Microabrasion in tooth enamel discoloration defects: three cases with long-term follow-ups

Superficial irregularities and certain intrinsic stains on the dental enamel surfaces can be resolved by enamel microabrasion, however, treatment for such defects need to be confined to the outermost regions of the enamel surface. Dental bleaching and resin-based composite repair are also often useful for certain situations for tooth color corrections. This article presented and discussed the indications and limitations of enamel microabrasion treatment. Three case reports treated by enamel microabrasion were also presented after 11, 20 and 23 years of follow-ups224347354sem informaçã

Microabrasion in tooth enamel discoloration defects: three cases with long-term follow-ups

Superficial irregularities and certain intrinsic stains on the dental enamel surfaces can be resolved by enamel microabrasion, however, treatment for such defects need to be confined to the outermost regions of the enamel surface. Dental bleaching and resin-based composite repair are also often useful for certain situations for tooth color corrections. This article presented and discussed the indications and limitations of enamel microabrasion treatment. Three case reports treated by enamel microabrasion were also presented after 11, 20 and 23 years of follow-ups

Conservative reconstruction of the smile by orthodontic, bleaching, and restorative procedures

The following is a clinical case report of a patient whose chief complaint was the presence of generalized spacing in the maxillary anterior segment following orthodontic treatment. After meticulous clinical analyses and discussions of the clinical procedures to be adopted, dental bleaching was performed in both arches with 10% hydrogen peroxide (Opalescence Trèswhite Supreme 10% Hydrogen Peroxide - Ultradent Products, Inc., South Jordan, USA) after the conclusion and stabilization of orthodontic treatment. Then, the orthodontic appliance was removed and the diastemas in the maxillary anterior teeth were closed with Amelogen Plus (Ultradent Products, Inc., South Jordan, USA) resin composite. It was observed that the association of orthodontic, bleaching, and restorative procedures was capable of restoring dental shape, function, and esthetics, allowing the patient to smile without hesitation

Microabrasion in tooth enamel discoloration defects: three cases with long-term follow-ups

Superficial irregularities and certain intrinsic stains on the dental enamel surfaces can be resolved by enamel microabrasion, however, treatment for such defects need to be confined to the outermost regions of the enamel surface. Dental bleaching and resin-based composite repair are also often useful for certain situations for tooth color corrections. This article presented and discussed the indications and limitations of enamel microabrasion treatment. Three case reports treated by enamel microabrasion were also presented after 11, 20 and 23 years of follow-ups

Building a National IoT Plan: Policy Recommendations and the Case of Brazil

The Internet of Things (“IoT”) is an expression that refers to a whole set of new services and devices that includes at least three fundamental aspects: connectivity, use of sensors or actuators, and computational capacity for data processing and storage. The Internet of Things goes beyond connecting objects to each other; it also gives them the power to process data (thereby making them "smart"). For developing countries such as Brazil, the opportunities offered by the Internet of Things can compensate for shortcomings in infrastructure and services, and can improve innovation, quality of life, productivity, and even the economic complexity of our basket of export products. However, the way in which each country will seize this opportunity will depend on its specific aspirations and strategies. The broader economic, social, political, and legal context of the country should be considered, as well as the local development of information and communication technologies. For this reason, the National Bank for Economic and Social Development (BNDES), in partnership with the Ministry of Science, Technology, Innovation and Communications (MCTIC), has commissioned this study, "Internet of Things: An Action Plan for Brazil." This study, mapped by a consortium comprised by McKinsey & Company, the CPqD Foundation, and Pereira Neto | Macedo Law Firm, outlines the local technological and economic challenges related to the topic, as well as well as how to address legal issues inherent to the development of IoT in Brazil

Influência da espessura da cerâmica e do modo de ativação na resistência à flexão de cimentos resinosos

O objetivo deste estudo foi avaliar a influência da espessura da cerâmica e do modo de ativação (fotoativação, ativação dual) na resistência à flexão do cimento resinoso. Amostras do cimento resinoso Varfolink II (Ivoclar vivadent) no formato de barras retangulares (6,5 mm de comprimento x 2 mm largura x 1 mm de espessura) foram confeccionadas testando dois modos de polimerização: fotoativação e ativação dual. Discos da cerâmica IPS Empress Esthetic (Ivoclar vivadent) com 8 mm de diâmetro, nas espessuras de 0,7, 1,4 e 2,0 mm, foram obtidos e interpostos entre o cimento resinoso e a fonte de luz LED-UltraLume 5 (Ultradent). Após a confecção, as amostras foram armazenadas em água destilada a 37°C, por 24 horas. A seguir, foram submetidas ao ensaio de resistência à flexão de 3 pontos a velocidade de 0,5 mm/min, em máquina de ensaios mecânicos (Instron). Os valores de resistência à flexão foram calculados em MPa e submetidos à Análise de Variância e ao teste de Tukey (5%) e mostraram que a forma de ativação do cimento resinoso Variolink II (fotoativada ou com presa dual) não influenciou os valores de resistência à flexão. A espessura da cerâmica não influenciou a polimerização do cimento resinoso para os dois modos de ativação

