When Should My Stitches Dissolve?

I had dental surgery 3 weeks ago (they removed my top wisdom teeth and bottom but had to cut in to my gums and cheek to remove them because they were impacted and embedded, I was under general anesthetic so I have no idea what went on other than I have a mouth full of cotton from my gums and cheeks) they said they used disolvable stitches but 3 weeks later there still there some have come a bit loose and I've trimmed some of them because they keep going in to my throat and making me feel sick and making my throat sore. They said a week to 10 days and they should just fall out but its 3 weeks later now and I still have them in- my doc said he thinks it was just the scab from the surgery but when I looked in my mouth there white (well brown because I smoke and drink coffee) I've tried removing them with scissors, a crochet hook and every thing Heeeelp how can I get em out