Color change, tooth sensitivity, aesthetic self-perceptions and quality of life after at-home dental bleaching / Mudança de cor, sensibilidade dental, autopercepção estética e qualidade de vida após clareamento dental caseiro

Objective: The aim of this study was to determine the color change, tooth sensitivity, aesthetic self-perception and quality of life after at-home dental bleaching. Material and Methods: Dental examination was performed and the initial color of the upper right incisor was recorded using a spectrophotometer (Easyshade Compact, Vita Zahnfabrik) and CIELab parameters. Individual vinyl trays were delivered to the patients (n=37) who were instructed to use the carbamide peroxide 16% (Total Blanc Home C16%, DFL) for 2 hours daily for 2 weeks. One-week after the end of treatment, measurements were repeated to calculate color (ΔEab,ΔE00) and whiteness index (ΔWID) variations. Oral Health Impact Profile (OHIP) and Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) questionnaires were applied before and 30 days after treatment. Tooth sensitivity was by checked by visual analogue scale (VAS). Spearnan's correlation tests were used to verify the possible relation between color change parameters and sensitivity. The Wilcoxon test was applied for results obtained by OHIP and PIDAQ questionnaires. Results: Significant color change was observed after 14 days, regardless of the considered parameter. There was no significant correlation between sensitivity and color change. The dental self-confidence domain increased after bleaching (p = 0.029) and the psychological impact decreased (p = 0.001). Conclusion:At-home dental bleaching was effective on the overall whitening and the color change was not related to tooth sensitivity. The bleaching treatment had a positive impact on the quality of life, reducing psychological discomfort and improving dental self-confidence and aesthetic self-perception. (AU)

Objetivo: O objetivo deste estudo foi determinar a mudança de cor, sensibilidade dental, autopercepção estética e qualidade de vida após clareamento dental caseiro. Material e Métodos: Uma consulta inicial foi realizada e a cor inicial do incisivo superior direito foi registrada usando um espectrofotômetro (Easyshade Compact, Vita Zahnfabrik) e parâmetros CIELab. Moldeiras individuais confeccionadas em vinil foram entregues aos pacientes participantes (n = 37), que foram instruídos a usar o gel à base de peróxido de carbamida 16% (Total Blanc Home C16%, DFL) durante 2 horas diárias durante 2 semanas. Uma semana após o término do tratamento, as medidas foram repetidas para calcular a variação de cor (ΔEab, ΔE00) e o índice de brancura (ΔWID). Os questionários OHIP (Oral Health Impact Profile) e PIDAQ (Psychosocial Impact of Dental Aesthetics Questionnaire) foram aplicados antes e 30 dias após o tratamento. A sensibilidade dental foi verificada por meio da escala visual análoga (VAS). Os testes de correlação de Spearnan foram utilizados para verificar a possível relação entre os parâmetros de mudança de cor e sensibilidade. O teste Wilcoxon foi aplicado para os resultados obtidos pelos questionários OHIP e PIDAQ. Resultados: Mudança de cor significativa foi observada após 14 dias, independentemente do parâmetro considerado. Não houve correlação significativa entre a sensibilidade e a mudança de cor. O domínio da autoconfiança dental aumentou após o branqueamento (p = 0,029) e o impacto psicológico diminuiu (p = 0,001). Conclusão: O clareamento dental caseiro foi eficaz no branqueamento geral e a mudança de cor não estava relacionada à sensibilidade dental. O tratamento clareador teve um impacto positivo na qualidade de vida, reduzindo o desconforto psicológico e melhorando a autoconfiança dental e a autopercepção estética.(AU)

Conhecimento de cirurgiões-dentistas sobre a relação entre disfunção temporomandibular e fatores oclusais / Dentists' knowledge about the relationship between temporomandibular dysfunction and oclusal factors

