Research has shown how it improves restorative outcomes for over 20 years!
There is research available that demonstrates why warming composite works, from better adaptation to color stability. The following are just a couple of examples.
Greater Degree of Conversion
The Effect of Temperature on composite Polymerization Stress and Degree of Conversion –Fernando C. Calheiros, Marcia Daronch, Frederick A. Rueggeberg, Roberto R.Braga
Clinical significance: Increasing composite temperature allows for reduced exposure duration and lower polymerization stress (both maximum and final) while maintaining or increasing the degree of conversion.
Reduced Shrinkage/ShrinkageStress
Pre-heating of high-viscosity bulk-fill resin composites: Effects on shrinkage force and monomer conversion.Journal of Dentistry – Taubock Tobias T,Tarle Zrinka, Marovic Danijela, Attin Thomas
Clinical significance: Composite pre-heatings significantly reduces shrinkage force formation of high viscosity bulk-fill and conventional resin composites, while maintaining or increasing the degree of monomer conversion, dependent upon the specific composite material used.
Less Micro-Leakage
Effect of pre-heating resin composite on restoration microleakage – Warren C Wagner, Mert N Aksu, Ann-Marie L Neme, Jackson B Linger, Frank E Pink, Stephen Walker
Results: Preheating the composite resulted in significantly less microleakage at the cervical margins compared to the flowable liner and control.
Do preheated composites have less shrinkage?
This experiment was done by Professor Allan Grayson, DDS at NYU College of Dentistry.
Objective: To demonstrate the difference in shrinkage between room temperature and preheated composite.
Steps used in the experiment:
- Cut down anesthetic vials that were sandblasted inside. Bonding agent,(Scotch Bond) applied to the inner glass walls and cured.
- Glass vials maintained in a 940 F water bath.
- A composite, (3M, Filtek Supreme) was placed in the left vial using a Compex HD dispenser at approximately 1550 F (680 C).
- A composite, (3M, Filtek Supreme) was placed in the right vial at room temperature.
- Both specimens were approximately 3 mm thick and cured for 20 seconds with a Valo curing light @ 1,500 mw/cm2
- A Red-Cote disclosing dye was placed in both vials.
Results:
- Note that the red dye did not penetrate the inner circumference of the vial on the left which used a preheated composite.
- Note that the red dye penetrates the inner circumference of the room-temperature composite vial on the right.
Knit Lines and Voids in Dental Fillings by Dr. Richard Price
Dr. Price demonstrates how warmed composites have fewer knit lines and voids than room temperature composite.