Influência da clorexidina na resistência de união longitudinal à dentina: estudo in vitro / Influence of chlorhexidine on longitudinal bond strength to dentin: in vitro study

Objetivo: Este estudo avaliou o efeito da solução de gluconato de clorexidina 0,2% (CHX) usado como primer terapêutico sobre a resistência de união longitudinal de adesivo convencional a dentina. Material e Métodos: dentes bovinos foram desgastados para obter uma área de dentina, e foram divididos em 2 grupos: Grupo C (Controle) - ácido fosfórico à 37%) + 0,2% CHX por 30s + Single Bond. Blocos de resina composta form fabricados e armazenados por 24 h e 6 meses, seccionados e submetidos ao teste de resistência a microtração. Os resultados foram analisados por ANOVA dois-fatores seguido pelo teste de Tukey. Resultados: Valores de média (±Desvio-padrão) (MPa): Grupo CHX/24h - 41,8(±2,62)A; Grupo C/24h - 40,8(±3,35)AB; Grupo CHX/6 meses ­ 36,4(±3,52)B; Grupo CHX/6 meses - 26,1(±1,54) C. Resultados: Valores de média (±Desvio-padrão) (MPa): CHX (24 h) ­ 41,76 (±2,62)a; C (24h) ­ 40,81 (±3,35)ab; GT (24h): 37,38(2,98)abc; CHX (6 meses) ­ 36,04 (±3,52) bcd; EGCG (24h) ­ 35,91 (±4,82)cd; EGCG (6 meses) ­ 35,75 (±4,44)cd; GT (6 meses) ­ 31,95 (±3,40)de; C (6 meses): 30,05 (±1,54)e. Conclusão: CHX aumentou a resistência de união imediata da interface dentina-resina e significantemente reduziu a perda de resistência de união após 6 meses de armazenagem em água quando comparado ao grupo controle.(AU)

Objective: This study evaluated the effect of 0.2% chlorhexidine gluconate solution used as an therapeutic primer on the long-term bond strength of etch-and-rinse adhesive to dentin. Material and Methods: Bovine incisors were worn to expose an area of dentin and were divided into 2 groups: Group C (Control) - acid etching with 37% phosphoric acid + Single Bond; Group CHX (0.2% CHX) - acid etching with 37% phosphoric acid + 0.2% CHX for 30 s + Single Bond. Blocks of composite were fabricated and stored for 24 h or 6 months, sectioned into beams and submitted to microtensile tests. Results were analyzed by two-way ANOVA and Tukey tests. Results: Mean (±SD) values (in MPa) were as follow: Group CHX/24h - 41.8(±2.62)A; Group C/24h - 40.8(±3.35)AB; Group CHX/6 months ­ 36.4(±3.52)B; Group CHX/6 months - 26.1(±1.54)C. Conclusion: CHX improve the imediatte bond strength of resin-dentin and significantly lowered the loss of bond strength after 6 months water storage as seen in the control bonds.(AU)

Effect of chlorhexidine, green tea and egcg as therapeutic primers to increase the durability of resin-dentin bond / Efeito da clorexidina, do chá verde e do EGCG como primers terapêuticos para aumentar a durabilidade da adesão resinadentina

