My Blog Has Moved!

My blog "By Word of Mouth" has been relocated to my dental practice website. Please visit us there at http://www.sharethatsmile.com/.

Sunday, January 30, 2011

FAQ's: Your Child's Teeth



Q.  Dr. Jack, at what age should I first bring my child to the dentist?
A.  It's a good idea to have an oral exam, usually with your physician for convenience, within six months of the eruption of the first tooth, no later than the child's first birthday. Regular visits with the dentist should begin during the third year.

Q.  Why should I be concerned about my daughter's baby teeth when they will be replaced by permanent teeth later?
A.  Even though they are "temporary", the baby teeth serve important functions including speech development, proper nutrition and acting as space maintainers for the permanent teeth.

Q.  We don't drink much tap water, and I don't even know if it's fluoridated. How can I be sure if my child is getting the appropriate levels of fluoride for cavity protection?
A.  Controversy consistently surrounds this subject. Studies have shown that living in a water fluoridated community provides enough exposure from trace sources such as tooth brushing and casual drinking. In a non-fluoridated community, a strict, bottled water situation or the use of a fluoride filtration system, consider administering fluoride tablets or drops prescribed by your pediatrician. You can test the fluoride level of your bottled, tap or well water BEFORE supplements are given. A list of fluoridated towns in Massachusetts is available at www.state.ma.us/dph/bfch/oral/cityfluor.pdf.

Q. What happens if my child gets too much fluoride?
A. The ingestion of huge quantities of fluoride is very harmful, but is highly unlikely to happen. However, moderate excesses of fluoride can result in fluorosis, a patchy white and brown pigmentation of the tooth enamel which can be uncosmetic. That's why you should dispense a pea-size amount of toothpaste which usually contains fluoride. It is felt that young children could ingest much of the toothpaste that they brush which results in a high serum fluoride level. Along with fluoride from the tap and prescriptions, this could cause fluorosis.

Q.  Is it OK to give my child a bottle of milk or juice at naps, or at bedtime to help her fall asleep?
A.  Absolutely not! This practice can cause very destructive cavities called "baby bottle tooth decay". We recommend only water in the bedtime bottle.

Q.  Is teething painful, and what can I do to help?
A.  When babies are teething, usually between the ages of four months and 2 1/2 years, they often have sore and tender gums. Try soothing the pain by gently rubbing the baby's gums with your clean finger or a teething ring. By the way, teething does not cause a fever.  An elevated temperature needs to be addressed as a separate medical concern.

Q.  When should thumbsucking stop?
A.  By the time the permanent front teeth are ready to erupt, generally age 6. Usually, children stop between the ages of two and four years.

Q.  What happens if my child continues to suck his thumb while his permanent teeth come in?
A.  Aggressive and prolonged thumbsucking can actually move the teeth and affect the bite possibly resulting in the need for future orthodontic treatment. 

Q.  What is the best way to introduce my child to his first dental visit?
A.  In our office, we suggest bringing your child along when you get your teeth cleaned. That way he will become familiar with our faces and the office. After your cleaning, we'll give him a ride in the "big" chair and count his teeth. Saturdays are very popular in our office for kids and families. And, we have lots of great stickers and prizes!

FAQ's: Pregnancy and Your Dental Health




Q.  Dr. Share, I'm aware of the changes that my body is going through while being pregnant. Should I have any particular dental concerns at this time?
A.  During pregnancy there is a special need for good oral hygiene, because pregnancy may exaggerate some dental disorders. The old adage  "a tooth is lost for every child"  is untrue.  However, during pregnancy inflammation of the gums may be more pronounced due to a rise in your body's hormonal levels. This is due to the way that your gums react to the irritants in the plaque on your teeth, not the hormones themselves. By maintaining a sound program of brushing and flossing thoroughly twice daily, using an ADA-accepted toothpaste and seeing our hygienist regularly, your tissues will remain their healthiest. 

Q.  Why is prenatal dental care so important?
A.  Firstly, tooth development in the embryo begins as early as the fifth or sixth week of intrauterine life, often even before your pregnancy has been confirmed! And, your eating habits may change, causing changes in your oral health. Your own personal nutrition has a direct bearing on the development of your child's teeth. So, it is important that you receive sufficient amounts of nutrients especially vitamins A, C, and D, protein, calcium and phosphorus. It is also a myth that calcium is lost from the mother's teeth during pregnancy.  The calcium your baby needs is provided by your diet, not by your own teeth.

