Polymeric biomaterials maintained the esthetic efficacy and reduced the cytotoxicity of in‐office dental bleaching

Abstract

Evaluate the kinetics of hydrogen peroxide (H 2 O 2 ) degradation, esthetic efficacy and cytotoxicity of a bleaching gel with 35%H 2 O 2 applied on enamel previously covered or not with polymeric nanofibrillar scaffold (SNan), polymeric primer catalyst (PPol), and both. Standardized enamel/dentin discs (n = 128) obtained from bovine teeth were adapted to pulp chambers. After covering enamel with the polymeric products, the bleaching gel was applied for 45 min, establishing the following groups: G1: no treatment (negative control); G2: 35%H 2 O 2 (positive control); G3: SNan; G4: PPol; G5: SNan + PPol; G6: SNan + 35%H 2 O 2 ; G7: PPol + 35%H 2 O 2 ; G8: SNan + PPol + 35%H 2 O 2 . The kinetics of H 2 O 2 degradation (n = 8), bleaching efficacy (ΔE/ΔWI; n = 8), trans-amelodentinal cytotoxicity (n = 8), and cell morphology (n = 4) were assessed (ANOVA/Tukey test; p < 0.05). Greater H 2 O 2 degradation occurred in G7 and G8. Bleaching efficacy (ΔE) was higher in G6, G7, and G8 in comparison with G2 (p < 0.05). However, no difference was observed for ΔWI (p > 0.05). G8 presented the lower level of trans-amelodentinal diffusion of H 2 O 2 , oxidative stress, and toxicity to the MDPC-23 cells (p < 0.05). Polymeric biomaterials increased the kinetics of H 2 O 2 decomposition, as well as maintained the esthetic efficacy and minimized the cytotoxicity caused by a bleaching gel with 35%H 2 O 2 .Clinical Significance: Application of a bleaching gel with 35%H 2 O 2 on enamel previously covered by polymeric biomaterials maintains the esthetic efficacy and reduces the cytotoxicity caused by a single session of in-office dental bleaching.

A new approach for professional dental bleaching using a polymeric catalyst primer

“…The dentin surface of the E/DDs was manually regularized by wear with sandpapers of 400 and 600-granulations (T469-SF-Noton; Saint-Gobain Abrasivos Ltda, Jundiaí, SP, Brazil) until reaching the final thickness of 2.3 mm (Figure 1C). 10,11,28 After staining the standardized E/DDs with black tea, 11,28 they were homogeneously distributed into groups (Table 1). In G2, G4, G6, and G8, the total volume of 10 μl of PCP was applied with a micropipette for viscous products (Microman M50; Gilson Inc., Middleton, WI, USA), and the tip was used to distribute the bioproduct on the entire enamel surface.…”

“…The association of chemical substances capable of catalyzing H 2 O 2 seems to characterize a promising strategy to optimize in-office bleaching protocol. 11,12,28 The use of chemical activators derived from MnO has been reported by several researchers. 12,16,19 This metal oxide participates in H 2 O 2 catalysis, promoting its degradation and producing other ROS.…”

“…Thus, the present study added MnO to a cellulose‐derived nontoxic semisynthetic polymer, which has been extensively used in the pharmaceutical industry for controlled drug release 26,27 . The strategy of developing bioproducts containing catalyst molecules, which are applied on enamel before the bleaching gels, has already been reported in the literature 28,29 . In these studies, the authors showed that such innovative approach can also improve the esthetic outcome and decrease the trans‐amelodentinal cytotoxicity (TC) of the conventional ITB therapy.…”

“…26,27 The strategy of developing bioproducts containing catalyst molecules, which are applied on enamel before the bleaching gels, has already been reported in the literature. 28,29 In these studies, the authors showed that such innovative approach can also improve the esthetic outcome and decrease the trans-amelodentinal cytotoxicity (TC) of the conventional ITB therapy. The bioproduct obtained, termed as polymeric catalyst primer (PCP), could be used to coat the enamel before applying the bleaching gel in a promising strategy to accelerate tooth bleaching and reduce the amount of free-H 2 O 2 capable of reaching the pulp chamber.…”

O uso de fontes de luz em protocolos clareadores: alteração de cor, temperatura, transmitância e irradiância Estudo in vitro

“…Segundo Kenneth Markowitz (15) a sensibilidade ao clareamento dental pode ser devido a ativação direta de canais TRPA1 de fibras nervosas tipo C pulpares pela chegada de peróxido de hidrogênio (H2O2) não reagente (16). Nos últimos anos, estudos clínicos tem mostrado que além da concentração de H2O2, fatores como: tempo de aplicação dos géis e a espessura do esmalte e da dentina podem aumentar o efeito adverso do clareamento de consultório (17,18) Recentemente, foi lançado no mercado pela empresa brasileira MMOptics, um aparelho que irradia luz violeta a partir de uma fonte LED, com o comprimento de onda entre 405-410 nm. A emissão de luz nesse comprimento de onda coincide com o pico de absorção dos pigmentos, o qual interage seletivamente com os mais escuros, quebrando-os em cadeias menores, mais claras.…”