Recent non-isothermal reaction rate models of light cured resins presented by various researchers do not take into account the increase of the temperature due to the absorption and scattering of light energy within the resin. However, the reaction rate is a strong function of temperature and hence all the calculations performed not adopting this factor are not revealing the true characteristics of the cure process. In this work, the heating effect of the light source is calculated from simple DSC measurements commonly performed after the initial cure of the specimens is recorded. An additional deconvolution procedure of these irradiant heat flow measurements is also presented as well as numerical results from a simple two dimensional model illustrating the differences that result from the inclusion of this parameter in the non-isothermal calculations.