Toughness is a measure of Energy a material absorbs before it breaks. Strength x strain = ENERGY
Force x distance
Strength is how much force is required to break a sample. This graph is tensile stress vs elongation @ break. Taglus P with elongation @ break = 160%and tensilestress9700psiexhibitsthatitisastrongmaterialtoexherthighorthodonticforcewhichisrequirementofAligners,butonthe opposite side is Taglus Tough which has elongation @ break = 210% with same tensile stress exhibits both properties of strength and toughness which is utmost important property for long terms retainers.
Flexural modulus of elasticity of Taglus Tough is reduced to 260,000 psi which is adjusted in such a manner that it exhibits unique combination of Flexibility and Rigidity making it most comfortable to wear for prolonged use in Retainers.