Evaluation of heat treatments and hydrofluoric acid concentrations on the surface morphology and bond strength to lithium disilicate reinforced glass ceramic

Orientador: Luis Roberto Marcondes MartinsTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O presente estudo avaliou a influência do prévio tratamento térmico (PTT) e das diferentes concentrações do ácido hidrofluorídrico (AF) nas características de união entre a cerâmica vítrea reforçada por dissilicato de lítio (EMX) e cimento resinoso. O estudo foi dividido em 3 capítulos: Capítulo 1) avaliação de diferentes concentrações de AF (1%, 2,5%, 5%, 7,5% e 10%) e suas interações com o PTT (grupo controle ¿ sem tratamento térmico prévio; AF previamente aquecido ¿ 70 °C; superfície do EMX previamente aquecido ¿ 85 °C; combinação do AF e EMX previamente aquecidos) na morfologia da superfície do EMX (n=1) e resistência de união pelo microcisalhamento (?CLM) (n=12) entre EMX e cimento resinoso (?=1 mm); Capítulo 2) avaliação de diferentes concentrações de AF (5% e 10%) e suas interações com o PTT (descritos no Capítulo 1) na morfologia da superfície do EMX (n=1) e ?CLM (n=12) entre EMX e cimento resinoso (matriz Tygon, ?=0,8 mm); Capítulo 3) avaliação de diferentes concentrações de AF (5% e 10%) e suas interações com o PTT (descritos no Capítulo 1) na morfologia da superfície do EMX (n=1) e resistência de união pela microtração (?T) (palitos com área de 1 mm2) (n=10) após 24 horas ou 18 meses de armazenamento em água. Após condicionamento durante 20 segundos, aplicou-se silano seguido de uma fina camada de adesivo. No capítulo 1, o cimento resinoso fotoativado foi inserido em 3 espaços com formatos cilíndricos a partir de matrizes pré-fabricadas e polimerizados por 20 segundos. Já no Capítulo 2, 5 matrizes Tygon foram posicionadas sobre a superfície do EMX e o mesmo cimento resinoso fotoativado foi inserido e polimerizado por 20 segundos. No capítulo 3, o EMX condicionado foi cimentado à um bloco de resina composta por meio de um cimento resinoso dual. A análise da morfologia do EMX após condicionamento apresentou o mesmo comportamento nos 3 capítulos: AF 10% apresentou maior grau de condicionamento e o tratamento térmico potencializou o condicionamento das menores concentrações de AF (1%, 2,5% e 5%). Nos grupos controle do Capítulo 1, 1%, 2,5% e 5% resultaram nos menores valores de ?CLM (p0.05). Da mesma forma, os resultados de ?CLM do Capítulo 2 mostraram um aumento nos valores de ?CLM quando o PTT foi aplicado para o grupo condicionado com AF 5% (p0.05). Tanto a concentração do AF, quanto o PTT, influenciou nas características de união entre o EMX e cimento resinoso, de modo que menores concentrações submetidas ao PTT se mostraram tão eficazes quanto maiores concentrações de AFAbstract: The present study evaluated the influence of previous thermal treatment (PTT) of different hydrofluoric acid (HF) concentrations on the bonding characteristics between a reinforced lithium disilicate glass ceramic (EMX) and resin cement. The study was divided into 3 chapters: Chapter 1) evaluation of different HF concentrations (1%, 2.5%, 5%, 7.5% and 10%) and their interaction with PTT (control group ¿ no PTT; previously heated HF ¿ 70°C; previously heated EMX surface ¿ 85 °C; and the combination of previously heated HF and EMX) on the EMX surface morphology (n=1) and microshear bond strength (?SBS, ?=1 mm) (n=12) between EMX and resin cement; Chapter 2) evaluation of different HF concentrations (5% and 10%) and their interaction with PTT (previously described in Chapter 1) on the EMX surface morphology (n=1) and microshear bond strength (?SBS, Tygon matrices of ?= 0.8 mm) (n=12) between EMX and resin cement; Chapter 3) evaluation of different HF concentrations (5% and 10%) and their interaction with PTT (previously described in Chapter 1) on the EMX surface morphology (n=1) and microtensile bond strength (?TBS, sticks with 1 mm2) (n=10) between EMX and resin cement at 24-hour and after 18 months of water storage. After etching, silane and a thin bonding agent were applied. In Chapter 1, resin cement was inserted into three cylinder-shaped orifices from pre-fabricated matrices and lightcured for 20 seconds. In Chapter 2, five Tygon tubes as matrices were positioned on the EMX surface and the same resin cement was inserted and lightcured for 20 seconds. In Chapter 3, the etched EMX was luted to a resin composite block via dual-cured resin cement. The etched surface morphology analysis revealed the same pattern in the three Chapters: 10% HF presented a higher conditioning effect and PTT enhanced the etching efficacy of lower HF concentrations (1%, 2.5% and 5%). For control groups in Chapter 1, 1%, 2.5% and 5% yielded lower ?SBS values (p0.05). Similarly, the ?SBS results of Chapter 2 showed an increase on the ?SBS values after PTT on groups etched with 5% HF (p0.05). Both HF concentrations and PTT have influenced on the bonding characteristics between EMX and resin cements, so that lower HF concentrations submitted to PTT were shown to be as effective as higher HF concentrationsDoutoradoDentísticaDoutor em Clínica Odontológica2013/26573-7140696/2013-0FAPESPCNP

