Common Dentistry Interview Questions

Common Dentistry Interview Questions

A very common dental interview question and answer is the one concerning fluoride and fluoridation. Therefore it is wise to have knowledge on fluoride and fluoridation before you attempt to go into your dental interview. Here are some basic facts that you should learn as a minimum in order to answer their questions confidently.

Fluoride is the name of a compound which contains the element fluorine. Fluoride is an extremely effective tool against Dental caries. The effects of fluoride can be systemic or topical.

The Systemic Effects Of Fluoride Are:

If fluoride is ingested during tooth development, there will be an increased number of hydroxyapatite crystals which are substituted by fluorapatite.

Fluorapatite is more resistant to plaque acid than hydroxyapatite so the tooth will be more resistant to Dental caries. This fluoride is ingested in the systemic form through water, fluoride tablets, fluoride drops, salt and milk.

The Topical Effects Of Fluoride Are

It is important to know that tooth enamel undergoes a process of continuous demineralization and remineralisation. When you ingest sugar, the streptococcus mutans bacteria secrete plaque acid which attacks the tooth enamel.

The calcium and phosphate ions move out of the enamel so it becomes weaker. When this process occurs multiple times, the enamel collapses and a cavity develops.

However whenever a sugar attack is over, the saliva acts as a buffer and its buffering capacity causes the calcium and phosphate ions to go back into the enamel and this process is known as remineralisation.

If fluoride is present in the saliva, the calcium and phosphate ions move back into the enamel with fluoride and fluorapatite forms which are more resistant to new attacks.

As already stated above, fluorapatite is more resistant than hydroxyapatite. Evidence also shows that fluoride has an effect on the streptococcus mutans bacteria directly. 

The British Dental Health Foundation is asking the government to increase fluoride availability in water from its current 10% but The National Pure Water Association is opposed on grounds of mass medication and ethical issues. This debate on fluoridation is ongoing.