Depth of cure

A stainless steel mould of diameter 4 mm was placed upon a film, transparent to the LED lamp emission, and then placed on a glass microscope slide. The mould was slightly overfilled with the test material (i.e. Filtek Z250, A3 or Tetric EvoCeram, A3). A second strip of film was placed on the test material surface and another microcope slide was placed on top. To displace excess material, the glass microscope slides were pressed together with the mould and strips of film between them. The assembly was placed upon a filter paper and the upper glass microscope slide was removed. Irradiation with LED lamps was performed according to Table 1. Immediately after irradiation the specimen was removed from the mould and uncured material was removed with a plastic spatula. The cylinder of cured material was measured with a micrometer and the value was divided by two. The test was repeated at least twice.