METHODS:According to ADA standards, we made two positive metal molds and inserted three metal circular needle at one of mods. Two groups of impressions which named A and B were made.Two groups'marker line were measured and observed by measuring microscope measurements, compare the two groups and the impression of the extent of the law of deformation. Data obtained by analysis of group T test methods.
RESULTS:The deformation of two groups of alginate impressions were 0.38%~0.58% and 0.43%~0.66%,and silicone were 0.38%~0.42% and 0.33%~0.49%. There is no significant difference between the two groups (P> 0.05).
CONCLUSION:It can be used to add markers points which will not affect the impression of the deformation inherent on the oral impression.This marking method is feasible.