twice brushing a day is correct?  

i think brushing three times a day is way better... but follow the advice of your dentist she knows what's best for you...

Here in Jerusalem this is what the school nurses teach. Once in the morning after the breakfast. And just before going to bed

Hmm.. I think it is, because once we eat bacteria increase, and bacteria in our mouth cause plaques and bad teeth, that is why we have to brush after meals.

Morning one should brush well with paste! It is advisable to brush only after every meal/breakfast. The stroke should be for upper teeth downwords and for lower teeth upwards. This method will bring all food particles stuck between teeth and will help maintaining healthy teeth.

Hi,
Any dentist will advise to brush the teeth twice a day.Because they staunchly believe that it is important for good health.Well,it don't take too much time and hence i follow the advise.