Hydroxyapatite-based cements induce different apatite formation in radicular dentin Toledano Osorio, Manuel Sánchez Aguilera, Fátima Osorio Ruiz, Raquel Muñoz Soto, Esther Pérez-Álvarez, M.C. López López, Modesto Torcuato Lynch, Christopher D. Toledano Pérez, Manuel Crystallinity dentin microscopy remineralization TEM XRD Objectives. To investigate crystallinity and ultrastructure of the formed hydroxyapatite at radicular cervical and apical dentin after being treated with three different canal sealers. Methods. Cervical and apical root dentin surfaces were treated with two experimental hydroxyapatite-based sealers, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite) and an epoxy resin-based canal sealer (AH Plus); gutta-percha without sealer was included as control. Dentin surfaces were studied by X-ray diffraction and transmission electron microscopy through selected area diffraction and bright-field imaging after 24 h and 12 m of storage. Results. Root cervical dentin treated with calcypatite and oxipatite produced poor crystallinity of new minerals, wide amorphous phase and non-stoichiometry. Reflections at the 002 plane and the corresponding diffraction rings attained lower values in the Scherrer equation and the Scherrer-Wilson equation in samples treated with both HAp-based sealers than in specimens without sealer or with AH Plus. At root cervical dentin treated with calcypatite, shorter and wider crystallite size formations and lower crystals grain size were found, if compared to those encountered at oxipatite treated dentin. Oxipatite attained improved crystallographic atomic order and less structural variation in both distances and angles. Apical dentin treated with oxipatite attained preferred grain orientation with polycrystalline lattices. Significance. The immature crystallites formed in dentin treated with calcypatite and oxipatite will account for high hydroxyapatite solubility and remineralizing activity. New polycrystalline formations encountered in apical dentin treated with oxipatite may also produce high mechanical performance. 2020-05-18T11:41:08Z 2020-05-18T11:41:08Z 2020 info:eu-repo/semantics/article Toledano-Osorio M., Aguilera F.S., Osorio R., Muñoz-Soto E., Pérez-Álvarez M.C., López-López M.T., Lynch C.D. Hydroxyapatite-based cements induce different apatite formation in radicular dentin (2020) Dental Materials, 36 (1), pp. 167-178. http://hdl.handle.net/10481/62101 https://doi.org/10.1016/j.dental.2019.11.023 eng http://creativecommons.org/licenses/by-nc-nd/3.0/es/ info:eu-repo/semantics/openAccess Atribución-NoComercial-SinDerivadas 3.0 España ELSEVIER SCIENCE BV