Has your son started teething yet? Samantha is now seven months old and has her bottom two and one top tooth. The other top one is starting to make it's way down. Now that her teeth have started coming through we don't notice the iregularity in her gums as much. I think if anything the teeth on the swollen side may come through first.
We actually took her to a vascular anomalies clinic that her dermatologist referred her to (Penn State Hershey Medical Center, PA). One of the doctors observing her was a plastic surgeon who specializes in cleft palate so he is very familiar with the structure of the gum and palate. He said that it did not seem very pronounced and felt it was really a wait and see thing while her teeth are coming in. He felt the extra blood supply is causing the overgrowth in her gums. The term they used for this is gingival hypertrophy. She does not have PWS on her gums so she hasn't experienced any bleeding or any discomfort any more than the usual teething pains as far as we can tell. I am still keeping the option open to consult with a pediatric dentist in case there is a problem with her teeth coming in but so far everything seems fine.