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Objective: Evaluate and compare the antimicrobial efficacy of four different commercially available children’s toothpastes on bacteria growth inhibition from oral microbiota of young children. Material and Method: The toothpastes tested contained: 1100 ppm sodium fluoride, xylitol and 750 ppm sodium fluoride, xylitol and 500 ppm sodium fluoride, and xylitol and triclosan. Twenty 18 to 30 month-old children were selected. Nonstimulated saliva samples were collected and inoculated on brain heart infusion (BHI) agar. Toothpaste dilutions were applied into the agar wells and incubated at 37ºC for 24 hours in microaerophilic conditions. Saline and 0.12% chlorhexidine were used as controls. Antimicrobial activity was determined in duplicate by agar-well diffusion technique. Bacterial growth inhibition zones were recorded in mm. Statistical analysis was performed using ANOVA and Tukey's test (p

Objective: To evaluate the pulp tissue of rat molars after pulpotomies with mineral trioxide aggregate (MTA), Biodentine TM (BDT) and calcium hydroxide (CH) mixed with sterile saline solution (24 hours, 72 hours, 7 days and 15 days), through correlating MPO activity with active neutrophils and MMP8 activity with tissue remodeling . Material and Methods: Thirty-eight Wistar rats were randomly distributed into groups (control, I (MTA gray), II (BDT), and III (CH)) and subdivided according to the study period of 24 hours, 72 hours, 7 days or 15 days after pulpotomy. MMP8 activity was assessed through fluorescence technique, and MPO activity was determined using the MPO assay. Results: A gradual decrease of MPO and MM8 activity occurred in the group MTA over the experimental periods (p

Objetivo: Avaliar a performance mastigatória e o nível e satisfação dos indivíduos parcialmente desdentados, após serem reabilitados com próteses parciais removíveis (PPRs), com ênfase na importância desse tratamento para com a saúde bucal no contexto da odontologia atual onde os implantes dentários osseointegrados tem sido bastante utilizado. Metodologia: 23 pacientes parcialmente desdentados foram reabilitados com PPRs na clínica de prótese dentária da Unifal-MG. Foram executados, antes e depois do tratamento reabilitador, questionários avaliando o nível de satisfação desses pacientes no que diz respeito a estética e função mastigatória, e testes de performance mastigatória (PM) utilizando um material simulador de alimento a partir do silicone de condensação Zetaplus – Zermack. Resultados: Após o tratamento reabilitador, os pacientes relataram sentirem-se mais satisfeitos em relação a estética e função dos dentes. Na análise estatística, O valor-p do teste t encontrado foi de 0,002, levando à rejeição da hipótese nula e conclusão de que o diâmetro geométrico médio () das partículas mastigadas é menor após o tratamento reabilitador com prótese parcial removível. Conclusão: O tratamento com PPR proporciona melhora na PM e no nível de satisfação dos pacientes no que diz respeito a estética e função mastigatória sendo, portanto, de extrema importância para a saúde pública, uma vez que impacta positivamente na melhora da qualidade de vida dos indivíduos.

