ABSTRACT Tooth bleaching is a technique of choice to obtain a harmonious smile, but bleaching agents may damage the dental pulp. Objective: This study evaluated the inflammatory responses of human dental pulp after the use of two bleaching techniques. Material and Methods: Pulp samples were collected from human third molars extracted for orthodontic reasons and divided into three groups: control - no tooth bleaching (CG) (n=7); at-home bleaching with 15% carbamide peroxide (AH) (n = 10), and in-office bleaching with 38% hydrogen peroxide (IO) (n=12). Pulps were removed and stained with hematoxylin-eosin for microscopic analysis of inflammation intensity, collagen degradation, and pulp tissue organization. Immunohistochemistry was used to detect mast cells (tryptase+), blood vessels (CD31+), and macrophages (CD68+). Chi-square, Kruskal-Wallis, and Mann Whitney tests were used for statistical analysis. The level of significance was set at p<.05. Results: The inflammation intensity and the number of macrophages were significantly greater in IO than in AH and CG (p<0.05). The results of CD31+ (blood vessels per mm2) were similar in CG (61.39±20.03), AH (52.29±27.62), and IO (57.43±8.69) groups (p>0.05). No mast cells were found in the pulp samples analyzed. Conclusion: In-office bleaching with 38% hydrogen peroxide resulted in more intense inflammation, higher macrophages migration, and greater pulp damage then at-home bleaching with 15% carbamide peroxide, however, these bleaching techniques did not induce migration of mast cells and increased the number of blood vessels.

Protocolos terapêuticos aceitáveis em odontologia dependem de resultados observados com a proservação. Erros de procedimentos operatórios podem ocorrer e representam fatores de risco capazes de comprometer um dente ou um implante dentário. O objetivo deste artigo é detectar os erros de procedimentos operatórios em dentes tratados endodonticamente e implantes dentários por meio de tomografia computadorizada de feixe cônico. Oitocentos e dezesseis (816) exames tomográficos foram realizados entre Janeiro de 2009 e Outubro de 2010, e apenas aqueles que apresentaram dentes tratados endodonticamente e/ou implantes dentários foram selecionados. A amostra final envolveu 195 exames tomográficos (n=200 dentes e 200 implantes dentários), 72 do gênero masculino, 123 do gênero feminino, com idade média de 51 anos. Em dentes tratados endodonticamente os erros de procedimentos operatórios incluídos foram: subobturação, sobreobturação, e perfuração radicular; enquanto que, para implantes dentários foram incluídos: roscas de implantes expostas, implantes em contato com estruturas anatômicas, e em contato com dentes adjacentes. O nível de significância foi estabelecido em α=5%. Subobturações, sobreobturações e perfurações radiculares foram detectadas em 33,5%, 8% e 4,5%, respectivamente. Implantes dentários com roscas expostas, em contato com estruturas anatômicas, e em contato com dentes adjacentes apresentaram valores de 37,5%, 13% e 6,5%, respectivamente. Erros de procedimentos operatórios foram detectados em dentes tratados endodonticamente e implantes dentários. Os erros mais frequentes foram subobturação em dentes tratados endodonticamente, e roscas expostas em implantes dentários.

Acceptable therapeutic protocol in dentistry depends on the outcomes obtained with follow up. Operative procedural errors (OPE) may occur and they represent risk factors able to compromise a tooth or a dental implant. The aim of this study was to detect the OPE in endodontically treated teeth and dental implants, using cone beam computed tomography (CBCT).Eight hundred and sixteen CBCT exams were performed between January 2009 and October 2010, and only those which presented endodontically treated teeth and/or dental implants were selected. The sample was as follows: 195 CBCT exams (n=200 teeth and 200 dental implants), 72 male, 123 female, with mean age of 51 years.In endodontically treated teeth, OPE included underfilling, overfilling, and root perforation; OPEin dental implants were thread exposures, contact with anatomical structures, and contact with adjacent teeth. Kolmogorov-Smirnov test was used for statistical analysis, with significance level set at α=0.05. Underfilling, overfilling, and root perforations were detected in 33.5%, 8% and 4.5% of the teeth, respectively. Dental implants with thread exposures, contact with important anatomical structures and contact with adjacent teeth were seen in 37.5%, 13% and 6.5% of the cases, respectively. OPE were detected in endodontically treated teeth and dental implants, and underfilling and thread exposures were the most frequent occurrences, respectively.

