The effects of heating on the physicochemical properties of tricalcium silicate root canal sealers

Abstract This study evaluated the effect of heating on the physicochemical properties and surface changes of tricalcium silicate sealers. Three tricalcium silicate root canal sealers (Bio-C Sealer, BioRoot-RCS, EndoSequence BC Sealer), and one epoxy resin-based sealer (AH Plus; control) were tested. The effect of heating on setting time (ST) and flowability were assessed according to ANSI/ADA 57 and ISO 6876 standards. Solubility and dimensional change (DC) of the set sealers were evaluated at 24 hours and after 30 days; the pH of the water used in the DC testing was also measured. Tests were repeated with heated sealers in an oven at 100 °C for 1 min. SEM and EDS analysis were performed. Data were analyzed using One-Way ANOVA and Tukey post-hoc tests (α=5%). Heating decreased the ST for AH Plus and EndoSequence (p<0.05). Heating reduced flowability (p<0.05) and increased pH for AH Plus (p<0.05). The solubility of Bio-C (dried specimens) was not in accordance with the ANSI/ADA standard. The solubility of EndoSequence was significantly higher (p<0.05) when it was heated and dried after 30 days. DC of Bio-C (24 h and 30 days), BioRoot-RCS (30 days) and AH Plus (24 h and 30 days) were not in accordance with the standards. SEM and EDS analysis showed significant changes in sealer microstructure after heating. In conclusion, heating decreased the ST and increased the solubility of EndoSequence BC sealer. No significant changes in flowability, DC, and pH were identified for all three tricalcium silicate sealers after heat application. However, all sealers had significant surface changes.

Resumo Este estudo avaliou o efeito do aquecimento nas propriedades físico-químicas e nas alterações superficiais de cimentos de silicato tricálcico. Três cimentos endodônticos de silicato tricálcico (Bio-C Sealer, BioRoot-RCS, EndoSequence BC Sealer) e um cimento à base de resina epóxi (AH Plus) foram testados para avaliar o efeito do aquecimento no tempo de presa (TP) e escoamento de acordo com as normas ANSI/ADA 57 e ISO 6876. A solubilidade e alteração dimensional (AD) dos cimentos foram avaliadas após 24 horas e 30 dias. O pH da água usada no teste de AD também foi medido. Os testes foram repetidos com cimentos aquecidos em um forno a 100 °C por 1 min. Análises em MEV e EDS foram realizadas. Os dados foram analisados pelos testes de ANOVA-1 via e post hoc de Tukey (α=5%). O aquecimento diminuiu o TP para AH Plus e EndoSequence (p<0,05). O aquecimento reduziu o escoamento (p<0,05) e aumentou o pH do AH Plus (p<0,05). A solubilidade do Bio-C (amostras desidratadas) não estava de acordo com o padrão ANSI/ADA. A solubilidade da EndoSequence foi significativamente maior (p<0,05) quando aquecida e desidratada após 30 dias. As AD de Bio-C (24 h e 30 dias), BioRoot-RCS (30 dias) e AH Plus (24 h e 30 dias) não estavam de acordo com as normas ADA e ISO. A análise em MEV e EDS mostrou alterações significativas na estrutura dos cimentos após aquecimento. Em conclusão, o aquecimento diminuiu o TP e aumentou a solubilidade do cimento EndoSequence BC. Não foram identificadas mudanças significativas no escoamento, AD e pH para os cimentos de silicato tricálcico após aquecimento. Porém, todos os cimentos tiveram alterações significativas na superfície.

Dental and composite resin discoloration induced by different hydraulic calcium silicate-based cements: two-year in vitro assessment

Abstract Few long-term studies assess the discoloration induced by hydraulic calcium silicate-based cement on dental structures. In addition, as far as we know, no long-term study has assessed the discoloration induced by these cement on composite resin. Objective This in vitro study aimed to assess, during a period of two years, the discoloration potential of different hydraulic calcium silicate-based cements (hCSCs) on the enamel/dentin structure and composite resin restoration. Methodology A total of 40 enamel/dentin discs were obtained from bovine incisors, and 40 composite resin discs (10 mm in diameter × 2 mm thick) were fabricated. A 0.8 mm-deep cavity was made in the center of each disc and filled with the following hCSCs (n=10): Original MTA (Angelus); MTA Repair HP (Angelus); NeoMTA Plus (Avalon); and Biodentine (Septodont). An initial color measurement was performed (T0 - baseline). After 7, 15, 30, 45, 90, 300 days, and two years, new color measurements were performed to determine the color (ΔE00), lightness (ΔL'), chroma (ΔC'), hue differences (ΔH'), and whiteness index (WID). Results For enamel/dentin, the ΔE00 was significant among groups and periods (p<0.05). NeoMTA Plus had the greatest ΔE00. The NeoMTA Plus group had the greatest ΔE00 after two years for composite resin. Significant reduction in lightness was observed for all groups after two years (p<0.05). The most significant WID values were observed after 30 days for Biodentine (enamel/dentin) and MTA Repair HP groups (composite resin) (p<0.05). Conclusions The hCSCs changed the colorimetric behavior of both substrates, leading to greater darkening over time. The Bi2O3 in the Original MTA seems relevant in the short periods of color change assessment.