Resumo Introdução Os cimentos resinosos são extensivamente utilizados na fixação de restaurações indiretas de cerâmica e cerômero, sendo classificados em duas categorias: os cimentos resinosos convencionais, que não apresentam uma adesão inerente à estrutura dental e requerem o uso de um sistema adesivo e os cimentos resinosos autoadesivos, que não requerem um tratamento adesivo prévio do substrato dentário. Objetivo Avaliar a resistência de união de dois cimentos resinosos, convencional e autoadesivo, quando utilizados na cimentação de restaurações cerâmicas e ceroméricas, trazendo elementos para propiciar melhor compreensão da interação adesiva em procedimentos de cimentação com as referidas categorias de cimentos resinosos. Material e método Dentes humanos (n=20), cedidos pelo banco de dentes da Universidade Federal de Alfenas (UNIFAL), foram preparados para que cilindros de cerâmica ou de cerômero fossem cimentados utilizando-se dois tipos de cimentos resinosos (autoadesivo e convencional). Após a cimentação, 20 palitos foram obtidos e submetidos ao teste de tração, avaliando-se a força necessária para a fratura. Os valores obtidos foram submetidos à análise estatística empregando-se a análise de variância (ANOVA) e o teste de Tukey. Resultado As forças mínimas e máximas necessárias ao rompimento do cimento convencional foram superiores às mesmas requeridas para o rompimento da união promovida pelo cimento autoadesivo, bem como as medianas e as médias aritméticas, independentemente do material restaurador empregado. O teste de Tukey demonstrou que as diferenças entre os cimentos empregados são estatisticamente significantes, independentemente do material restaurador. Conclusão Os resultados deste trabalho sugerem que o material utilizado para a confecção dos corpos de prova (cerâmica ou cerômero) não influenciou na resistência à tração, sendo que o cimento convencional apresentou valores superiores de resistência. Abstract Introduction Resin cements are extensively used in the fixation of indirect restorations of ceramics and ceramics, divided into two categories: conventional resin cements, which do not present an inherent adhesion to the dental structure and require the use of an adhesive system, and the self-adhesive resin cements, which do not require a prior adhesive treatment of the dental substrate. Objective: To evaluate the microtensile bond strength of two resin-based cements, conventional and self-adhesive, according to required operating protocols, when luting ceramic and indirect composite restorations. Material and method Human molars (n=20) donated by UNIFAL teeth bank were prepared and, after being divided into two groups, ceramic or composite cylinders were luted to them with two resin-based cements (conventional and self-adhesive). Prepared teeth were sectioned vertically in both buccal-lingual and mesio-distal directions, to obtain 8 mm high, square-shaped “sticks” that were subject to microtensile bond strength test, and the necessary force to fracture them was evaluated. Results were subject to two-way ANOVA and Tukey test. Result Minimum and maximum forces to disrupt conventional cement were greater than the required one for self-adhesive cement, as well as mean bond strength, despíte of the restorative material. Tukey test showed that diferences were statistically significant, regardless the restorative material. Conclusion Restorative materials did not influence microtensile bond strength values, with no statistically significant differences. The difference between microtensile bond strength values of resin cements tested was statistically significant.

Made available in DSpace on 2019-10-06T16:33:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01. Added 1 bitstream(s) on 2019-10-09T18:35:28Z : No. of bitstreams: 1 S1678-77572019000100450.pdf: 538138 bytes, checksum: d2b685a54cc928f8bc8b772b83b4f774 (MD5) Objectives: To evaluate the effect of calcium hydroxide (CH) associated with two different vehicles as a capping material for pulp tissue in primary molars, compared with mineral trioxide aggregate (MTA). Methodology: Forty-five primary mandibular molars with dental caries were treated by conventional pulpotomy using one of the following materials: MTA only (MTA group), CH with saline (CH+saline group) and CH with polyethylene glycol (CH+PEG group) (15 teeth/group). Clinical and periapical radiographic examinations of the pulpotomized teeth were performed 3, 6, and 12 months after treatment. Data were tested by chi-squared analysis and a multiple comparison post-test. Results: The MTA group showed both clinical and radiographic treatment success in 14/14 teeth (100%), at all follow-up appointments. By clinical evaluation, no teeth in the CH+saline and CH+PEG groups had signs of mobility, fistula, swelling or inflammation of the surrounding gingival tissue. However, in the CH+saline group, radiographic analysis detected internal resorption in up to 9/15 teeth (67%), and inter-radicular bone resorption and furcation radiolucency in up to 5/15 teeth (36%), from 3 to 12 months of follow-up. In the CH+PEG group, 2/11 teeth (18%) had internal resorption and 1/11 teeth (9%) presented bone resorption and furcation radiolucency at all follow-up appointments. Conclusion: CH with PEG performed better than CH with saline as capping material for pulpotomy of primary teeth. However, both combinations yielded clinical and radiographic results inferior to those of MTA alone. Universidade Federal de Alfenas (UNIFAL) Faculdade de Odontologia Departamento de Clínica e Cirurgia Universidade Estadual Paulista (UNESP) Faculdade de Odontologia de Araçatuba Departamento de Dentística Restauradora-Endodontia Universidade de São Paulo Faculdade de Odontologia de Bauru Departamento de Odontopediatria Ortodontia e Saúde Coletiva Universidade Estadual Paulista (UNESP) Faculdade de Odontologia de Araçatuba Departamento de Dentística Restauradora-Endodontia

