Desgaste e rugosidade superficial de cimentos de ionômero de vidro utilizados como selantes, após escovação simulada

O presente estudo foi conduzido in vitro com o intuito de constatar as propriedades (desgaste e rugosidade) dos CIV, as quais influenciam na sua indicação como material selador de fossas e fissuras. Os materiais empregados foram Fuji Plus, Ketac-Molar e Vitremer (duas proporções: 1:1 e ¼:1). O selante Delton foi controle. A determinação do desgaste foi obtida através da quantidade de massa perdida após a escovação e a rugosidade através da análise quantitativa da superfície. Os resultados mostraram que o Vitremer diluído e o Fuji Plus apresentaram maior grau de desgaste e maior aumento de rugosidade. Apesar de clinicamente se encontrar um maior uso dos ionômeros de vidro cimentantes ou diluídos como forma alternativa para material selador; este trabalho permitiu concluir que estes possuem propriedades bastante inferiores quando comparados aos ionômeros restauradores que, por sua vez, possuem resultados semelhantes ao selante resinoso.The purpose of this study was to evaluate, in vitro, the properties (wear and roughness) of glass ionomer cements that could influence their indication as pit and fissure sealants. The utilized materials were Fuji Plus, Ketac-Molar and Vitremer (in two different proportions: 1:1 and ¼:1). The resin-based sealant Delton was used as control. By means of an electronic balance (precision of 10-4 g), wear was measured in function of weight loss after simulated toothbrushing. Superficial roughness was determined by means of a surface roughness-measuring apparatus. The results revealed that diluted Vitremer and Fuji Plus were less resistant to toothbrushing abrasion and had the greatest increase in superficial roughness.Although in clinical situations luting or diluted ionomer cements are often utilized as alternatives to resin-based sealants, the resultsof this study revealed that the properties of those cements are worse than those of restorative ionomers, whichpresented results similar to those of the evaluated resin sealant

Efeito da profilaxia profissional com jato de bicarbonato de sódio sobre a microbiota cariogênica

The effect of professional dental prophylaxis with sodium bicarbonate jet on salivary counting of mutans streptococci and lactobacilli in 32 children ranging from 7 to 10 years of age, has been assessed. Whole stimulated saliva was collected before the prophylaxis, immediately after it and 30 days later, and the number of CFU/ml in the saliva was detected through the Caritest system. A statistically significant immediate decrease on salivary levels of both microorganisms was observed, 50% for mutans streptococci and 27% for lactobacilli. For mutans streptococci this decrease continued through the 30 days period; the same did not occur with lactobacilli, that returned to their baseline values.Avaliou-se o efeito da profilaxia dentária profissional com o jato de bicarbonato de sódio na contagem salivar de estreptococos do grupo mutans e de lactobacilos em 32 crianças entre 7-10 anos. Coletou-se saliva total estimulada antes e 60 minutos após o procedimento, e decorridos 30 dias, sendo o número de UFC/mL saliva detectado através do sistema Caritest. Constatou-se uma redução imediata, estatisticamente significativa, nos níveis salivares de ambos os microrganismos, sendo de 50% para estreptococos do grupo mutans e de 27% para lactobacilos. Para os estreptococos do grupo mutans, esta redução persistiu pelo período de 30 dias, o mesmo não ocorrendo para os lactobacilos, que retornaram aos seus valores iniciais

Efeito de diferentes métodos de profilaxia sobre o esmalte hígido e desmineralizado

