The aim of this study was to synthesize, characterize, and evaluate alternative monomers for use in dentistry. Three siloxane-oxirane low-shrinkage monomers were synthesized, and the products' conversion was followed by Fourier transform-infrared spectroscopy. The products obtained were characterized by H-1 and C-13 NMR and evaluated for viscosity and a refractive index. The polymerization was evaluated by formulating two experimental photoinitiation systems, which varied for the presence of 1,2 ethanediol. A ternary system with camphorquinone (CQ), ethyl 4-dimethylaminobenzoate (EDAB), and diphenyliodonium hexafluorphosphate (DPI) was used as control. The degree of conversion was assessed by differential scanning calorimetry (DSC). The NMR confirmed the synthesis success with 75, 87, and 55% yields for the monomers synthesized. The viscosity and the refractive index of the monomers showed favorable rheological and physical behaviors for application in dentistry. Moreover, the presence of 1,2-ethanediol increased the degree of conversion of the siloxane-oxirane monomers. This study showed a simple and effective way to synthesize siloxane-oxirane monomers with a high potential for application in dental materials. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1728-1733