Made available in DSpace on 2018-11-26T16:32:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-03-01. Added 1 bitstream(s) on 2019-10-09T18:25:56Z : No. of bitstreams: 1 S1678-77572016000200114.pdf: 305348 bytes, checksum: 0127cf4b9583e255fb70ce4adc47bbb2 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Because many mechanical variables are present in the oral cavity, the proper load transfer between the prosthesis and the bone is important for treatment planning and for the longevity of the implant-supported fixed partial denture. Objectives: To verify the stress generated on the peri-implant area of cantilevered implant-supported fixed partial dentures and the potential effects of such variable. Material and Methods: A U-shaped polyurethane model simulating the mandibular bone containing two implants (circle divide 3.75 mm) was used. Six groups were formed according to the alloy's framework (CoCr or PdAg) and the point of load application (5 mm, 10 mm and 15 mm of cantilever arm). A 300 N load was applied in pre-determined reference points. The tension generated on the nnesial, lingual, distal and buccal sides of the peri-implant regions was assessed using strain gauges. Results: Two-way ANOVA and Tukey statistical tests were applied showing significant differences (p

Objective: To evaluate the microhardness of specimens of acrylic resins VipiCril® (thermally polymerized resin) and Bosworth New Truliner® (self-polymerized resin), before and after immersion in solutions of 0.12% chlorhexidine digluconate, 1% sodium hypochlorite, Corega Tabs® and water (control), testing the null hypothesis that the mouthwashes and chemicals used to disinfect complete dentures do not interfere with the superficial microhardness, and can therefore be used as adjuncts to oral hygiene of edentulous patients. Methods: Sixty specimens of resin VipiCril®(thermally polymerized resin) and 60 specimens of resin Bosworth New Truliner® (self-polymerized resin) measuring 16 mm of diameter and 6 mm of height were prepared, which were randomly divided into four groups of 15 specimens each, undergoing Knoop hardness tests (KHN) both before and after cycles of immersion in solutions of 0.12% chlorhexidine digluconate, 1% sodium hypochlorite, Corega Tabs® and water (control). Results: The specimens of resins VipiCril and Bosworth immersed in solutions of 0.12% chlorhexidine, Corega Tabs® and water showed decreased microhardness. Conclusion: The 1% sodium hypochlorite solution caused least damage to the denture structure, not leading to decrease of the superficial microhardness. RESUMO Objetivo: Avaliar a microdureza de corpos de prova das resinas acrílicas VipiCril® (resina termopolimerizável) e Bosworth New Truliner®(resina autopolimerizável), antes e após, a imersão em soluções de digluconato de clorexidine a 0,12 %, hipoclorito de sódio a 1%, Corega Tabs® e água (controle), testando a hipótese nula de que os enxaguatórios bucais e substâncias químicas utilizadas na desinfecção de próteses totais não interferem na microdureza superficial, podendo assim, serem utilizados como coadjuvantes na higiene bucal de pacientes desdentados. Métodos: Foram confeccionados 60 corpos de prova da resina VipiCril®(termopolimerizável) e 60 corpos de prova da resina Bosworth New Truliner® (autopolimerizável) com 16mm de diâmetro por 6mm de altura, estes foram divididos randomicamente em quatro grupos de 15 amostras cada, sendo submetidos a testes de microdureza Knoop (KHN), antes e após, ciclos de imersões em soluções de digluconato de clorexidine a 0,12%, hipoclorito de sódio a 1%, Corega Tabs® e água (controle). Resultados: Os corpos de prova de resina VipiCril e Bosworth imersos nas soluções de clorexidine a 0,12%, Corega Tabs®e água apresentaram diminuição de microdureza. Conclusão: A solução de hipoclorito de sódio a 1% causou menor dano à estrutura da prótese não causando diminuição da microdureza superficial.

Objective: This study aimed at evaluating the micro-hardness of an acrylic resin used for provisional crowns. Materials and methods: Five different processing techniques (direct and indirect) were assessed: (I) auto polymerizing resin in sandy stage; (II) auto polymerizing resin in plastic stage; (III) bead-brush technique; (IV) auto polymerizing resin under pressure; (V) heat-cured acrylic resin under pressure. Five specimens were made for each test group. For the initial micro-hardness test, the specimens were immersed in deionized water for 48 hours. For the analysis of the final micro-hardness, the specimens were subjected to pH-cycling to simulate the changes in the pH level which occur in the oral cavity. Results: Tests revealed that the micro-hardness was decreased after the pH-cycling. However, no statistical difference was found among the different types of acrylic resin polymerization techniques. Conclusion: It was concluded that the micro-hardness is not directly related to the polymerization technique for making provisional crowns.

