Influência da utilização de ácido glicólico e adesivos universais na qualidade da camada híbrida em restaurações adesivas: revisão de literatura / Influence of the use of glycolic acid and universal adhesives on the quality of the hybrid layer in adhesive restorations: literature review

A camada híbrida é definida pela zona de inter difusão do polímero do adesivo e o substrato dental. Os sistemas adesivos universais são materiais que foram criados com o intuito de substituir a estrutura dental que foi perdida a fim de diminuir essa área de interação adesiva e os espaços desmineralizados da dentina. O objetivo do seguinte estudo é realizar uma revisão de literatura acerca da influência dos adesivos universais e o uso do ácido glicólico como condicionante dental. Foi realizada uma busca na literatura atual, nas seguintes bases de dados: PubMed, Scielo, Medline e Google Acadêmico nos idiomas inglês e português usando os termos de pesquisa: "adhesive systems" AND "phosphoricacid" OR/AND "glycolicacid" OR/AND "hybridlayer" OR/AND "universal adhesive system". As pesquisas realizadas utilizando o ácido glicólico como agente condicionante dental demonstraram que a substância tem potencial e efetividade, diminuindo consideravelmente a região de fibras colágenas expostas para a fusão do adesivo universal. O ácido glicólico utilizado como agente condicionante de esmalte e dentina mostrou-se eficaz e promissor, tendo em vista que a camada híbrida se apresentou com menor espessura sem alterar a estrutura dentinária. Porém, faz-se necessário mais pesquisas utilizando o ácido glicólico juntamente com o sistema adesivo universal, por curto, médio e longo prazo.

The hybrid layeri s defined by the interdiffusion zone of the adhesive polymer and the dental substrate. Universal adhesive systems are materials that have been created with the aim of replacing the tooth structure that has been lost in order to reduce this area of adhesive interaction and the demineralized spaces of dentin. The aim of the following study is to perform a literature review on the influence of universal adhesives and the use of glycolic acid as a dental conditioning agent. A search was conducted in the current literature in the following databases: PubMed, Scielo, Medline and Google Scholar in English and Portuguese using the search terms: "adhesive systems" AND "phosphoric acid" AND "glycolic acid" AND "hybrid layer" OR "universal adhesive system". Research using glycolic acid as a dental conditioning agent has shown that the substance has potential and effectiveness, considerably reducing the region of collagen fibers exposed for the fusion of the universal adhesive. Glycolic acid used as a conditioning agent for enameland dent inproved to be effective and promising, considering that the hybrid layer was presented with less thickness without altering the dentin structure. However, further research his needed usinggly colic acid together with the universal adhesive system, for short, medium and long term.

Profile of depigmenting cosmetics and dermatological products on the market

The skin is the largest and most exposed organ of the human body, therefore subject to diseases and alteration of its appearance. Among these alterations, the cutaneous hyperchromia may be cited. Currently, the market offers numerous products with depigmenting action to the treatment of such disorders. The aim of this work was to analyze depigmenting products commercialized in establishments in the city of Bento Gonçalves (RS, Brazil) and websites of cosmetic companies. It was found 45 products with depigmenting action and, from these, 59 different active agents were identified. The main active compounds found were kojic acid, arbutin, ascorbic acid, hydroquinone and glycolic acid. Another observed data was that in 78% of the studied products the active substances were being used in combination. The most used vehicles were also studied as a reference to the use of sunscreen in the treatment of cutaneous hyperchromia. The present work had identified in the market a variety of products with depigmentation action and, because of this, it aims to serve as a reference to the healthcare professionals, especially at the prescribing moment, looking for the best results, with regards to treatment efficiency and safety.(AU)

Efficacy and safety of superficial chemical peeling in treatment of active acne vulgaris

Abstract: Acne vulgaris is an extremely common condition affecting the pilosebaceous unit of the skin and characterized by presence of comedones, papules, pustules, nodules, cysts, which might result in permanent scars. Acne vulgaris commonly involve adolescents and young age groups. Active acne vulgaris is usually associated with several complications like hyper or hypopigmentation, scar formation and skin disfigurement. Previous studies have targeted the efficiency and safety of local and systemic agents in the treatment of active acne vulgaris. Superficial chemical peeling is a skin-wounding procedure which might cause some potentially undesirable adverse events. This study was conducted to review the efficacy and safety of superficial chemical peeling in the treatment of active acne vulgaris. It is a structured review of an earlier seven articles meeting the inclusion and exclusion criteria. The clinical assessments were based on pretreatment and post-treatment comparisons and the role of superficial chemical peeling in reduction of papules, pustules and comedones in active acne vulgaris. This study showed that almost all patients tolerated well the chemical peeling procedures despite a mild discomfort, burning, irritation and erythema have been reported; also the incidence of major adverse events was very low and easily manageable. In conclusion, chemical peeling with glycolic acid is a well-tolerated and safe treatment modality in active acne vulgaris while salicylic acid peels is a more convenient for treatment of darker skin patients and it showed significant and earlier improvement than glycolic acid