Effect of dental tissue thickness on the measurement of oxygen saturation by two different pulse oximeters

Abstract This study aimed to evaluate the influence of different dental tissue thickness on the measurement of oxygen saturation (SpO2) levels in high (HP) and low (LP) blood perfusion by comparing the values obtained from two different pulse oximeters (POs) - BCI and Sense 10. Thirty freshly extracted human teeth had their crowns interposed between the POs and an optical simulator, which emulated the SpO2 and heart beats per minute (bpm) at HP (100% SpO2/75 bpm) and LP (86% SpO2/75 bpm) modes. Afterwards, the palatine/lingual surfaces of the dental crowns were worn with diamond drills. The reading of SpO2 was performed again using the POs alternately through the buccal surface of each dental crown. Data were analyzed by the Wilcoxon, Mann-Whitney and Kendall Tau-b tests (α=5%). The results showed significant difference at the HP and LP modes in the SpO2 readouts through the different dental thicknesses with the use of BCI, and at the LP mode with the use of Sense 10, which had a significant linear correlation (p<0.0001) and lower SpO2 readout values in relation to the increase of the dental thickness. Irrespective of tooth thickness, Sense 10 had significantly higher readout values (p<0.0001) than BCI at both perfusion modes. The interposition of different thicknesses of enamel and dentin influenced the POs measurement of SpO2, specially at the low perfusion mode. The POs were more accurate in SpO2 measurement when simulated perfusion levels were higher.

Resumo Este estudo avaliou a influência de diferentes espessuras de esmalte e dentina na medição dos níveis de saturação de oxigênio (SpO2) em alta (HP) e baixa (LP) perfusão sanguínea, comparando os valores obtidos em dois oxímetros de pulso (OPs) diferentes, BCI e Sense 10. Trinta dentes recém-extraídos de humanos tiveram suas coroas interpostas entre os OPs e um simulador óptico, que simulava a SpO2 e os batimentos cardíacos por minuto (bpm) nos modos de HP (100% SpO2 / 75 bpm) e LP (86% SpO2 / 75 bpm). Após, as superfícies palatinas / linguais dos dentes foram desgastadas com brocas de diamantadas. A leitura da SpO2 foi realizada novamente usando os dois OPs alternadamente através da face vestibular de cada coroa dental. Os dados foram analisados ​​pelos testes Wilcoxon, Mann-Whitney e Kendall Tau-b (α = 5%). Os resultados mostraram diferença significativa nos modos HP e LP nas leituras de SpO2 através das diferentes espessuras dentárias com o uso do BCI, e no modo LP com o uso do Sense 10, que teve correlação linear significativa (p <0,0001) e menores valores de leitura de SpO2 em relação ao aumento da espessura dentária. Independentemente da espessura do dente, o Sense 10 apresentou valores de leitura significativamente maiores (p <0,0001) do que o BCI em ambos os modos de perfusão. A interposição de diferentes espessuras de esmalte e dentina influenciaram a mensuração da SpO2 pelos OPs, especialmente no modo de baixa perfusão. Os POs foram mais precisos na mensuração da SpO2 quando os níveis simulados de perfusão foram maiores.

