Preservation of the Decayed Tooth

Early tooth decay appears as a rough, chalky white mark on the tooth surface, which later becomes a brown stain. This stage is important because early tooth decay can be stopped and further decay prevented, by controlling the frequency of sugar intake in your diet and by avoiding nibbling or snacking or sipping sugary drinks between meals. If the frequent eating of sugar is not controlled, tooth decay will progress, destroying the inner structure of the tooth until the surface layer breaks up to produce a hole or cavity. This is not only visible on examination by a dentist but can be detected, in hidden areas, between the teeth or below the gum or around fillings, by shining a strong light through the tooth or by the use of X-rays.

Regular dental inspections should enable you to have tooth decay detected early, and controlled, without you ever having pain and with simple fillings and minimal damage to the tooth.

Cavities in teeth are repaired by dentists who very accurately remove the destroyed part, shaping and designing the hole to accept a filling. The cleaned-out hole is lined to protect the sensitive inner part of the tooth. Usually, simple fillings are completed with a silver/tin/mercury metal alloy, called dental amalgam, or a white composite material. This is packed into the hole when soft and then sets to produce a hard, durable finish. Some of the white filling materials set hard when exposed to an intense blue light.Metal amalgam fillings are usually placed in back teeth and are dull grey in colour and later blacken, although, if polished, they have a smooth silvery appearance. The material enables the filling to be placed very accurately and can be finely carved and polished. With care, these metal fillings can last a very long time and are strong and wear without undue damage to opposing teeth. Unfortunately, they are not tooth coloured.

Replacing silver fillings with white fillings?

Modern white composites, Have a very good appearance and are chemically bonded to the tooth surface. Unfortunately, those that have a very good appearance wear easily and although they are ideal for front teeth, they are not acceptable as fillings for back teeth which have to withstand the full force of chewing.

Some white composites have been designed for back teeth and are much stronger, although their colour is not quite so natural. There are still problems with them since they tend to wear and abrade opposing teeth or fillings. They are also more difficult to place by the dentist to ensure a perfectly sealed filling. This is because they contract on setting and can pull away from the edges causing leakage and the risk of further decay. In addition, further decay may not easily be detected by the use of X- rays on future dental inspections. Although modern composites are adequate, further research and improvement is required before it could be justified for them to replace metal fillings in back teeth.

Other choices are to replace your silver fillings with a porcelain inlay or crown. These are much stronger than the white fillings, but require two appointments to make.

Are Metal Fillings Safe?

Fears have been expressed that amalgam might be toxic. Despite the enormous number of amalgam fillings placed worldwide for generations, there is insufficient evidence to justify claims that mercury from amalgam fillings have any adverse effects on the health of patients. Even dentists and dental nurses who handle, and are exposed to, the freshly prepared amalgam in its ‘plastic’ state every day throughout their working lives, show little evidence of toxicity.

Amalgam, correctly handled and placed would appear to have a very good track record. Replacement by white composites would not appear to be justified for this reason, particularly as the unnecessary removal of the amalgam would inevitably remove more valuable sound tooth tissue, to be replaced by a material which as yet may not be as long-lasting as amalgam. In Germany recently, there has been a very public debate about the banning of amalgam but it was concluded that set amalgam would appear to be safe, but research should continue to find an alternative material which has not as yet been made.

How long should fillings last?

If a person continues to have a high and frequent intake of sugar and does not clean between teeth, further decay will occur around the filling whichever material is used.If someone eats a healthy diet, regularly brushes with fluoride toothpaste and visits a dentist regularly, tooth decay will be brought under control and the fillings should last many years.Wear will occur if the material is unavoidably put in a position which stresses it beyond its limit, fracture may occur, or the surrounding tooth structure may fracture. This usually happens in large cavities and hence the importance of prevention and regular inspections to permit early detection and repair.

Advanced Techniques

If a large amount of tooth tissue has been destroyed or damaged, more expensive materials and time-consuming techniques are required to restore the tooth. Such destruction of the tooth should not be accepted as inevitable or unavoidable since, with care, a tooth can survive the lifespan of the individual into old age and increasingly, many elderly people are showing this to be possible.Once tooth structure has been destroyed, the body cannot restore it and that part is lost forever. Even with the best efforts of the dentist, using very sophisticated techniques and materials, any repair is never as sound as the original tooth. It is important for people to take the responsibility to look after their teeth, to preserve their appearance, comfort and general health.