Adequate polymerization plays an important role on the longevity of the composite resin restorations. OBJECTIVES: The aim of this study was to evaluate the effect of light-curing units, curing mode techniques and storage media on sorption, solubility and biaxial flexural strength (BFS) of a composite resin. MATERIAL AND METHODS: Two hundred and forty specimens were made of one composite resin (Esthet-X) in a stainless steel mold (2 mm x 8 mm Ø), and divided into 24 groups (n=10) established according to the 4 study factors: light-curing units: quartz tungsten halogen (QTH) lamp and light-emitting diodes (LED); energy densities: 16 J/cm² and 20 J/cm²; curing modes: conventional (CM) and pulse-delay (PD); and permeants: deionized water and 75% ethanol for 28 days. Sorption and solubility tests were performed according to ISO 4049:2000 specifications. All specimens were then tested for BFS according to ASTM F394-78 specification. Data were analyzed by three-way ANOVA followed by Tukey, Kruskal-Wallis and Mann-Whitney tests (α=0.05). RESULTS: In general, no significant differences were found regarding sorption, solubility or BFS means for the light-curing units and curing modes (p>0.05). Only LED unit using 16 J/cm² and PD using 10 s produced higher sorption and solubility values than QTH. Otherwise, using CM (16 J/cm²), LED produced lower values of BFS than QTH (p<0.05). 75% ethanol permeant produced higher values of sorption and solubility and lower values of BFS than water (p<0.05). CONCLUSION: Ethanol storage media produced more damage on composite resin than water. In general the LED and QTH curing units using 16 and 20 J/cm² by CM and PD curing modes produced no influence on the sorption, solubility or BFS of the tested resin.

O objetivo deste estudo foi avaliar a capacidade de polimerização de três unidades fotopolimerizadoras por meio da análise da influência das fontes de luz, regimes de cura (QTH, L1, L2 e L3) e diferentes permeantes (água e etanol) na sorção, solubilidade e quantidade de monômeros residuais de um adesivo dentário. Espécimes de AdperTM Single Bond 2 foram feitos utilizando uma matriz circular de aço inoxidável (8 mm x 1 mm). Três fontes de luz, uma a base de luz halógena (QTH) e duas a base de diodos emissores de luz (LED), em três diferentes regimes de cura (L1 = 12J; L2 = 24J; L3 = 24J) foram usados para fotoativar os espécimes. Os espécimes foram armazenados em dois tipos de permeantes (água deionizada ou etanol a 75%), por dois diferentes períodos de armazenamento (G1 =7 dias; G2 = 30 dias). Os espécimes foram submetidos a testes de sorção e solubilidade de acordo com a ISO 4049:2000. Após o período de armazenamento, os monômeros residuais foram identificados e quantificados por cromatografia líquida de alta eficiência (HPLC). Para sorção, L1 apresentou os maiores valores significantes e QTH os menores. Para solubilidade, nos grupos do etanol, L1 apresentou os maiores valores e QTH os menores e os achados foram estatisticamente diferentes dos outros regimes de cura. L1 extraiu significantemente mais monômeros do que os outros regimes e QTH teve os menores resultados. As fontes de luz, os regimes de polimerização e os diferentes permeantes influenciaram na sorção, solubilidade e quantidade de monômeros residuais extraídos do adesivo em estudo.