Randomized clinical efficacy of superficial peeling with 85% lactic acid versus 70% glycolic acid / Estudo randomizado da eficacia clinica dos peelings superficiais de acido lactico 85% versus acido glicolico 70%

BACKGROUND: Peeling is a procedure which aims to accelerate the process of skin exfoliation. OBJECTIVES: Development of formulations containing lactic acid at 85% or glycolic acid at 70% and the evaluation of these formulations on clinical efficacy in reduction of fine wrinkles. METHODS: Preliminary stability tests were carried out and an in vivo study was performed with three groups with 9 representatives each. One was the control group, which used only sunscreen; another one used lactic acid+sunscreen, and the last group used acid glycolic+sunscreen. Clinical efficacy was assessed with a CCD color microscope, through the digitization of images before and after treatment. The applications were carried out by a dermatologist, once a mont h every 30 days, during 3 months. The area with wrinkles was calculated by planimetry point counting, in accordance with Mandarin-de-Lacerda. RESULTS: The formulations were stable in the visual and Ph evaluation. There was no improvement in the control group; for lactic acid, there was significant improvement after the second peeling application on the outer lateral area of the right eye and after the third application on the outer lateral area of the left eye. For the glycolic acid group, there was significant improvement in the outer lateral area of the left eye after the first application, and of the right eye region, after three applications. The formulations used must be kept under refrigeration and should be manipulated every 30 days. CONCLUSIONS: Both peelings were effective in reducing fine wrinkles of the outer lateral eye area after three applications (p≤0.05%). It was observed that peeling efficacy in the external-lateral region of one eye might be different compared with that in skin of the external-lateral region of the other eye, relative to the speed of skin improvement. .

FUNDAMENTOS: Peeling visa a acelerar o processo de esfoliação da pele. OBJETIVOS: Desenvolver formulações contendo ácido láctico a 85% ou ácido glicólico a 70% e avaliar sua eficácia clínica na redução de rugas finas. MÉTODOS: Testes preliminares foram efetuados e estudo in vivo foi realizado em três grupos com nove representantes cada, separados de forma randomizada. Um grupo foi controle, utilizando apenas fotoprotetor; outro utilizou ácido láctico e fotoprotetor; o último usou ácido glicólico e fotoprotetor. Para eficácia clínica, empregou-se microscópio CCD color, digitalizando-se as imagens do pré e do pós-tratamento. As aplicações foram realizadas por médica dermatologista uma vez por mês, a cada 30 dias, durante três meses. A área com traços de ruga foi calculada pela planimetria por contagem de pontos. RESULTADOS: As formulações foram estáveis na avaliação visual e de pH. Não houve melhora no grupo controle; para o grupo do ácido láctico, houve melhora significativa após a segunda aplicação do peeling na região lateral externa do olho direito e após a terceira aplicação na região lateral externa olho esquerdo. Para o grupo do ácido glicólico, houve melhora significativa na região lateral externa olho esquerdo após a primeira aplicação e, depois de três aplicações, na região lateral externa do olho direito. As formulações magistrais empregadas no estudo devem ser mantidas sob refrigeração e manipuladas a cada 30 dias. CONCLUSÕES: Tanto o peeling de ácido láctico quanto o de ácido glicólico foram eficazes na diminuição de rugas finas da região lateral externa dos olhos após ...

Formulation and in vitro evaluation of fast dissolving tablets of metoprolol tartrate

The demand for fast dissolving tablets has been growing during the last decade, especially for elderly and children who have swallowing difficulties. In the present work, fast dissolving tablets of metoprolol tartrate, were prepared using sodium starch glycolate, sodium croscarmellose and crospovidone as superdisintegrants, by the direct compression method. The tablets prepared were evaluated for various parameters including weight variation, hardness, friability, in vitro dispersion time, drug-polymer interaction, drug content water absorption ratio, wetting time, in vitro drug release, FTIR and DSC studies. The tablets prepared by the direct compression method had a weight variation in the range of 145 mg to 152 mg, which is below ± 7.5%, a hardness of 3.6 kg/cm² to 4.5 kg/cm², percentage friability of 0.46% to 0.73%, in vitro dispersion time of 18 s to 125 s, drug content uniformity of between 98.12% and 100.03%, a water absorption ratio of 67% to 87%, wetting time of 32 sec. to 64 sec., and an in vitro drug release of 53.92% - 98.82% within 15 min. The IR spectral analysis and DSC study showed no drug interaction with formulation additives of the tablet, and the formulations indicated no significant changes in hardness, friability, drug content or in vitro drug release. Fast dissolving tablets of metoprolol tartrate have enhanced dissolution and will lead to improved bioavailability and more effective therapy.