Resumo Introdução As evidências científicas atuais têm demonstrado que o tratamento para disfunção temporomandibular deve seguir uma abordagem conservadora e adaptada ao estado psicossocial do paciente. Entretanto, tratamentos visando às alterações oclusais foram utilizados durante anos pelos cirurgiões-dentistas e o abandono destes paradigmas é essencial para o desenvolvimento da Odontologia. Objetivo Objetivou-se avaliar o conhecimento de cirurgiões-dentistas (CD) sobre a relação entre disfunção temporomandibular (DTM) e fatores oclusais. Material e método Foi enviado, por e-mail, um questionário previamente publicado para os CD registrados no Conselho Regional de Odontologia do Piauí, Brasil (n = 2.500) com dados sobre o profissional, sua formação e seu conhecimento sobre DTM e fatores oclusais. O consenso da literatura atual, "padrão-ouro", foi comparado com as respostas obtidas. Os dados foram analisados descritivamente e através dos testes qui-quadrado e odds ratio (p<0,05). Resultado Quinhentos e cinco CD responderam e 434 compuseram a amostra. A maioria dos participantes era mulher (72,3%), com 7,2 (±6,63) anos de formados, e trabalhava no setor público-privado (39,0%). Os CD foram divididos em dois grupos: GEsp.: especialistas em DTM, Prótese Dentária e/ou Ortodontia (n=234) e GClín.: clínicos gerais e demais especialistas (n=200). GEsp. e GClín. apresentaram respostas similares para a metade das perguntas. Quatro (de seis) perguntas foram respondidas em desacordo com o padrão-ouro: fatores oclusais, interferências em lado de não trabalho, terapia ortodôntica e ajuste oclusal mostraram ser assuntos pouco conhecidos. GEsp. apresentou maior conhecimento com diferença significativa em relação a GClín. acerca da DTM e das interferências oclusais [odds ratio = 2,341 (1,305-4,202), p=0,004]. Conclusão Pode-se concluir que os CD da amostra estudada apresentaram deficiências acerca do conhecimento da relação entre DTM e fatores oclusais. Especialistas em DTM, Prótese Dentária e/ou Ortodontia não demonstraram um maior nível de conhecimento quando comparados aos demais.

Abstract Introduction Current scientific evidence has shown that treatment for temporomandibular disorder should follow a conservative approach that is adapted to the patient's psychosocial status. However, treatments aiming at occlusal changes have been used for years by dentists and the abandonment of these paradigms is essential for the development of dentistry. Objective The aim of this study was to evaluate the knowledge of dentists on the relationship between temporomandibular disorder (TMD) and occlusal factors. Material and method A previously published questionnaire was sent to the dentists registered at the Regional Council of Dentistry of Piauí, Brazil (n = 2,500) with data about the professional, their training and knowledge about TMD and occlusal factors. The consensus of the current literature, "gold standard", was compared with the answers obtained. The data were analyzed descriptively and through chi-square test and odds ratio (p <0.05). Result Five hundred and five dentists answered and 434 composed the sample. The majority of the participants was women (72.3%) with 7.2 (± 6.63) years of education and worked in the public-private sector (39.0%). The dentists were divided into Group 1 (GEsp.): specialists in TMD, dental prosthesis and/or orthodontics (n = 234) and Group 2 (GClin.): clinicians and other specialists (n = 200). GEsp. and GClin. presented similar responses for half of the questions. Four (of six) were answered in disagreement with the gold standard: occlusal factors, interference in the balance, orthodontic therapy and occlusal adjustment were little known. GEsp. presented greater knowledge with a significant difference in relation to GClin. regarding TMD and occlusal interferences (odds ratio = 2,341 (1,305-4,202), p = 0.004). Conclusion It can be concluded that the dentists presented deficiencies in the knowledge of the relationship between TMD and occlusal factors. Dentists specialists in TMD, dental prosthesis and/or orthodontics did not demonstrate a higher level of knowledge when compared to the others.