Considering the importance of professional plaque control for caries prevention, this study comprised an in vitro evaluation of wear by two prophylaxis methods (sodium bicarbonate jet - Profident and pumice and brush) on sound bovine enamel and with artificial carious lesions. Sixty enamel fragments were employed (4x4mm), which were divided into 4 groups: GI - 15 sound blocks treated with pumice and brush; GII - 15 sound blocks treated with Profident; GIII - 15 demineralized blocks treated with pumice and brush, and GIV - 15 demineralized blocks treated with Profident. In the fragments of Groups III and IV, artificial carious lesions were simulated by immersion in 0.05M acetic acid solution 50% saturated with bovine enamel powder at 37ºC for 16h. The specimens were submitted to the prophylactic treatments for 10 seconds. Wear analysis was performed by profilometer and revealed the following results: 0.91µm - GI; 0.42µm - GII; 1.6µm - GIII, and 0.94µm - GIV. The two-way ANOVA and Tukey's test (pTendo em vista a importância do controle profissional da placa na prevenção da cárie, este estudo avaliou in vitro o desgaste de dois métodos de profilaxia (jato de bicarbonato de sódio-Profident e escova de Robinson com pasta de pedra pomes) sobre o esmalte bovino hígido e com lesões artificiais de cárie. Foram utilizados 60 fragmentos de esmalte (4 X 4mm), divididos em 4 grupos: GI- 15 blocos hígidos tratados com escova de Robinson e pasta de pedra pomes; GII- 15 blocos hígidos tratados com Profident; GIII- 15 blocos desmineralizados tratados com escova de Robinson e pedra pomes e GIV- 15 blocos desmineralizados tratados com Profident. Nos fragmentos dos grupos III e IV foram simuladas lesões artificiais de cárie através da imersão em solução de ácido acético 0,05M, 50% saturada com pó de esmalte bovino, a 37ºC por 16 h. Os espécimes foram submetidos aos tratamentos profiláticos durante 10 segundos. A análise do desgaste foi feita por meio de perfilometria, encontrando-se os seguintes resultados: 0,91µm-GI; 0,42µm-GII; 1,6µm-GIII e 0,94µm-GIV. Através do teste ANOVA a dois critérios e do teste de Tukey (

Virtual Reality simulator for dental anesthesia training in the inferior alveolar nerve block

Objectives This study shows the development and validation of a dental anesthesia-training simulator, specifically for the inferior alveolar nerve block (IANB). The system developed provides the tactile sensation of inserting a real needle in a human patient, using Virtual Reality (VR) techniques and a haptic device that can provide a perceived force feedback in the needle insertion task during the anesthesia procedure. Material and Methods To simulate a realistic anesthesia procedure, a Carpule syringe was coupled to a haptic device. The Volere method was used to elicit requirements from users in the Dentistry area; Repeated Measures Two-Way ANOVA (Analysis of Variance), Tukey post-hoc test and averages for the results’ analysis. A questionnaire-based subjective evaluation method was applied to collect information about the simulator, and 26 people participated in the experiments (12 beginners, 12 at intermediate level, and 2 experts). The questionnaire included profile, preferences (number of viewpoints, texture of the objects, and haptic device handler), as well as visual (appearance, scale, and position of objects) and haptic aspects (motion space, tactile sensation, and motion reproduction). Results The visual aspect was considered appropriate and the haptic feedback must be improved, which the users can do by calibrating the virtual tissues’ resistance. The evaluation of visual aspects was influenced by the participants’ experience, according to ANOVA test (F=15.6, p=0.0002, with

Exploring online oral health misinformation: a content analysis

Abstract Considering the unfavorable implications of health falsehoods and the lack of dental research into information disorder, this study aimed to identify and characterize online oral health misinformation. A total of 410 websites published in English were retrieved using Google Advanced Search and screened by two independent investigators to compile falsehoods through thematic content analysis. Afterward, 318 pieces of misinformation were consensually divided into four groups concerning their informational interest (G1), financial, psychological, and social interests produced/disseminated by non-dental professionals (G2) or by dental professionals (G3), and political interests (G4). Social media (Facebook and Instagram) and fact-checking tool (Snopes) were also screened to determine the spread of falsehoods by identifying corresponding posts and warnings. As a result, misinformation was mainly associated with gum diseases (12.0%), root canal treatment (11.6%), toothache (10.4%), fluoride (10.4%), and dental caries (9.8%), with a special highlight on recommendations for the usage of natural products, toxicity concerns, and anti-fluoridation propaganda. Additionally, most misinformation was allocated in G3 (41.9%), which presented a statistically higher frequency of financial interests than G4. Finally, falsehoods were considerably identified on Facebook (62.9%) and Instagram (49.4%), especially G3 and G4. Nevertheless, Snopes has debunked only 5.9% of these content items. Therefore, misinformation was predominantly produced or disseminated by dental professionals mainly motivated by financial interests and usually linked to alternative/natural treatments. Although these items were shared on social media, fact-checking agencies seemed to have limited knowledge about their dissemination

Oral antibacterial effect of chlorhexidine treatments and professional prophylaxis in children