Objetivo: este estudo avaliou o efeito da solução de gluconato de clorexidina 0,2% (CHX), do chá verde e do componente ativo epigallocatequina 3-gallato (gel de EGCG) usados como primers terapêuticos sobre a resistência de união longitudinal de adesivo convencional a dentina. Material e Métodos: oitenta dentes bovinos foram desgastados para obter uma área de dentina plana, que foi condicionada (ácido fosfórico à 37%) seguida de lavagem. Os dentes foram divididos em 4 grupos (n- 20): Grupo C (Controle) - Single Bond; Grupo CHX – 0,2% CHX por 30s + Single Bond; Grupo EGCG - gel de EGCG 10µM por 30s + Single Bond; Group GT – chá verde aquoso por 30s + Single Bond. Blocos de resina composta form fabricados e armazenados por 24 h e 6 meses, seccionados e submetidos ao teste de resistência a microtração. Os resultados foram analisados por ANOVA dois-fatores seguido pelo teste de Tukey. Resultados: Valores de média (±Desvio-padrão) (MPa): CHX (24 h) – 41,76 (±2,62)a; C (24 h) – 40,81 (±3,35)ab; GT (24h): 37,38(2,98)abc; CHX (6 meses) – 36,04 (±3,52) bcd; EGCG (24h) – 35,91 (±4,82)cd; EGCG (6 meses) – 35,75 (±4,44)cd; GT (6 meses) – 31,95 (±3,40)de; C (6 meses): 30,05 (±1,54)e. Conclusão: O gel de EGCG produziu uma interface adesiva dentina-resina que não alterou os valores de resistência de união após 6 meses de armazenagem em água, mas reduziu a resistência de união para o tempo de 24 h quando comparado com os grupos Controle e CHX.

Objective: This study evaluated the effect of 0.2% chlorhexidine gluconate solution (CHX), green tea and active epigallocatechin-gallate (EGCG) used as therapeutic primers on the longterm bond strength of etch-and-rinse adhesive to dentin. Material and Methods: Eighty bovine incisors were worn to expose an area of dentin, that were acid-etched (37% phosphoric acid) and rinsed. The teeth were divided into 4 groups (n = 20): Group C (Control) - Single Bond; Group CHX - 0.2% CHX for 30s + Single Bond; Group EGCG - active EGCG gel at 10 µM for 30 s + Single Bond; Group GT - aqueous green tea for 30s + Single Bond. Blocks of composite were fabricated and stored for 24 h or 6 months, sectioned into beams and submitted to microtensile tests. Results were analyzed by two-way ANOVA and Tukey’s test (5%). Results: Mean (±SD) values (in MPa) were as follow: CHX (24 h) – 41.76 (±2.62); C (24 h) - 40.81 (±3.35); GT (24 h): 37.38(2.98); CHX (6 months) - 36.04 (±3.52); EGCG (24h) - 35.91 (±4.82); EGCG (6 months) - 35.75 (±4.44); GT (6 months) - 31.95 (±3.40); C (6 months): 30.05 (±1.54). Conclusion: EGCG produced resin-dentin bonds that did not change after 6 months water storage but it decreased the immediate bond strength when compared to control and chlorhexidine groups

Microshear bond strength of adhesives according to the direction of enamel rods / 대한치과보존학회지

This study compared the microshear bond strength (microSBS) to end and side of enamel rod bonded by four adhesives including two total etch adhesives and two self-etch adhesives. Crown segments of extracted human molars were cut mesiodistally. The outer buccal or lingual surface was used as specimens cutting the ends of enamel rods, and inner slabs used as specimens cutting the sides of enamel rods. They were assigned to four groups by used adhesives: Group 1 (All-Bond 2), Group 2 (Single Bond), Group 3 (Tyrian SPE/One-Step Plus), Group 4 (Adper Prompt L-Pop). After each adhesive was applied to enamel surface, three composite cylinders were adhered to it of each specimen using Tygon tube. After storage in distilled water for 24 hours, the bonded specimens were subjected to microSBS testing with a crosshead speed of 1 mm/minute. The results of this study were as follows; 1. The microSBS of Group 2 (16.50 +/- 2.31 MPa) and Group 4 (15.83 +/- 2.33 MPa) to the end of enamel prism was significantly higher than that of Group 1 (11.93 +/- 2.25 MPa) and Group 3 (11.97 +/- 2.05 MPa) (p < 0.05). 2. The microSBS of Group 2 (13.43 +/- 2.93 MPa) to the side of enamel prism was significantly higher than that of Group 1 (8.64 +/- 1.53 MPa), Group 3 (9.69 +/- 1.80 MPa), and Group 4 (10.56 +/- 1.75 MPa) (p < 0.05). 3. The mean microSBS to the end of enamel rod was significantly higher than that to the side of enamel rod in all group (p < 0.05).