[Atomic force microscopy and scanning electron microscopic study on the @entity3296 of enamel in XXXX ].

@entity4653 @entity174 @entity3296 @entity2862 @entity35 @entity1388 @entity7034
OBJECTIVE: To investigate the ultrastructure of enamel in the mandibular incisor tooth in a @entity35 model of dental @entity3296 . METHODS: Thirty 5-week-old male and female @entity35 of SD strain were divided into three groups of ten. The animals in the control group were maintained for 8 weeks on pure deionized water, in the low- @entity1388 group deionized water with 22.5 mg/L of @entity2862 (50 mg/L @entity7034 ) was used, and in the high- @entity1388 group deionized water with 45 mg/L of @entity2862 (100 mg/L @entity7034 ) was used. All specimens examined were obtained from the mandibular incisors. Mid-sagittal ground sections were prepared from the direction of incisal point of each incisor for @entity4653 ( @entity4653 ) and atomic force microscopy (AFM). RESULTS: According to the @entity4653 results, the prisms in the control group had a complete and clear column structure with closely packed enamel rods or enamel prisms. The prisms in the high - @entity1388 experimental group were collapsed and showed curved and @entity174 . The level of prism structural changes in the low- @entity1388 experimental group was in between that of the control group and the high- @entity1388 group. AFM for the middle layer enamel showed an average roughness (Ra) of (550.6    32.0) nm in the control group, (415.0    24.2) nm in the low- @entity1388 group, and (194.3    11.3) nm for the high- @entity1388 group. There was significant difference between the high- @entity1388 group and the control group (P < 0.05). CONCLUSIONS: Formation of @entity35 enamel in the high @entity1388 environment presented obvious structural collapse and no clearance between prisms. Such changes appear to indicate a loss of normal prism structure in @entity35 enamels from exposure to high levels of @entity2862 during the maturation period.
