dental caries

what is it

Dental caries (tooth decay) is a multifactorial process. In simple terms, for it to occur three things need to be present: acid producing bacteria (plaque), sugars on which they feed and tooth structure. The acid produced by plaque demineralises tooth enamel, dissolving out calcium and phosphate ions leaving an exposed weak organic matrix which can break off leaving a defect susceptible to bacterial invasion.

If the ions are replaced before the matrix breaks off, the damage is reversed. This is called remineralisation. Saliva contains the right ions for this. It therefore exerts a major influence on the balance between demineralisation and remineralisation of tooth structure. Fluoride on the tooth surface exerts a similar influence. These three ions can only exert their beneficial effect if the mouth has a neutral pH (ie is non acidic).

It follows that if the saliva has a low flow rate (dry mouth) or is of a low pH (acidic), its natural capacity to replace ions and buffer (neutralise) plaque acids is reduced, tipping the balance much more heavily towards demineralisation and caries. In addition the low pH provides the appropriate environment for decay producing organisms to thrive and contributes to non bacterial erosion (loss of tooth structure by dissolution) in its own right. Copious saliva of neutral or alkaline pH tips the balance back towards remineralisation and prevention of caries.

Some people have a higher than usual caries risk, usually because of diet, plaque levels or saliva. There are a number of ways we can tip the balance to greatly reduce caries. Patients need to work together on this with their dentist as the steps taken in the actual dental surgery are only partially effective. Much more long lasting and effective gains are to be made by efforts at home. If you have been diagnosed with a high caries risk, your cooperation is needed to follow the recommended procedures as much as possible.

how can I control it

Identification of high caries risk and following through with a specifically designed caries prevention program is one of the most important things any dentist can do for you. Caries in the adult patient, particularly on hard to reach root surfaces, is irreversibly destructive and frequently cannot be adequately restored. Please give these preventative strategies serious consideration and application. We appreciate there is a lot involved but we think the outcome will be well worth it.

dietary factors

Avoid frequent intake of sugar containing foods, especially sticky foods. Fermentable carbohydrates are what the bacteria like and shortly after eating a meal the plaque pH drops considerably, making this a very dangerous time for your teeth. The longer between meals the more time your saliva has to remineralise any dissolved tooth structure.

plaque reduction factors

Be diligent and accurate with your home oral hygiene. Reduction of the total plaque level in the mouth will involve personal discipline and application. We will work hard to assist you attain and maintain a high level of individual plaque control. Don't brush immediately after a meal as you can brush off demineralized matrix (before breakfast and last thing at night is best).

Chlorhexidine is a proven inhibitor of growth of decay producing organisms. Several gels and mouthwashes are available. Some contain alcohol so if your mucosa is dry and sensitive choose an alcohol free one. One rinse every week is sufficient but it is important to do this after brushing and flossing and after vigorously rinsing all remnants of tooth paste (the fluoride interferes with its action). The safety profile of chlorhexidine is very good as it has limited adverse effects, even with prolonged use. Beware though, it stains teeth if used on a frequent basis. We can advise you as to which chlorhexidine product is best for you.

salivary factors

Ensure adequate water intake to keep the salivary flow rate high. Be aware of work or sports-related dehydration.

Avoid excessive intake of alcohol, caffeine and nicotine, all of which reduce salivary flow. Caffeine is found in coffee, tea, chocolate, cola and soft drinks; nicotine of course comes from smoking but also from certain chewing gums designed to help people give up smoking.

If possible, avoid medications which produce dry mouth (xerostomia) as a side effect. Your doctor will know which medications these are but might not always be able to provide an alternative. Cold and flu medications are common examples of over the counter medications that cause dryness. Alcohol is incorporated in many products to increase their shelf life but it also acts as a drying agent. Alcohol-containing mouthrinses or spray-on products are therefore also included. Most illegal drugs cause a dry mouth.

Stimulate salivary flow with sugar free chewing gum, preferably xylitol containing as studies are showing this product inhibits plaque production.

Alkalinize the saliva with bicarbonate mouthrinses (one teaspoon of sodium bicarbonate "baking soda" in a tumbler of water). Rinse vigorously but don't swallow (accidental ingestion will lead to carbon dioxide in the stomach, gastric distension and discomfort).

Anti-cariogenic preparations: CCP-ACP , a compound found in cow's milk and cheese, prevents demineralization even under severe acid attack. Commercially available products are becoming available, at the moment Recaldent gum and Tooth Mousse are examples. Finishing meals with cheese will also help.

Both salivary flow and pH can be tested clinically.

other chemical tooth protection

Fluoride prevents demineralization and encourages remineralization. Always use a fluoride containing tooth paste. We recommend a very strong neutral pH fluoride toothpaste for use at night when saliva flow is at its lowest. Professional applications of even stronger fluoride can be targeted to especially at risk areas. The amount and type of fluoride prescribed must be considered on an individual level.

If you are taking medications for serious health issues, or if you feel any of the above may interfere with any aspect of your health, you should check with your medical practitioner.

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