The number of bleaching sessions influences pulp tissue damage in rat teeth.

Autor: Cintra LT; Department of Endodontics, Araçatuba Dental School, UNESP-Universidade Estadual Paulista, São Paulo, Brazil. Electronic address: lucianocintra@foa.unesp.br., Benetti F, da Silva Facundo AC, Ferreira LL, Gomes-Filho JE, Ervolino E, Rahal V, Briso AL
Jazyk: angličtina
Zdroj: Journal of endodontics [J Endod] 2013 Dec; Vol. 39 (12), pp. 1576-80. Date of Electronic Publication: 2013 Sep 21.
DOI: 10.1016/j.joen.2013.08.007
Abstrakt: Introduction: Hydrogen peroxide tooth bleaching is claimed to cause alterations in dental tissue structures. This study investigated the influence of the number of bleaching sessions on pulp tissue in rats.
Methods: Male Wistar rats were studied in 5 groups (groups 1S-5S) of 10 each, which differed by the number (1-5) of bleaching sessions. In each session, the animals were anesthetized, and 35% hydrogen peroxide gel was applied to 3 upper right molars. Two days after the experimental period, the animals were killed, and their jaws were processed for light microscope evaluation. Pulp tissue reactions were scored as follows: 1, no or few inflammatory cells and no reaction; 2, <25 cells and a mild reaction; 3, between 25 and 125 cells and a moderate reaction; and 4, 125 or more cells and a severe reaction. Results from each experimental group were compared between groups and within groups to the corresponding unbleached upper left molars and analyzed for significant differences using the Kruskal-Wallis test (P < .05).
Results: All tissue sections showed significant bleaching-induced changes in the dental pulp. After 1 bleaching session, necrotic tissue in the pulp horns and underlying inflammatory changes were observed. The extent and intensity of these changes increased with the number of bleaching sessions. After 5 sessions, the changes included necrotic areas in the pulp tissue involving the second third of the radicular pulp and intense inflammation in the apical third.
Conclusions: The number of bleaching sessions directly influenced the extent of pulp damage.
(Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE