(a) Describe the parts of our tooth with the help of a labelled diagram.
(b) What is meant by dental caries ? How are they caused ?
(c) What is dental plaque ? What harm can it do ? How can the formation of plaque be prevented ?
(a) Describe the parts of our tooth with the help of a labelled diagram.
(b) What is meant by dental caries ? How are they caused ?
(c) What is dental plaque ? What harm can it do ? How can the formation of plaque be prevented ?
(a)
Parts of teeth
Enamel is the material which covers the crown. It is the hardest substance in the body.
Dentine: forms the bulk of the tooth. It is harder than bone but not as much as enamel. It has minute canals through which the run strands of the cytoplasm of the cells in pulp cavity.
Cement: is another bone like structure covering and fixing the root in position.
Pulp: is the soft connective tissue contained in the central space of the tooth.
Crown: the part exposed above the gum.
(b) Dental caries is known as tooth decay or simply, cavity. in this, bacteria change carbohydrate left in teeth to acids. it causes demineralisation of hard tooth structure. If it exceeds, saliva and protein cause tooth decay or cavity. bacterias responsible for this are:- Streptococcus mutans and Lactobacillus.
Many different types of bacteria normally live in the human mouth. They build upon the teeth in a sticky film called plaque. This plaque also contains saliva, bits of food and other natural substances. It forms most easily in certain places. These include:
- Cracks, pits or grooves in the back teeth
- Between teeth
- Around dental fillings or bridgework
- Near the gum line
The bacteria turn sugar and carbohydrates (starches) in the foods we eat into acids. The acids dissolve minerals in the hard enamel that covers the tooth's crown (the part you can see). The enamel erodes or develops pits. They are too small to see at first. But they get larger over time.Acid also can seep through pores in the enamel. This is how decay begins in the softer dentin layer, the main body of the tooth. As the dentin and enamel break down, a cavity is created. If the decay is not removed, bacteria will continue to grow and produce acid that eventually will get into the tooth's inner layer. This contains the soft pulp and sensitive nerve fibres. Tooth roots exposed by receding gums also can develop decay. The root's outer layer, cementum, is not as thick as enamel. Acids from plaque bacteria can dissolve it rapidly.
Symptoms
Early caries may not have any symptoms. Later, when the decay has eaten through the enamel, the teeth may be sensitive to sweet, hot or cold foods or drinks.
(c) Dental plaque is groups of bacterial cells that stick on our teeth along with food particles.
They slowly start destroying our enamel and dentine without our even knowing about it. We realise it when they start destroying our pulp and it causes great pain, but by then a tooth cavity has been formed.
We can stop it by:
1.brushing twice daily.
2)using cotton floss to clean our teeth after every meal.
3)rinsing our teeth regularly.
(a)
Parts of teeth
Enamel is the material which covers the crown. It is the hardest substance in the body.
Dentine: forms the bulk of the tooth. It is harder than bone but not as much as enamel. It has minute canals through which the run strands of the cytoplasm of the cells in pulp cavity.
Cement: is another bone like structure covering and fixing the root in position.
Pulp: is the soft connective tissue contained in the central space of the tooth.
Crown: the part exposed above the gum.
(b) Dental caries is known as tooth decay or simply, cavity. in this, bacteria change carbohydrate left in teeth to acids. it causes demineralisation of hard tooth structure. If it exceeds, saliva and protein cause tooth decay or cavity. bacterias responsible for this are:- Streptococcus mutans and Lactobacillus.
Many different types of bacteria normally live in the human mouth. They build upon the teeth in a sticky film called plaque. This plaque also contains saliva, bits of food and other natural substances. It forms most easily in certain places. These include:
- Cracks, pits or grooves in the back teeth
- Between teeth
- Around dental fillings or bridgework
- Near the gum line
The bacteria turn sugar and carbohydrates (starches) in the foods we eat into acids. The acids dissolve minerals in the hard enamel that covers the tooth's crown (the part you can see). The enamel erodes or develops pits. They are too small to see at first. But they get larger over time.Acid also can seep through pores in the enamel. This is how decay begins in the softer dentin layer, the main body of the tooth. As the dentin and enamel break down, a cavity is created. If the decay is not removed, bacteria will continue to grow and produce acid that eventually will get into the tooth's inner layer. This contains the soft pulp and sensitive nerve fibres. Tooth roots exposed by receding gums also can develop decay. The root's outer layer, cementum, is not as thick as enamel. Acids from plaque bacteria can dissolve it rapidly.
Symptoms
Early caries may not have any symptoms. Later, when the decay has eaten through the enamel, the teeth may be sensitive to sweet, hot or cold foods or drinks.
(c) Dental plaque is groups of bacterial cells that stick on our teeth along with food particles.
They slowly start destroying our enamel and dentine without our even knowing about it. We realise it when they start destroying our pulp and it causes great pain, but by then a tooth cavity has been formed.
We can stop it by:
1.brushing twice daily.
2)using cotton floss to clean our teeth after every meal.
3)rinsing our teeth regularly.
