Abstract: A restorative dental composite material consists essentially of an organosilicon monomer selected from a class of siloxane materials which are cross-linkable utilizing visible light sensitive photoinitiators, an amount of filler material, a coupling agent and an amount of activator. An amount of ethylenically unsaturated monomer, an amount of thermally pre-polymerized particle material and/or a pigment material can be added to the composite if indicated. The materials exhibit greatly improved properties including a high degree of conversion, minimum water sorption and good color stability.