ABSTRACT: Aim: To compare the hydraulic conductance of human dentin disks which have been treated with an adhesive by operators of different genders and by active or passive modes of application. 60 third molars of healthy adults were included in resin blocks. These were cut to obtain 60 dentin disks of 1mm +/- 0.1 mm thick. Group 1 and 2, the adhesive was applied by 15 male operators passively (group 1) and vigorously (group 2). Groups 3 and 4, the adhesive was applied by 15 female operators passively (group 3) and vigorously (group 4). The flow rate was measured with a diffusion chamber and the hydraulic conductance of the disks was determined. Results: Mean for hydraulic conductance of each group was: 1 (0.01752), 2 (0.00355), 3 (0.01215), 4 (0.00877) in μl/minxcm2. There was statistically significant difference in the hydraulic conductance between experimental and control groups. There was no difference in dentin hydraulic conductance between genders. There was statistically significant difference in hydraulic conductance between the different modes of application. There was a moderate association between the pressure exerted when applying the adhesive and the values of dentin hydraulic conductance in vitro.

Resumo Ultimamente, o foco da Odontologia deslocou-se para uma "odontologia estética", em que os pacientes se preocupam em conseguir uma aparência melhor para seus dentes. O branqueamento vital é uma técnica com resultados imediatos que melhora aparência e auto-estima do paciente. O objetivo deste estudo foi detectar características de personalidade definidas pelo Índice Millon de Estilos de Personalidade de pessoas que buscaram branqueamento dental e correlacioná-las com a satisfação com o tratamento. Foram incluídos 40 participantes que preencheram o formulário do Índice Millon de Estilos de Personalidade antes do tratamento. A expectative sobre o branqueamento dental foi quantificada com valores de 1 a 5. Os pacientes foram tratados com agente branqueador de acordo com as instruções do fabricante. Uma semana depois o tratamento, a satisfação do paciente foi quantificada com valores de 1 a 5. Foram determinados as características predominantes. Os valores da expectativa e da satisfação foram correlacionados com cada escala de personalidade apresentada através do teste de Spearman Rho. Dez escalas prevaleceram sobre a sua contrapartida. A mediana das expectativas foi 2 e das satisfações foi 4. O valor de uma característica apenas (extraversão) apresentou correlação estatisticamente significante com a satisfação do paciente. Os pacientes que buscam o branqueamento dental parecem ter características comuns de personalidade. Quase todos queriam conseguir uma mudança moderada na cor dos dentes e o resultado do tratamento foi geralmente satisfatório.

Abstract In the last years the focus in dentistry has shifted to an "esthetic dentistry" approach, where patients are concerned about reaching a better look of their teeth. Vital tooth bleaching is a technique with immediate results, which improves the appearance and patient's self-esteem. The aim of this study was to recognize personality characteristics determined by the Millon Index of Personality Styles of participants looking for tooth bleaching and to correlate them to satisfaction with the treatment. Forty participants were included and filled out the Millon Index of Personality Styles form before treatment. Expectation about tooth bleaching was quantified from 1 to 5. Patients were treated with bleaching agent according to manufacturer's directions. One week after treatment, the patient's satisfaction was quantified from 1 to 5. Prevailing personality characteristics were determined. Expectations and satisfaction values of all patients were correlated with each of the presented personality scales by Spearman Rho test. Ten scales prevailed over their counterpart. Median of patient's expectation was 2 and satisfaction 4. Only the score of a single characteristic (extraversing) showed statistically significant correlation with patient satisfaction. Patients looking for tooth bleaching treatment seem to have common personality characteristics. Almost all of them wanted to achieve a moderate change in teeth color and the result of the treatment was usually satisfactory