The aim of this study was to assess polymerization ability of three light-curing units by evaluating the influence of the light source, curing regimen and permeant (water or ethanol) on sorption, solubility and amount of residual monomers of a dental adhesive. Specimens of Adper Single Bond 2 were fabricated using a stainless steel circular matrix (8 mm x 1 mm). One quartz-tungsten-halogen (QTH) lamp and two light-emitting diode (LED) device at three different curing regimes (L1 = 12 J; L2 = 24 J; L3 = 24 J) were used to cure the specimens. Specimens were stored in two types of permeants - deionized water or 75% ethanol - for two storage times (G1 =7 days; G2 = 30 days). The specimens underwent water sorption and solubility tests, according to ISO 4049:2000 standard. After storage, residual monomers were identified and quantified by high performance liquid chromatography (HPLC). For sorption, L1 showed the highest values and QTH, the lowest. For solubility, in ethanol-stored groups, L1 had also the highest values, and QTH, the lowest, and findings were significantly different from the other curing regimens. L1 leached significantly more monomers than the others, and QTH had the lowest results. In conclusion, the type of light source, the curing regimen and the permeant affected sorption, solubility and amount of residual monomers of the adhesive under study.

Nexte estudo, avaliou-se os aspectos epidemiológicos das injúrias traumáticas na dentição permanente em uma amostra de 847 pacientes atendidos pelo Serviço de Urgência da Faculdade de Odontologia da Universidade Federal de Goiás, entre os anos de 2000 e 2008. O tratamento estatístico analisou os dados frente à distribuição de freqüência e qui-quadrado. O nível de significância foi de p<0,05. Os resultados mostraram uma maior ocorrência entre os indivíduos do gênero masculino (72,01%), na faixa etária 6-10 anos. A fratura coronária sem exposição do tecido pulpar (502; 26,95%), avulsão (341; 18,30%) e fratura coronária com exposição pulpar (330; 17,71%) constituíram nas injúrias traumáticas mais prevalentes. A prevalência das injúrias traumáticas ao longo dos meses do ano mostrou-se proporcional, sendo observado um maior número de casos entre os meses de julho a setembro (249; 29,39%). afetado foi o incisivo central superior (65,65%), seguido pelo incisivo lateral superior esquerdo (19,67%). Em 311 participantes (18,25%) apenas um dente estava envolvido, enquanto que a maioria dos pacientes (536; 81,75%), injúrias dentárias ocorreram em mais de um dente. Significativa proporção (82,27%) dos dentes traumatizados apresentava os ápices radiculares completamente formados. Os principais fatores etiológicos envolvidos nos traumatismos dentários foram as quedas (51,71%), acidentes automobilísticos (22,90%), e violência (5,67%). Adequadas políticas de prevenção de traumatismos dentários devem ser institucionalizadas, capaz de divulgar protocolos apropriados para o manejo destas lesões. A prevalência de traumatismos dentários em uma subpopulação de Goiânia é comparável a prevalência reportada em estudos epidemiológicos de outras populações.

Epidemiologic aspects of traumatic dental injuries (TDI) were evaluated in the permanent dentition in a sample of 847 patients treated at the Dental Urgency Service of the Dental School of the Federal University of Goiás, Brazil, between May 2000 and May 2008. The statistical treatment analyzed data from frequency distribution and chi-square test. The level of significance was set at 5% for all analyses. The results showed a higher incident among males (610; 72.01%) with mean age of 6-10 year-old. Uncomplicated crown fracture (without pulp exposure) (502; 26.95%), avulsion (341; 18.30%) and complicated crown fracture (with pulp exposure) (330; 17.71%) were the most prevalent TDI. The prevalence of trauma throughout the years showed proportionality, being observed a larger number of cases between July and September (249; 29.39%). The most affected teeth were the maxillary central incisors (65.65%), followed by the maxillary left lateral incisors (19.67%). In 311 participants (18.25%), only one tooth was involved, while in most patients (536; 81.75%), TDI occurred in more than one tooth. Significant proportion (82.27%) of traumatized teeth presented completely formed root apex. The main etiologic factors involved in TDI were falls (51.71%), traffic accidents (22.90%) and violence (5.67%). Based on the obtained data, it may be concluded that accurate policies of TDI prevention must be established, capable of stimulating the exposure of appropriate protocols for management of these lesions. The prevalence of TDI in Goiânia subpopulation is compared to the prevalence reported in epidemiological studies in others populations.

