pregnancy: dental care question?

Ok, so the last time i was at the dentist about a year ago the dentist said that i needed to get my fillings changed as some were coming away and i had started to get 2 or 3 really small cavities, she said i would get my hole mouth numbed and she'd do it all there but she said i don't need to get it done as these won't bother me for about another year or 2, so i refused as she was a training dentist, i didn't trust her advice as i'd never had problems with my teeth before and had seen my now retired dentist 4months before who said everything was ok. so now i've started to get sensitive teeth, feels like cavities sometimes, since i'm pregnant i want to get seen to pretty soon but if the trainee dentist was right, i'd need to get numbed up, which i've never had done before BUT can i be numbed with injection whilst being pregnant? Of course i'd rather not be numbed up but if there is cavities and they're bad i'd need to get numbed up. So is it bad for baby or what?
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The anesthetic is considered fairly safe in pregnancy (about the same dnager as using paracetemol... nicotine in cigarettes is worse). You should wait until your second trimester for your comfort. Your old dentist may not have seen as well, while young dentists may be a little too aggressive. Since fluoride is now used more widely, we've seen a reduction in cavities, however, in some people prone to cavities, we've seen that their cavities are delayed. Where the fillings used to get done be age 13-14, we now see them developing by the mid twenties. I recommend breaking up the fillings in to 2 or more appointments. That way, the dosing of anesthetic is spread out.
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