Disclosed herein are curable glass ionomer compositions that include a first paste and a second paste, and methods for using the disclosed compositions. The first paste includes water, a polyacid, and a non acid-reactive filler. The second paste includes water and an acid-reactive filler. At least one of the first paste and the second paste further includes substantially crystalline inorganic fibers. In some embodiments, the water content of the first paste and the second paste of the paste/paste GI composition disclosed herein is less than 20% by weight, based on the total weight of the composition.