Decay of Tooth

Dental cavities

No one is or has been spared of this disease or condition (gum problem, dental caries). It is the most prevalent

Chronic disease affecting human beings in every age group. Once it occurs, its effects are seen throughout one’s life. It starts as soon as the teeth erupt in the mouth. Yes, but there are people who do not get caries or decay in their whole life time.

How does it happen?

Dental caries is a sugar dependent disease. Sugar destroys the enamel on the tooth by forming dental plaque that makes holes in the teeth known as cavities.

What causes dental caries?

The enamel of the tooth is made up of inorganic material. There are many theories regarding that:

1. Acidogenic theory:

It states that dental decay is a chemical parasitic process consisting of two stages:

The decalcification of enamel which results in its total destruction in the preliminary stage.

1. This is followed by dissolution of the softened residue. The acid which affects this primary calcification is derived from the fermentation of starches and sugar logged in the retaining centres of the teeth.

There are other theories also which state that the inorganic component of the enamel with some organic material too plays an important role in the carious process. Certain enamel structures made up of this organic material such as enamel lamellae and enamel rod sheaths serve as a pathway for microorganisms through the enamel and the acid produced by these bacteria are capable of destroying the inorganic portion of the enamel resulting in dental decay.

Factors influencing dental decay/caries

1. Tooth
   1. Composition
   2. Size and shape of a tooth
   3. Position

2. Saliva
   1. Composition
   2. pH
   3. Quantity
   4. Viscosity (thick or thin)
   5. Anti-bacterial properties

3. Diet
   1. Nature of diet
   2. Quality of diet
   3. Local factors
   4. Carbohydrate content
   5. Vitamin content
   6. Fluorine content

4. Systemic factors

Heredity
Pregnancy and lactation

THE TOOTH FACTORS

The composition of a tooth:

In relation to the chemical composition of tooth it has been found that the only variation is in the quantity of fluoride.  The fluoride content of the enamel and the dentine of a decayed tooth was far less than a decay free tooth. The surface enamel is more resistant to caries than the sub-surface enamel as it is more highly mineralised. Also, the areas where the water or soil has high fluorine content the people develop flourosis where we see dental and bone deformities. This shows that for a good tooth the fluorine has to be just in the right quantity, neither more nor less.

The size and shape of a tooth:

The only feature which may contribute to the development of dental carries is the presence of deep, narrow occlusal fissures or buccal or lingual pits; for example, fissures on the chewing surface or on the cheek side of the tooth or on the tongue side of the tooth respectively. These fissure hold on to the food, bacteria and debris trapping them. Cavities may develop rapidly in these areas. Likewise on the opposite, if attrition progresses these areas become flattened and less food etc. gets trapped in them and cavities incidence lessens.

The position of tooth/teeth:

The teeth which are misaligned or out of position or rotated or situated at a place not easy to clean and tend to accumulate food and debris are prone to decay.

THE SALIVA FACTOR

Various populations differ in cavities index because of dissimilar diet patterns. In people who have low salivary secretion (salivary gland palsy) or no salivary secretion (xerostomia) suffer from rampant dental cavities. Mild increase or decrease in flow may be of little importance; a total or near total reduction in salivary flow adversely affects dental cavities.

THE DIET FACTOR

We need to do is keep a good oral hygiene, add fibrous food, vegetables.

The nature of food:

• Carbohydrates
• Vitamins

Vitamin A deficiency affects the development of teeth in human beings

Vitamin D is necessary for the normal development of teeth.

Vitamin B complex deficiency may exert a caries-protective influence on the tooth

Vitamin C deficiency produces severe changes in the gums and pulp of the teeth.

• Minerals

The Calcium and Phosphorus dietary intake have a significant role to play in dental caries.

The Fluorine content in a diet is relatively unimportant compared to fluoride in the drinking water because of its metabolic unavailability.

