I'm trying my hand at doing a selective etch technique when using Superb Universal Adhesive, as this is a much talked about technique with many self etch adhesive systems. I'm finding it rather difficult and certainly it is time consuming. Just using Clean and Boost for 20 seconds before Superb or Surpass 2 Primer is much easier, and I suspect more effective. So I'll do a few cases to show you that, even though it can be effective, it's really not a recommended procedure. The idea is because the "universal" bonding systems don't etch enamel really well but they're ok for dentin. Then just place some etchant on the enamel only. Right? (Good luck with that).
It's obvious to me, and should be to you, that "selective etching" is a waste of time and is no more effective (and probably less) than just leaving the Clean and Boost on for 20 seconds. I'm sure it's easier on bigger preps, but it can't be easier than 20 secs of Clean and Boost. Even with the micro-tip on the etchant syringe it was still a mess and got all over the dentin, which is what the procedure is trying to avoid. Now I know there are docs with more skill than I have, but I'm really pretty good at this and possibly even better than some, and I still made a big mess of it. I know that those promoting this procedure won't see this and will continue to show "ideal" procedures. This shows what really happens.