Q.  Can I have my teeth worked on while I'm pregnant?
A.  The best time for any treatment, especially if you are currently in the midst of dental care, should be discussed with us and your obstetrician. Normally, it's best to schedule necessary visits during the second trimester (the fourth through the sixth months) of your pregnancy. Morning sickness commonly occurs in the first trimester. During the last trimester it may be less comfortable for you to sit in one position for any length of time. Dental cleanings and check-up exams are not only safe during pregnancy but are important to continue. 

Q.  Can I take medications and have anesthetics during pregnancy?
A.  Many medications are perfectly safe and others are a risk to your unborn baby. Taking any medication during pregnancy should be done only on the advice of your physician. Most obstetricians approve the use of local anesthetic (without vasoconstrictors) during pregnancy.

Q.  Are X-rays safe?
A.  Although the amount of radiation from a dental X-ray is minute, the beam is limited to a small region of the face, and we cover our patients with a protective lead apron (pregnant or not), we generally refrain from taking X-rays during pregnancy. If a dental emergency arises mandating an X-ray for diagnosis and treatment, we will thoroughly discuss this with you and your physician.   

Q.  I've been hearing that there might be a link between unhealthy gums, and preterm births and low birth weight babies?
A.  Studies have shown a relationship between periodontal disease and preterm low birth weight babies.  In fact pregnant women with periodontal disease may be seven times more likely to have a baby that's born too early and too small.  The likely culprit is a labor-inducing chemical found in oral bacteria called prostaglandin.  Very high levels of prostaglandin are found in women with severe cases of periodontal diseases.  If the data is correct, this would make periodontal disease responsible for more cases of preterm, low birth weight deliveries than either smoking or alcohol use.

Saturday, January 29, 2011

Incredible Tales of Dental Evolution Part I: The Story of How the Reptilian Jaw Joint Became Our Middle Ear


I am often asked questions about anatomy by my patients, many of whom know about my profound interests in paleontology and evolution. Many of their questions regard their jaw joint called the temporomandibular joint, or simply TMJ. Discussions often lead to the TMJ's interesting proximity to the ear, being directly in front of it. Curiosity usually peaks when discomfort arises within the ear or the TMJ, which can often be difficult to localize for patients when they are in pain. In fact, many patients have their ears examined before suspecting that their pain is arising from their TMJ.

I thought it would be interesting to initiate a series of posts on my blog pertaining to the evolution of various structures relating to dentistry and anatomy. So, let's discuss the evolutionary relationships between middle ear and the TMJ. 

One of my favorite evolutionary transitions is the spectacular modification of the jaw joint for chewing in primitive reptiles and mammals into the middle ear for hearing in modern mammals like us. Yes, you read that correctly! The primitive jaw joint became a part of our middle ear.

A COMMON ANCESTOR
It's important to begin by noting that all mammals (like cats and dogs, lion and tigers, and you and I) share a common ancestor with reptiles (like crocodiles and snakes, and dinosaurs and birds). As you know, mammals have hair, fur and mammary glands, the latter used to nourish their young. But those physical characteristics don't survive when their remains are fossilized. Only the bones and teeth do. Using those fossilized remains, we can trace back in time the relationships of mammals and reptiles to where their lineages converge with a common ancestor. That was about 310-330 million years ago. From that point on, changes gradually occurred through evolution that allow us to distinguish differences between mammals and reptiles. A prime example is our discussion concerning the jaw joint and middle ear.

MOVING FROM A LIFE IN WATER TO A LIFE ON LAND 
In amphibians, reptiles and birds, the eardrum (tympanum) is a circular, thin membrane located behind the jaw joint. Sound is transmitted via the eardrum to the middle ear in the form of vibrations conducted along a small bone called the stirrup (stapes). In primitive amphibians, a bone called the hyomandibula helped to brace the upper jaw against the skull (the suspension-system in all animals is called the suspensorium). In order for our amphibian to fully migrate to land and evolve into a reptile (living and reproducing solely on land), it had to evolve a more sophisticated sound receptor within the middle ear, along with other numerous terrestrial modifications, since air has 3,600 times greater acoustic impedance than water. So, the hyomandibula of the upper jaw  "migrated" through evolution to the middle ear and became the reptilian stapes to enhance auditory reception. But, that wasn't all that was evolving!