Bond strenght between dental ceramic-resin cement and surface/interface morphology of glass ceramics etched with different hydrofluoric acid concentrations

Orientador: Lourenço Correr SobrinhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo neste estudo foi avaliar a influência de diferentes concentrações do ácido fluorídrico (AF) na morfologia da superfície/interface, assim como a resistência de união ao microcisalhamento de dois tipos de cerâmica vítrea: (1) IPS Empress Esthetic (EST), (Ivoclar Vivadent) e (2) IPS e.max Press (EMX), (Ivoclar Vivadent), unidas ao cimento resinoso (Variolink II, Ivoclar-Vivadent), com ou sem aplicação do adesivo (Ad) após a aplicação do silano. Blocos cerâmicos com 8 × 8 × 2 mm de espessura foram separados em 12 grupos, totalizando 24 grupos, de acordo com as concentrações do ácido fluorídrico: 1%, 2,5%, 5%, 7,5%, 10% e 15%. O tempo de condicionamento para a cerâmica EST foi 60 segundos e para EMX, 20 segundos. Todos os blocos foram silanizados após o condicionamento ácido e a sigla 'Ad' nos grupos designados recebeu a aplicação de uma camada de adesivo após a aplicação do silano. Caracterização dos padrões de condicionamento e interfaces de união foram conduzidas pela análise em MEV. Para o ensaio de microcisalhamento, cilindros de cimento resinoso foram confeccionados sobre a superfície da cerâmica condicionada, fotoativados durante 40 segundos e armazenados durante 24 horas em água destilada a 37°C. Os dados foram submetidos à Análise de Variância de 3 fatores e ao teste de Tukey (p<0,05). As imagens de MEV mostraram pobre condicionamento quando utilizado a concentração de 1%, para EST e EMX. HF2,5% mostrou grande remanescente de fase vítrea e ranhuras pouco profundas na superfície das cerâmicas. Padrões semelhantes de condicionamento foram encontrados para HF7,5% e HF10%. Canais profundos foram encontrados para HF15%. Espaços não preenchidos foram encontrados na interface de grupos que não receberam a aplicação do adesivo. O preenchimento desses espações foi encontrado quando se utilizou o adesivo, mostrando uma interface mais contínua e homogênea. Para o teste de microcisalhamento, os resultados não mostraram diferença estatística entre as cerâmicas EST e EMX. Grupos que receberam o adesivo mostraram valores estatisticamente maiores do que o grupo sem adesivo e HF10% e HF15% mostram valores estatisticamente maiores comparados ao HF1% e HF2,5%. Conclusão: A concentração do ácido fluorídrico influenciou na topografia da superfície e nos valores de resistência de união ao microcisalhamento. O adesivo resultou em maiores valores de união e mostrou-se capaz de criar uma interface mais homogênea, resultando em interfaces mais "entrelaçadas" e provavelmente essa característica pode fornecer interfaces mais confiáveisAbstract: The objective on this study was to evaluate the influence of hydrofluoric acid (HF) concentration on the surface/interface morphology, also the microshear bond strenght on two types of ceramic: (1) IPS Empress Esthetic (EST), (Ivoclar Vivadent), (2) IPS e.max Press (EMX), (Ivoclar Vivadent), bonded to a resin cement (Variolink II, Ivoclar-Vivadent), with or without application of an unfilled resin (UR) after silane application. Each type of ceramic blocks with 8 mm × 8mm × 2 mm in thickness were separated into 12 groups (n=6), totaling 24 groups, according to the hydrofluoric acid concentration: 1%, 2.5%, 5%, 7.5%, 10% and 15%. Etching time was fixed in 60 seconds for EST and 20 seconds for EMX. All the groups were silanated after etching and the acronym 'UR' on the designated groups received a layer of an unfilled resin after silane application. Characterization of the etching patterns and bonding interfaces was conducted by SEM. For the microshear bond test, resin cylinders were built on the etched ceramic surface, photoactivated during 40 seconds and stored in distilled water during 24 hours, 37°C, for later evaluation in a universal testing machine. The data were submitted to three-way ANOVA and Tukey's test (p<0.05). SEM images showed that poor etching was detected when using HF 1% on EST and EMX groups. HF 2.5% resulted in large remnants of vitreous phase and shallow grooves on ceramic surface. Similar etching patterns were detected for HF 7.5 and 10%. Deep channels were extensively observed on surfaces etched with HF 15%. Unfilled voids underlying the ceramic-resin cement interface were detected in groups that did not receive the application of the unfilled resin. Fully completion of the irregularities was detected using unfilled resin. Overall, when both silane and unfilled resin were applied, all groups generally showed more continuously and homogeneous interfaces. For microshear bond test, the results showed no statistical difference among EST and EMX. Groups with unfilled resin showed statistical higher microshear bond values than groups that did not received this treatment and HF10% and HF15% showed statistical higher values compared to HF1% and HF2.5%. Conclusion: Hydrofluoric acid concentration influenced the ceramic topography and microsher bond strength values. Unfilled resin seems to create more homogeneous interfaces and its application was able to infiltrate the unfilled voids beneath the ceramic-resin cement interface, resulting in more entangled interfaces and probably this feature could result in more reliable interfacesMestradoMateriais DentariosMestre em Materiais Dentário

