Cariogenic Bacteria

Many, many years ago..... in a galaxy far, far away.....it was found that bacteria are found within the mouth and that these bacteria produce an acidic bacterial waste products as a by-product of living (yes, they "poop" it out). Unfortunately, it's these acidic waste products that dissolve tooth structure to cause demineralization and caries.

The main, cariogenic bacteria that's involved with the development and progression of dental caries is Streptococcus mutans. S. mutans initially collects on the teeth in plaque and will use fermentable sugars (mainly sucrose – table sugar, glucose and fructose) as a food source. As a by-product of metabolism, an acidic bacterial waste product is created. This acidic waste product will cause a localized decrease in pH, which in turn causes demineralization of the tooth structure.

So, why we tell patient's to brush after meals, three times a day, etc....? It's because if the acidic waste product is not removed or if there is a continuation of acidic waste product production (due to a continuous intake of sugars throughout the day), demineralization and caries is allowed to progress.

The process of demineralization is actually a dynamic process- in fact, demineralization of the tooth structure does occur, but remineralization of the tooth surface occurs as well. If the outer surface of the tooth dissolves (demineralization) for a few hours, remineralize of the surface occurs as the pH returns to normal (due to the buffering capacity of the saliva and the removal of the acids).

Another thing that is truly fascinating are the changes that are seen with respects to aging. As a person ages, caries is more commonly noted on the root surfaces of the teeth. Different bacteria are involved in root caries and the bacteria include Lactobacillus acidophilus, Actinomyces viscosus, Nocardia spp. and S. mutans.

So let's see how things are going so far with this material.....

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Which of the following are required for the development and progression of dental caries?
 
 
 
 

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