Tooth Decay

Advanced tooth decay appears as a dark brown or black mark or hole in the tooth. At this stage, pain may not be felt but treatment should be carried out at the earliest opportunity. Delay will ultimately result in pain which may be difficult to control and the repair of the tooth will be much more difficult, expensive and time-consuming.

Such decay can be prevented:

  1. By controlling the frequent eating of excessive amounts of sugar in your diet and by avoiding nibbling or snacking or the sipping of sugary drinks between meals.
  2. By careful tooth brushing with a fluoride toothpaste daily
  3. By visiting your dentist for regular check-ups to have tooth decay detected early, and controlled, with simple fillings and minimal damage to the tooth.


Accidental damage to front teeth can often result in a large defect but again should not be regarded as unavoidable. Often unsupervised, the boisterous behaviour of children are accidents waiting to happen and although it is impossible to control entirely such accidents are avoidable. Young adults involved in contact sports such as rugby can reduce the risk of accidental damage by the wearing of gum shields.

Many people use their teeth as tools to open bottles, cut thread or string or against hard unyielding objects. Such misuse can easily chip the outer structure of the tooth and is easily prevented. It may be less convenient but it is safer and ultimately less expensive and uncomfortable to use the correct instrument for the job, not your teeth.


Sometimes the whole structure of the teeth can be severely stained by certain chemicals in the bloodstream when the teeth are developing in the child’s mouth. The antibiotic, tetracycline, was found to cause severe staining and is now rarely used. The excessive intake of fluoride can cause visible mottling which should be prevented. If you wish to give your child fluoride tablets to prevent tooth decay please ask your dentist about the correct dosage for your child.

Tooth Wear

Excessive tooth wear can occur as the result of habitually grinding the teeth together, using abrasive kinds of toothpaste with an aggressive brushing technique or the excessive intake of acidic foods or drinks such as citrus fruit (oranges, lemons, pineapples). Such tooth wear can be prevented or reduced.

The more advanced techniques of repairing or replacing tooth structure are: Veneers, bleaching, crowns, bridges, dentures and implants.

Veneers are thin layers of porcelain (looking a bit like false fingernails), which are glued to the front surface of the tooth. This technique is often used where the tooth is more or less intact but can be used to disguise stains and marks, chipped or cracked teeth, unwanted spaces or misshapen teeth. Although a little of the front surface of the tooth has to be drilled away, the preparation for a veneer is far less destructive than that required for a crown.

Bleaching. A bleaching solution can be applied to the outside surface of the tooth or, if the tooth is bad and darkened internally, to the inner part of the tooth. It can be time-consuming and may have to be repeated from’-time to time. In addition, existing white fillings may have to be replaced to match the new bleached shade.

Crowns. If loss of tooth structure is excessive, crowning or “capping” of the tooth might be required. Gold crowns are sometimes used for back teeth and porcelain or metal bonded with a porcelain facing are usually used for front teeth. If the tooth is dead or of the root alone is left, the remaining root has to be root-filled, a metal post is then cemented into the root, and a crown is cemented onto the post. It is not surprising that such complicated, skilful work using precious metals and laboratory facilities is expensive.

Bridges and Dentures. A missing tooth or teeth can be replaced with a denture, which can be removed from the mouth, or a bridge, which is fixed to the teeth on either side of the gap. Bridges are either adhesive bridges or conventional bridges.

The adhesive bridge consists of a crown, to replace the missing tooth, with little metal wings which are cemented onto the back of the teeth on either side of the gap. The advantage is that very little drilling, if any, is required. If you don’t wish to have a silver coloured metal wing, they can be done in gold or even tooth coloured porcelain.

The conventional bridge requires teeth, usually on either side of the gap to be crowned with the false tooth joined to them. More tooth structure is drilled away to prepare a conventional bridge.

Anyone who has veneers, crowns, bridges or dentures will require special cleaning techniques and instruments to thoroughly clean around the complex shapes and irregularities.