title: Correlation between light transmission and permeability of human dentin.
abstract: The influence of dentin permeability on transdentinal LED light propagation should be evaluated since this kind of phototherapy may further be clinically used to stimulate the metabolism of pulp cells, improving the healing of damaged pulps. This study evaluated the influence of the dentin permeability on the transdentinal LED light (630 nm) transmission. Forty-five 0.5-mm-thick dentin disks were prepared from the coronal dentin of extracted sound human molars. An initial measurement of transdentinal LED light transmission was carried out by illuminating the discs in the occlusal-to-pulpal direction onto a light power sensor to determine light attenuation. The discs were treated with EDTA for smear layer removal, subjected to analysis of hydraulic conductance, and a new measurement of transdentinal LED light transmission was taken. Spearman's correlation coefficient was used for analysis of data and showed a weak correlation between dentin permeability and light attenuation (coefficient = 0.19). This result indicates that higher or lower dentin permeability does not reflect the transdentinal propagation of LED light. Significantly greater transdentinal propagation of light was observed after treatment of dentin surface with EDTA (Wilcoxon test, p < 0.05). According to the experimental conditions of this in vitro study, it may be concluded that dentin permeability does not interfere in the transdentinal LED light transmission, and that smear layer removal facilitates this propagation.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, UNESP-University Estadual Paulista, Araraquara, SP, Brazil.
authors.forename: Ana Paula Silveira
authors.initials: AP
authors.lastname: Turrioni
authors.forename: Camila Fávero
authors.initials: CF
authors.lastname: de Oliveira
authors.forename: Fernanda Gonçalves
authors.initials: FG
authors.lastname: Basso
authors.forename: Lilian Tan
authors.initials: LT
authors.lastname: Moriyama
authors.forename: Cristina
authors.initials: C
authors.lastname: Kurachi
authors.forename: Josimeri
authors.initials: J
authors.lastname: Hebling
authors.forename: Vanderlei S
authors.initials: VS
authors.lastname: Bagnato
authors.forename: Carlos Alberto de Souza
authors.initials: CA
authors.lastname: Costa
mesh_terms: D055117:Curing Lights, Dental; D003804:Dentin / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D003806:Dentin Permeability / Q000528:radiation effects; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D008027:Light; D008964:Molar, Third / Q000502:physiology; D010789:Phototherapy / Q000295:instrumentation / Q000379:methods; D016369:Smear Layer
chemical_list: D004492:Edetic Acid