In vitro wear tests on macro-filled composite restorative materials

Minimum requirements to clinically relevant in vitro tests on macro-filled composites are suggested. Based on literature studies, it is demonstrated that none of the current known tests fulfil these requirements, a fact that probably explains their failing usefulness. Further and, as it appears, more detailed and critical studies are needed. With special emphasis on the abrasion by chewing of food, the maximum surface roughness of the composite as obtained by a specified method as well as the abrasion resistance of the resin matrix proper may be properties worthwhile exploring in future laboratory studies. Laboratory wear testing of micro-filled composites requires methods that in part are specific for this group of materials.