The wear of human dental enamel against amalgam, Concise composite, SR
-Isosit Inlay/Onlay composite, Vitadur-N glazed porcelain, unglazed IP
S Empress ceramic, and enamel (control) was investigated by use of a m
odified stress cycling machine. Testing was carried out in water and i
n citric acid (pH 4) and the enamel-material couples were subjected to
25,000 cycles of wear with a maximum load of 40 N. Tooth profile redu
ction was measured at baseline and at 5000 cycle intervals with a comp
uter image analysis program. The depth of the wear scars on material s
pecimens was analyzed with a profilometer. All materials produced incr
eased enamel wear in acid. Vitadur-N glazed porcelain was found to be
the most destructive to human dental enamel, and this was closely foll
owed by Empress and enamel.