Baixo nível de ansiedade dos pacientes atendidos no curso de odontologia de uma instituição de ensino superior / Low level of anxiety of patients treated in a dentistry course of a higher education institution

Apesar de benéfico, o tratamento odontológico pode gerar ansiedade para o paciente e para o cirurgião-dentista. Se verificada além de um limite aceitável, a ansiedade pode impedir que o paciente se submeta ao tratamento, comprometendo sua qualidade de vida. Diante da relevância do assunto, objetivou-se avaliar o perfil dos pa¬cientes atendidos nas clínicas odontológicas de uma instituição de ensino e seu nível de ansiedade diante do tratamento odontológico. Foram entrevistados 133 pacientes em tratamento nas clínicas integradas e do mestrado da Universidade Veiga de Almeida, entre março e outubro de 2015. Os pacientes responderam a um questionário com dados socioeconômicos e questões específicas para a identificação do grau de ansiedade ao tratamento odontológico, utilizando a escala DAS (Dental Anxiety Scale). A amostra foi composta de maneira equivalente por homens e mulheres, a maioria tinha mais que 45 anos (51,1%), com renda de até 5 salários mínimos (66,9%) e com grau de instrução superior (56,4%). Embora 88,7% tenham relatado algum nível de an¬siedade, este foi considerado baixo. Não houve diferença estatística entre o grau de ansiedade de homens e mul¬heres (p=0,458). Não se observou associação entre idade, gênero, renda, grau de instrução, frequência de ida ao dentista e o nível de ansiedade (p>0,05). Houve uma associação significativa (p=0,015) entre procedimentos que incomodam durante a consulta, como a alta rotação e a anestesia, e os níveis de ansiedade observados. Pode-se concluir que o nível de ansiedade dos pacientes atendidos foi considerado baixo; entretanto mostrou uma associação positiva com procedimentos como a alta rotação e a anestesia

Despite the fact that it is beneficial, dental treatment can cause anxiety for the patient and the dentist. If verified beyond an acceptable limit, anxiety can prevent the patient to undergo treatment, compromising his quality of life. The aim of this study was to evaluate the profile of patients treated in dental clinics of a teaching institution and their integrated and master's degree clinics from University Veiga de Almeida were interviewed between March and October 2015. The patients answered a questionnaire with socio-economic data and questions to identify the degree of anxiety to dental treatment, using the scale DAS (Dental Anxiety Scale). The sample in¬cluded male (50.4%) aged more than 45 years (51.1%), with income of up to 5 minimum wages (66.9%) and higher level of education (56.4%). Although 88.7% have reported some level of anxiety, this was considered low. There was no statistical difference between the degree of anxiety of men and women (p=0.458). No as¬sociation was found between age, gender, income, level of education, frequency of dental visits and the level of anxiety (p> 0.05). There was a significant association (p = 0.015) between procedures that bother during dental visit, such as high-speed air turbine and anesthesia, and observed anxiety levels. It can be concluded that the level of anxiety of patients was considered low; however, it showed a positive association with procedures such as high-speed air turbine and anesthesia

Edentulism in Brazil: trends, projections and expectations until 2040 / Edentulismo no Brasil: tendências, projeções e expectativas até 2040

Abstract The aim of this study was to examine the edentulism rates in Brazil and make projections for the next years. Data were collected from three national oral health surveys. The percentage of edentulous jaws was calculated. Projections were made for the years 2020, 2030 and 2040, assuming that edentulism follows a logistic function. Population projections were also performed. Annual change in proportion of edentulous jaws was -0.04% for teenagers, -0.96% for adults and 0.76% for the elderly. By 2040, edentulous jaws will be virtually zero among teenagers, 1.77% among adults and 85.96% among the elderly. Teenagers will slightly decrease in number; adults will increase and subsequently decrease; the elderly will continue to increase. In teenagers and adults, the number of edentulous jaws will decrease, being approximately 616,000 in 2040. In the elderly, it will increase alarmingly, reaching over 64 million in 2040. Edentulism is declining in Brazil among teenagers and middle-aged adults, but is still increasing and will continue to increase for the next decades among the elderly.

