Relação entre doença periodontal e anemia / Relationship between periodontal diseases and anemia

Doença Periodontal é um grupo de doenças inflamatórias de origem infecciosa que afetam os tecidos de proteção e sustentação do dente. A perpetuação da resposta do hospedeiro devido à infecção bacteriana persistente interrompe os mecanismos homeostáticos e resulta na liberação de citocinas pró-inflamatórias, proteases e prostanóides, que podem promover destruição da matriz extracelular na gengiva e estimular a reabsorção óssea, além de estimular a produção de proteínas de fase aguda, sendo a IL-6 seu principal indutor. Dentre as proteínas de fase aguda cuja produção é intensamente aumentada durante a infecção e inflamação está a hepcidina que é predominantemente produzida pelo fígado, tendo como principal função a regulação homeostática do metabolismo de ferro, a modulação da defesa orgânica e contribuindo para a patogênese de anemias de causas diversas. O objetivo do estudo foi realizar uma revisão da literatura utilizando uma consulta às bases de dados Cochrane, Bireme e MedLine, tendo como eixo as seguintes palavras-chaves em associação: periodontite crônica, Inflamação e hemoglobina. Foram encontradas 101 publicações científicas por meio de busca eletrônica, sendo 9 da Bireme, 21 do Pubmed e 71 da Cochrane, além de títulos oriundos de referências de outros artigos. Concluiu-se que há indícios que hepcidina esteja associada ao processo inflamatório sendo responsável pela homeostase do ferro e, desta forma, contribuindo para processo patológico da anemia da inflamação crônica. Constatou-se ainda a escassez de artigos que investiguem a possível associação entre a doença periodontal e a anemia

Periodontal diseases can be defined as inflammatory disease from infectious origin that affect the protection and support tooth tissues. The host response perpetuation due to persistent bacterial infection disrupts the homeostatic mechanisms and results in releasing of the proinflammatory cytokines, proteases and prostanoids that can promote the destruction of extracellular matrix in the gingiva and cause bone resorption, also stimulate the production of acute phase proteins, being the IL-6 the main inductor. Among the acute phase proteins whose production is widely increased during infection and inflammation, there is hepcidin which is predominantly produced by the liver, having as main function the homeostatic regulation of iron metabolism, organic defense modulation and contributing to the pathogenesis of various causes of anemias. The aim of the study was to perform a literature review by using databases Cochrane, Bireme and MedLine, and the following keywords in combination: chronic periodontitis, inflammation and hemoglobin. A total of 101 scientific publications was found by electronic search, 9 from Bireme, 21 from PubMed and 71 from Cochrane, also titles from references by other articles. It was concluded that the hepcidin is associated to inflammatory process and it is responsible for the iron homeostasis therefore leading is associated to the pathologic process of the chronic disease anemia. Also, it was noted the lack of manuscripts that investigate the possible association between periodontal diseases and anemia.

Effect of substrate and adhesive system type on composite resin restorations

Introduction: Although it is possible to obtain a reliable bond between enamel and composite resin, the ideal bonding method of composite resin to dentin still needs to be developed. Variables such as the type of adhesive system used and type of dentin substrate can influence on the adhesion. Objective: The purpose of this study was to compare the shear bond strength of composite resin restorations to human and bovine dentin using three adhesive systems. Material and methods: Fifteen human third molars sectioned into two halves and 30 bovine incisors were cut into blocks (4x4mm), embedded in acrylic resin and ground flat to expose the dentin. The specimens were randomly divided into six groups (n = 10): group 1 - human dentin using Scotchbond Multi-Purpose; group 2 - human dentin using Adper Single Bond 2; group 3 - human dentin using Adper Prompt L-Pop; group 4 - bovine dentin using Scotchbond Multi-Purpose; group 5 - bovine dentin using Adper Single Bond 2; group 6 - bovine dentin using Adper Prompt L-Pop. After composite resin restoration procedure, the specimens were stored into distilled water for 24h at 37ºC and then submitted to the shear test using a universal testing machine. The failure patterns were examined microscopically and classified as adhesive, cohesive in resin, cohesive in dentin or both, and mixed. The ANOVA (two-way) and Tukey's post hoc were used. Chi-square test for independence was used for analysis of failure mode. The significance level was set at 5%. Results: A significant difference in shear bond strength was observed among adhesive systems (p = 0.031), with higher values for one-bottle adhesive (8.87±2.72) and lower for self-etching (6.38±3.15), and between the two types of substrate (p = 0.018), with higher values for human dentin. However, there was no significant difference for the adhesive system/substrate interaction (p = 0.11). Adhesive failure was the predominant failure mode for all adhesive systems and for the two substrates. Conclusion: Shear bond strength was different between human and bovine substrates and for the adhesive system used.

