My friend is having an implant done while TTC. They told if she becomes PG it would have to go on hold. You should definitly speak to the dentist and/or doctor before doing it as different anesthetics can affect it.
Just ask for novacaine without epinephrine and, since they do an x-ray halfway through, make sure they are extra careful with the capes. It's much safer once you are into the 2nd trimester. I had my wisdom teeth out at 16 weeks.
Re: Root Canal and Pregnancy
It's best to hold it off, but if it needs done now, do it.