A exigência por comprimidos de dissolução rápida aumentou durante a última década, especialmente para idosos e crianças, com dificuldades de deglutição . No presente trabalho prepararam-se, pelo método de compressão direta, comprimidos de tartarato de metoprolol de rápida dissolução, utilizando glicolato sódico de amido, croscarmellose sódica e crospovidona como superdisintegrantes. Os comprimidos preparados foram avaliados em relação a diferentes parâmetros, como variação de peso, dureza, friabilidade, tempo de dispersão in vitro, interação fármaco-polímero, taxa de absorção de água pelo fármaco, tempo de umedecimento, liberação do fármaco in vitro,, FTIR e estudos de DSC. Os comprimidos preparados por compressão direta apresentaram variação de peso de 145 mg a 152 mg, abaixo de ±7,5%, dureza de 3,6 kg/cm² a 4,5 kg/cm² , porcentagem de friabilidade de 0,46% a 0,73%, tempo de dispersão in vitro de 18 s a 125 s, uniformidade de conteúdo de fármaco entre 98,12% e 100,03%, taxa de absorção de água de 67% a 87%, tempo de umidificaçãode 32 s a 64 s liberação do fármaco in vitro entre 53,92% e 98,82%, em 15 min. A análise no IV e de DSC mostrou que não houve interação de fármacos com os aditivos de formulação do comprimido e as formulações indicaram que não houve mudança significativa na dureza, friabilidade, s uniformidade de conteúdo de fármaco e na liberação do fármaco in vitro. Os comprimidos de liberação rápida apresentaram aumento na dissolução de tartarato metoprolol e conduzem à melhoria dabiodisponibilidade e à terapia eficaz.

Biocompatibilidade e biodegradabilidade de micropartículas de poli-lactato-co-glicolato na ceratite infecciosa em coelhos / Biocompatibility and biodegradability of poly-latic-co-glycolatic microparticles in the infectious keratitis in rabbits

Avaliaram-se a biocompatibilidade e a biodegradabilidade do sistema de liberação controlada de poli-lactato-co-glicolato (PLGA) no tratamento com ciprofloxacina das ceratites por Staphylococcus aureus em coelhos. Foram utilizados 20 coelhos, distribuídos em quatro grupos (G). Os animais dos G1, G3 e G4 foram inoculados com 2,5µL da bactéria - 108UFC, no estroma corneano. Os do G2 não receberam a aplicação do inóculo. O tratamento foi realizado com solução salina básica para os animais do G1, micropartículas de PLGA contendo ciprofloxacina nos animais dos G2 e G4 e colírio de ciprofloxacina naqueles do G3. Suabe e biópsia da superfície ocular foram coletados para cultura. Apenas um animal do G1 apresentou cultura positiva para S. aureus. Exame histológico revelou a presença bacteriana em todos os animais do G1 e em dois animais do G3. Também foi constatada reação inflamatória no local da aplicação do sistema de liberação controlada. O tratamento com micropartículas de PLGA foi eficiente no tratamento de ceratites bacterianas, ao eliminar por completo a presença do S. aureus, mas entretanto não foi completamente biocompatível e biodegradável após cinco dias.

The biocompatibility and biodegradability of the controlled delivery system of Poly-Latic-Co-Glucolatic (PLGA) in the treatment of Staphylococcus aureus keratitis with ciprofloxacin in rabbits were evaluated. Twenty rabbits divided into four groups (G) were used. G1, G3 and G4 animals were inoculated with bacterial 2.5µL (108CFU) in the corneal stroma, and G2 animals did not receive the application of inoculum. The treatment was performed with basic saline solution in G1 rabbits, micro particles of PLGA containing ciprofloxacin in G2 and G4 animals, and ciprofloxacin eye drops in G3 rabbits. Swab and biopsy of the ocular surface were collected for culture. Only one animal in G1 had positive culture for S. aureus in the processed material. Histological examination showed a bacterial presence in all animals in G1 and two animals in G3. Inflammatory reaction was noted at the application site of the controlled release. Data analysis showed that treatment with micro particles of PLGA was effective in treating bacterial keratitis, completely eliminating the presence of S. aureus, but it was not being completely biocompatible and biodegradable after five days.