Evaluation of shear bond strength of orthodontic resin and resin modified glass ionomer cement on bonding of metal and ceramic brackets

Objective:The aim of this study was to evaluate the shear bond strength of orthodontic resin and resin-modified glass ionomer cement on bonding of metal and ceramic brackets. Material and methods: Forty bovine teeth were sectioned and embedded into PVC with chemically-cured acrylic resin. The labial surfaces were flattened and received prophylaxis with pumice and water. Then they were divided into four groups, according to the bonding material and the type of bracket. Group 1: metallic bracket + Transbond XT; Group 2: metallic bracket + Vitremer; Group 3: ceramic bracket + Transbond XT; Group 4: ceramic bracket + Vitremer. The bonding was performed according to the manufacturers’ recommendations. The shear bond strength test was conducted in a universal testing machine (TIRAtest 2420) at a crosshead speed of 0.5 mm/min. Then, the fractured surfaces were evaluated using a stereomicroscope (x15 magnification) to check the adhesive remnant index. Data was subjected to two-way ANOVA and Tukey’s test for pairwise comparisons (a = 0.05).Results: The results suggested a non-significant effect of the interaction (p > 0.97), and only main factors were significant (p = 0.0001). The bond strength of Transbond XT was statistically higher than Vitremer. Ceramic brackets obtained the highest values of resistance when compared with metal brackets. Conclusion: The ceramic brackets bonded with Transbond XT orthodontic resin have excellent bond strength results.

Resistência de união de dois sistemas adesivos ao esmalte bovino / Bond strength of two adhesive systems to bovine enamel

Objetivo: avaliar a resistência de união às forças de cisalhamento de dois sistemas adesivos, um convencional e um autocondicionante, em esmalte de dente bovino. Métodos: trinta e duas placas de esmalte bovino (16mm2) foram confeccionadas e divididas aleatoriamente, em dois grupos experimentais (n=16): G1-adesivo convencional Magic Bond (Vigodent) e G2- adesivo autocondicionante AdheSE DC Activator (Ivoclar Vivadent). A área de adesão foi delimitada em 4mm de diâmetro, e o sistema adesivo, aplicado de acordo com as recomendações do fabricante. Em seguida, um de cilindro de resina composta de 2x2mm (diâmetro x altura) foi confeccionado por placa. As amostras foram armazenadas em soro fisiológico por 2 dias, VG a 37°C e submetidas a ensaio mecânico de resistência de união ao cisalhamento (0,5mm/min - TIRAtest 2420). Foi utilizada estatística descritiva e teste t de Student (5%). Resultados: o adesivo Magic Bond (11,2 ± 1,9) apresentou maior média de resistência de união que o adesivo AdheSE DC Activator (4,4 ± 1,5). Conclusão: os dados sugerem que a resistência de união ao esmalte bovino é maior nos sistemas adesivos convencionais que nos autocondicionantes.

Objective: This study evaluated the shear bond strength of two adhesive systems, one etch-and-rinse adhesive and one self-etching adhesive, in bovine tooth enamel. Methods: Thirty-two plates of bovine enamel (16mm2) were fabricated and randomly divided into two experimental groups (n=16): G1- etch-and-rinse adhesive Magic Bond (Vigodent) and G2- self-etching adhesive AdheSE DC Activator (Ivoclar Vivadent). The adhesion area was enclosed in 4mm of diameter and adhesive system applied according to the manufacturer's recommendations. Then a cylinder of composite resin (2mm diameter x 2mm height) was made by the plate. The samples were stored in saline solution for 2 days at 37°C and subjected to mechanical testing of shear bond strength (0,5mm/min - TIRAtest 2420). Was used descriptive statistics and Student's t test (5%). Results: Magic Bond (11.2 ± 1.9) showed higher mean strength than AdheSE DC Activator (4.4 ± 1.5). Conclusion: The data suggest that the bond strength to bovine enamel is higher in etch-and-rinse adhesives than in self-etching adhesives.