The purpose of this study was to evaluate the sorption and solubility of a composite resin (TPH³; Dentsply) cured with halogen light due to different storage media and curing modes. The methodology was based on the ISO 4049 standard. Two independent groups were established according to the storage time (7 days-G1; 60 days-G2). A stainless steel mould (2 mm x 8 mm Ø) was used. The selected curing modes were: I (Conventional - C): 40s - 600 mW/cm²; II (Pulse I - PD): 3 s - 200 mW/cm² + 2 min (delay) + 39 s - 600 mW/cm²; III (Pulse II): 10 s - 200 mW/cm² + 2 min (delay) + 37 s - 600 mW/cm²; IV (Pulse III): 3 s- 600 mW/cm² + 2 min (delay) + 37 s -600 mW/cm². The media used were: distilled water, 75% ethanol and 100% chlorophorm. Five repetitions were made for each group. The specimens were placed in a desiccator at 37ºC for 24 h and, after that, at 23ºC for 1 h to be weighed until a constant mass (m1) was obtained. The discs were immersed separately into the 3 media for 7 days (G1) and 60 days (G2), and thereafter reweighed (m2). The reconditioning in the desiccator was done until a constant mass (m3) was obtained. Sorption and solubility were calculated and the data of G1 and the sorption data of G2 were subjected to two-way ANOVA and Tukey's tests (p=0.05). The solubility data of G2 were analyzed by Kruskal-Wallis test (p=0.05). For G1 and G2, no statistically significant differences were found in sorption among curing techniques (p>0.05). The solubility values were negative, which means that there was mass gain. Regarding the storage media, in G2 chlorophorm had the highest sorption values. It may be concluded that the curing modes (C and PD I, II and III) did not affect the sorption of the tested composite resin. However, different storage media influenced sorption behavior. The solubility test demonstrated negative data, masking the real solubility.

The aim of this study was to evaluate the polymerization shrinkage and shrinkage stress of composites polymerized with a LED and a quartz tungsten halogen (QTH) light sources. The LED was used in a conventional mode (CM) and the QTH was used in both conventional and pulse-delay modes (PD). The composite resins used were Z100, A110, SureFil and Bisfil 2B (chemical-cured). Composite deformation upon polymerization was measured by the strain gauge method. The shrinkage stress was measured by photoelastic analysis. The polymerization shrinkage data were analyzed statistically using two-way ANOVA and Tukey test (p<0.05), and the stress data were analyzed by one-way ANOVA and Tukey's test (p<0.05). Shrinkage and stress means of Bisfil 2B were statistically significant lower than those of Z100, A110 and SureFil. In general, the PD mode reduced the contraction and the stress values when compared to CM. LED generated the same stress as QTH in conventional mode. Regardless of the activation mode, SureFil produced lower contraction and stress values than the other light-cured resins. Conversely, Z100 and A110 produced the greatest contraction and stress values. As expected, the chemically cured resin generated lower shrinkage and stress than the light-cured resins. In conclusion, The PD mode effectively decreased contraction stress for Z100 and A110. Development of stress in light-cured resins depended on the shrinkage value.

OBJECTIVE: The purpose of this in vitro study was to evaluate the internal adaptation of Class V composite restorations to the cavity walls using three different techniques of polymerization. METHODS: Standard cavities were prepared on the buccal and lingual surfaces of 24 extracted human third molars with margins located above and below the cementoenamel junction. Restorations were placed in one increment using two restorative systems: 3M Filtek A110/ Single Bond (M) and 3M Filtek Z250/ Single Bond (H) in the same tooth, randomly in the buccal and lingual surfaces. Resin composites were polymerized using three techniques: Group 1 - Conventional (60 s - 600 mW/cm²); Group 2 - Soft-start (20 s - 200 mW/cm² , 40 s - 600 mW/cm²); Group 3 - Pulse Activation (3 s - 200 mW/cm², 3-min hiatus, 57 s - 600 mW/cm²). Buccolingual sections were polished, impressions taken and replicated. Specimens were assessed under scanning electron microscopy up to X1000 magnification. Scores were given for presence or absence of gaps (0 - no gap; 1 - gap in one wall; 2 - gap in two walls; 3 - gap in three walls). RESULTS: The mean scores of the groups were (±SD) were: G1M-3.0 (± 0.0); G2M-2.43 (± 0.8); G3M- 1.71 (± 0.9); G1H- 2.14 (± 1.2); G2H- 2.00 (± 0.8); G3H- 1.67 (± 1.1). Data were analyzed using Kruskal-Wallis and Dunnet's tests. No statistically significant difference (p>0.05) was found among groups. Gaps were observed in all groups. CONCLUSIONS: The photocuring technique and the type of resin composite had no influence on the internal adaptation of the material to the cavity walls. A positive effect was observed when the slow polymerization techniques were used.

