Hi. It's a great thought of getting your teeth cleaned and restored of any cavities are there to avoid future dental problems. If you are experiencing sensitivity whilebconsuming hot or cold food... It's probably due to cavities or if you are feeling generalized sensitivity.. It can also be due to enamel erosion due to vigorous or improper brushing technique or accumulation of hard dirt deposit (stains and calculus) on your teeth.
Next Steps
I would advice get a thorough dental check up done... wherein the problem can be diagnosed and accordingly treated
Health Tips
treating small cavities at the starting stage is easier and painless,cheaper and less time consuming. if you leave them unattended.. it might end up in severe pain and the need for a root canal treatment and crown which is a more expensive and time consuming procedure.