RESUMEN. Introducción: el objetivo de esta revisión es analizar los resultados de las diferentes alternativas que presenta la literatura para incrementar la longevidad de las restauraciones con base a resinas compuestas. Métodos: fueron revisadas las bibliografías en la base de datos EBSCO (Elton B Stephens Company), en idioma inglés bajo los siguientes acrónimos " composite repair bond strengh"; "restorations sealing"; composite restorations longevity; "restorations refurbishment"; "composite bond estrategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength";" multiple layer dentin bond strength"; and "dentin adhesive evaporation bond strength". Se examinan los resultados clínicos y de laboratorio de reparación, sellado y remodelado de restauraciones defectuosas, además de las mejoras en la impregnación de las superficies adhesivas, la resistencia de los polímeros adhesivos y los avances en el aumento de la resistencia a la degradación hidrolítica del colágeno. Resultados: la reparación, sellado y remodelado de restauraciones defectuosas permite la preservación de estructura dentaria sana, reducción del potencial daño a la pulpa dental y reducción del dolor operatorio, la mayoría de las veces efectuado sin uso de anestésicos. Nuevas técnicas para el manejo de la adhesión proporcionan incremento en la longevidad de los procedimientos adhesivos. Conclusiones: la reparación, remodelado y sellado de resinas compuestas defectuosas, incrementa la longevidad de las restauraciones y de los dientes restaurados con la aplicación de técnicas de odontología mínimamente invasiva. Adicionalmente otras metodologías, tales como mejoras en la impregnación de las superficies adhesivas, aumento de la resistencia de los polímeros adhesivos e incremento de la resistencia a la degradación hidrolítica del colágeno constituyen promisorios avances que modifican el manejo de las técnicas adhesivas, que permitirá ofrecer tratamientos restauradores de mayor longevidad a la población.

ABSTRACT. Introduction: the goal of this literature review is to analyze the findings included in the literature concerning different alternatives to increase longevity of resin-based composite restorations and their adhesive bond. Methods: bibliographies in the EBSCO database (Elton B Stephens Company) were reviewed using the following key words: "composite repair bond strength"; "restorations sealing"; composite restorations longevity"; "restorations refurbishment"; "composite bond strategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength"; "multiple layer dentin bond strength", and "dentin adhesive evaporation bond strength". Clinical and laboratory results were analyzed in terms of repairing, sealing, and refurbishing defective restorations, in addition to improvements in impregnation of adhesive surfaces, resistance of adhesive polymers, and the progress recently made concerning resistance to hydrolytic collagen degradation. Results: repairing, sealing, or refurbishing defective restorations allow keeping tooth structure healthy, reducing potential damage to dental pulp, as well as operatory pain, often caused without anesthetics. New bonding management techniques provide adhesive procedures with increased longevity. Conclusions: repairing, refurbishing, or sealing defective composite resins increase the longevity of restorations and restored teeth by using minimally invasive dental techniques. Other methods, such as improving impregnation of adhesive surfaces, increasing adhesive polymers strength, and hydrolytic degradation of collagen are promising advances that modify the management of bonding techniques, providing patients with restorative treatments of increased longevity.

INTRODUCCIÓN: se utilizó un modelo in vitro, para medir la conductancia hidráulica en discos de dentina humana, tratados con ácido oxálico por 15, 30 o 60 s y la mantención del efecto oclusivo, medido a los 7 y 14 días post aplicación. MÉTODOS: 45 discos dentinarios de 1mm de grosor fueron obtenidos de terceros molares humanos libres de caries, en inoclusión, de pacientes entre 16 a 30 años de edad. Los discos fueron divididos en tres grupos de estudio (n = 15), dependiendo del tiempo de aplicación de una solución comercial de desensibilizante dentinario (DD) a base de oxalato (BisBlock®), que contiene < 5% ácido oxálico pH 1,5-1,8: grupo A aplicación del agente por 15 s, grupo B aplicación por 30 s y grupo C por 60 s. La conductancia hidráulica de cada disco fue calculada posterior al grabado ácido, lo que corresponde a la máxima permeabilidad de dicho disco (100%), inmediatamente tras la aplicación del ácido oxálico y tras siete y 14 días de mantención en suero fisiológico. El análisis estadístico se hizo mediante test de ANOVA y post hoc de Games-Howell. RESULTADOS:35,46 ± 23,41% para el grupo A, 36,34 ± 15,88% para el grupo B y 24,99 ± 14,99% para el grupo C, por lo que la utilización de DD por 15, 30 ó 60 s generó una disminución en la permeabilidad que fue estadísticamente significativa (p ? 0,05). CONCLUSIONES:el DD fue eficaz en reducir la conductancia hidráulica independiente del tiempo de aplicación, siendo esta reducción sólo temporal, ya que tras siete días la permeabilidad retorna a valores cercanos a los iniciales.

