A comparative study of the effect of four consecutive firing cycles on the marginal fit of all: ceramic crown system and metal ceramic crown system.

The marginal fit of new all ceramic crown system. To know the marginal adaptability of new all ceramic systems. Finesse all ceramic system and traditional metal ceramic system total 15 samples of all ceramic (test group) and 15 samples of metal ceramic crown system (control group) were fabricated and tested for marginal distortion at four firing cycles using image analyzer and special software (Leco Version La 32) in which instead of measuring at points an area was measured that gives a computed mean measured thickness of marginal distortion. Value obtained were evaluated for significance using two tailed, unpaired, student t test and Tukeys-Kramer multiple comparison test. Finesse all ceramic crown system showed continued clinically acceptable marginal distortion through all firing cycles (12.84 μm). Greatest distortion of metal ceramic system occurred during degassing cycle(16.90 μm). In respect of marginal fit all ceramic (finesse) crowns is better choice when esthetics is more concern.