TBU #25: Should I preheat my dental adhesive?
Oct 29, 2022
New issue of The BIOMIMETIC UPRISING
Read Time: 4 min
Dentin bonding has been an interesting topic of debate among dentist since the very beginning of adhesive dentistry. There have been many theories as to what is the best protocols, materials and techniques to use. Biomimetic dentists claim they have put it all together and that they see a dramatic increase in dentin bonding compared to traditional dentistry. I would further back up this argument and say that I'm seeing this first hand. Anyone that has redone an older composite filling will often see the floor of the composite be completely debonded and pop right out when they are prepping the tooth.
We believe in proper caries cleanout, air abrasion, self etching bonding systems, delayed filling of the restoration, among many other steps that improve bonding.
The newest step would be to preheat your bonding system!
In a recent paper from Pascal Magne in 2020, he introduced the idea of mixing bioactive glass to the primer and then heating to 68 degrees Celsius. In the paper he tested the microtensile bond strengths of these groups to different control groups to see the effectiveness and to see if the Bioglass was able to help remineralize the dentin and stabilize the hybrid layer. The tests were done at 1 week and 6 month intervals to see if the bonds were able to be maintained or if there was some bond failures happening.
They found that there was NO decrease in the microtensile bond strength for any of the groups at the 6 month interval. However, what they did find was that preheating the ADHESIVE SYSTEM (total etch system, specifically OptiBond FL) of the primer and bonding resin significantly increased both the 1 week and 6 month intervals. They also found that adding the bioactive glass DID NOT affect the bond strength. Keep in mind that none of these groups reported a decrease in bond strength. So the Bioactive glass was essentially neutral.
One of the main takeaways from the group is that, heating the adhesive system induced primer solvent evaporation and improved the condensation reaction between the silane and bonding agent fillers. This improved the microtensile bond strengths by about 8 mega pascals. This ultimately lead to a microtensile bond strength tested at ~70 MPa. Thats incredible!
The failure modes were also reported to be adhesive failures. If you remember from before, that means the joining or junction between two different structures. This means a failure in the hybrid layer.
It also goes without saying that unidose systems are the preferred and really the only way to do this protocol. Its not advantageous to repeatedly heat the same bottle multiple times.
So for the 1 actionable tip.
1. If you're trying to maximize your bonding potential, get unidose of OptiBond FL and preheat it. There is a 'good enough' reason to do so. You can buy any composite warmer to do the trick.
Bonus tip!
2. Dont stress about bioactive materials just yet. They're not bad. They have some promising potential. They're just not there to be considered a standard yet. However, IMO, there just needs to be more research involved. More research on how to help improve bonding potential, protocols and sequences, and the effectiveness. People like them for pulp capping. Sure if you want. There are other things I like more, but if that's you're preference, then keep with it!
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Side note, I'm all for making Biomimetics more INCLUSIVE rather than so EXCLUSIVE. We should be able to take any material or procedure and adapt it to what system we are limited to and still honor the core biomimetic concepts. That really is my goal for the BSC!
Whenever you're ready, there are 4 other ways I can help you:
1. Work with me 1:1 to grow your biomimetic dental practice.
2. Take one of our online courses that covers this topic in more detail.
3. Join our ever growing community, surround yourself with like-minded biomimetic dentists.
4. Download our 53 page biomimetic protocols guide for posterior direct restorations.