Smile restoration through use of enamel microabrasion associated with tooth bleaching

Enamel microabrasion can eliminate enamel irregularities and discoloration defects, improving the appearance of teeth. This article presents the latest treatment protocol of enamel microabrasion to remove stains on the enamel surface. It has been verified that teeth submitted to microabrasion acquire a yellowish color because of the thinness of the remaining enamel, revealing the color of dentinal tissue to a greater degree. In these clinical conditions, correction of the color pattern of these teeth can be obtained with a considerable margin of clinical success using products containing carbamide peroxide in custom trays. Thus, patients can benefit from combined enamel microabrasion/tooth bleaching therapy, which yields attractive cosmetic results. Esthetics plays an important role in contemporary dentistry, especially because the media emphasizes beauty and health. Currently, in many countries, a smile is considered beautiful if it imitates a natural appearance, with clear, well-aligned teeth and defined anatomical shapes.1-3 Enamel microabrasion is one technique that can be used to correct discolored enamel. This technique has been elucidated and strongly advocated by Croll and Cavanaugh since 1986,4 and by other investigators1,2,5-13 who suggested mechanical removal of enamel stains using acidic substances in conjunction with abrasive agents. Enamel microabrasion is indicated to remove intrinsic stains of any color and of hard texture, and is contraindicated for extrinsic stains, dentinal stains, for patients with deficient labial seals, and in cases where there is no possibility to place a rubber dam adequately during the microabrasion procedure.1,2 It should be emphasized that enamel microabrasion causes a microreduction on the enamel surface,3,6,10 and, in some cases, teeth submitted to microabrasion may appear a darker or yellowish color because the thin remaining enamel surface can reveal some of the dentinal tissue color. In these situations, according to Haywood and Heymann in 1989,14 correction of the color pattern of teeth can be obtained through the use of whitening products containing carbamide peroxide in custom trays. A considerable margin of clinical success has been shown when diligence to at-home protocols is achieved by the patient and supervised by the professional.3 Considering these possibilities, this article presents the microabrasion technique for removal of stains on dental enamel, followed by tooth bleaching with carbamide peroxide and composite resin restoration, if required. - See more at: https://www.dentalaegis.com/cced/2011/04/smile-restoration-through-use-of-enamel-microbrasion-associated-with-tooth-bleaching#sthash.N6jz2Bwk.dpu