THE MIDDLE EAR EVOLVES ALONG WITH THE JAW JOINT
In modern mammals, sound is transmitted from the eardrum to a set of three tiny bones within the middle ear called the auditory ossicles. They are the hammer (malleus), anvil (incus) and stapes (same as the reptilian stapes). 

Here's the Big Question: How did we go from one reptilian, middle ear-ossicle to three in mammals? Primitive reptiles had a jaw joint that consisted of two-bones called a quadrate-articular joint (Q-A). In mammals the Q-A joint was replaced by another two-boned jaw joint called the dentary-squamosal joint (D-S). The D-S is our jaw joint. We refer it as our TMJ or temporomandibular joint. What happened to the reptilian Q-A joint when we evolved  into mammals?

Here's the Big Answer: The primitive quadrate-articular bones of the Q-A joint moved into the middle ear and became the incus and malleus auditory ossicles. That gave us three ossicles in the middle ear, all for improved hearing on land. It also left us with a D-S joint that was more flexible for chewing that the reptilian Q-A joint. Hearing, protection and chewing, as you can imagine, are fundamentally critical traits for survival. More on that later.


A diagram of the human ear showing the ear drum (tympanum)
and the three ossicles of the middle ear
from http://www.kids-ent.com/

Notice the reptilian jaw joint in this crocodile.
It is formed from two bones: the quadrate and articular.
Our croc has only one auditory ossicle, the stapes.

Notice our mammalian jaw joint. It is formed from two bones:
the dentary (also called the mandibular) and squamosal (also called the temporal).
We have three auditory ossicles, the maleus, incus and stapes.


Another way to look at it would be that mammals required better hearing ability on land. They needed three bones in the middle ear, not the reptilian two. So, the reptilian joint (its two bones) migrated to the middle ear in mammals to join the stapes (which was already there).


Legend: (a) Reptilian jaw formed between the quadrate and articular bones,
(b) Mammalian jaw formed between the dentary and squamosal bones,
(c) Reptilian middle ear consisting of only the stapes,
(d) Mammalian middle ear consisting of the incus, maleus and stapes bones,
in which the stapes was the reptilian ossicle, 
and the incus and maleus was the reptilian jaw joint. 
From Addison Wesley Longman, Inc. 1999

The evolutionary and anatomical relationship of our jaw joint to our ear explains why we hear our jaw movements so loudly when we chew, and why our present jaw joint is located so close to our ear. In fact, within our middle ear there are actually tiny muscles and nerves that "belong" to the original jaw bones.    

IT'S ALL ABOUT SURVIVAL
About two hundred million years ago, with their higher rates of metabolism and improved means of locomotion, mammals began expanding into ecological niches far beyond the capacity of reptiles. The mammal's "new" jaw joint provided for a wider range of motion for chewing, and their new-and-improved middle ear provided greater hearing acuity.

These evolutionary changes occurred through the process of natural selection. This is the process in nature whereby only the organisms best adapted to their environment tend to survive and transmit their genetic characteristics in increasing numbers to succeeding generations, while those less adapted tend to be eliminated. Those organisms with greater fitness have a better chance of survival and reproduction. A truly incredible tale of dental evolution!

Thursday, January 27, 2011

FAQ's: Teeth Grinding and Clenching


Q.  Dr. Share, I've been told by my partner that I make noises with my teeth at night while I'm asleep. I can actually see little yellow spots starting to form on the tops of my teeth. Do you think that I'm grinding my teeth in my sleep?
A. The verification of noises and jaw movement by a sleep partner is an excellent indication that you are grinding your teeth. Yellow areas on the biting surfaces of the teeth, especially if they are sensitive, could be the start of wear into the dentin, the softer tooth tissue that lies under the enamel. Keep in mind that dentin can be exposed for other reasons than teeth grinding. Your chewing patterns, type of bite, diet, and even ageing will cause wear, exposing the dentin. So in time, wearing of the teeth is perfectly normal. The big question is whether you’re accelerating the process of wear by grinding your teeth while you are asleep.


Q. If I am grinding my teeth, why am I doing it...I'm not even aware of it?
A.  Grinding or bruxism is extremely common and occurs most often during sleep, when you're least conscious of the movement; however, many individuals clench and grind their teeth during the day. This is considered to be an indication of stress, anger, frustration or anxiety. 

