Anti‐inflammatory potential of a carvedilol gel in the pulpal tissue of rats after dental bleaching: A histopathological evaluation

Abstract

Aim Carvedilol is an antioxidant that decreases inflammation in periodontitis. The hydrogen peroxide (H2O2) of bleaching gel causes inflammation and necrosis of the dental pulp. In the present study, we evaluated the anti‐inflammatory potential of carvedilol in the pulp of rats after bleaching. Methods The right upper molars of rats received 35% H2O2 (1× 30 minutes), and the left upper molars were used as the control. Half of the rats received carvedilol gel (1× 10 minutes), forming the following groups: bleached, bleached followed by carvedilol (bleached+carvedilol), and control. After 2 and 30 days (N = 7 hemi‐maxillae/group), the rats were killed for histological evaluation, and statistical tests were performed (P < 0.05). Results After 2 days, the bleached group showed necrosis in the occlusal third of the coronal pulp, and in the bleached+carvedilol group, severe inflammation (P > 0.05), both different from the control (P < 0.05). In the middle third, the bleached group showed severe inflammation, and the bleached+carvedilol group showed moderate inflammation (P > 0.05), with the only difference between the bleached and control groups (P < 0.05). In the cervical third, the bleached group showed moderate inflammation, and the bleached+carvedilol group showed mild inflammation (P > 0.05). The difference again was only between the bleached and control groups (P < 0.05). At 30 days, there was no inflammation and a marked amount of tertiary dentin in bleached teeth (P > 0.05). Conclusion Carvedilol gel has the potential of minimizing H2O2 damage, especially in deep regions of the dental pulp of rats after bleaching.

Effect of dental bleaching on the microhardness and surface roughness of sealed composite resins

“…The results also demonstrated that bleaching with hydrogen peroxide or carbamide peroxide promoted a statistically significant decrease in the microhardness of the enamel samples studied (p < 0.05), for which reason the null hypothesis of the study was rejected. Some studies have reported a loss of calcium [9,11,[25][26][27], alterations in surface morphology [28,29], changed in chemical composition [30], and a decrease in enamel microhardness [25,28] in teeth subjected to bleaching procedures, the last of which was observed in the present study. These findings could be explained by daily exposure to bleaching substances with pH values ranging between 5.2 and 5.8, which could initiate a descaling process involving the loss of minerals such as calcium [31].…”

“…Carbamide peroxide is unstable and breaks down immediately upon contact with tissue and saliva, first dissociating into hydrogen peroxide and urea and subsequently into oxygen, water, and carbon dioxide [4,8]. The apparent mechanism of action of bleaching agents on tooth structures is the oxidation of dentin molecules, which causes color changes [9]. This oxidation reaction can interfere with the structural integrity of restorative materials [10].…”

Effect of antioxidant on tooth sensitivity after bleaching

“…15 Furthermore, numerous studies have examined the efficacy of sodium ascorbate in removing oxygen radicals generated by bleaching gels from enamel and dentin. 37,38,57…”

The Effects of Different Drugs with Anti-Inflamatory Potential in Prevention of Pulp Damage During the Teeth Bleaching

“…Although the effects of the hydrocortisone are more potent if they are applied systematically, due to the potential unwanted reactios such way of application is not justified within the scope of teeth sensitivity when it comes to the whitening (29)(30)(31). Carvedilol was applied in the form of gel by which teeth are covered after the bleaching treatment (32)(33)(34)(35) The effect mechanism depends on type and group to which the drug belongs. Corticosteroids and glycocorticoids represent the group of drugs which possess extremey potent anti-inflammatory effect, and are chemically extremely liposoluble drugs, which as such can unhindered penetrate to the cell membrane and reach the cytoplasmosis, and even penetrate the cell nucleus.…”