Decay starts in three places:

1. On the biting surfaces of the teeth.
2. In the gap in between the teeth.
3. Next to the gum line.

Plaque does not have brains, it does not know where to start decay. The reason that decay starts in these three areas is due to a physical situation.

It is important to understand why decay starts in these three areas so that you can prevent it from happening because each of these 3 areas has a different cause and cure, and requires you to do things differently.

Most foods contain some type of sugar or carbohydrate, and over a short period of time they react with bacteria and enzymes found in the mouth, and create lactic acid which in turn erodes the teeth.

In the valley on top of the back teeth there are grooves - we call them fissures. They are weak links in the enamel, and because food is forced into them under great pressure it fuels any bacteria which may be hiding in that groove. This area is too tight for a tooth brush bristle to penetrate, therefore the plaque and bacteria that are in there can cause decay. So we seal the grooves with bonded plastic to prevent food getting in and therefore preventing decay in these areas.

The second place in which decay starts is directly related to areas protected or hidden from the toothbrush bristle. Plaque sticks around the gum line and tooth brush bristles tend to slip over the top of the gum leaving plaque in the 1mm wide zone adjacent to the tooth. As a result of this we see many adult patients with scar lines on their enamel caused by plaque induced acid etching. This creates either white stains or white stains that become brown with time. These are permanent scars in the enamel and represent weak areas which will often turn into decay in later years. Many teenagers have atrocious personal hygiene in their mouth where the plaque is thick around the gums. This causes permanent problems by changing the very nature of their tooth enamel. They pay a life time penalty for those few years of abandoning responsibility and care in cleaning their teeth.

But - by far the most prevalent and insidious area for decay to start, is in the gap between the teeth - because the plaque is well and truly protected, and it is difficult and tedious to clean this area without using floss. Many people have decay in this area which goes undetected for long periods. The result is that the decay continues to eat away at the tooth until it hits the nerve. That is when things get out of hand. The tooth will then require root canal therapy and a crown. Teeth that have root canal therapies tend to be brittle, and have a much higher incident of fractures. Sometimes vertical root fractures occur and the tooth is lost. Also a percentage of root canal therapies don't work and the patient suffers chronic, ongoing tenderness to biting - sometimes with a tendency to flare up into acute abscesses. The tooth may require extraction. You can see what a nightmare can develop from just a small filling, and we see these nightmarish outcomes virtually everyday in some ones mouth. It is far better to avoid all these problems in the first place than to have to deal with them in the years to come.

Also, just by having a large filling, the tooth is significantly weakened, and even though it may not be a problem at the time, twenty years later a crack can develop in the tooth as a direct result, and part of the tooth may fall off. It all stems from the original filling which in turn stemmed from the original decay. So by preventing decay in a tooth you are effectively preventing a series of ongoing repeated repairs, with each one usually more expense than the last.

The problem with decay in between the teeth is that it is very hard to see, and the only way to detect it is by taking an x-ray. In a patient at high risk of decay these x-rays should probably be taken every 18 months to two years. In low risk patients we can reduce the frequency of these x-rays down to once every four to five years. Your risk profile depends on how often you floss, and how often you use strong fluoride, (and/or Topacal) in the gaps (to be discussed later in this literature), where you grow up, and whether there was fluoride in the water and how well trained you are at effective brush removal of plaque. There is a big difference between 2 minutes of random movements with a brush in the mouth and 1 minute of smart, focussed, power-brushing. We can teach you this.

What can I do to prevent decay in these three critical areas?

In the grooves (fissures) on top of your teeth the decay is readily preventable by the use of fissure seals and preventive resin restorations. ( For further information see Patient Education Literature #6 - Fissure Sealants and Preventive Resin Restorations.) Preventive resin restorations are used when we believe there are or maybe small amounts of decay underneath the groove. Fissure sealants basically involve depositing plastic resin on top of the groove and in certain situations may still be an acceptable form of treatment.

However, generally speaking, we tend to clean out the groove where suspicion exists that there may be decayed matter underneath. Unfortunately, with the amount of decay we find even in fluoridated teeth, we are suspicious of all molars. Also, if the groove is cleaned out the plastic restorative material adheres better to the tooth structure and lasts longer - hence a more durable result is obtained. Also the filling material used with a preventive resin restoration is harder, stronger and wears longer. For these reasons, the World Health Organization has stopped recommending fissure seals in favour of preventive resin restorations.

