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Sugar and Teeth

Sugar, saliva, and bacteria lead to a formidable combination that may lead to tooth decay. After eating sugar, particularly sucrose, and even within minutes of brushing your teeth, sticky glycoproteins (combination of carbohydrate and protein molecule) adhere to the teeth to start the formation of plaque. At the same time millions of bacteria known as Streptococcus mutans also adhere to the glycoprotein. Although, many oral bacteria also adhere, only the S. mutans is able to cause cavities. 

Introduction

In the next stage, the bacteria use the fructose in a metabolism process of glycolysis to get energy. The end product of glycolysis under anaerobic conditions is lactic acid. The lactic acid creates extra acidity to decrease the pH to the extent of dissolving the calcium phosphate in the tooth enamel leading to the start of a cavity. Preventative measures include frequent brushing and flossing to prevent plaque build up. A diet rich in calcium and fluoride in the water lead to stronger tooth enamel. A diet of more complex carbon hydrates that are low in sugar and no sucrose snacks between meals is also a good preventative measure.

546Hsucrose.gif

Only the S. mutans bacteria has an enzyme called glucosyl transferase on its surface that is able to cause the polymerization of glucose on the sucrose with the release of the fructose. The same enzyme continues to add many glucose molecules to each other to form dextran which is very similar in structure to amylose in starch. The dextran along with the bacteria adheres tightly to the tooth enamel and leads to the formation of plaque. This is just the first phase of cavity formation.

The graphic below shows only a portion of this process which shows the release of the fructose. The glucose undergoes further polymerization as stated above.

546sucrosehydrol.gif

Glycolysis

In the next stage, the bacteria use the fructose in a metabolism process of glycolysis to get energy. The end product of glycolysis under anaerobic conditions is lactic acid. The lactic acid creates extra acidity to decrease the pH to the extent of dissolving the calcium phosphate in the tooth enamel leading to the start of a cavity.

Preventative measures include frequent brushing and flossing to prevent plaque build up. A diet rich in calcium and fluoride in the water lead to stronger tooth enamel. A diet of more complex carbon hydrates that are low in sugar and no sucrose snacks between meals is also a good preventative measure.

548fructose-lactic.gif

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