Resumo O objetivo deste estudo foi examinar as taxas de edentulismo no Brasil e fazer projeções para os próximos anos. Os dados foram coletados de três censos nacionais de saúde bucal. O percentual de arcadas edêntulas foi calculado. Foram feitas projeções para 2020, 2030 e 2040, assumindo que o edentulismo segue uma função logística. Também foram realizadas projeções populacionais. A variação anual da proporção de arcadas edêntulas foi de -0,04% para jovens, -0,96% para adultos e 0,76% para idosos. Até 2040, o percentual de arcadas edêntulas será virtualmente zero entre jovens, 1,77% entre adultos e 85,96% entre idosos. O número de jovens vai diminuir levemente; o de adultos vai aumentar e depois diminuir; e o de idosos vai continuar aumentando. Para jovens e adultos, o número de arcadas edêntulas vai diminuir, aproximando-se de 616.000 em 2040. Para os idosos, este número vai aumentar alarmantemente, alcançando mais de 64 milhões em 2040. O edentulismo está diminuindo no Brasil entre jovens e adultos, mas está aumentando e continuará a aumentar nas próximas décadas entre os idosos.

Protocolo de exame clínico auxiliar ao diagnóstico das lesões dentais não cariosas (LDNC) / Clinical examination protocol to assist the diagnosis of noncarious dental lesions (NCDL)

A perda de tecido duro, ou seja a desmineralização do dente, na região cervical , não associada à cárie, define um grupo de lesões conhecidas como lesões dentárias de origem não cariosa (LDNC). A etiologia das LDNC é considerada multifatorial. Foi proposto que elas se iniciam devido à incidência de forças oclusais cíclicas fora do longo eixo do dente, que causam sua deflexão. Foi encontrada associação entre a presença de LDNC e fatores oclusais como trauma oclusal e facetas de desgaste, o que justifica um acurado exame oclusal do paciente com essas lesões. Devido às dificuldades do clínico em diagnosticar as características oclusais associadas às LDNC, este trabalho tem por objetivo estabelecer um protocolo de exame clínico auxiliar de diagnóstico utilizando um relato de caso clínico como referência. Aos exames extra e intra-orais, verificou-se o tipo de oclusão dentária e suas possíveis relações com as LDNC encontradas, e se quantificou a influência de fatores de risco como consumo de substância ácida, bebidas gaseificadas, fatores ambientais, agentes etiológicos intrínsecos e a oclusão. O protocolo mostrou-se uma ferramenta eficaz para ajudar o clínico e facilitar o diagnóstico das possíveis etiologias das LDNC...

The loss of hard tissue, or desmineralizatio of teeth, in the cervical region, not associated with caries, defines a group of lesions known as non carious dental lesion (NCDL). The etiology of NCDL is considered multifactorial. It has been proposed that they are initiated due to the effect of cyclic occlusal forces outside the long axis of the tooth, which cause its deflection. Association was found between the presence of NCDL and occlusal factors as occlusal trauma and wear facets, which justifies an accurate occlusal examination of patients with these lesions. Considering the difficulties of diagnosing clinical occlusal characteristics associated with NCDL, this work aimed to establish a clinical examination protocol diagnostic aid using a case report as a reference. During extra and intra-oral examinations wasidentified the type of dental occlusion and its possible relations with NCDL, and quantified the influence of risk factors such as consumption of acidic substance, carbonated drink, environmental factors, intrinsic etiologic agents, and occlusion. The proved to be an effective tool to help the clinician and facilitate the diagnosis of possible etiologies of NCDL...

