title: Mode of action studies on the formation of enamel minerals from a novel toothpaste containing calcium silicate and sodium phosphate salts.
abstract: OBJECTIVE
  To investigate in vitro and in situ the deposition and formation of hydroxyapatite (HAP) on enamel surfaces following brushing with a novel toothpaste containing calcium silicate (CaSi), sodium phosphate salts and fluoride.
  
  
  METHODS
  Polished enamel blocks were brushed in vitro with a slurry of the CaSi toothpaste. After one brush and four weeks simulated brushing the enamel surfaces were analysed. In an in situ protocol, enamel blocks were attached to first or second molar teeth of healthy subjects, exposed to 4 weeks twice per day brushing with the CaSi toothpaste and then analysed. The surface deposits were analysed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). In addition, the CaSi toothpaste was slurried in simulated oral fluid (SOF) over a 3 hour period and the solids were isolated and analysed by Fourier transform infrared spectroscopy (FTIR).
  
  
  RESULTS
  The FTIR study demonstrated that calcium phosphate phases had formed and these became increasingly crystalline over 3 hours. CaSi was deposited onto enamel surfaces following one brushing with the toothpaste in vitro.The deposited particles showed evidence of HAP crystalline phases associated with the CaSi. Following 4 weeks brushing in vitro, the deposition increased and analyses showed that the deposited material was HAP. These results were confirmed by the in situ study.
  
  
  CONCLUSIONS
  Calcium silicate can be deposited onto enamel surfaces from a novel toothpaste formulation where it can form the enamel mineral HAP.
  
  
  CONCLUSIONS
  A novel toothpaste formulation containing CaSi can form HAP on enamel surfaces. The potential of this technology is for a novel approach to the repair of demineralised enamel and the protection of enamel during acid exposure.
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China. Electronic address: Yue-Kui.Sun@Unilever.com.
authors.forename: Yuekui
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Xiaoke
authors.initials: X
authors.lastname: Li
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Jianing N
authors.initials: JN
authors.lastname: Sun
authors.affiliation: Department of Preventive and Pediatric Dentistry, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Basic Research Academic Discipline, Shanghai 200011, China.
authors.forename: DanYing
authors.initials: D
authors.lastname: Tao
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China; Department of Preventive and Pediatric Dentistry, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Basic Research Academic Discipline, Shanghai 200011, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Qinghong
authors.initials: Q
authors.lastname: Hu
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Renjiang
authors.initials: R
authors.lastname: Liu
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Weining
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Preventive and Pediatric Dentistry, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Basic Research Academic Discipline, Shanghai 200011, China.
authors.forename: Xiping
authors.initials: X
authors.lastname: Feng
authors.affiliation: Unilever Oral Care, 66 Lin Xin Road, Shanghai 200335, China.
authors.forename: Jinfang
authors.initials: J
authors.lastname: Wang
authors.affiliation: Unilever Oral Care, Quarry Road East, Bebington, Wirral, CH63 3JW, UK.
authors.forename: Mel
authors.initials: M
authors.lastname: Carvell
authors.affiliation: Unilever Oral Care, Quarry Road East, Bebington, Wirral, CH63 3JW, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Joiner
mesh_terms: D000818:Animals; D002118:Calcium / Q000737:chemistry; D017610:Calcium Compounds / Q000494:pharmacology*; D002130:Calcium Phosphates / Q000737:chemistry; D002417:Cattle; D003461:Crystallography; D003743:Dental Enamel / Q000737:chemistry / Q000187:drug effects*; D044622:Dental Pellicle / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D005459:Fluorides / Q000494:pharmacology*; D005500:Follow-Up Studies; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010710:Phosphates / Q000494:pharmacology*; D011897:Random Allocation; D012464:Saliva, Artificial / Q000737:chemistry; D017640:Silicates / Q000494:pharmacology*; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D013997:Time Factors; D014099:Toothbrushing / Q000295:instrumentation / Q000379:methods; D014100:Toothpastes / Q000494:pharmacology*
chemical_list: D017610:Calcium Compounds; D002130:Calcium Phosphates; D010710:Phosphates; D012464:Saliva, Artificial; D017640:Silicates; D014100:Toothpastes; D017886:Durapatite; C020243:calcium phosphate; D005459:Fluorides; C031293:calcium silicate; C018279:sodium phosphate; D002118:Calcium
keywords: Calcium silicate; Enamel; Erosion; Hydroxyapatite; Mineralisation; Toothpaste