title: Remineralization of eroded enamel lesions by simulated saliva in vitro.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effects of two simulated saliva (SS) remineralization solutions comprising different calcium-inorganic phosphate (Ca/P(i)) ratios on eroded enamel.
  
  
  METHODS
  3 mm diameter enamel cores were extracted from bovine teeth, mounted in acrylic rods, ground and polished,and initially demineralized with either 0.3% (120 minutes) or 1.0% (30 minutes) citric acid solutions (pH 3.8). Both sets of initially eroded specimens were evaluated for surface microhardness (N=10) and treated with either 0.3 or 1.6 Ca/P(i) ratio SS. Groups were first exposed to a seven-day remineralization period and then were cycled in a three-day regimen consisting daily of three rounds of two-hour plus overnight SS treatments and three 10-minute static immersions in demineralization solution. Specimens were assessed using surface microhardness and scanning electron microscopy.
  
  
  RESULTS
  Initial erosion from 0.3% citric acid led to elliptical-shaped pore openings several microns in length and in depth and contrasted significantly with respect to 1% citric acid. The greatest remineralization was observed from the 0.3 Ca/P(i) SS, while the 1.6 Ca/P(i) SS produced the least.
  
  
  CONCLUSIONS
  This study demonstrated the nature of remineralization of eroded enamel depends on both initial erosive conditions and the Ca/P(i) ratio of simulated saliva.
authors.affiliation: RL Karlinsey, Indiana Nanotech, 351 West 10  Street, Suite 309, Indianapolis, Indiana, 46202 USA.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Karlinsey
authors.forename: Allen C
authors.initials: AC
authors.lastname: Mackey
authors.forename: Douglas D
authors.initials: DD
authors.lastname: Blanken
authors.forename: Craig S
authors.initials: CS
authors.lastname: Schwandt
keywords: Citric acid; calcium; microhardness.; phosphate; scanning electron microscopy