My 7 year old daughter has strong white patches in her 2 front teeth which are the permanent teeth. should i be worried?

Have dentist check: White patches can indicate problems with enamel, too much or too little fluoride, breakdown from diet acids..... The list goes on. I would see your dentist as they can determine what the problem is if anything and recommend the right course of action.

Should be OK: Most of the time white patches on newly erupting incisors are areas where the enamel rods in the teeth are bent to reflect light differently. Teeth are probably ok, and at some point in the future your dentist can hide the white spots for you. In the meantime, just to be sure, have your child examined by your dentist to make sure nothing is amiss.

Enamel hypoplasia: This is common when children have a fever during tooth bud development. Have your dentist evaluate and possibly bond over the spots if they are objectionable.