* TC=conventionally thermo-polymerized UDMA with 0.5 % (w) benzoyl
peroxide; HTHPI=high-temperature high-pressure polymerized UDMA
with 0.5% (w) benzoyl peroxide; HTHPNI=high-temperature high-pressure
polymerized UDMA with no initiator (mAU stands for milli (10-3) Absorbance Unit)