Guided Endodontics in Root Canals with Complex Access: Two Case Reports

Abstract This article reported two clinical cases in which the guided endodontics was used to perform the access to the root canals. The first case presents a 40-year-old female with a history of pain related to the left maxillary canine. After radiographic examination, the presence of severe calcification up to the apical third of the root canal, associated with a periapical radiolucency, was noted. In the second case, an 85-year-old male was referred to our service with pain upon palpation, at the right mandibular first molar. The radiographic images revealed the presence of endodontic treatment and a fiberglass post in the distal root canal, which was associated with extrusion of the filling material and a periapical lesion. The 3D-guides were planned based on cone beam computed tomography and intraoral digital scanning, which were aligned using a specific software. Therefore, implant drills could be guided up to the root canal length required for each case. In the first case, a surgical root canal was created and the patient was free of signs and symptoms after the treatment was completed. In the second case, it was observed that the fiber post was worn by the drill, allowing free access to the filling material. It was possible to perform the endodontic reintervention in a more predictable way and in less time. In both cases, the use of the guided endodontics allowed the preservation of a large part of the dental structure. The procedures were performed faster, without the occurrence of fractures and perforations.

Resumo Este artigo relatou dois casos clínicos em que a endodontia guiada foi utilizada para realizar o acesso aos canais radiculares. O primeiro caso apresenta uma mulher de 40 anos com história de dor relacionada ao canino superior esquerdo. Após exame radiográfico, notou-se a presença de calcificação acentuada até o terço apical do canal radicular, associada a radioluscência periapical. No segundo caso, um homem de 85 anos foi encaminhado ao nosso serviço com dor à palpação no primeiro molar inferior direito. As imagens radiográficas revelaram a presença de tratamento endodôntico e pino de fibra de vidro no canal radicular distal, que estava associado à extrusão do material obturador e lesão periapical. Os guias-3D foram planejados com base em tomografia computadorizada de feixe cônico e escaneamento intraoral digital, os quais foram alinhados por meio de um software específico. Desta forma, brocas de implante puderam ser guiadas até o comprimento necessário do canal radicular para cada caso. No primeiro caso, foi confeccionado um canal radicular cirúrgico e o paciente ficou sem sinais e sintomas após o término do tratamento. No segundo caso, observou-se que o pino de fibra foi desgastado pela broca, permitindo o livre acesso ao material obturador. Foi possível realizar a reintervenção endodôntica de forma mais previsível e em menos tempo. Em ambos os casos, o uso da endodôntica guiada permitiu a preservação de grande parte da estrutura dentária. Os procedimentos foram realizados com maior agilidade, sem a ocorrência de fraturas e perfurações.

Fracture resistance of simulated immature teeth reinforced with different mineral aggregate-based materials

Abstract This study assessed the fracture resistance of simulated immature teeth reinforced with calcium aluminate cement (CAC) or mineral trioxide aggregate (MTA) containing calcium carbonate nanoparticles (nano-CaCO3). The microstructural arrangement of the cements and their chemical constitution were also evaluated. Forty-eight canines simulating immature teeth were distributed into 6 groups (n=8): Negative control - no apical plug or root canal filling; CAC - apical plug with CAC; CAC/nano-CaCO3 - apical plug with CAC+5% nano-CaCO3; MTA - apical plug with MTA; MTA/nano-CaCO3 - apical plug with MTA+5% nano-CaCO3; and Positive control - root canal filling with MTA. The fracture resistance was evaluated in a universal testing machine. Samples of the cements were analyzed under Scanning Electron Microscope (SEM) to determine their microstructural arrangement. Chemical analysis of the cements was performed by Energy Dispersive X-ray Spectroscopy (EDS). The fracture resistance of CAC/nano-CaCO3 was significantly higher than the negative control (p<0.05). There was no significant difference among the other groups (p>0.05). Both cements had a more regular microstructure with the addition of nano-CaCO3. MTA samples had more calcium available in soluble forms than CAC. The addition of nano-CaCO3 to CAC increased the fracture resistance of teeth in comparison with the non-reinforced teeth. The microstructure of both cements containing nano-CaCO3 was similar, with a more homogeneous distribution of lamellar- and prismatic-shaped crystals. MTA had more calcium available in soluble forms than CAC.

