The answers are below with links to other Chapters.
- How is it that the teeth all tend to grow into the mouth in the correct place?
- What causes the teeth to grow in irregularly?
- Are the teeth always bright white when you are young?
- How many different shapes of teeth are there in the mouth?
- What is the function of the baby teeth?
- Is it important not to loose a baby tooth?
- How is it that when the mouth hinges on the joint the teeth all come together so well?
- How many points of contact do you expect between teeth on the top and the bottom?
- What is it about the position and shape of the teeth that makes you look good, or bad?
- Why do some people hardly get any cavities at all?
Answers about The Ideal Mouth:
- How is it that the teeth all tend to grow into the mouth in the correct place? This is a fascinating and insightful question. In another section will be given more details, but for now suffice it to say that there are normally 52 different teeth, counting primary and secondary (baby and permanent) teeth. The cells from which they develop all start in the same place in the developing fetus, and somehow all migrate to exactly the correct locations in the jaw – 52 different locations. It is one of the great mysteries of living organisms that this happens the way it does. ……………….. BACK to questions
- What causes the teeth to grow in irregularly? While the stem cells which form the teeth know where to go, the bony jaws into which they insert themselves may actually not be large enough to accommodate them. We each inherit parts of our body (and mind) from our parents, but what comes from the father and the mother is not necessarily the best combination. If the mother’s jaws are populated with the father’s teeth, that is cause for crowding perhaps. I can only speculate without knowing this for sure, but it is easy to conceive that some interruption in the fetal development, through the mother’s experiences during pregnancy, may as well lead to placement of tooth-developing cells in wrong locations or orientations…………………BACK to questions
- Are the teeth always bright white when you are young? While they TEND to be, there are situations that disturb this ideal. There are some pathologies that impact the teeth and the appearance of the teeth, even genetic disorders like dentinogenesis imperfecta. While rather unusual these days, but formerly the use of tetracycline antibiotic at an early age caused the permanent teeth to erupt with a greyish-blue color. If you are exposed to too much fluoride in the water or otherwise, the teeth can have a mottled, whitish-grey color. Otherwise, mostly the young teeth are very white – like a white-sand beach, and for much the same reason. Tiny crystals within the teeth scatter the light in all different directions, like fine beach sand, giving the teeth an opaque and bright appearance………………… BACK to questions
- How many different shapes of teeth are there in the mouth? Ideally, there are 52 different shapes of teeth. Now, those on the right are the mirror images of those on the left – so the shapes are the same, just reversed. But there are 20 primary teeth as 10 reversed pairs, and 32 permanent teeth with 16 reversed pairs left and right. ……………….. BACK to questions
- What is the function of the baby teeth? Well – obviously, to chew, once the child has gotten to solid foods. Secondly, less obviously, and more crucially – their function is to guide the permanent teeth into position. The permanent first molars come in BEHIND the back primary tooth, so they are held in position where they should be from front to back. The anterior teeth and adult premolars fit between the roots of the primary teeth, or fit into the resorbing root, so they erupt in exactly the right place, by design anyway. ……………….. BACK to questions
- How important is it not to lose a baby tooth? Let’s just say this, IF a baby, primary, tooth is lost, the space where it was needs to be retained, so that the erupting permanent teeth will have a place to go. This requires the intervention of the dentist. Dentists will even do a kind of modified root canal on the primary teeth to keep them pain-free and in place during the process of permanent tooth eruption………………… BACK to questions
- How is it that when the mouth hinges on the joint the teeth all come together so well? Well – in fact they often don’t, but they are designed to. The closing of the mouth will ideally bring all of the teeth into occlusion (biting contact) simultaneously and with the joint in its most comfortable position at the same time. Even if a persons upper and lower teeth don’t come together in the ideal way – the teeth occluding in positions that the tooth forms were not designed to support – the eruption of the teeth into occlusion will normally occur so that the joint finds its ideal location at the same time. This can be disrupted by the dentist or orthodontist as the occlusal surfaces of the teeth are moved relative to each other, and even the vertical position of the jaws when biting is altered………………… BACK to questions
- How many points of contact do you expect between teeth on the top and the bottom? As is described and illustrated in another section, there may be 8 to10 discrete and distinct points of contact just between an upper and lower first molar. Add in the contacts between the other teeth, and we may have a total of close to 100 contacts! This is for the ideal – where the shapes of the teeth are ideal, and they are all in their ideal locations relative to each other within the arches and between the arches. This is not commonly encountered in nature…………………BACK to questions
- What is it about the position and shape of the teeth that makes you look good, or bad? As they say, beauty is in the eye of the beholder! If you believe that the “movie star smile” is the only way to look attractive, you might want to rethink that. Certainly, there is a “perfect” relationship between your nose, lips, teeth, and gums that is thought of as being attractive, but does it match your personality? Just look at some movie stars – do they all have “perfect” teeth and a “perfect” smile? Those that have the strongest personalities tend to have teeth that match. The “macho” guy may well have teeth that are flattened on the incisal edges (Harrison Ford), in keeping with his intensity. It would not look good for him to have rounded, feminine teeth! The lovely but sensitive woman may have those rounded teeth, but not necessarily in perfect alignment (Keira Knightly). I think the best look is one that is integrated and harmonious – a blend of your personality as perceived by others, and your physical appearance. What do you think?……………….. BACK to questions
- Why do some people hardly get any cavities at all? You might hear people say that their “enamel is hard” – but that is likely not true at all. It IS possible, however, that with fluoridation the enamel is more resistant to the acid produced by decay bacteria than it would be naturally. Other than that it is more about how much acid is produced near the tooth surface and how your body handles it. Of course, if you are in the habit of leaving sugar-rich substances on the tooth surfaces every night as you sleep, acid-producing bacteria will have a feast. But, some people’s saliva is better at eliminating these bacteria than others. We have an immune system component in the saliva called secretory IgA. This immunoglobulin is effective in the elimination of certain bacteria in the mouth, particularly those responsible for decay. Some people have a higher concentration of this IgA than others. Also, the saliva has the ability to neutralize acid – keeping the mouth at a pH which is not damaging to the enamel of the teeth. Some people have better acidity control than others – this is called buffering capacity. This is still a very individualized set of conditions, depending to some extent on heredity. I got my Father’s ability to defend against decay, and have always had decay in my life. My mother had very few fillings in her entire 94 years. My first wife had just a few fillings and our son has had very few. He got lucky, whereas I did not. ……………….. BACK to questions