title: [The comparative study of the effect of silica and calcium carbonate based dentifrice on dentine abrasives in vitro].
abstract: OBJECTIVE
  To evaluate the effect of Silica (SiO(2)) and Calcium Carbonate (CaCO(3)) based dentifrice on their dentine abrasives.
  
  
  METHODS
  Microscope, environmental electron scanning electron microscope (SEM) and radioactive Dentine Abrasion (RDA) assay were used to quantitatively measure the wear of dentine.
  
  
  RESULTS
  The mechanical brushing assay showed severe dentine abrasion with CaCO(3) based dentifrices. There were only minor scratches on the specimens brushed with SiO(2) dentifrices. Analysis of the thin section by SEM after exposure to dentifrices showed that NaF/SiO(2) produced significant remineralization whereas MFP/CaCO(3) system resulted in little remineralization. RDA values were 86.17 and 98.61 for SiO(2) based dentifrices and 222.85 and 253.84 for CaCO(3) based dentifrices, respectively. The morphology of the irregular shaped CaCO(3) with sharp points/edges further explained the brushing and RDA results.
  
  
  CONCLUSIONS
  These results indicate that abrasive in dentifrice, e.g. CaCO(3), can cause severe abrasion of dentine in vitro.
authors.affiliation: Shanghai Research Institute of Stomatology, Ninth People's Hospital, Shanghai Second Medical University, Shanghai 200011, China.
authors.forename: Ming-Yu
authors.initials: MY
authors.lastname: Li
authors.forename: Yi-Tao
authors.initials: YT
authors.lastname: Wang
authors.forename: Jian-Xin
authors.initials: JX
authors.lastname: Yan
authors.forename: Hao
authors.initials: H
authors.lastname: Zheng
authors.forename: Ke
authors.initials: K
authors.lastname: Zhang
mesh_terms: D002119:Calcium Carbonate / Q000009:adverse effects*; D003802:Dentifrices / Q000009:adverse effects* / Q000737:chemistry; D003804:Dentin / Q000473:pathology*; D006801:Humans; D066298:In Vitro Techniques; D012822:Silicon Dioxide / Q000009:adverse effects*; D014072:Tooth Abrasion / Q000139:chemically induced*; D014089:Tooth Remineralization
chemical_list: D003802:Dentifrices; D012822:Silicon Dioxide; D002119:Calcium Carbonate