Aim: The primary aim of this longitudinal study was to evaluate additional effects of 4-week chlorhexidine digluconate (CHX) gel treatments to control Aggregatibacter actinomycetemcomitans counts in children after professional dental prophylaxis. Porphyromonas gingivalis and Streptococcus mutans counts were also determined to evaluate the secondary effects of anti-plaque treatments on microbial shifts. Methods: Twenty-six children with A. actinomycetemcomitans counts >4 log10/ mL of saliva and/or Quigley-Hein plaque index >3.0 were enrolled in this study. Patients were randomly assigned to groups GI (placebo gel), GII (0.5% CHX gel), GIII (1% CHX gel), and GIV (2% CHX gel). Four sessions of treatment were performed during 4 weeks after a session of professional dental prophylaxis. Real-Time polymerase chain reaction (PCR) was used to determine viable microorganism counts in non-stimulated whole saliva samples collected at baseline, one week, one month and three months after interruption of treatments. Results: A reduction of all bacterial counts was detected after the 3-month follow-up in all groups. Lower counts of P. gingivalis were achieved from 1 week on after treatments. The 2% CHX concentration seemed to contribute to lower A. actinomycetemcomitans levels and increase S. mutans levels. Conclusions: Professional dental prophylaxis was effective to control salivary levels of A. actinomycetemcomitans, P. gingivalis and S. mutans. Additional antimicrobial effects, however, were not observed by the combination of professional dental prophylaxis and 4-week chlorhexidine gel treatments

Transcrição reversa e reação em cadeia da polimerase: princípios e aplicações em odontologia

Various molecular biology techniques have become available in the last few years. One of the most revolutionary of these techniques regarding nucleic acid analysis is the polymerase chain reaction (PCR), which was first described in 1985. This method relies on the exponential amplification of specific DNA fragments, resulting in millions of copies that can serve as templates for different kinds of analyses. PCR can be preceded by a reverse transcription (RT) reaction in order to produce cDNA from RNA (RT-PCR). RT-PCR provides the possibility to assess gene transcription in cells or tissues. PCR and RT-PCR techniques have been instrumental in dental research, and show potential to be used for diagnosis as well as for treatment and prevention of many diseases (dental caries, periodontal disease, endodontic infections and oral cancer). Compared to other traditional methodologies, PCR and RT-PCR show many advantages including high specificity, sensitivity, and speed. Since PCR and RT-PCR are relatively new techniques and are not available to most students and professionals involved with dentistry, the aim of this work is to present the details of these techniques as well as dental literature reports in which they were used.Várias técnicas de biologia molecular têm sido disponibilizadas nos últimos anos. Uma que revolucionou a análise de ácidos nucléicos foi a reação em cadeia da polimerase (PCR), descrita pela primeira vez em 1985. Esta técnica baseia-se na possibilidade de amplificação exponencial de fragmentos específicos de DNA, com a criação de milhões de cópias que servirão como matéria-prima para diferentes tipos de análises. A PCR pode ser precedida por uma reação de transcrição reversa (RT) para a obtenção de cDNA a partir de RNA (RT-PCR), representando, por exemplo, uma possibilidade de análise de expressão gênica em células ou tecidos. As técnicas de PCR e RT-PCR têm sido utilizadas em pesquisas odontológicas como ferramentas auxiliares para nortear não só o diagnóstico como também o tratamento e prevenção de várias doenças (cárie, doença periodontal, lesões endodônticas e câncer), uma vez que se mostram vantajosas em comparação a outras técnicas tradicionais pela sua alta especificidade, alta sensibilidade e rapidez. Por se tratar de técnicas relativamente novas e não disponíveis para a maioria dos profissionais e estudantes de Odontologia, o objetivo do presente trabalho é apresentar detalhes da PCR e da RT-PCR, bem como trabalhos da literatura em que ambas foram utilizadas

Perfil de tratamento de urgência de crianças de 0 a 15 anos atendidas no serviço de urgência odontológica da Faculdade de Odontologia de Bauru, Universidade de São Paulo