Resumo Este estudo avaliou a resistência à fratura de dentes imaturos simulados reforçados com cimento de aluminato de cálcio (CAC) ou trióxido agregado mineral (MTA) contendo nanopartículas de carbonato de cálcio (nano-CaCO3). O arranjo microestrutural dos cimentos e sua constituição química também foram avaliados. Quarenta e oito caninos simulando dentes imaturos foram distribuídos em 6 grupos (n=8): Controle negativo - sem plug apical ou obturação do canal radicular; CAC - plug apical com CAC; CAC/nano-CaCO3 - plug apical com CAC + 5% nano-CaCO3; MTA - plug apical com MTA; MTA/nano-CaCO3 - plug apical com MTA + 5% nano-CaCO3; e Controle positivo - obturação dos canais radiculares com MTA. A resistência à fratura foi avaliada em máquina universal de ensaios. Amostras dos cimentos foram analisadas em Microscópio Eletrônico de Varredura (MEV) para determinar seu arranjo microestrutural. A análise química dos cimentos foi realizada por Espectroscopia de Energia Dispersiva de Raio-X (EDS). A resistência à fratura de CAC/nano-CaCO3 foi significativamente maior do que o controle negativo (p<0,05). Não houve diferença significativa entre os outros grupos (p>0,05). Ambos os cimentos apresentaram microestrutura mais regular com a adição de nano-CaCO3. As amostras de MTA apresentaram mais cálcio disponível em formas solúveis do que CAC. A adição de nano-CaCO3 ao CAC aumentou a resistência à fratura dos dentes em comparação aos dentes não reforçados. A microestrutura de ambos os cimentos contendo nano-CaCO3 foi semelhante, com uma distribuição mais homogênea de cristais de formato lamelar e prismático. MTA apresentou mais cálcio disponível nas formas solúveis do que CAC.

Accuracy of cone-beam computed tomography in measuring the thickness of radicular dentin

Abstract The purpose of this study was to evaluate the accuracy of Cone-Beam Computed Tomography (CBCT) in measuring radicular dentin thickness focused on intraradicular post placement planning treatment. Ten single-rooted human premolars were selected. The teeth were divided into three segments (cervical, middle and apical). The coronal face of the apical and middle sections was selected for the dentin thickness assessment; which was measured from the external root surface to the root canal wall, on the buccal, lingual, mesial, and distal surfaces of each tooth. In situ anatomical measurement was the reference standard, and the corresponding axial CBCT imaging were evaluated by the i-CAT software. The one-way ANOVA test and the Bonferroni post hoc test were applied to compare the groups (p>0.05). CBCT imaging measurements (p=0.003) overestimated the radicular dentin thickness compared to the reference standard. Descriptive analysis showed that the greatest difference between the reference standard and the tomographic measurement means were 0.20 mm. One-way ANOVA test found the statistical significant difference among group's measurements. Bonferroni correction demonstrated statistically significant difference only related lingual surface for the CBCT imaging measurements. CBCT imaging measurements overestimated the radicular dentin thickness. However, the measurement difference was clinically acceptable.

Resumo O objetivo deste estudo foi avaliar a precisão da Tomografia Computadorizada de Feixe Cônico (TCFC) na mensuração da espessura da dentina radicular no planejamento de tratamento envolvendo a cimentação de pinos intrarradiculares. Dez pré-molares humanos unirradiculares foram selecionados. Os dentes foram divididos em três segmentos (cervical, médio e apical). A face coronal dos terços apical e médio foi selecionada para a avaliação da espessura da dentina; que foi medida a partir da superfície externa da raiz até a parede do canal radicular, nas superfícies vestibular, lingual, mesial e distal de cada dente. A medida anatômica in situ foi o padrão de referência, e a imagem de TCFC axial correspondente foi avaliada pelo software i-CAT. O teste de 1-fator ANOVA e o teste post hoc de Bonferroni foram aplicados para comparar os grupos (p>0,05). As medidas de imagem da TCFC (p=0,003) superestimaram a espessura da dentina radicular em comparação a referência padrão. A análise descritiva mostrou que a maior diferença entre a referência padrão e a medida tomográfica foi de 0,20 mm. O teste ANOVA encontrou a diferença de significância estatística entre as medidas do grupo. A correção de Bonferroni demonstrou diferença estatisticamente significante apenas relacionada às medidas de imagem da TCFC. A medida de imagem da TCFC superestimou a espessura da dentina radicular. No entanto, a diferença de medição foi clinicamente aceitável.