OBJECTIVES: The complexity and heterogeneity of human bone, as well as ethical issues, most always hinder the performance of clinical trials. Thus, in vitro studies become an important source of information for the understanding of biomechanical events on implant-supported prostheses, although study results cannot be considered reliable unless validation studies are conducted. The purpose of this work was to validate an artificial experimental model based on its modulus of elasticity, to simulate the performance of human bone in vivo in biomechanical studies of implant-supported prostheses. MATERIAL AND METHODS: In this study, fast-curing polyurethane (F16 polyurethane, Axson) was used to build 40 specimens that were divided into five groups. The following reagent ratios (part A/part B) were used: Group A (0.5/1.0), Group B (0.8/1.0), Group C (1.0/1.0), Group D (1.2/1.0), and Group E (1.5/1.0). A universal testing machine (Kratos model K - 2000 MP) was used to measure modulus of elasticity values by compression. RESULTS: Mean modulus of elasticity values were: Group A - 389.72 MPa, Group B - 529.19 MPa, Group C - 571.11 MPa, Group D - 470.35 MPa, Group E - 437.36 MPa. CONCLUSION: The best mechanical characteristics and modulus of elasticity value comparable to that of human trabecular bone were obtained when A/B ratio was 1:1.

Cyanocrylates have been widely used in the medical and dental fields for several years. In Dentistry, cyanoacrylates have been used for suturing, pulp capping, as retrofilling material in endodontic surgeries, and as cervical plug for pulpless teeth bleaching. The biocompatibility of these adhesives has been the topic of many researches and subcutaneous implantation is an effective methodology for these studies. The present study evaluated the biocompatibility of three different cyanoacrylate-based adhesives. Thirty-six Wistar rats were used, divided into four groups of 9 animals each: A (control) - distilled water, B - cyanoacrylate ester (Super Bonder), C - n-butyl-cyanoacrylate (Histoacryl) and D - alpha-cyanoacrylate (Three Bond). The materials were dispensed in sponges of polyvinyl chloride, the animals were incised and the sponges were inserted in the subcutaneous tissue and sutured. Each group was sub-divided according to the time of sacrifice of the animals: 7, 21 and 45 days. Subjective analysis of the histologic material showed that all groups presented some degree of irritability, but the inflammatory reaction decreased with the experimental time in all groups. Group D showed an inflammatory reaction which was closer to that of the control group and was considered to have good biocompatibility. Groups B and C were similar and presented more aggressive inflammatory reactions when compared to the control group. Based on the results, it was concluded that alpha-cyanoacrylate (Three Bond) was the most biocompatible adhesive because it caused the lowest levels of inflammation.

Passive fit has been considered an important requirement for the longevity of implant-supported prostheses. Among the different steps of prostheses construction, casting is a feature that can influence the precision of fit and consequently the uniformity of possible deformation among abutments upon the framework connection.This study aimed at evaluating the deformation of abutments after the connection of frameworks either cast in one piece or after soldering.A master model was used to simulate a human mandible with 5 implants. Ten frameworks were fabricated on cast models and divided into 2 groups. Strain gauges were attached to the mesial and distal sides of the abutments to capture their deformation after the framework's screw retentions were tightened to the abutments.The mean values of deformation were submitted to a 3-way analysis of variance that revealed significant differences between procedures and the abutment side. The results showed that none of the frameworks presented a complete passive fit.The soldering procedure led to a better although uneven distribution of compression strains on the abutments.

Nonpassive fit frameworks are believed to lead to implant overload and consequently loss of osseointegration. This is one of the most commonly reported failures of implant prostheses. In an ideal situation of passive fit, when torque is applied to bring the abutment-cylinder interface together some amount of deformation can be expected, and it should be homogeneous along the periphery of the abutment. The aim of this study was to verify the amount of abutment deformation that can be expected when a free-standing cylinder is screwed into place. This could give insight into what should be accepted as passive fit.Strain gauges were bonded to the sides of five standard abutments that had machined palladium-silver cylinders or cobalt-chromium cast cylinders screwed into place. Measurements were taken to verify the deformation at each site.Values of abutment deformation after abutment screw tightening ranged from -127.70 to -590.27 microepsilon. The deformation recorded for palladium-silver prosthetic cylinder tightening ranged from 56.905 to -381.50 microepsilon (mean: 173.298 microepsilon) and from -5.62638 to -383.86 microepsilon (mean: 200.474 microepsilon) for cobalt-chromium cylinders. There was no statistically significant difference among the two groups.Both abutment screw tightening and prosthetic cylinder screw tightening result in abutment deformation, which is compressive most of the time.