TYPES OF DENTAL CARIES

Dental caries can be of different types. The type of dental caries depends on various factors:

1. Location

2. The rapidity of the spread of a disease

3. Whether it is the new caries or the recurrent caries

An explanation on these is given below for you to understand.

Depending on location

Pit and fissure cavities:

This type of cavity is the first kind or primary kind that develops on the chewing surface of the premolars, molars, on the cheek side and on the tongue or palate side of the upper front teeth. This kind of architecture allows food to get accumulated in it and thus with time develop into decay. Pits and fissures are present in every tooth when they erupt. But with time these usually get obliterated because of wear and tear. These areas become open and allow our oral hygiene measures to clean them.

Caries on the smooth surface of teeth:

This too is one of the first kind or primary kind of caries that develops on the proximal surfaces. For example, the spaces between the two teeth, on near the gingival or gum line on the cheek or tongue or palate side. This kind of cavity is generally seen after the formation of dental plaque. This particular area that is, proximal surface is an area which is not habitually cleaned and this ensures the retention of carbohydrates and micro organisms which subsequently forms acids to start the carious process. 

Caries on the cervical portion of tooth or the neck of the tooth:

This type of caries is found on the cheek side or buckle side, tongue side or lingual side of the tooth. It is a crescent shaped cavity and is directly related to the lack of oral hygiene.

Depending on the rapidity of spread

Acute dental caries:

Dental caries can spread rapidly and involve the heart of the tooth that is, the pulp. This type of caries is also called as acute dental caries. It is commonly seen in children and young adults. The decay makes a small hole in the enamel and reaches the dentine which is comparatively softer part of the tooth than the enamel and then rapidly spreads to the pulp. Another very important type of acute dental caries noted is the Nursing Bottle Caries also known as Baby Bottle Syndrome, Nursing Caries and Bottle Mouth Syndrome: It is a form of rampant caries which affects the deciduous or milk teeth. It is seen developing due to a prolonged use of

1. Breast feeding
2. Nursing bottle containing milk or fruit juice etc.
3. Pacifiers containing sugar or honey

These when used usually as an aid for sleeping at night or nap time may give use to caries. It is usually present in the upper front or maxillary incisors, then spreading to the molars in deciduous teeth. It is fast spreading and widely spreads destruction.

CHRONIC DENTAL CARIES

As the name suggests it is a slow spreading decay process and involves the pulp or the heart of the tooth much later in comparison to acute dental caries.

Depending on the incidence

Recurrent caries:

This kind of caries is seen in areas close to the place where restorations or fillings are done. These are formed if the fillings are not done properly or are not shaped properly in accordance to the contours of the tooth; or if the decay is not removed completely before placing the filling material. Therefore, they collect food particles and make favourable conditions for decay to form and spread.

Arrested caries:

This kind of caries is one which does not grow or show any tendency of spreading or becoming bigger. It occurs in both milk teeth and permanent teeth.¹

SIGNS AND SYMPTOMS OF

DENTAL CAVITIES/DECAY

The cavity starts as a brown or black discoloration on any surface of the tooth, which slowly progresses into a cavity or a hole on the tooth surface.

Initially, symptoms are sensitivity to hot/cold/sweet/sour foods or liquids. If care is not taken decay spreads and reaches the pulp of the tooth and cause pain, swelling, pus formation and fever. When decay starts as described above and any of the initial symptoms are identified by oneself, it is imperative to visit a dentist.

TREATMENT

The dentist will further confirm by different diagnostic methods like visual, tactile and radiographic examination that is, X-rays to access the propagation of the disease and plan the treatment accordingly. If the decay is in the initial stages, a drill with a diamond tipped bur or made of steel is used to remove the diseased portion of the teeth and fill it with cement or silver amalgam or composite or glass ionomer cement. Silver amalgam is still controversial in dental practice from the day it was started. This will be done if and only if the decay has not reached the pulp and infected it. If so, then only a RCT (Root Canal Treatment) can save the tooth.