O objetivo desse estudo foi investigar o efeito do pH de diferentes sistemas adesivos na polimerização de uma resina composta quimicamente ativada (Adaptic - AD), por meio do teste de resistência à tração. Os sistemas adesivos utilizados foram: ARM, Prime & Bond 2.1 (PB), Scotchbond Multi Purpose (SMP) e Single Bond (SB). Cinco grupos (n=5) foram formados: G1: AD/ARM/AD; G2: AD/PB/AD; G3: AD/SMP/AD; G4: AD/SB/AD; G5: AD/AD (sem interposição de adesivo). Uma matriz de aço inoxidável com abertura central no formato de cone (1 mm de espessura; 4 mm de diâmetro), foi utilizada para obter dois discos de resina composta. A resina AD foi inserida em uma primeira metade da matriz em incremento único. Após a polimerização da resina, uma camada de adesivo foi aplicada na superfície de união e foto-ativada. A segunda metade da matriz foi justaposta à primeira e preenchida com a resina. Após 10 min, o conjunto foi adaptado em uma máquina universal de ensaios para determinar a resistência à tração, com velocidade de 0,5 mm/min. Os dados foram submetidos a ANOVA e teste de Tukey (p<0,05). As médias (kgf) obtidas em cada grupo foram: G1: 15,23 ± 4,1; G2: 0,00 ± 0,0; G3: 16,96 ± 2,4; G4: 10,08 ± 2,7; G5: 15,44 ± 0,9. Houve diferença estatisticamente significante (p<0.05) entre os grupos G2-G1; G2-G3; G2-G4; G4-G1; G4-G3. Os sistemas com pHs mais baixos (PB e SB) apresentaram as menores médias de resistência à tração. Os achados desse estudo in vitro sugerem que o pH dos sistemas adesivos influencia na polimerização e na resistência adesiva de materiais resinosos quimicamente ativados. Os sistemas adesivos simplificados testados, com valores de pH mais baixos, mostraram graus distintos de incompatibilidade com a resina quimicamente ativada, quando comparados aos sistemas adesivos convencionais.

The purpose of this study was to investigate the effect of pH of different adhesive systems on the polymerization of a chemically cured composite resin (Adaptic - AD), by means of tensile bond strength testing. The adhesive systems tested were: ARM, Prime & Bond 2.1 (PB), Scotchbond Multi Purpose (SMP) and Single Bond (SB). Bond strength at the resin/adhesive system/resin interface was assessed. Five groups (n=5) were formed, according to following configuration: G1: AD/ARM/AD; G2: AD/PB/AD; G3: AD/SMP/AD; G4: AD/SB/AD; G5: AD/AD (no adhesive). A two-mold stainless steel matrix with a cone-shaped opening (1-mm-thick; 4 mm in diameter) was used to obtain resin discs. AD resin was inserted into the first mold, left-self curing and an adhesive layer was applied onto resin surface and light-cured. The second mold was assembled over the first and was filled with the resin. After 10 min, this setting was loaded in tension in a universal testing machine running at a crosshead speed of 0.5 mm/min. Data were submitted to one-way ANOVA and Tukey's test (p<0.05). Bond strength means (kgf) were: G1: 15.23 ± 4.1; G2: 0.00 ± 0.0; G3: 16.96 ± 2.4; G4: 10.08 ± 2.7; G5: 15.44 ± 0.9. There were statistically significant differences (p<0.05) between G2-G1; G2-G3; G2-G4; G4-G1; G4-G3. The systems with the lowest pHs (PB and SB) yielded the lowest bond strength. The findings of this in vitro study demostrates that the pH of adhesive systems influences the polymerization and bond strength of chemically cured resin materials. The low pH simplified adhesive systems showed distinct degrees of incompatibility with the chemically cured resin, when compared to the conventional adhesive systems.