Dental recordings of 0 to 15-year-old patients assisted at Urgency Dental Service (UDS) from Bauru Dental School, University of São Paulo, in 2001 and 2002, were assessed in order to quantify the number of patients that used the service, to determine attendance patterns, and to record the frequency of different types of dental emergencies and their performed treatment. Data were plotted and submitted to a descriptive statistical analysis. Among the total of patients attended at UDS (6020), 1166 (19.37%) were children, with mean age of 9.24 years. Trauma was the cause for 199 (17.06%) of the recorded urgency visits. It occurred more frequently in children between 0 and 3 years of age (34.42%), and between 7 and 12 years of age (18.12%). The main treatments performed were temporary restoration (33.33%) for coronal fracture, and orientation (24.44%) for luxation. Nontraumatic events were the etiology for 967 (82.92%) of the total urgency diagnosis. The most commonly found nontraumatic diagnosis was dental caries lesions (61.75%), followed by problems of eruption or root resorption (14.27%) and bone or soft tissue lesions (6.51%), among others (17.47%). The most frequent treatments performed for caries lesions were: excavation and temporary restoration (39.39%) when there was no abscess, and coronal opening and dressing (40.95%) for caries lesions with abscess. There was an increasing trend in caries lesions prevalence according to the rising of the age, in contrast to trauma prevalence. Treatment for both situations was done according to the indicated protocol for each case.Prontuários odontológicos de crianças de 0 a 15 anos de idade atendidas no Setor de Urgência Odontológica (SUO) da Faculdade de Odontologia de Bauru, Universidade de São Paulo, em 2001 e 2002, foram avaliados a fim de se quantificar o número de pacientes que utilizaram o serviço, determinar os padrões de atendimento e relatar a freqüência de diferentes tipos de emergências odontológicas e dos tratamentos realizados. Os dados foram tabulados e submetidos a uma análise estatística descritiva. Do total de pacientes atendidos no SUO (6020), 1166 (19,37%) eram crianças, com média de idade de 9,24 anos. Lesões traumáticas foram responsáveis por 199 (17,06%) do total de visitas de emergência. Isso ocorreu mais freqüentemente em crianças entre 0 e 3 anos (34,42%), e entre 7 e 12 anos (18,12%). Os principais tratamentos realizados foram restauração temporária (33,33%) para fratura coronária, e orientação (24,44%) para luxação. Eventos não-traumáticos foram responsáveis por 967 (82,92%) do total de diagnósticos de emergência. O diagnóstico mais comumente encontrado foi cárie dentária (61,75%), seguida por problemas de irrupção e reabsorção óssea (14,27%) e lesões em tecido duro ou mole (6,51%), entre outros (17,47%). Os tratamentos realizados com maior freqüência para os casos de cárie foram: escavação e restauração temporária (39,39%) quando não havia abscesso, e abertura coronária e curativo (40,95%) para cáries com abscesso. Houve uma tendência para o aumento na prevalência de cárie com a idade. O oposto foi observado para traumatismo dentário. O tratamento para ambos estava de acordo com o preconizado para este tipo de serviço

Evaluation of marginal microleakage and depth of penetration of glass ionomer cements used as occlusal sealants

