Ds had caps put on his top front teeth (4 of them). Our ped. dentist doesn't use stainless, or "siver", caps. He uses composite. And yes, they're expensive, but I'd be very worried about using stainless in a child's mouth! Children are still developing their immune systems, and the nickel, and the other metals to a lesser extent, can interfere with that. Not to mention that nickel is a fairly common allergen. If your ds seems to be sensitive to chemicals, you don't don't want to expose him, day in and day out until he loses those teeth, to something like that.
As for the IV sedation, goodness! We did choose to give ds some oral sedation. It was a combination of a mild sedative and an antihistimine. It's what our dentist uses routinely for the children in his practice. We asked *a lot* of questions when preparing for the procedure, and he said he hasn't had a child react to it yet (although that doesn't mean it couldn't happen), and it doesn't knock them out (he's very careful about the dose). It just makes them calm, and, more importantly, it makes them not remember the procedure much at all (so they're not afraid of the dentist), and it makes the time seem to pass more quickly for them. We didn't plan to do the sedation at first, but we asked some friends who had gone through the same thing with their dd, and they said they did some dental work without it and some with it, and it went much better with it. And we figured that it was just a one-time deal, and mostly fairly benign stuff. And we crossed our fingers (dh and I are pretty sensitive to chemicals, so we try to be careful with ds). Putting the caps on is pretty extensive. It involves grinding down the teeth so that they're just nubs, then figuring out what size the caps need to be, then mixing the composite and filling the forms with it and putting them on the teeth and "firing" the composites (using a wand with a blue light to harden them). It took at least an hour, probably more (I don't remember exactly) to do 4 of ds's teeth. It was pretty scary for ds, even though he had the sedation. The good part is he doesn't remember it.
Recently, ds needed a filling in one of his molars, and the dentist just drilled and filled it on the spot (again, using composite) without *anything* for the pain. (I know, I know, it sounds like we never brush ds's teeth, but we do, religiously). Ds did fine. Fortunately, I wasn't there, just dh, or I'd have freaked. Anyway, I say this because some things can be done without sedation at all.
Oh, and our dentist allows parents to be present *if* they don't make matters worse. So, we were allowed in, but told that if ds wasn't cooperative that we would have to leave. We didn't have to leave, because we were actually able to help calm him down and keep him calm (not to mention tell the assistant *not* to stroke his head because it was only agitating him). Our friend, OTOH, had to leave (actually, just the mama, not the dad) because she was making things worse just by her presence (she says it's true, the dentist wasn't just making it up). I would find a dentist how has a similar policy. I know it made a difference to ds for us to be there. And be sure and take him in at least once more before the procedure so that he can get familiar with the dentist. Our ds actually looks forward to seeing his dentist!
So, my advice is to find another ped. dentist if possible who has more open policies, and to ask lots of questions, and if need be, push and push to make sure you get what you want. One last thing. It takes practice to do a composite right, so if that's what you want, find a dentist with experience. Also, and this may seem strange, but if your ds is potty trained, you may want to have him wear a diaper or something absorbant that day. Ds is potty trained, and when we took him in recently the dentist used that red dye on his teeth, to see where there was decay, and ds reacted to the dye by peeing in his pants the rest of the day. He just had no control of his bladder. Not to mention, the stress of the event may be a bit much for your ds, and that's not a time to rely on his recent potty training. It may upset him to have a lot of accidents (it did our ds). Obviously each child reacts differently to everything, so you never know, but I figure it's an easy thing to prevent those accidents. Just a thought.
Sorry, no advice on making the enamel stronger. I wish we could figure out why ds keeps having trouble with his teeth! Hopefully someone else will have some.
Good luck, and keep looking out for your ds.
Christie