title: Diagnostic guide enabling distinction between taphonomic stains and enamel hypomineralisation in an archaeological context.
abstract: OBJECTIVE
  Molar Incisor Hypomineralisation (MIH) is a structural anomaly that affects the quality of tooth enamel and has important consequences for oral health. The developmentally hypomineralised enamel has normal thickness and can range in colour from white to yellow or brown with or without surface breakdown. The possibility of finding MIH in 'ancient populations' could downplay several current aetiological hypotheses (e.g., dioxin derivatives, bisphenols, antibiotics) without excluding the possible multifactorial aspect of the anomaly. In an archaeological context, chemical elements contained in the burial ground can stain teeth yellow or brown and therefore might create a taphonomic bias. The purpose of the present study is to test a proposed diagnostic guide enabling determination of the pathological or taphonomic cause of enamel discolouration and defects that resemble MIH present on 'ancient teeth'.
  
  
  METHODS
  Two sample groups including MIH discoloration (n=12 teeth) from living patients, taphonomic discoloration (n=9 teeth) and unknown discoloration (n=2 teeth) from medieval specimens were tested. Three non-destructive methods-Raman spectroscopy, X-ray micro-computed tomography and X-ray fluorescence were utilised.
  
  
  RESULTS
  Hypomineralised enamel has decreased mineral density (p<0.0001) and increased phosphate/β-carbonate ratio (p<0.01) compared to normal enamel whereas relative concentrations of manganese, copper, iron and lead are similar. In taphonomic discoloration, relative concentrations of these elements are significantly different (p<0.05) to normal enamel whereas mineral density and Raman spectra profile are comparable.
  
  
  CONCLUSIONS
  Enamel hypomineralisation can be distinguished from taphonomic staining in archaeological teeth.
authors.affiliation: Université de Bordeaux, UFR des Sciences Odontologiques, Bordeaux, France; Université de Bordeaux, PACEA, UMR 5199, Pessac, France. Electronic address: elsa.garot@u-bordeaux.fr.
authors.forename: Elsa
authors.initials: E
authors.lastname: Garot
authors.affiliation: Université de Bordeaux, PACEA, UMR 5199, Pessac, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Couture-Veschambre
authors.affiliation: Melbourne Dental School, University of Melbourne, Victoria, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Manton
authors.affiliation: Université de Bordeaux, ISM, UMS 3626, Talence, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Rodriguez
authors.affiliation: Université Bordeaux Montaigne, CRP2A, UMR 5060, Pessac, France.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Lefrais
authors.affiliation: Université de Bordeaux, UFR des Sciences Odontologiques, Bordeaux, France; Université de Bordeaux, PACEA, UMR 5199, Pessac, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Rouas
mesh_terms: D004396:Coloring Agents / Q000737:chemistry; D003743:Dental Enamel / Q000737:chemistry* / Q000473:pathology; D003744:Dental Enamel Hypoplasia / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007180:Incisor; D008903:Minerals / Q000032:analysis; D008963:Molar; D013057:Spectrum Analysis; D017001:Tooth Demineralization / Q000175:diagnosis* / Q000473:pathology; D014075:Tooth Discoloration / Q000175:diagnosis* / Q000473:pathology; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D004396:Coloring Agents; D008903:Minerals
keywords: Characterisation; Enamel; Hypomineralisation; MIH; Stain; Taphonomic