Food restriction reduces hepatic alterations associated with experimental periodontitis.

BACKGROUND: Periodontitis is a chronic inflammatory and multifactorial disease that affects the periodontal structures and can cause alterations in the hepatic tissue. The aim of the present study was to evaluate whether a diet with food restriction can decrease oral and liver alterations associated with ligature-induced periodontitis. METHODS: Twenty-four female Wistar rats were used in this study, randomized into three groups (n = 8 for each group): control (regular food); periodontitis (regular food + periodontitis induced with ligatures); and food restriction (diet with food restriction and periodontitis induction). The following periodontium parameters were analyzed tooth mobility (TM), probing pocket depth (PPD), gingival bleeding index (GBI), and alveolar bone height (ABH). In the liver, the levels of oxidative stress markers-malondialdehyde (MDA), glutathione (GSH), total cholesterol, and levels of myeloperoxidase (MPO) activity were measured. Liver samples were analyzed for histopathological score. In the blood tissue, the levels of enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), glucose, total cholesterol, and the high-density lipoprotein (HDL) were also evaluated. RESULTS: The animals that received a diet with food restriction + periodontitis showed a decrease in hepatic histopathological score (P < 0.05) when compared with the periodontitis group, the same for glucose, total cholesterol, ALT, AST, and ABH data. The group with food restriction + periodontitis showed a decrease in the histopathological liver score (P < 0.05) compared with the group with periodontitis. CONCLUSION: This study revealed that food restriction reduced oral damages, as well as hepatic, blood and alveolar bone alterations associated with ligature-induced periodontitis in rats.

A swift, easy and cheap protocol to evaluate the tooth bleaching in vitro.

BACKGROUND: This study aims to develop a protocol that optimizes in vitro dental bleaching procedures in a cheap, fast and accessible manner. MATERIAL AND METHODS: 18 bovine incisors were cut and polished in enamel/dentin and submitted to staining in coffee solution during 72 hours. After the standardization and staining of the enamel surfaces, three groups (n = 6) were formed to receive three different gels, WHITENESS (commercial gel); H2O2 - 5% (manipulated gel); CARBOPOL GEL (manipulated gel and without H2O2). The color of the enamel surfaces was evaluated using digital images, obtained with digital camera and controlled luminosity, before and after staining, as well as after each bleaching step. RESULTS: The average bleaching after 48 hours of procedure was: WHITENESS with 13.6 (± 1.2); H2O2 (5%) with 9.8 (± 1.4) and CARBOPOL GEL with 2.9 (± 0.6). After 72 hours, WHITENESS presented a mean of 15.8 (± 0.7), the H2O2 group (5%) 14.4 (± 1.5) and CARBOPOL GEL 4.6 (± 1.0). After completing 96 hours of whitening, WHITENESS presented an average of 18.3 (± 0.8), H2O2 (5%) 16.7 (± 1.4) and CARBOPOL GEL 7.3 (± 0.8). Our data demonstrated that the protocol development for us can be used to evaluate dental bleaching in a short time, with 96 hours already was possible to detect significant differences, when compared with the longer times of experimental dental bleaching. CONCLUSIONS: The proposed protocol guarantees statistically significant results in 96 hours, confirming the efficacy, cheapness, viability and practicality of the protocol developed in this study. Key words:Enamel, color, aesthetics.