to your cheek and then took the three thermogram views that I mentioned, the front view would show the hot spot far to the outside of the jawbone; the side view would show the hot spot directly over the jaw bone, and the view from below would show the hot spot at a distance away from the jaw bone.
In this way it is possible to differentiate between heat in a tight muscle, or heat in the jaw bone itself. That’s the biggest thing that is often missed, but without knowing a history of the teeth, gums and the jawbone in the imaged area it would still be impossible to be completely accurate with just a thermal image alone. There are tumors that can grow in the jaws, many of which are benign, but they can still register as hot. There can be unusual blood vessel formations, known as ‘A-V malformations’ that can image as hot without there ever being a tumor or an infection.
Still, I am fond of thermograms as a diagnostic tool. It can be the deciding factor in pinpointing which tooth is causing pain when a patient can only point to an ‘area’.