The effect of dental bleaching on pulpal tissue response in a diabetic animal model: A study of immunoregulatory cytokines

Abstract

Aim

To evaluate the influence of dental bleaching in immunoregulatory cytokines production (IL-6, TNF-α, and IL-17) in the pulp tissue of normoglycaemic and diabetic rats.

Methodology

Twenty-eight rats were divided in normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with a single dose of alloxan diluted in citrate buffer via intramuscular injection. After DM confirmation, all rats were sedated and dental bleaching was performed using 35% hydrogen peroxide in the right maxillary molars for 30 minutes. Left molars were used as controls. Bleaching resulted in 4 hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D), and D-bleached (DBle). After 2 and 30 days, rats were euthanized and hemimaxillae processed for analysis by haematoxylin-eosin and immunohistochemistry. Results within and between animals were submitted to Wilcoxon signed-rank and Mann-Whitney tests (P < 0.05).

Results

At 2 days, the NBle group had mild, and the DBle had severe inflammatory infiltration in the pulpal tissue (P < 0.05). TNF-α and IL-6 cytokines were associated with increased immunolabelling in the bleached groups compared to nonbleached (P < 0.05). However, IL-17 had increased immunolabelling in the NBle compared to the N and DBle group (P < 0.05). At 30 days, reactionary dentine was observed in the coronal pulp of all bleached teeth and no inflammation was present (P > 0.05). TNF-α cytokines had increased immunolabelling in the DBle group compared to the D group (P < 0.05). However, for IL-6 and IL-17, no difference was observed in this period (P > 0.05).

Conclusions

Dental bleaching increased IL-6 and TNF-α in the pulp tissue regardless of Diabetes mellitus; however, diabetic rats had higher TNF-α levels for longer periods. Dental bleaching influenced the increase of IL-17 in the early periods in normoglycaemic rats.

This article is protected by copyright. All rights reserved.

http://ift.tt/2vK6RBy