Uso de malla reabsorbible en traumatismo esplénico en ratas / Use of reabsorbing mesh in rats splenic trauma

Objetivo: Determinar si el empleo de malla reabsorbible cohibe la hemorragia y evita la exéresis del bazo en el traumatismo abdominal. Diseño: Estudio experimental. Lugar: Servicio de Técnica Quirúrgica y Cirugía Experimental, Universidad Nacional Mayor de San Marcos, y Servicio de Cirugía Experimental, Hospital del Niño, Lima, Perú. Materiales: Malla reabsorbible (ácido poliglicólico), ratas, anestésicos, instrumentos de cirugía menor, material para fijación anatomopatológico. Intervenciones: Bajo anestesia general, se laparotomizó a la rata con incisión mediana, para exponer el bazo, al cual se produjo lesiones de 1º, 2º y 3º grados; luego, se cubrió con la malla reabsorbible, fijando alrededor con catgut 3/0, presionando hasta cohibir la hemorragia; enseguida se cerró cavidad abdominal con puntos de vicryl 3/0. Se evaluó clínicamente a las 24, 48 y 72 horas posquirúrgicas, para observar la supervivencia; luego, relaparotomía al azar, a los 15 y 30 días y 3 meses, para ver presencia de adherencias y tiempo de reabsorción de la malla. Principales medidas de resultados: Supervivencia, adherencias posquirúrgicas y reabsorción de la malla. Resultados: De las 60 ratas con lesiones de 1º, 2º y 3º grados, se observó una supervivencia de 97 por ciento (58 ratas) y 3 por ciento murieron (2 ratas: una rata con lesión de 1º grado a las 24 horas por agresión y otra con lesión de 3º grado a las 72 horas que a la necropsia se encontró microabscesos en omento e hígado). A los 15 y 30 días de relaparotomía, se observó presencia de adherencias intraabdominales y, a los 3 meses, reabsorción total de la malla. Conclusiones: La malla reabsorbible (ácido poliglicólico) es un material que, aparte de cohibir la hemorragia, evita la esplenectomía, conservando el bazo en casos de hemorragia por traumatismo abdominal.

Objective: To determine if use of reabsorbing mesh stops hemorrhage and avoids spleen removal in abdominal trauma. Design: Experimental study. Setting: Experimental Surgery Service, of both UNMSM and ChildrenÆs Hospital. Materials: Reabsorbing mesh (polyglycolic acid), rats, anesthesia, minor surgery equipment, materials for anatomical tissues. Interventions: Under general anesthesia rats were opened by midline incision to expose the spleen, which was injured in 1st, 2nd and 3rd degrees, then covered with reabsorbing mesh, fixing with catgut 3/0 and pressing until bleeding was restrained; then abdominal cavity was closed with vicryl 3/0. Clinical evaluation was done at 24, 48 and 72 hours post-surgery to observe survival, then re-opened randomly at 15, 30 days and 3 months to see the presence of adhesions and mesh reabsorption. Main outcome measures: Survival, adhesions, mesh reabsorption. Results: From the 60 rats with 1st, 2nd, and 3rd degree lesions 97 per cent survived (58 rats) and 3 per cent died (2 rats: one rat with 1º degree injury died at 24 hours because of aggression from another rat and another rat with 3º degree injury died 72 hours post op and at necropsy showed micro abscesses in mesentery and liver). At 15 and 30 days we observed intra-abdominal adhesions, and at 3 months total reabsorption of the mesh. Conclusions: Reabsorbing mesh (polyglycolic acid) is a material that restrains bleeding and avoids spleen extraction in abdominal trauma bleeding.

Experiencia clínica de una formulación a base de Zincadone A® en pacientes chilenas con diagnóstico clínico de acné inflamatorio leve / Clinical efficacy of a formulation with Zincadone A® in chilean patients with mild inflammatory acne

Se relizó un estudio abierto, de tipo prospectivo, para evaluar la eficacia de una formulación a base de Zincadone A® en 34 mujeres portadoras de acné inflamatorio leve durante un período de 12 semanas. Hubo una mejoría significativa en cada uno de los parámetros medidos. Los efectos adversos se limitaron a la aparición de prurito en un 3 por ciento de las pacientes. Se confirman la eficacia y seguridad de la formulación en el tratamiento del acné inflamatorio leve.