OBJETIVE: the aim of this study was to conduct an in vitro comparison of marginal microleakage (MM) and the depth of penetration (DP) of glass ionomer cements (GIC) and a resin sealant (RS) into occlusal pit and fissures. METHODS: for that purpose, 60 intact third molars were equally distributed to 5 groups: G1 - 37% phosphoric acid / Delton; G2 - 40% polyacrylic acid / Ketac-Molar / nail varnish; G3 - Fuji Plus conditioner / Fuji Plus/ nail varnish; G4 -37% phosphoric acid / Vitremer / Finishing gloss; G5 -37% phosphoric acid / Vitremer prepared with a 1:4 ratio of powder / Finishing gloss. The teeth were submitted to a thermal treatment corresponding to 300 cycles (15 sec, 5/55(0)C), followed by complete coating with nail varnish, except for 1mm beyond the contour of the sealant. Afterwards, the teeth were immersed in 0.5% basic fuchsine for 24 hours. Thereafter, the teeth were sectioned in buccolingual direction and microscopically analyzed (150x magnification) by means of predetermined scores. The results were subject to the Kruskal-Wallis test. RESULTS: there was no statistical difference between the materials tested in relation to the DP, being that all groups displayed nearly complete filling of the fissures. No sealant material was able to prevent dye penetration; however, the GICs provided better results of MM, with significant difference when compared to the RS. CONCLUSION: all materials investigated presented a satisfactory degree of penetration into the fissures; however, the glass ionomer cements displayed better performance in the marginal microleakage test compared to the resin sealant.OBJETIVO: o objetivo deste estudo foi comparar in vitro a microinfiltração marginal (MM) e o grau de profundidade de penetração (DP) de cimentos de ionômero de vidro (CIV) e um selante resinoso (SR) em fossas e fissuras oclusais. MATERIAIS E MÉTODOS: para tanto, 60 terceiros molares hígidos foram igualmente distribuídos em 5 grupos: G1- ácido fosfórico 37%/Delton; G2- ácido poliacrílico 40%/Ketac-Molar/esmalte cosmético; G3- Fuji Plus conditioner/Fuji Plus/ esmalte de cosmético; G4 - ácido fosfórico 37%/Vitremer/Finishing gloss; G5- ácido fosfórico 37%/Vitremer diluído na proporção de 1/4 de pó/Finishing gloss. Os dentes foram submetidos a um tratamento térmico correspondente a 300 ciclos (15 seg, 5/ 55(0)C), seguindo da total cobertura com esmalte cosmético, exceto 1mm além do contorno do material selador, sendo então imersos em solução de fucsina básica 0,5%, por 24 horas. Posteriormente, os dentes foram seccionados vestíbulo-lingualmente, e avaliados microscopicamente (aumento 150X), por meio de escores pré-determinados. Os resultados foram submetidos ao Teste de Kruskal Wallis. RESULTADOS: não houve diferença estatística entre os materiais testados em relação à DP, sendo que todos os grupos apresentaram um preenchimento quase total das fissuras. Nenhum material selador foi apto em impedir a penetração da solução corante, entretanto, os CIVs promoveram os melhores resultados de MM, distinguindo-se significantemente em relação ao SR. CONCLUSÃO: Todos os materiais testados apresentaram um grau de penetração satisfatório no interior das fissuras, no entanto, os cimentos de ionômero de vidro demonstraram melhor comportamento no teste de microinfiltração marginal, quando comparado ao selante resinoso

Fluoride release profile of a nanofilled resin-modified glass ionomer cement

The present study aimed to compare the fluoride (F-) release pattern of a nanofilled resin-modified glass ionomer cement (GIC) (Ketac N100 - KN) with available GICs used in dental practice (resin-modified GIC - Vitremer - V; conventional GIC - Ketac Molar - KM) and a nanofilled resin composite (Filtek Supreme - RC). Discs of each material (n=6) were placed into 4 mL of deionized water in sealed polyethylene vials and shaken, for 15 days. F- release (μg F-/cm²) was measured each day using a fluoride-ion specific electrode. Cumulative F- release means were statistically analyzed by linear regression analysis. In order to analyze the differences among materials and the influence of time in the daily F- release, 2-way ANOVA test was performed (α=0.05). The linear fits between the cumulative F- release profiles of RC and KM and time were weak. KN and V presented a strong relationship between cumulative F- release and time. There were significant differences between the daily F- release overtime up to the third day only for GICs materials. The daily F- release means for RC were similar overtime. The results indicate that the F- release profile of the nanofilled resin-modified GIC is comparable to the resin-modified GIC.O presente estudo teve como objetivo comparar o padrão de liberação de fluoreto (F-) de um cimento de ionômero de vidro (CIV) nanoparticulado modificado por resina (Ketac N100 - KN) com CIVs disponíveis na prática clínica (CIV modificado por resina - Vitremer - V; CIV convencional - Ketac Molar - KM) e uma resina composta nanoparticulada (Filtek Supreme - RC). Discos de cada material (n=6) foram imersos em 4 mL de água deionizada em frascos de polietileno e agitados durante 15 dias. A liberação de F- (μg F-/cm²) foi medida a cada dia utilizando um eletrodo de F- específico. Os valores de liberação cumulativa de F- foram analisados estatisticamente por análise de regressão linear. Com o objetivo de analisar as diferenças entre os materiais e a influência do tempo na liberação diária de F- foi aplicado o teste ANOVA a dois critérios (α=0,05). A relação entre os padrões de liberação de cumulativo de F- da RC e KM e o tempo foram fracas. Os materiais KN e V apresentaram uma relação forte entre a liberação cumulativa de F- e o tempo. Diferenças significativas foram observadas entre a liberação diária de F- até o terceiro dia somente para os cimentos ionoméricos. Os resultados indicam que o padrão de liberação de F- do CIV modificado por resina nanoparticulado é semelhante ao CIV modificado por resina