O sucesso a longo prazo dos implantes tem como fatores críticos a incidência e a transferência de estresses mecânicos sobre a prótese, intermediários, implantes e destes para o tecido ósseo adjacente, devendo cada parte deste sistema ser submetido somente a forças às quais estão aptos a receber. A proposta deste trabalho foi avaliar a deformação gerada nos intermediários e na região óssea peri-implantar diante da aplicação de cargas funcionais e parafuncionais em prótese parcial fixa de três elementos parafusadas sobre dois implantes. Para este trabalho, foi utilizado um modelo experimental homogêneo à base de poliuretano, simulando o tecido ósseo, com dois implantes do tipo hexágono externo paralelos que receberam intermediários do tipo multi-unit. Na superfície de cada intermediário foram instalados três sensores (strain gauges), capazes de medir a microdeformação dispostos de maneira eqüidistante entre si. Na região óssea simulada, foram instalados quatro sensores para cada implante, posicionados nas faces mesial, distal, vestibular e lingual. A aplicação da carga estática de 300N foi realizada em uma máquina de ensaios universais. As leituras foram realizadas em quatorze momentos para todos os corpos de prova, variando o direcionamento da carga (axial e inclinada à 30 graus) e simulando ainda sete diferentes pontos de aplicação de carga (1- pilar mesial, 2 - pôntico, 3- pilar distal, 4- simultaneamente no pilar mesial, pontico e pilar distal, 5- no pilar mesial e distal, sem contato no pôntico, 6- no pilar mesial e no pôntico, 7- no pilar distal e no pôntico). Os resultados mostraram que a direção da carga interferiu na magnitude e distribuição da microdeformação, de forma que, no osso simulado, os valores encontrados na carga axial se encontraram dentro da tolerância fisiológica independente do local de aplicação de carga. Observou-se uma distribuição mais uniforme quando a carga foi aplicada simultaneamente nos pilres mesial, pôntico e pilar distal. Por outro lado, valores de microdeformação acima do limite de tolerância foram observados para a carga inclinada e nesta situação o local de aplicação teve influência na microdeformação, com valores extremamente elevados e sem uniformidade na distribuição, devendo o carregamento oblíquo ser evitado. Long-term success with implants has some critical factors such as incidence and transmission of mechanical stress to the prosthesis, abutments, and implants to the adjacent bone tissue. Each part of the system should be subjected to loads under its strength limit. The purpose of the present study was to evaluate abutment and peri-implant bone tissue strains during functional and parafunctional loads application in a three-unit screw-retained fixed prosthesis supported by two implants. In order to simulate the bone tissue, an experimental model made of homogeneous polyurethane was used wherein two external hexagon implants were placed parallel to each other, provided with multi-unit abutments. On the surface of each abutment three sensors (strain gauges) were positioned equidistant to each other to measure microstrains. The simulated bone around each implant received four strain gauges, positioned on the mesial, distal, buccal and lingual aspects. The tests were performed applying a 300N static load on a universal testing machine. The readings were made at fourteen moments for each specimen, changing load direction (axial and 30 degrees oblique) and also simulating seven different points of load application (1- mesial abutment, 2- pontic, 3- distal abutment, 4- simultaneously on the mesial abutment, pontic and distal abutment, 5- mesial and distal abutment (no pontic contact), 6- mesial abumtent and pontic, 7- distal abutment and pontic. The results showed that the load direction significantly influenced the magnitude and distribution of microstrains, so that for the simulated bone, the values found during axial load were within the physiological threshold independent of the point of load application; however, a more uniform distribution was observed when force was applied simultaneously on the mesial abutment, pontic and distal abutment. Furthermore, microstrain values above the tolerance limits were observed during oblique load, and for this condition, the point of load application significantly influenced the microstrains, with extremely high values and non-uniform distribution for all load conditions tested. Therefore, oblique loading must be avoided.