Influence of phosphate buffered saline on the bond strength of endodontic cement to dentin

Aim: To analyze the influence of exposure and time of exposure to phosphate buffered saline (PBS) on the push-out bond strength (BS) of Biodentine to dentine. Methods: Eighty 2-mm-thick dentin discs were obtained from transversal sections of human teeth roots. The space of the canal was enlarged using #2-#5 Gates-Glidden burs to obtain 1.3-mm-diameter standardized cavities. The discs were immersed in 17% EDTA followed by 1% NaOCl and dried. The spaces of the canals were filled with Biodentine and the samples were divided into 2 groups (n=40) according to the storage: G1: exposure to moistened cotton pellet; G2: exposure to PBS. After 30 min, 1, 3 and 28 days, 10 samples of each group were subjected to the push-out test. Data were analyzed using ANOVA and Tukey test (p < 0.05). Results: The specimens exposed to PBS had lower BS (p < 0.05), except for the 1-day period (p = 0.6017). In specimens of Group 1 the BS increased up to 3 days (p < 0.05). In specimens in Group 2, the BS increased from 30 min to 1 day (p < 0.0001) and remained stable up to 3 days (p = 0.9876). At 28 days, a significant decrease was observed in the BS values of both groups (p < 0.05). Conclusions: The exposure of Biodentine to PBS led to lower BS values. In general, the BS increased gradually up to 3 days and reduced at 28 days.

Avaliação ex vivo da infiltração coronária em canais obturados com MTA FILLAPEX e AH Plus / Ex vivo evaluation of coronal leakage in root canals filled with MTA FILLAPEX and AH Plus

O objetivo deste estudo foi avaliar a infiltração coronária em canais obturados com AH Plus e MTA FILLAPEX. Trinta pré-molares unirradiculados foram divididos aleatoriamente em 2 grupos (n = 15) de acordo com o cimento obturador utilizado: G1: MTA FILLAPEX e G2: AH Plus. O teste de infiltração do corante nanquim foi conduzido sob pressão de 60 KPa, por 8 min. Após diafanização, foi avaliada a penetração do corante nos terços radiculares. Houve infiltração em 8 e 7 amostras dos G1 e G2, respectivamente. Em nenhuma amostra do G2, o corante atingiu o terço apical. Em quatro amostras do G1, o corante foi visualizado no terço apical. O AH Plus demonstrou uma qualidade de selamento superior ao MTA FILLAPEX.

The aim of this study was evaluate the coronal leakage in root canals filled with AH Plus and MTA FILLAPEX. Thirty single-rooted premolars were randomly divided into two experimental groups (n = 15) according to the sealer used: G1: MTA FILLAPEX and G2: AH Plus. The dye leakage test ink was conducted under pressure of 60 kPa for 8 min. After diaphanization, the dye penetration was evaluated by root thirds. Results: Eight samples form G1 and seven samples from G2 showed infiltration. In any sample from G2, the dye reached the apical third. In four samples from G1, the dye was visualized in the apical third. The AH Plus showed a superior sealing quality of the MTA FILLAPEX.

The sealing ability of MTA apical plugs exposed to a phosphate-buffered saline

OBJECTIVE: The aim of this study was to evaluate the influence of exposure of the mineral trioxide aggregate (MTA) - with and without calcium chloride (CaCl2) - to phosphate-buffered saline (PBS) on the apical microleakage using a glucose leakage system. MATERIAL AND METHODS: Sixty root segments were randomly divided into 4 experimental groups (n=15). After resecting the apical segments and enlarging the canals with Gates-Glidden drills, the apical cavities were filled with MTA with or without CaCl2 and the root canals were dressed with a moistened cotton pellet or PBS, as follows: 1) MTA/cotton pellet; 2) MTA/PBS; 3) MTA+10%CaCl2/cotton pellet; 4) MTA+10%CaCl2/PBS. All root segments were introduced in floral foams moistened with PBS. After 2 months, all root segments were prepared to evaluate the glucose leakage along the apical plugs. The amount of glucose leakage was measured following an enzymatic reaction and quantified by a spectrophotometer. Four roots were used as controls. The data were analyzed using Kruskal-Wallis and Mann-Whitney tests (p<0.05). RESULTS: There were no differences between groups 1 and 2 (p>0.05), and 3 and 4 (p>0.05). The addition of CaCl2 to the MTA significantly decreased its sealing ability (p<0.05). CONCLUSION: The interaction with PBS did not improve the MTA sealing ability. The addition of CaCl2 to the MTA negatively influenced the apical seal. .

