This work presents results of research on compressive strength, microhardness, polymerization shrinkage and water sorption of some specially developed composite materials for dental fillings. The investigated powder fillers were divided into two groups: fluorine-based fillers, such as fluoridated glass, strontium fluoride, ytterbium fluoride and additives of improved mechanical characteristics such as nanosilica and polyethylene. The influence of fluoride ion source on the properties of the composite materials was evaluated. Tests were performed just after the material polymerization and, additionally, after seven, thirty and sixty days. Some small differences between composites were observed.