Selective Etch Technique or Clean and Boost- By Thomas W. Mitchell, DDS, FAGD

Introduction: 

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).

Thomas W. Mitchell, DDS, FAGD
This is the first time I tried it using the standard tip on the etchant syringe. What a mess!
Thomas W. Mitchell, DDS, FAGD
The enamel of course is nicely etched, and of course so is the dentin. I'll try again on another case using a smaller tip on the syringe. So I decided to use a micro-tip on the HPO3 syringe to see if I can control it better. I practiced extruding the etchant so I could push out a nice thin line instead of a lump. So here goes:
Thomas W. Mitchell, DDS, FAGD
#29 with distal decay thru the enamel.
Thomas W. Mitchell, DDS, FAGD
A simple quick prep.
Thomas W. Mitchell, DDS, FAGD
This is a Garrison silver "bean-shaped" matrix with the Garrison orange "maximum adaptation Soft Face" ring. I did not need a wedge to close the gingival margin. You can see how much difficulty I had controlling the etchant, even with the micro-tip on the syringe. Before I placed the etchant I quickly cleaned the prep with Clean and Boost. That took me just a few seconds. Applying the etchant took me about a minute.
Thomas W. Mitchell, DDS, FAGD
This is after washing off the etchant, drying the surface, applying Bondsaver D, leaving the surface damp, applying 3 coats of Superb Universal Adhesive, air thinning that, applying a layer of Titan Flowable composite shade A-2 and co-curing the Superb and the Titan for 3 seconds with the VALO light set on "XTRA POWER" (3200 mW/cm2) aka "plasma setting".
Thomas W. Mitchell, DDS, FAGD
I bulk filled the prep with Exquisite Restoration composite, condensing and shaping with composite instruments and Seamfree wetting resin, then cured it for 3 seconds with the VALO on "plasma setting".
Thomas W. Mitchell, DDS, FAGD
Finishing was very simple using Softflex discs and Brasseler polishing diamonds from the kit Dr. John Kanca designed. Then I glazed/sealed it with another thin layer of Superb Universal Adhesive and did the final cures for 3 seconds from each direction.

Conclusion: 

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.

Case by: 

Thomas W. Mitchell, DDS, FAGD

Email: 

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