Tratamento odontológico em pacientes com comprometimento cardiovascular / Dental treatment in patients with cardiovascular disease

Introdução: A correta avaliação de pacientes com comprometimento cardiovascular baseia-se numa minuciosa anamnese e no conhecimento prévio das principais desordens coronarianas e suas seqüelas. Objetivo: Este artigo revisou conceitos e características de diversas doenças coronarianas, como cardiopatia isquêmica, angina do peito, insuficiência cardíaca congestiva, arritmia e bradicardia. Revisão da literatura e conclusão: Complicações como o infarto do miocárdio e a endocardite bacteriana foram descritas com enfoque nos procedimentos clínicos odontológicos. O manejo dessas informações é importante na determinação do risco cardíaco dos pacientes, a fim de classificá-lo como elevado, moderado ou mínimo. O profissional de odontologia deve planejar as consultas clínicas de acordo com o risco individual preestabelecido. Consultas de curta duração e a limitação dos níveis de estresse e ansiedade, com uso de medicamentos antiansiolíticos e sedação complementar, podem ser importantes para um trans e pósoperatório sem complicações. Os procedimentos emergenciais, nos casos em que as alterações coronarianas ocorrem durante o procedimento clínico, foram também discutidos.

Introduction: The correct evaluation of patients with cardiovascular disease is based on a careful anamnesis and on the previous knowledge of the main coronary diseases and its sequels. Objective: This article revised the concepts and characteristics of diverse heart illnesses as the ischemic cardiopathy, chest angina, congestive cardiac insufficiency, arrhythmia and bradycardia. Literature review and conclusion: Complications like myocardium infarct and bacterial endocarditis were described focusing the dental clinical procedures. The handling of this information is important during the determination of the cardiac risk of each patient, classifying as high, moderate, or minimum risk. Dental professionals must plan the clinical appointments according to preestablished patient´s risk. Short duration appointments and the limitation of the stress and anxiety levels with the use of anti-anxiolytic medicines and complementary sedation can be important for a transoperative and postoperative without complications. The urgent procedures that occurred during the clinical trial in patients with coronary disease were also discussed.

Medidas de prevenção pré e pós-exposição a acidentes perfurocortantes na prática odontológica / Pre and post-exposure preventive measures to injuries caused by percutaneous instruments during dental practice

Objetivos: O objetivo deste estudo foi determinar a prevalência de acidentes com instrumentos perfurocortantes entre odontólogos, verificar o grau de utilização de equipamentos de proteção individual (EPI) e a atitude tomada frente aos acidentes ocorridos. Metodologia: A amostra foi composta por cirurgiões-dentistas, que atuam no Estado de Santa Catarina e que freqüentaram cursos de atualização profissional na UFSC em 2005. Os dados foram coletados através de questionário semi-estruturado auto-aplicável sobre informações gerais de prevenção, utilização de EPI e ocorrência de acidentes. Resultados: Dos 80 profissionais que responderam ao questionário 73% já haviam sofrido pelo menos um acidente. A prevalência de uso rotineiro de EPI foi: luvas e máscaras (100%); óculos (96%); jaleco (97%); gorro (52%); isolamento absoluto (56%) e sobre luva (1%). A falta de uso de EPI não foi citada como principal responsável pelos acidentes, mas sim, a falta de atenção (71%) e a pressa (30%) durante os procedimentos clínicos. Apenas 22% dos entrevistados com acidentes submeteram-se às medidas de prevenção pós-exposição; a maioria limitou-se a lavar o local afetado (69%). Os materiais e instrumentais que mais causaram acidentes foram: brocas, agulhas anestésicas, curetas, alavancas, lâminas de bisturi e limas de endodontia. Conclusão: Este estudo sugere que existe necessidade de maior orientação quanto a medidas adicionais de prevenção e da correta atitude a ser tomada diante da ocorrência de acidentes.

Purpose: The aim of this study was to determine the prevalence of injuries caused by percutaneous instruments among dentists, verify the use of equipment for individual protection (EPI) and the measures taken after the accident. Methods: The sample was composed by dentists, who worked in Santa Catarina state and attended continuing education courses at UFSC in 2005. Data were collected by means of a self-applied and semi-structured questionnaire on general information about prevention, use of EPI, and occurrence of accidents. Results: Eighty dentists answered the questionnaire and 73% had at least one accident. The prevalence of routine use of EPI was: disposable gloves and masks (100%); eyeglasses (96%); gowns (97%); caps (52%), and rubber dam (56%). Omission of EPI use was not the main reason for accidents, but lack of attention (71%) and hurry (35%) were mostly cited. Only 22% of dentists were submitted to post-exposure preventive measures after accidents; most dentists only washed the injury (69%). The materials and instruments mostly reported as the cause of accidents were: drills, needles, curettes, root elevators, knife blades, and endodontic files. Conclusion: This study suggests that it is necessary to improve the orientation and awareness of dentists on the correct post-exposure management of injuries caused by percutaneous instruments.