Decay at the gum line gum line

Decay at the gum line gum line is readily prevented by more aggressive brushing techniques. Most patients that have decay at the gum line, simply don't brush hard enough. That does not mean to use a HARD BRUSH - just a SOFT BRUSH with more pressure in it. Be warned, however, not to brush too aggressively or you will wear back your gum.

As far as brushing goes, we walk a tightrope; over brushing leads to wearing back of the gum - under brushing leads to gum disease and decay around the edge.

The warning signs of each are as follows-

Over brushing

1. Small abraded areas on the edge of the gum - essentially looking like gravel rash on the gum, only seen after heavy brushing.
2. The development of slight clefts or valleys at the edge of the gum giving the gum a Y or V shaped look instead of the usual smooth, rounded U shape.
3. The exposing of a yellow part of the tooth where the enamel stops and the root of the tooth begins - caused by the gum being brushed back beyond the edge of the enamel.
4. The tooth looking longer.
5. A sensitive zone at the gum line when it is rubbed with fingernail eg a sharp electric type of pain.

These are classic symptoms of wear back of the gum and although usually caused by over brushing are often associated with fairly good brushing habits over a long period of time. Do not be overly alarmed if your gums are wearing back just a millimetre or so, as this is very common with age, but if your gums are wearing back 2,3 or 4mm you probably have an incorrect brushing technique.

Under brushing

1. Redness in the gum.
2. Bleeding of the gum during brushing.
3. A swollen, puffy appearance to the gum.
4. Tenderness or pain in the gum - characterised more by dull type of pain.
5. When you scratch your fingernail around the edge of the gum line you will pick up a white deposit - this is plaque. This is the cause of the irritation and inflammation in the gum. The bacteria present in the plaque have the unfortunate ability to be able to cause inflammation in the gum, simply by direct contact - there is no need for there to be any cut or crack in order for the gum to become infected.

So, in order to avoid gum line decay use a soft brush such as the Oral B Advantage or an electric brush such as the sonicare. This will effectively remove the plaque from the gum line providing adequate pressure is applied to the brush bristles. Most people don't exert enough pressure - so if you have bleeding gums, plaque around the gums or evidence of decay, it is probably caused by lack of pressure. Use a short vibrating stroke, not a big long sawing stroke as this sawing action tends to cause abrasion and wear back the gums. A short vibrating stroke causes bristle penetration into the crevices under the gums and in the gap between the teeth, without the abrasion. The sonicare does this vibratory style of brushing very well, without any skill on the part of the operator.

Prevention of decay in between the teeth.

This is the most difficult area to prevent decay, however, we have devised a system which seems to work very well. You need to “clean” the gap between the teeth in order to prevent decay in that area. “Cleaning” is a bit nebulous, but really means removing the acid forming plaque. We are not really concerned about getting rid of the food debris (although this is what most people think “cleaning” is). Cleaning the gap means disturbing or removing the plaque. It tends to be a bit tedious and 80% of the population don't (for whatever reason) use floss. If you can use floss on a daily basis, you'll find that you will virtually eliminate decay in between your teeth. Yes, it really is that effective.

The best sort of floss to use is the one that feels comfortable on your fingers and doesn't break. We recommend Johnson & Johnson's Dentotape of Periotape (a Teflon tape) for this reason. It is tape shaped in cross-section (not round) and is far less likely to break as a result. It is also very comfortable to use. A sonicare toothbrush also has the amazing ability to shake up the plaque 3mm ahead of the bristle due to the intense vibration effect it causes. This will reduce the amount of plaque bacteria in between your teeth. It may not be quite as effective as flossing, but it certainly seems to work at reducing gum inflammation in-between the teeth. Extrapolating, it may reduce decay since they are both caused by the same thing - plaque.

The other way to reduce decay is to improve the resistance of the teeth to an acid attack. This can be done by applying strong solutions of fluoride or other re-mineralising agents onto the tooth and allowing the weakened enamel to reform and restore to its former hardness. Most people do not realise this, but decay is a reversible chemical reaction in its early stages. It is not until an actual cavity forms that we really need to do a filling. If we can get to the decay in its early stages when the tooth has just become slightly chalky, we can actually reverse that chalky material back into a hard glassy substance by applying fluorides. Ask you dentist for a strong bottle of fluoride containing 9000ppm fluoride ion - this will usually have a child proof lid on it - if it doesn't - store out of reach of children because swallowing a small amount may be harmful. Fluoride in itself is not dangerous in the right amount, so do not be concerned. There is fluoride in the toothpaste that you use and this is the basis on which some decay is prevented. However there is still an awful lot of decay out there, which is evidence that the amount of fluoride in toothpaste is inadequate to prevent all the decay. The reason why toothpaste only has a small amount of fluoride in it is because children and toddlers will sometimes come across a tube of toothpaste and for reasons best known to them, eat the whole tube! So the amount of fluoride has to be adjusted so that if a child ate the whole tube they would not die. This is essentially compromising the health of adults teeth for the safety of children. If you can successfully keep this stronger material away from children and use it on a regular basis you will find that you get the benefits to your teeth, without risk to the toddlers.

