title: Nanoleakage distribution at adhesive-dentin interfaces in 3D.
abstract: In spite of its role in the degradation of tooth-biomaterial interfaces, reports on nanoleakage are largely inconsistent. The aim of this work was to assess nanoleakage patterns qualitatively and quantitatively in 3D, to determine the influence of direction, position, and inclination of the field-of-view. Therefore, we applied a gold-standard 3-step etch-and-rinse adhesive to bur-cut dentin surfaces, after which interface samples were sectioned, infiltrated with an ammoniacal silver-nitrate solution, and embedded by common TEM procedures. High-resolution 3D models of interfaces were then generated by FIB and electron tomography, following strict conditions determined by Monte Carlo simulations. Inverted images in FIB tomography disclosed morphological characteristics analogous to those revealed by TEM. Quantitative analysis revealed large variations in silver-nitrate uptake between 2D image projections in different directions. Furthermore, silver-nitrate fractions in individual 2D image projections were seldom related to the total 3D volumetric fraction. Electron tomography showed that inclination also affected the morphology of silver-nitrate patterns. In conclusion, conventional nanoleakage evaluation is heavily influenced by direction, position, and inclination of the field-of-view, and thus may contain artifacts.
authors.affiliation: Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Coutinho
authors.forename: M V
authors.initials: MV
authors.lastname: Cardoso
authors.forename: C P
authors.initials: CP
authors.lastname: Fernandes
authors.forename: A A
authors.initials: AA
authors.lastname: Neves
authors.forename: C V D
authors.initials: CV
authors.lastname: Gouvea
authors.forename: K L
authors.initials: KL
authors.lastname: Van Landuyt
authors.forename: J
authors.initials: J
authors.lastname: De Munck
authors.forename: B
authors.initials: B
authors.lastname: Van Meerbeek
mesh_terms: D016477:Artifacts; D004396:Coloring Agents; D001840:Dental Bonding / Q000009:adverse effects*; D003763:Dental Leakage / Q000175:diagnosis* / Q000209:etiology; D003804:Dentin / Q000473:pathology*; D017220:Dentin-Bonding Agents; D021621:Imaging, Three-Dimensional / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D009010:Monte Carlo Method; D019279:Resin Cements; D012542:Scattering, Radiation; D012834:Silver; D012835:Silver Nitrate; D014054:Tomography / Q000379:methods
chemical_list: D004396:Coloring Agents; D017220:Dentin-Bonding Agents; C469607:OptiBond FL; D019279:Resin Cements; C000212:ammoniacal silver; D012834:Silver; D012835:Silver Nitrate