Yesterday when I brushed my teeth I noticed a dark spot on the biting surface of one of my lower back teeth. I have not had any dental care for a lyear due to moving and the need to find a new dentist. I have noticed this area has been sensitive to cold and occasionally when I eat stuff food that are sweet. Could this be a cavity? via email Tuesday May 4, 2010 from Henry.
Hello Henry, thank you for your question. Without examining your mouth and the tooth in question I cannot specifically answer what is going on but I can give you some ideas.
A dark spot on a back tooth (which sounds like you are talking about a molar) could be a cavity. The way to determine this is by a dentist checking it with a dental explorer to see if the area is 'sticky' or 'soft'. If this area is either of the two a cavity can exist. Basically a cavity is breakdown of the enamel tooth structure (the outermost portion of the tooth) or other exposed areas of the tooth (cementum or dentin) due to prolonged increased acidity due to bacterial byproducts. Sensitivity to cold or sweets can signal that their is a deficiency in the enamel-that which protects the internal tooth structures from the oral environment. When enamel is broken down then transmission of cold, hot, sweet can be felt in the pulp of the tooth where the nerve is.
That being said, a dark spot can also exist on the tooth due to staining. If the area is not sticky or soft then simple staining exists which may or may not be able to be removed. The staining can be related to many things like coffee, tea, and consuming othe foods continuously that have 'pigment' to them. They all have the potential to stain if consumed on a regular basis. Usually though staining of a tooth does not cause any type of sensitivity.
I recommend that you see a dentist to have this area examined, as leaving may cause it to progress, become larger and thus more extensive treatment warranted.
Thank you for your question.