Q.  I've done some googling. It sounds like I have "TMJ." Exactly what does that mean?
A.  The letters TMJ refer to the temporomandibular or jaw joint. They are the hinges that attach the lower jaw to the skull, one on each side directly in front of the ears. It also refers to a complex disorder, with many varied symptoms and many varied names, involving the jaw, jaw joint and the surrounding facial muscles that control chewing and jaw movement.

Q.  I have noticed jaw pain and some facial tightness in the morning when I awaken. I have even noticed tightness in my jaws during the day as well. What might the explanation be for that?
A. Your lower jaw is a curved bone that houses the teeth. It is attached to the skull by muscles, ligaments, and the two temporomandibular joints on each side. From a night of grinding or clenching, the TMJ can become sore and actually feel like an earache, because of its closeness to the ear. The muscles that work the jaw can even ache and become tender from overuse and fatigue. Often, this is at the cheekbone or where the jaw comes to an angle near the neck. Upon awakening the jaw can feel tight and difficult to open due to the tightness of the muscles. This can make the bite feel like it's off. Sometimes a headache will appear at the sides of the head from tight muscles. Also, the joint itself can be a source of popping and grating sounds called crepitus that can also be painful. It's important to mention that pain and aching in the jaws and face may not be accompanied by ear or jaw joint pain. 

Q. How does all this affect the teeth?
A. Years of grinding can cause the teeth to become sensitive as the protective enamel wears down. This exposes the yellow dentin underneath the enamel exposing the nerve endings. Grinding the teeth can be destructive and painful, but clenching, which has no movement, can be painful as well, but wear is not a factor.

Q.  It sounds like I might be a bruxer. How do we confirm my suspicions?
A.  The first step is to schedule an appointment at the office. An examination of your teeth might disclose patterns of wear called facets that indicate habitual use. We also complete an examination of the muscles of the head and neck, and exam your jaw joints for sounds and freedom of movement. In some circumstances an x-ray examination of your TMJ is recommended. The results of the exam along with your history of symptoms may suggest bruxism.  

Q.  What are the treatments for clenching and grinding?
A.  Once a diagnosis has been made, we can suggest various forms of treatment. Several options exist and need to be addressed on an individual basis. At home, a soft diet with no gum-chewing is recommended to rest tired, over-worked muscles and joints.  Analgesics such as Advil or Motrin, if tolerated medically, should alleviate the pain and reduce the inflammation in the muscles and tendons. Slow, careful stretching exercises work well, but try to limit wide opening of the jaw, which includes eating and even yawning. Thermal towel-treatments applied facially can be very soothing. Often bruxism is episodic related to work stress, and family and personal issues. A stress reduction program and regular exercise for healthy relaxation is suggested. Caffeine in the evening is discouraged in order to promote sound sleep. At the professional level, often patients find great relief through stress management. Assuming the stress-induced sleep activity is not short-lived, as from a career change or an imminent wedding, we can provide you with a custom-fitted, plastic mouth guard worn during sleep. This may alleviate or eliminate the painful symptoms and prevent the wear from damaging your teeth. Most patients find that sleeping with a mouth guard will provide dramatic relief.

Wednesday, January 26, 2011

For Dieters, Diabetics and Our Dental Patients: The Commonly Used Sugar Substitutes and Artifical Sweetners



Everyone loves sweets in one form or another. Unfortunately, sucrose ("table sugar") is fattening, promotes tooth decay, increases your blood glucose levels (Glycemic Index) and triggers the insulin reaction. For decades, dieters, diabetics and people concerned about their dental health have sought an alternative to sucrose. Although the perfect solution has not yet been discovered, there are many choices.

The majority of sugar substitutes approved for food use are artificially synthesized compounds. However, some natural sugar substitutes are known, including sorbitol and xylitol, which are found in berries, fruit, vegetables and mushrooms.

The three primary compounds used as sugar substitutes in the United States are saccharin, aspartame and sucralose. In many other countries cyclamate and the herbal sweetener stevia are used extensively.

SACCHARIN (Sweet'N Low) was discovered in 1879 by a scientist with abysmally poor lab technique. He spilled a chemical onto his hand and later touched it to his mouth. Saccharin got a bad reputation in the 1970's when experiments with rats indicated it might be carcinogenic.  Although the FDA attempted to ban saccharin in 1977, Congress issued a moratorium overriding the ban. The moratorium was extended seven times until 1991, when the FDA formally withdrew its proposal.   

