title: An ex vivo study of arrested primary teeth caries with silver diamine fluoride therapy.
abstract: OBJECTIVE
  This ex vivo study compared the physico-chemical structural differences between primary carious teeth biannually treated with silver diamine fluoride (SDF) and carious teeth without such treatment.
  
  
  METHODS
  Twelve carious primary upper-central incisors were collected from 6-year-old children. Six teeth had arrested caries after 24-month biannual SDF applications and 6 had active caries when there was no topical fluoride treatment. The mineral density, elemental contents, surface morphology, and crystal characteristics were assessed by micro-computed tomography (micro-CT), energy-dispersive X-ray spectrometry (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM).
  
  
  RESULTS
  Micro-CT examination revealed a superficial opaque band approximately 150μm on the arrested cavitated dentinal lesion. This band was limited in the active carious lesion. EDX examination detected a higher intensity of calcium and phosphate of 150μm in the surface zone than in the inner zone, but this zone was restricted in the active cavitated dentinal lesion. SEM examination indicated that the collagens were protected from being exposed in the arrested cavitated dentinal lesion, but were exposed in the active cavitated dentinal lesion. TEM examination suggested that remineralised hydroxyapatites were well aligned in the arrested cavitated dentinal lesion, while those in the active cavitated dentinal lesion indicated a random apatite arrangement.
  
  
  CONCLUSIONS
  A highly remineralised zone rich in calcium and phosphate was found on the arrested cavitated dentinal lesion of primary teeth with an SDF application. The collagens were protected from being exposed in the arrested cavitated dentinal lesion.
  
  
  CONCLUSIONS
  Clinical SDF application positively influences dentine remineralisation.
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong.
authors.forename: May L
authors.initials: ML
authors.lastname: Mei
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong.
authors.forename: L
authors.initials: L
authors.lastname: Ito
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong; College of Stomatology, Anhui Medical University, Hefei, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong.
authors.forename: Edward C M
authors.initials: EC
authors.lastname: Lo
authors.affiliation: College of Stomatology, Anhui Medical University, Hefei, China. Electronic address: ql-li@126.com.
authors.forename: Q L
authors.initials: QL
authors.lastname: Li
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong. Electronic address: chchu@hku.hk.
authors.forename: C H
authors.initials: CH
authors.lastname: Chu
mesh_terms: D002118:Calcium / Q000032:analysis; D002327:Cariostatic Agents / Q000627:therapeutic use*; D055598:Chemical Phenomena; D002648:Child; D003094:Collagen / Q000648:ultrastructure; D003461:Crystallography; D003731:Dental Caries / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003804:Dentin / Q000737:chemistry / Q000187:drug effects / Q000648:ultrastructure; D017886:Durapatite / Q000032:analysis; D005459:Fluorides / Q000032:analysis; D005460:Fluorides, Topical; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007180:Incisor / Q000737:chemistry / Q000187:drug effects* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010758:Phosphorus / Q000032:analysis; D000644:Quaternary Ammonium Compounds / Q000627:therapeutic use*; D012834:Silver / Q000032:analysis; D018030:Silver Compounds; D013052:Spectrometry, X-Ray Emission; D014089:Tooth Remineralization / Q000379:methods*; D014094:Tooth, Deciduous / Q000737:chemistry / Q000187:drug effects* / Q000648:ultrastructure; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D002327:Cariostatic Agents; D005460:Fluorides, Topical; D000644:Quaternary Ammonium Compounds; D018030:Silver Compounds; D010758:Phosphorus; D012834:Silver; D003094:Collagen; D017886:Durapatite; C024633:silver diamine fluoride; D005459:Fluorides; D002118:Calcium
keywords: Collagen; Dentine; Silver diamine fluoride