Question: How many of you perform direct restorations using bulk-fill composites in daily practice?

Question: How many of you perform direct restorations using bulk-fill composites in daily practice?

Dear all, how many of you perform direct restorations using bulk-fill composites in daily practice? If not, what are the reasons? Just to test the confidence of this selective group on this material πŸ˜‰

Eduardo Fernandez: 0

Danilo Biazzetto M. Caldas: I do not, I prefer to wait little bit longer for clinical results.

Jonnie Dixon: I have recently got some 3M Filtek Bulk Fill, not too keen on it so far. I have found good anatomy is more difficult to achieve compared to something like Estelite or Venus Pearl

ClΓ‘udio Fernandes: Hi Victor, its been a pleasure seeing you here. I have used frequently, both low as high viscosity, especially in filling of pulp chamber after endodontics, but always ending sculpture with conventional resins.

Danilo Biazzetto M. Caldas: I have a question about using a thick layer of a low elastic modulus resin under a conventional resin composite. Does low modulus resin support the mitigatory force without deflect? And if it suffer any kind of deflection under a conventional resin would it not cause stress between the conventional resin margin and the tooth?

Flavia Pires Rodrigues: Danilo Biazzetto M. Caldas, A very thin layer will lead to a skrinkage problem and if it is fully bonded as we would like it to be will make the pulpal wall to deflect more than a thicker layer. But the question of how thich is still difficult to guess…See more

Danilo Biazzetto M. Caldas: Thank you Flavia Pires Rodrigues, I agree that the resin layer that is in the base need to have lower elastic modulus to mimic the tooth. But in average the dentin elastic modulus would be around 18-20 MPa. It is much closer to the conventional resin c…See more

Danilo Biazzetto M. Caldas: I am thinking in a mechanical point of view. Under mechanical stress.

Flavia Pires Rodrigues: Still…as if you have a layer that skinks more than the other one it will be under a stress concentration and if you load this scenario it will be worse that a scenario with not that much pre-stress. As stress concentrators are present as I mentioned before, the stress from the loading cycles or any axial test will be distributed in these areas leading to a probable premature failure.

Danilo Biazzetto M. Caldas: So you consider that having a low elastic modulus as a base would cause less stress concentration and consequently when mechanically loaded it would perform better than a resin with a higher modulus and consequent higher stress concentration. Is it what I understood?

Flavia Pires Rodrigues: you asked about the thick layer…so my comments were considering a thich or a thin layer above the high elastic modulus one. I was not considering the higher one alone. But if so, then I would prefer it. Only because the layering would let us having higher shrinkage and more places for stress concentration.

Flavia Pires Rodrigues: Danilo Biazzetto M. Caldas Danilo..I had lower values for the bulk filling ones…around 6 and 7 sometimes…than for the high modulus one you can have up to 24 for Z100 but in average it is what you said for sure.

Flavia Pires Rodrigues: Another issue is the Poisson’s ratio…same elastic modulus but different Poisson’s ratio can make a big difference. Better to have a higher Poisson’s ratio below and a higher above in case of layering.

Danilo Biazzetto M. Caldas: I like your thinking. Speculating with lower poisson’ratio as a base. Would it after long mechanical fatigue to have a kind o work hardening of the resin?

Danilo Biazzetto M. Caldas: Anyway clinically we have more resin fracture when a civ is used as a base, in your opinion would be because of the modulus or the materials interface?

Flavia Pires Rodrigues: I have done some micro -CT of CIV used as the basis and resin on the top and surprisingly it showed a huge amount of bubbles and gaps at the CIV layer…so it was more a problem of handling and giving you no support material as you think. Because of …See more

Danilo Biazzetto M. Caldas: About the poisson’ratio I know it. What i am thinking is, if you have less stress for a specific plastic deformation it would cause crack propagation. Theresult of it is work hardening and decrease the endurace limit what could cause premature frature.

Flavia Pires Rodrigues: A mix of things here… Resins with high modulus are very stiff and they used to show low plastic deformation…same as ceramics that almost have none. These materials usually present high hardness but there is no clear relationship when they are combi…See more

Raul Costa: I use it regularly

Salvatore Sauro: In my opinion it should be still layered as a conventional composite (2mm layers at max)……………….and never light-cured in bulk. But this is just my humble opinion

Flavia Pires Rodrigues: If it was proven that the degree of conversion is the same as the one in the layer and the shrinkage also the same and low as we wish, then it would be actually the best choice due to the the inevitable stress concentration we have between the layers…actually it is a good idea to check that!!

Salvatore Sauro: one more issue is about the heat generated by the polymerisation reaction in 4mm composite…….much higher than when you light-cure 1-2 mm

Danilo Biazzetto M. Caldas:

Danilo Biazzetto M. Caldas: And would take time to dissipate the heat considering that resin is not good doing it.

Flavia Pires Rodrigues: Yes but still it is something that the manufacturer can also control… as the diffusivity is not the same…this is one of the reasons why these bulk ones have been presenting a lot of particles…much more than many non-bulk.

Danilo Biazzetto M. Caldas: Sorry what are made this particle? Ceramic?

Flavia Pires Rodrigues: It depends in the resin. Most of them glass and ceramic.

Marleen Peumans: It is not possible to draw one uniform conclusion about bulk fill composites as this is a very heterogeneous group of materials (regarding composition)! In addition, one has to be careful. I the materials shows an acceptable depth of cure (4mm) in vitro where you have the ideal situation regarding access for polymerization, how to translate this into a clinical situation? Regarding clinical trials, at the moment, only results of short term clinical trials (max. 3 yrs) are available. Long term clinical trials are needed.!There are some indications to use bulk-fill materials, although according to my opinion they cannot replace the conventional composites at this moment.

Victor Feitosa: Indeed Marleen. I agree that the bulk fill resins are very heterogeneous, so as the conventional composites. As Salvatore posted before, there is still very high shrinkage composites available in the market. And from a big company πŸ˜‰

Salvatore Sauro: how many M has this company ?

Victor Feitosa: Hahahahaha

Lucas Zago Naves: I’m old fashioned. Just watching and reading for the moment. Three years (and with that study design) isn’t enough to make me feel safe. I know, maybe I’m being too skeptic… Anyway, I’ll wait a little bit more to use it at my practice.

Lucas Zago Naves: I told you I’m old fashioned!!!!

Lucas Zago Naves:

Lucas Zago Naves: Could be promising. But, we need to go deeper and understand it further. It is an amazing rationale to design a further study.

Leave a Reply

Your email address will not be published. Required fields are marked *