Effect of composite surface treatment and aging on the bond strength between a core build-up composite and a luting agent

Objective The purpose of this study was to assess the influence of conditioning methods and thermocycling on the bond strength between composite core and resin cement. Material and Methods Eighty blocks (8×8×4 mm) were prepared with core build-up composite. The cementation surface was roughened with 120-grit carbide paper and the blocks were thermocycled (5,000 cycles, between 5°C and 55°C, with a 30 s dwell time in each bath). A layer of temporary luting agent was applied. After 24 h, the layer was removed, and the blocks were divided into five groups, according to surface treatment: (NT) No treatment (control); (SP) Grinding with 120-grit carbide paper; (AC) Etching with 37% phosphoric acid; (SC) Sandblasting with 30 mm SiO2 particles, silane application; (AO) Sandblasting with 50 mm Al2O3 particles, silane application. Two composite blocks were cemented to each other (n=8) and sectioned into sticks. Half of the specimens from each block were immediately tested for microtensile bond strength (µTBS), while the other half was subjected to storage for 6 months, thermocycling (12,000 cycles, between 5°C and 55°C, with a dwell time of 30 s in each bath) and µTBS test in a mechanical testing machine. Bond strength data were analyzed by repeated measures two-way ANOVA and Tukey test (α=0.05). Results The µTBS was significantly affected by surface treatment (p=0.007) and thermocycling (p=0.000). Before aging, the SP group presented higher bond strength when compared to NT and AC groups, whereas all the other groups were statistically similar. After aging, all the groups were statistically similar. SP submitted to thermocycling showed lower bond strength than SP without thermocycling. Conclusion Core composites should be roughened with a diamond bur before the luting process. Thermocycling tends to reduce the bond strength between composite and resin cement. .

Influência da deposição de filmes de carbono tipo diamante na infiltração bacteriana pela interface entre implantes e pilares protéticos / Influence of diamond like carbon films in bacterial leakage through implant-abutment interface

O estudo avaliou a influência da deposição de filmes de DLC na infiltração bacteriana pela interface entre pilares protéticos e implantes de hexágono externo (HE) e interno (HI). Também avaliou a aderência microbiana a estes filmes, depositados sobre titânio. A deposição dos filmes foi realizada por PECVD (Deposição Química a Vapor Assistida por Plasma), e sua caracterização foi feita pelas análises de perfilometria mecânica, espectroscopia Raman, rugosidade, análise tribológica, espectroscopia de energia dispersiva e ângulo de contato. Para avaliação da aderência microbiana, lâminas de titânio (N=45; n=15) foram divididas em três grupos: (1) sem filme (controle); (2) com filme de DLC; e (3) com filme de DLC dopado com prata (DLC-Ag). Elas foram suspensas em poços contendo saliva-glicerol e caldo de cultura. Após 48 h de incubação, elas foram agitadas em ultrassom e a suspensão resultante foi diluída e semeada em placas para contagem de microrganismos. Para avaliação da infiltração bacteriana pela interface implante/pilar, conjuntos de implantes e pilares HE e HI (N=180; n=30) foram divididos de acordo com o tratamento da base do pilar: (1) nenhum tratamento (controle); (2) deposição de filme de DLC; e (3) deposição de filme de DLC-Ag. Sob condições assépticas, foi inoculado 1 μL de suspensão de Enterococcus faecalis no interior dos implantes, e os pilares foram parafusados com 20 Ncm. Os conjuntos foram testados para contaminação externa imediata, suspensos em tubos de ensaio contendo caldo de cultura estéril, e acompanhados por cinco dias. A turvação do caldo indicou infiltração bacteriana. Ao final do período, os pilares foram desparafusados e o conteúdo interno dos implantes foi coletado com cone de papel e semeado em placas de Petri. Estas foram levadas a estufa bacteriológica por 24 h para verificação da viabilidade bacteriana e contagem de UFCs. A rugosidade e os dados de log10UFC/mL foram analisados por análise de variância...

