According to the National Dental Care Singapore, about 40% of pre-school children in Singapore have visible dental decay. (National Dental Care, 2013)
The combination of food and bacteria causes tooth decay. A clear, sticky substance called plaque that contains bacteria is always found on teeth and gums. As these bacteria feed on the sugars in the food that we eat, the bacteria will form acids which will in the long run destroy tooth enamel, resulting in tooth decay. (WebMD, 2013)
Tooth enamel is like the shell of an egg, the only difference is that it is much tougher. Like an eggshell, tooth enamel protects the softer and more vulnerable part of the tooth. It may seem white, but what you see is actually the layer underneath it, called dentin. Enamel starts as a semi-translucent, but if you consume too much food or drinks with high acidity, it will stain your enamel and make it dingy, yellow or grey. (Alfred, 2013)
As tough as tooth enamel is, it is not completely indestructible. Acids and bacteria from food and drinks will cause erosion and cavities. Bacteria thrives on sugars and will produce high acid levels that corrode the enamel on teeth. This "eating" of enamel that is caused by bacteria and high acid levels will result in enamel erosion. (WebMD, 2013) Because enamel cannot grow back by itself , the damage caused by acids and bacteria is permanent. When tooth enamel is damaged, it will leave the exposed layer underneath, which is dentin, vulnerable to decay.
It has been found out that the more acidic the drink or food, the more our teeth will decay as acids will erode away the enamel on our teeth and cause the inner layer of our tooth to be exposed and without protection. (Alfred, 2013)
Another source has shown that acidic food may be causing wear and tear on our tooth enamel. It is stated that food and drinks with low pH values for example, an apple, will cause a high erosion risk.(Sensodyne, 2013)
1.2 Research Question
An investigation of the effects of the value of pH solution on tooth decay.
Our hypothesis, based on similar studies, is that our teeth will corrode the most when it is exposed to more acidic liquids.
1.31 Independent Variable
The independent variable used in the experiment is the pH value of the solution we soak the eggshells in.
1.32 Dependent Variable
The dependent variable is the change in mass of the eggshell (g) indicating the level of corrosion.
1.33 Constant Variables
The constant variables are the type of eggs used, the temperature of the eggshells and the pH solution, the volume of pH solution in the beakers and the type and size of the beakers.