Cavities is the most common problem in Indonesia. The main factor of cavities causes is not giving attention on dental hygiene so it well let germs and bacterium change food remnants be acid. This acid is the cause of cavities.
You are able to handle cavities by using flouride (toothpaste). If it be worse so you can do tooth filling, make a crown on the tooth until root-canal therapy. The worst solution is tooth extraction if tooth filling is impossible being done.
Make sure that you keep your teeth hygiene and consult with the dentist if you get cavities marks.