This study evaluated the influence of DLC films on bacterial leakage through the interface between abutments and dental implants of external hexagon (HE) and internal hexagon (HI). It also evaluated microbial adhesion to these films deposited on titanium. The deposition of the films was performed by PECVD (Plasma Enhanced Chemical Vapor Deposition), and its characterizations were done by mechanical profilometry, Raman spectroscopy, surface roughness, tribological analysis, energy dispersive spectroscopy and contact angle. To evaluate the microbial adhesion, titanium blades (N=45, n=15) were divided into three groups: (1) without film (control), (2) with DLC film, and (3) with DLC film doped with silver (Ag-DLC). They were suspended in wells containing saliva-glycerol broth. After 48 h incubation they were ultrasonicated and the resulting suspension was diluted and plated for CFU counting. For evaluation of bacterial leakage through implant/abutment interface, sets of implants and abutments (N=180, n=30) were divided according to the treatment of the base of the abutment: (1) no treatment (control); (2) deposition of DLC film, and (3) deposition of Ag-DLC film. Under aseptic conditions, 1 μL of Enterococcus faecalis was inoculated inside the implants, and abutments were tightened to 20 Ncm. The sets were tested for immediate external contamination, suspended in test tubes containing sterile culture broth, and followed for five days. The turbidity of the broth indicated bacterial leakage. At the end of the period, the abutments were removed and the internal content of the implants was collected with paper cone and seeded in Petri dishes. These were incubated for 24 h for assessment of bacterial viability and CFU counting. The roughness and log10CFU/mL data were analyzed by analysis of variance. The bacterial leakage was analyzed by Chi-square test, Fisher exact test, Kaplan-Meier and Log-rank...

Microtensile test in dental research. Controversial aspects in statistical analysis: experimental unit and premature failures / Teste de microtração na pesquisa odontológica. Aspectos controversos na análise estatística: unidade experimental e falhas prematuras

Objetivo: O objetivo dessa pesquisa é apresentar aspectos controversos na condução da análise estatística inferencial quanto à seleção da unidade experimental e quanto ao procedimento adotado diante das falhas pré-teste. Método: Foram avaliadas 87 dissertações e teses na área da odontologia que realizaram ensaio de microtração disponíveis em três universidades públicas do estado de São Paulo: Faculdade de Odontologia da USP (São Paulo, Ribeirão Preto e Bauru), Faculdade de Odontologia da Unesp (Araraquara e São José dos Campos) e Faculdade de Odontologia da Unicamp (Piracicaba e Campinas). Resultados: Quanto à unidade experimental, 34 (39,08%) teses e/ou dissertações utilizaram o “palito” e 53 (60,91%) o “dente/bloco”. Quanto às falhas pré-teste, 9 (10,34%) teses e/ou dissertações atribuíram valor “0”, 6 (6,89%) desconsideraram os palitos, 2 (2,29%) atribuíram o valor mínimo de 2 MPa, 1 (1,14%) atribuiu o valor mínimo de 4 MPa, 1 (1,14%) atribuiu a metade do valor mínimo do grupo e 68 (78,16%) não citaram a ocorrência de falhas pré-testes. Conclusão: Quanto à unidade experimental, atualmente considera-se como unidade experimental o dente (ou o bloco cerâmico) e não o palito. Quanto à ocorrência de falhas pré-teste, considera-se: atribuição de um valor mínimo de resistência adesiva na condição experimental ou grupo considerado; expressar o número e percentual dos casos de falhas em cada condição experimental; qual tipo de falha foi incluído na análise estatística e informar exatamente como os autores procederam em relação ao delineamento experimental (unidade experimental e falhas pré-teste).

Objectives: The aim of this study was to present the controversial aspects in performing inferential statistical analysis with regard to selection of the experimental unit and procedures adopted in the case of pre-test failures. Methods: Eighty-seven dissertations and theses in the field of dentistry were evaluated, for which microtensile testing was made available at three public Universities in the State of São Paulo were performed, namely: School of Dentistry, USP; School of Dentistry, Unesp (Araraquara and São José dos Campos) and the Piracicaba School of Dentistry (Unicamp). Results: Regarding the experimental unit, 34 (39.08%) theses and/or dissertations used the “stick” and 53 (60.91%) the “tooth/block” type. With regard to pretest failures, 9 (10.34%) theses and/or dissertations attributed the value “0”, 6 (6.89%) disregarded the sticks, 2 (2.29%) attributed the minimum value of 2 MPa, 1 (1.14%) the minimum value of 4 MPa, 1 (1.14%) attributed half the minimum value of the group and 68 (78.16%) did not mention the occurrence of pretest failures. Conclusion: At present the experimental unit is considered to be the tooth (or ceramic block) and not the stick. As it relates to pre-test failures, the following are considered: attribution of a minimum bond strength value under experimental condition or in the group considered, an expressed number and percentage of cases of failures under each experimental condition; failures included in the statistical analysis and detailed explantion of how the authors performed with regard experimental designs (experimental unit and premature failures).

