title: Multiphoton imaging of the dentine-enamel junction.
abstract: Multiphoton microscopy has been used to reveal structural details of dentine and enamel at the dentin-enamel junction (DEJ) based on their 2-photon excited fluorescence (2PEF) emission and second harmonic generation (SHG). In dentine tubule 2PEF intensity varies due to protein content variation. Intertubular dentin produces both SHG and 2PEF signals. Tubules are surrounded by a thin circular zone with a lower SHG signal than the bulk dentine and the presence of collagen fibers perpendicular to the tubule longitudinal axis is indicated by strong SHG responses. The DEJ appears as a low intensity line on the 2PEF images and this was never previously reported. The SHG signal is completely absent for enamel and aprismatic enamel shows a homogeneous low 2PEF signal contrary to prismatic enamel. The SHG intensity of mantle dentine is increasing from the dentine-enamel junction in the first 12 μm indicating a progressive presence of fibrillar collagen and corresponding to the more external part of mantle dentine where matrix metallo-proteases accumulate. The high information content of multiphoton images confirms the huge potential of this method to investigate tooth structures in physiological and pathological conditions.
authors: Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France.
authors: Thierry
authors: T
authors: Cloitre
authors: Ivan V
authors: IV
authors: Panayotov
authors: Hervé
authors: H
authors: Tassery
authors: Csilla
authors: C
authors: Gergely
authors: Bernard
authors: B
authors: Levallois
authors: Frédéric J G
authors: FJ
authors: Cuisinier
mesh_terms: D002130:Calcium Phosphates / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D003743:Dental Enamel / Q000166:cytology*; D003804:Dentin / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*
chemical_list: D002130:Calcium Phosphates; C065819:Collagraft; D003094:Collagen