CYCLAMATE (Sucaryl) was discovered in 1937 in a similar manner. A grad student who set his cigarette on a lab bench tasted sweetness when he took another drag. Cyclamate widely used both as a table-top sweetener and in foods until it was banned in the US in 1970, but is still in use in other countries. In 1984 the FDA concluded that cyclamate was not carcinogenic, and reversed its decision in 2000.

ASPARTAME was discovered in 1965 by a scientist who licked his finger to grab a sheet a paper. Aspartame (NutraSweet and Equal) quickly replaced saccharin in many foods. Unfortunately, aspartame breaks down at elevated temperatures (it can't be used in cooking), in carbonated beverages and simply over time. Because it is compounded of two amino acids, aspartic acid and phenylalanine (and breaks down into those compounds in the body), persons with the rare inherited disease Phenylketonuria should avoid aspartame. Persons suffering from fibromyalgia may also want to avoid foods containing aspartame and MSG. In addition, there have been reports of possible medical problems associated with aspartame. It has only 4 calories/gram, identical to sugar, but is 200 times its sweetness.

SUCRALOSE is the only non-caloric sweetener actually made from "real" sugar (sucrose). Discovered in 1976 when a student tasted instead of tested, it was granted approval by the FDA in 1998 and appears in little yellow packets on restaurant tables under the brand name "Splenda." Although sucralose is made from sucrose, it is not broken down by the body like sucrose and not used for energy. Research demonstrates that sucralose has no effect on carbohydrate metabolism, blood glucose control or insulin secretion.

TAGATOSE (Nutrilatose) is a naturally occurring sugar that can be found in small quantities in some dairy products. Its use as a low-calorie sweetener was determined in 1981. In the late 1980s Spherix patented an inexpensive process to produce tagatose in bulk from whey, a byproduct of cheese-making. Tagatose has only 40% of the calories of sucrose and is incompletely absorbed during the digestive process, providing the same bulk as sucrose with significantly fewer calories. The FDA has affirmed that tagatose may be used in food products "generally recognized as safe.

The polyols MALITOL, MANNITOL, SORBITOL, XYLITOL and others are naturally occurring sugar-free sweeteners. Although called "sugar alcohols", they are actually carbohydrates. Polyols can be used volume-for-volume like sugar, tend to have a low GI and cause smaller increases in blood glucose and insulin levels than do sugars and other carbohydrates. The FDA classifies some polyols as generally safe, and others are approved as food additives. Research has shown that regularly chewing xylitol sweetened gum actually reduces the incidence of dental decay. It is an ideal sweetener for gum, toothpaste and candies but can cause stomach upset and diarrhea in excess use.


Monday, January 17, 2011

Enjoy a Smile Makeover in Two Visits!



Carol was not only unhappy with the color of her teeth
but the fact that they were uneven and crowded.
 
Carol whitened her teeth and treated herself to a new smile
with beautiful and natural-looking porcelain veneers.

A beautiful smile is the most eye-catching feature of the face. It's probably the first thing that we see when we meet someone! A pleasing smile helps to present a more-positive self image to others. It's calming for us to smile and actually feels good. It's a known fact that the better you look, the more successful you are.

Because of the many advances in dentistry, you no longer have to settle for discolored fillings, unattractive crowns, discolored, stained and pitted teeth, chipped and misshapen teeth, teeth with uneven lengths, and teeth that are crooked and overlapping. Even the most subtle changes in your smile can make a dramatic difference in the way you look and feel about yourself. Many options exist for improving your smile and can often be used together to achieve a total effect. 

The process begins with a private and casual consultation in my office. At that time you will have a chance to tell me, in your own words, what your cosmetic goals are. Some patients are interested in correcting an uncomplimentary tooth that is only slightly turned, and others are interested in a complete makeover. Whether your preference is glamorous or natural, this will give me the opportunity to suggest treatment options to you based on your individual situation and your desires. My practice philosophy is based on my patients being a participant in their own treatment. That can only happen if they are well-informed.

Often the treatment options to improve your smile include bonding or porcelain veneers. Before bonding the teeth, it is often beneficial to whiten them first, and even straighten them with Invisalign. Of course, this is a personal decision, and I will guide you through it. Whatever your preference, please feel free to discuss the treatment options most suitable for you.

Introducing a very happy and beautiful Carol!


Floss To Save Your Life



Suppose that you could prevent a heart attack with a 2-minute, no sweat exercise that could be performed anywhere? Would you be interested? 

