Re: 5yo has cavities/what to do besides dentist?
The first thing I would consider is have him checked for Celiac Disease (gluten intolerance). My kids had zero cavities. My daughter, we knew from an early age, to have Celiac so she was off of all gluten and it wasn't a problem. We consider my sons to tolerate gluten just fine.
But, then at ten years old after never having a cavity in his life, my oldest son went in for a regular check up and had 10... TENj! tiny cavities. I almost fainted. I couldn't believe it; in fact, I left that dentist and found another dentist (I was so sure the first guy was just trying to take me for a $$ ride). But, lo and behold he did have 10 cavities. The dentist had no explanation just the usual...maybe he's eating candy secretly at night or dozing off with a mouth full of coke. Well, I'm sorry to say, we just had them fixed and didn't think another thing of it.
Then 12 years later, with deteriorating teeth (at this point we were told he just got the genetically weak teeth from his British side). Anyway, at 22 he started having trouble sleeping, his back would ache when he laid down; it was really weird and it went on for months. He was hardly sleeping.
Then, call it what you want...an intuition...a lightening bolt from above, but I was sitting pondering why his back would only hurt at night and I started thinking "what else is weird about him?" and his teeth came to mind. Then I thought, damn! This could be about calcium and bone deterioration. Frankly, when the thougth stuck me I absoultely KNEW I was right. It was like the thought crossed my mind and God yelled Bingo! I went to the net and started studying Celiac to see what the new information was about it; I had lost touch with new discoveries since my daughter really wasn't affected once she was off of gluten. Anyway, just as I suspected new information proved that Celic can cause osteoporosis or bone & teeth deterioration. I had my son tested he came up positive; we had a bone scan done and indeed, he was already losing bone in the spinal area. We took him off of all gluten-flours and within three weeks all the pain was gone.
I have KICKED myself a million times for not realizing that his sudden, unexplained tooth decay was something I should have persued in great depth; but, as many people know on these forums, docotors and dentists that don't know the answer often throw the old catchall "hereditary weakness" out at us and be believe it.
Maybe your son's tooth decay is something else. But, I would check it out; read up about Celiac Disease; do not just ask your doctor, chances are he knows very little about the myriad symtoms, (many of them "silent") that Celiac causes. It's not that big a deal to be Celiac, you get used to the diet without flour. But, this is a very serious problem if left unchecked; if I hadn't caught it my son would have ended up in a wheel chair and I don't think one doctor in 5 million would have diagnosed tooth decay and a back ache connected, never mind as an allergy to flour.