Applying self-etching dental adhesives containing 10-MDP overcomes the resistance to biodegradation of the adhesive interface of traditional total etch. The mechanism of action is based on the formation of multiple nano-layers of calcium and two molecules of 10-MDP on the dentin surface. These multiple layers of 3.5 nm protect the collagen fibers from hydrolysis phenomenon. The nano-layer explains its high stability and bond strength over time, tested both by clinical and laboratory studies. Hydroxyapatite interaction occurs with acids of low pH, but are higher than traditional, thus increasing the need to recommend the previous selective etching of the enamel. The use of MDP allows a change of philosophy from the total-etch adhesive to adhesive integration of the dentin.

La aplicación de adhesivos dentarios autograbantes que contienen 10-metacriloxidecilfosfato dihidrogenado supera la resistencia a la biodegradación de la interfase adhesiva de los sistemas tradicionales de grabado total. El mecanismo de acción se basa en la formación de múltiples nanocapas de calcio unido a 2 moléculas 10-metacriloxidecilfosfato dihidrogenado sobre la dentina; estas múltiples capas de 3,5 nm son las que protegerían las fibras colágenas del fenómeno de hidrólisis. Las nanocapas explicarían su alta estabilidad en el tiempo y la fortaleza de la unión, probadas tanto en estudios clínicos como de laboratorio. La interacción con la hidroxiapatita sucede con ácidos de pH bajos, pero mayores que los tradicionales, por lo que surge la necesidad de recomendar el grabado selectivo previo del esmalte. El uso de metacriloxidecilfosfato dihidrogenado permite el cambio de filosofía adhesiva desde el grabado total a la integración adhesiva de la dentina.

The aim of this study was to compare ex vivo filtration rate (hydraulic conductance) in human dentin discs mechanically treated with diamond and carbide burs of different grain size with or without acid etching. Method: 60 healthy third molars, recently extracted from patients aged 18-30 years, were cleaned, disinfected (0.1% thymol) and embedded in epoxy resin blocks. Dentin discs were obtained by cutting the occlusal surface with cylindrical rotary instruments, forming nine groups containing 12 specimens each: 1: fine grain (FG); 2: medium grain (MG); 3: coarse grain (CG); 4: carbide (C) burs; 5: FG with acid etching (AE); 6: MG with AE; 7: CG with AE; 8: C with AE; 9: only AE. Hydraulic conductance was determined in the experimental model under constant pressure of 200mm H2O. No difference in hydraulic conductance was observed among dentin discs treated with different types of burs (p=0.5). Differences were found in the hydraulic conductance of etched and non-etched dentin discs (p < 0.001). The type of mechanical bur treatment does not affect dentin hydraulic conductance. Acid etching significantly increases dentin hydraulic conductance.

El objetivo de este estudio fue comparar la tasa de filtracion ex vivo (conductancia hidraulica) en discos de dentina humana tratados mecanicamente con fresas de diamante de diferente granulometria y carbide con o sin grabado acido. Metodo: 60 terceros molares sanos recientemente extraidos de pacientes entre 18-30 anos, fueron limpiados, desinfectados (0.1% timol) e incluidos en bloques de resina epoxica. Los discos de dentina se obtuvieron mediante la reduccion de la superficie oclusal con instrumentos rotativos cilindricos, formando los siguientes nueve grupos de 12 muestras c/u: 1: grano fino (FG); 2: grano medio (MG); 3: grano grueso (CG); 4: fresas de carburotungsteno (C); 5: FG con grabado acido (AO); 6: GM con AO; 7: GG con AO; 8: C con AO; 9: solo grabado acido. Se determino la conductancia hidraulica en el modelo experimental bajo presion constante de 200 mm de altura de H2O. No se observaron diferencias entre la conductancia hidraulica entre los diferentes tipos de fresas (p = 0,5).Se encontraron diferencias en la conductancia hidraulica de discos de dentina con y sin grabado acido (p < 0,001). El tipo de fresa no afecta la conductacia hidraulica dentinaria. El grabado acido aumenta significativamente la conductacia hidraulica dentinaria.