Growth Behind Two Front Teeth

I have a growth behind my two front teeth. It isn't sore but I do think that it's getting bigger. It is semi-rigid and dome like but there is no pain when I touch it or brush my teeth. Occasionally it does bleed. I have a retainer glued behind my teeth too. I haven't seen a dentist or my orthodontist in over two years but my teeth and gums were given a clean bill of health. I'm just worried that the growth is moving my front teeth now and there is a (very) slight gap forming between the two front teeth. I've seen in previous posts that these sort of growths are benign but should I get it removed or will it eventually stop growing?

Thanks for your help.

[scottma]

Seeing a dentist is advised.