Influência da deposição de filmes de carbono tipo diamante na infiltração bacteriana pela interface entre implantes e pilares protéticos / Influence of diamond like carbon films in bacterial leakage through implant-abutment interface

O estudo avaliou a influência da deposição de filmes de DLC na infiltração bacteriana pela interface entre pilares protéticos e implantes de hexágono externo (HE) e interno (HI). Também avaliou a aderência microbiana a estes filmes, depositados sobre titânio. A deposição dos filmes foi realizada por PECVD (Deposição Química a Vapor Assistida por Plasma), e sua caracterização foi feita pelas análises de perfilometria mecânica, espectroscopia Raman, rugosidade, análise tribológica, espectroscopia de energia dispersiva e ângulo de contato. Para avaliação da aderência microbiana, lâminas de titânio (N=45; n=15) foram divididas em três grupos: (1) sem filme (controle); (2) com filme de DLC; e (3) com filme de DLC dopado com prata (DLC-Ag). Elas foram suspensas em poços contendo saliva-glicerol e caldo de cultura. Após 48 h de incubação, elas foram agitadas em ultrassom e a suspensão resultante foi diluída e semeada em placas para contagem de microrganismos. Para avaliação da infiltração bacteriana pela interface implante/pilar, conjuntos de implantes e pilares HE e HI (N=180; n=30) foram divididos de acordo com o tratamento da base do pilar: (1) nenhum tratamento (controle); (2) deposição de filme de DLC; e (3) deposição de filme de DLC-Ag. Sob condições assépticas, foi inoculado 1 μL de suspensão de Enterococcus faecalis no interior dos implantes, e os pilares foram parafusados com 20 Ncm. Os conjuntos foram testados para contaminação externa imediata, suspensos em tubos de ensaio contendo caldo de cultura estéril, e acompanhados por cinco dias. A turvação do caldo indicou infiltração bacteriana. Ao final do período, os pilares foram desparafusados e o conteúdo interno dos implantes foi coletado com cone de papel e semeado em placas de Petri. Estas foram levadas a estufa bacteriológica por 24 h para verificação da viabilidade bacteriana e contagem de UFCs. A rugosidade e os dados de log10UFC/mL foram analisados por análise de variância. A infiltração ....

This study evaluated the influence of DLC films on bacterial leakage through the interface between abutments and dental implants of external hexagon (HE) and internal hexagon (HI). It also evaluated microbial adhesion to these films deposited on titanium. The deposition of the films was performed by PECVD (Plasma Enhanced Chemical Vapor Deposition), and its characterizations were done by mechanical profilometry, Raman spectroscopy, surface roughness, tribological analysis, energy dispersive spectroscopy and contact angle. To evaluate the microbial adhesion, titanium blades (N=45, n=15) were divided into three groups: (1) without film (control), (2) with DLC film, and (3) with DLC film doped with silver (Ag-DLC). They were suspended in wells containing saliva-glycerol broth. After 48 h incubation they were ultrasonicated and the resulting suspension was diluted and plated for CFU counting. For evaluation of bacterial leakage through implant/abutment interface, sets of implants and abutments (N=180, n=30) were divided according to the treatment of the base of the abutment: (1) no treatment (control); (2) deposition of DLC film, and (3) deposition of Ag-DLC film. Under aseptic conditions, 1 μL of Enterococcus faecalis was inoculated inside the implants, and abutments were tightened to 20 Ncm. The sets were tested for immediate external contamination, suspended in test tubes containing sterile culture broth, and followed for five days. The turbidity of the broth indicated bacterial leakage. At the end of the period, the abutments were removed and the internal content of the implants was collected with paper cone and seeded in Petri dishes. These were incubated for 24 h for assessment of bacterial viability and CFU counting. The roughness and log10CFU/mL data were analyzed by analysis of variance. The bacterial leakage was analyzed by Chi-square test, Fisher exact test, Kaplan-Meier and Log-rank. The level of significance was 5%. ...

