Tooth grinding or compressing also removes tooth enamel exposing the underlying dentine. Also, the use of different tooth whitening toothpaste is a significant cause for sensitive teeth. Tooth cavities and fillings make your teeth susceptible by letting the food particles get into the spaces.
In some cases, periodontal diseases cause your gums to leave the teeth, and thus, the tooth surface becomes exposed. The exposed surface lets the food particles (hot, cold, sour, sweet) enter the cavities or roots, causing the pain.