Tooth decay, like any other health issue, should be taken very seriously and treated as soon as it is discovered. The earlier it is discovered, the easier and cheaper it will be to fix. Waiting until it progresses into a later stage will not only be more difficult to fix, it may also be dangerous to your overall health, especially if it gets to the point of infecting your tooth pulp causing an abscess. In this case, you will have to visit an emergency dental clinic to get rid of the abscess which, if not treated properly, can actually be a life threatening infection.
Don’t make the mistake of failing to understand the seriousness of tooth decay. Noticing it in it’s early stages when it has not progress past the tooth enamel can be fixed very easily. Once it progresses into the dentin layer of the tooth, dental intervention will be needed to either put a filling or crown in place to seal the cavity, protecting it from further decay. Progressing into the pulp is where it really starts getting dangerous, and at the very least will require a root canal treatment.