A rationale method for evaluating unscrewing torque values of prosthetic screws in dental implants

OBJECTIVES: Previous studies that evaluated the torque needed for removing dental implant screws have not considered the manner of transfer of the occlusal loads in clinical settings. Instead, the torque used for removal was applied directly to the screw, and most of them omitted the possibility that the hexagon could limit the action of the occlusal load in the loosening of the screws. The present study proposes a method for evaluating the screw removal torque in an anti-rotational device independent way, creating an unscrewing load transfer to the entire assembly, not only to the screw. MATERIAL AND METHODS: Twenty hexagonal abutments without the hexagon in their bases were fixed with a screw to 20 dental implants. They were divided into two groups: Group 1 used titanium screws and Group 2 used titanium screws covered with a solid lubricant. A torque of 32 Ncm was applied to the screw and then a custom-made wrench was used for rotating the abutment counterclockwise, to loosen the screw. A digital torque meter recorded the torque required to loosen the abutment. RESULTS: There was a significant difference between the means of Group 1 (38.62±6.43 Ncm) and Group 2 (48.47±5.04 Ncm), with p=0.001. CONCLUSION: This methodology was effective in comparing unscrewing torque values of the implant-abutment junction even with a limited sample size. It confirmed a previously shown significant difference between two types of screws.

The need for complete dentures in Brazil: an epidemiological approach for the next 10 years

The only two censuses on oral health (Levantamento Epidemiológico em Saúde Bucal em 1986 e Projeto em Saúde Bucal de 2003) show a tendency in the reduction of edentulous patients in Brazil. The aim of this article was to estimate the variation in rates of the need for dentures in Brazil in 2010 and 2020. The projection was obtained from a linear variation carried out between the 1986 and 2003 censuses. A formula was used to calculate the result, which showed a strong trend in the decline of the number of edentulous patients until 2020. After the result analyses, it was found that by 2020 the need for complete denture for people between 15 and 74 years old will be none. Unfortunately, the only two censuses on oral health do not give us sufficient data to show a reliable projection of edentulous patients in Brazil

Influence of application site of provisional cement on the marginal adaptation of provisional crowns

Introduction: Marginal discrepancies may lead to cement washout and marginal leakage, damaging periodontal and pulp tissues or causing premature loss of the restoration. Purpose: This study evaluated the influence of application site of provisional cement on the marginal adaptation of provisional crowns. Material and Methods: Four different application sites of provisional cement (Temp Bond NE, Kerr Corporation) were used for cementation of provisional crowns on phantom teeth prepared for full crown restorations, performing 4 experimental groups (n=10): cement applied to all internal surfaces of the crown (CAO); cement applied to all internal surfaces of the crown, except for the occlusal surface (CA); cement applied to the cervical crown margin (CM); and cement applied to the cervical tooth margin (TM). A comparison microscope (Mitutoyo America Corporation) was used to measure the distances between the internal tangents of two circular marks, one made on the provisional crown and one made apical to the tooth preparation margin, in areas corresponding to buccal, lingual, mesial and distal surfaces. Marginal adaptation was determined before and after cementation, with 0.0001-mm accuracy. Data were analyzed statistically by ANOVA and Tukey’s test at 5% significance level. Results: Mean values of marginal opening obtained for each group were: CAO: 145 µm; CA: 67 µm; CM: 46 µm; TM: 34 µm. CA, CM and TM presented significantly lower marginal openings than CAO (p<0.05). Conclusion: complete filling of the crown with provisional cement, including the occlusal surface, provided grater marginal discrepancies when compared to the other methods evaluated.