The technique is to apply the fluoride gel to the teeth using either your finger, or a toothbrush, and poke it into the crevices(between the teeth) as much as possible. between the teeth. Then take a piece of floss and floss it through so that the floss picks up the gel already deposited, and smears it over the surfaces of the teeth where they touch together. The primary point at which decay starts in between the teeth is the area just below the contact point. To find that with the floss, simply push the floss gently through the teeth until it pings down and hits the gum, then back up until you encounter resistance. At this point you are just under the contact point between the teeth. Saw the floss around there so that it rubs on either side of the gap and you have effectively treated any area of decay that may be starting between your teeth. If this is all too hard for you, ask the dentist or hygienist to professionally clean your teeth every six months, and you can pay us instead!

The frequency at which you do this is determined by your propensity to get decay. If you are getting a lot of decay we suggest that you brush & floss daily with the strong fluoride gel, and floss it in daily. If you are just getting a small amount of decay, or you have no decay (and wish to make sure that you never do) probably once or twice a week would be adequate. There is no hard and fast rule. If you do get decay in the future you know to increase the frequency.

Once you have flossed with the fluoride you can have a rinse out. Don't be obsessive about rinsing it all out, as the small amount that remains is not going to cause any problems. You can have a tablespoon of this fluoride gel before you will even start to feel any nausea. If for any reason you did swallow too much, you may possibly feel a little bit of nausea - in which case drink some milk and that would neutralise most of the effect of the fluoride. This material is 9000ppm fluoride and toothpaste is only 1000ppm fluoride. Therefore swallowing a small amount of this strong material is the same as swallowing nine times the equivalent of toothpaste.

As was mentioned previously, fluoride is not a toxic element in the right levels. You should know that fluoride occurs naturally in the ground water in certain parts of the world, such as Outback Australia, Colorado and Texas, where it occurs at ~40ppm in the ground water. Kangaroos, Aborigines, Indians and buffalo have been drinking this water for thousands of years without problems. The only side effect is calledHowever sometimes because there is so much fluoride in the water, there is some staining created in their teeth. We call “fluorosis” and it is caused by excessive ingestion of fluoride over long periods of time. There are no reported systemic effects or other health problems other than a mottled or stained look in the enamel. In Sydney we have 1ppm fluoride added to the water so that it is incorporated into children's teeth as they grow, and this gives a life long reduction in the solubility of the enamel and reduces decay by 60% without any other measures being taken! If your child does not live in a fluoridated area or is drinking water filtered with a “reverse osmosis” filter which takes the fluoride out) it is absolutely critical that you administer a fluoride tablet on a daily basis to make sure they get 1mg of fluoride per day.

A new development in the treatment and prevention of decay is known as Topacal. This is a discovery made by Professor Eric Reynolds in Melbourne, who noted that people who have a lot of dairy food have less decay. He successfully isolated the active ingredient which accounted for this drop in decay. It turned out that the enzymes in saliva broke up the protein “casein” in the dairy food into polypeptides, and some of these polypeptides, have the ability to cling to the tooth and concentrate calcium and phosphate onto the surface. They put back into the tooth what has been taken out by the decay acids. This concentrated ingredient is called “Topacal” and can be applied to the teeth in the same way as the fluoride. It is a white paste. Simply smear it on and floss in between the teeth. However, unlike fluoride, you are best to leave this paste on to dissolve to obtain the maximum benefit. Because it is totally non-toxic and there is no reason to rinse out. We suggest you simply put a “pea sized” amount on your finger and smear it onto your teeth, floss if possible, and go to bed. That way it stays around overnight and works more effectively without being washed away so much by the saliva (salivary flow rates decrease at night.)

It is somewhat more expensive than fluoride, but in the end it is much cheaper than fillings, crowns and root canal therapy.

You now know enough to have decay proof teeth. We've done our part in educating you, now its up to you. Please talk to us, if you have any problems implementing this plan of action.

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