Can i go to dentist and use dental local anesthesia during my pregnancy?is it safe?

Local infiltration without epinephrine is perfectly fine.

Local anesthesia with "Novacaine" would not spread diffusely and would not affect your pregnancy. Would not choose nitrous oxide, however, as an additive or substitute.

Ask any of the millions of women who have had Rx while pregnant. Safe and effective and considerably less of a risk to our child than infected (cavities) teeth or gums.