Researchers believe that the connection between heart attacks and periodontal disease is so convincing that flossing your teeth regularly might actually be an exercise that saves your life. In fact a recent study showed a 50% increased risk for heart disease in patients with existing periodontal disease.

Plaque, a clear, sticky film that forms on everyone's teeth, is made almost entirely of colonies of bacteria. If the plaque is not consistently removed by brushing and flossing, it will harden into tartar...which then can't be removed by flossing and brushing...only a professional cleaning. Eventually the bacteria may inflame the gums causing gingivitis or progress to a more severe condition of the supporting structures called periodontal disease. At this stage the bone is irreversibly damaged and eventually destroyed, and the teeth may be lost.

If the oral bacteria in a person with gum disease enters the blood stream, tiny clotting cells called platelets clump around the bacteria and can settle on injured tissues such as compromised heart valves and linings, and on damaged blood vessels. A heart attack or a stroke happens when a clot lodges in a coronary artery restricting oxygen flow to the heart muscle or travels to a portion of the brain. In addition mechanisms exist that can accelerate the development of atherosclerosis, hardening of the arteries...the leading cause of death in the world today.

While all the information is not yet available, many clinicians feel that infections do play a role in heart disease, and may explain some of the risk that is not accounted for by other factors including high cholesterol, smoking, diabetes, being overweight, and living a sedentary lifestyle. Preventing gum disease from occurring or treating it early will help save your smile, and may also save your life.

Sunday, January 16, 2011

The Eruption and Shedding of the Teeth


AN EASY TO READ GUIDE TO THE ERUPTION OF THE PRIMARY TEETH

We have two sets of teeth that we acquire during our life. As both sets move from within the jaws from their location of formation to that of function, we say the teeth erupt into place. When the first set of teeth are lost to make room for the permanent teeth, we say that they are shed. The jaws of a child continue to grow, making room for the permanent (adult) teeth that will begin to erupt at about age 6 years. Primary teeth begin to shed between ages 6 and 7 years. This process continues until about age 12 years.

Although hidden from view in the newborn, children generally acquire a full set of primary or baby teeth (also called deciduous because they are eventually shed or milk teeth because they are so white), by the time they are three years old. Adults generally acquire a full set of secondary or adult teeth by age 13 or so, although the third molars or wisdom teeth can slowly erupt throughout early adulthood. Most children have 20 primary teeth, 10 in each of the upper and lower jaws. These teeth are eventually replaced by the permanent teeth, which begin to push through the gums as the permanent teeth are shed.

The primary teeth are temporary but deserve good care. They are of major importance to your child's appearance, chewing ability for digestion, sound nutrition, speech and eventual health of the permanent teeth. The primary teeth hold a place in the jaw for the permanent teeth, which move into place as the primary teeth are shed. If a primary tooth is lost prematurely, the erupting permanent may be prevented from moving into its appropriate position, thereby creating spatial problems that can affect the bite as an adult.

The normal ages of eruption of all the teeth vary greatly from child to child, although the exact sequence in which the teeth erupt does not. Unnecessary concerns should not be created over a tooth that is retained somewhat beyond the norm, unless the adult tooth has been deflected by the baby tooth to the extent that they are both visually present. 

Some children are born with teeth, and others may be twelve months old before the first tooth erupts. Most  primary teeth erupt between the ages of 4 and 12 months. In the majority of cases the first teeth to erupt are the two lower front teeth (incisors) followed by the upper four incisors. Note that the front adult teeth tend to erupt somewhat behind the baby teeth showing two teeth at once, although the canines can be the exception. On the other hand, the adult premolar teeth erupt beneath the roots of the baby molar teeth. The child’s jaws continue to grow, making room for the permanent teeth that will begin to erupt at about age 6 years. Primary teeth begin to shed between ages 6 and 7 years. This process continues until about age 12 years.

You can follow the progression of events on the diagrams. Around age 2-3 years all 20 primary teeth have usually erupted. The last primary teeth are usually lost around age 11-12 years. At age 9 many children will still have primary teeth.  Sometimes permanent teeth have problems erupting or never even form.


THE PRIMARY (BABY) TEETH

THE SECONDARY (ADULT) TEETH

Recognizing the importance of the primary teeth to the child, they should be kept clean and healthy. Supervised oral hygiene by the parent(s), the proper administration of fluorides and routine professional visits to the dental office are highly recommended.