O objetivo deste estudo foi estudar a influência da fonte de luz, LED e lâmpada halógena (LH), na efetividade de polimerização do cimento resinoso dual Enforce fotoativado sob um disco de porcelana. Três tempos de exposição (60, 80 e 120 segundos) foram também avaliados. Dois grupos experimentais, na qual a polimerização do cimento resinoso foi feita através de um disco cerâmico, e dois controles, polimerização direta do cimento, sem presença do disco cerâmico foram subdivididos em três subgrupos, com cinco amostras em cada: G1A- LH 60s; G1B- LH 80s; G1C- LH 120s; G2A- LED 60s; G2B- LED 80s; G2C- LED 120s; e grupos controles: G3A- LH 60s; G3B- LH 80s; G3C- LH 120s; G4A- LED 60s; G4B- LED 80s e G4C- LED 120s. O cimento resinoso foi inserido em uma matriz de aço (4 mm de diâmetro e 1,2 mm de espessura). Nos grupos experimentais um disco de porcelana (6 mm de diâmetro por 2 mm de espessura) foi colocado sobre o cimento. Este foi fotoativado através da porcelana pela lâmpada halógena e pelo LED, por outro lado nos grupos controles a luz foi aplicada sem o disco de porcelana. As amostras foram armazenadas em um frasco que impedia a passagem de luz a 37(0)C por 24 horas, para que depois a dureza Vickers fosse determinada. Os dados foram submetidos à análise de variância a quatro critérios seguido pelo teste Tukey (p£ 0,05). Todas as amostras polimerizadas pelo LED por 60s mostraram valores inferiores quando comparadas com as do grupo da lâmpada halógena. Em geral, a fotoativação realizada por 80 e 120 s com o LED foi estatisticamente similar à fotoativação com a lâmpada halógena (60 e 80 s). A tecnologia LED pode ser viável para a fotoativação de restaurações indiretas de porcelana quando o tempo de polimerização é aumentado.

The aim of this study was to investigate the influence of light source, LED unit and halogen lamp (HL), on the effectiveness of Enforce dual-cured cement cured under a ceramic disc. Three exposure times (60, 80 and 120 s) were also evaluated. Two experimental groups, in which the polymerization of the dual-cured cement was performed through a ceramic disc, and two control groups, in which the polymerization of the dual-cured cement was performed directly without presence of ceramic disc were subdivided into three subgroups (three different exposure times), with five specimens each: G1A- HL 60s; G1B- HL 80s; G1C- HL 120s; G2A- LED 60s; G2B- LED 80s; G2C- LED 120s; and control groups: G3A- HL 60s; G3B- HL 80s; G3C- HL 120s; G4A- LED 60s; G4B- LED 80s and G4C- LED 120s. Cement was applied in a steel matrix (4mm diameter, 1.2mm thickness). In the experimental groups, a ceramic disc was placed on top. The cement was light-cured through the ceramic by a HL and LED, however, the control groups were cured without the ceramic disc. The specimens were stored in a light-proof container at 37ºC for 24 hours, then Vickers hardness was determined. A four-way ANOVA and Tukey test (p£ 0.05) were performed. All specimens cured by LED for 60s showed inferior values compared with the halogen groups. In general, light-curing by LED for 80s and 120s was comparable to halogen groups (60s and 80s) and their control groups. LED technology can be viable for light-curing through conventional ceramic indirect restorations, when curing time is increased in relation to HL curing time.

Uma grande variedade de produtos odontológicos que são lançados no mercado faz da seleção do material uma difícil tarefa. Apesar das propriedades mecânicas não representarem necessariamente o seu real desempenho clínico, os testes são utilizados para orientar os efeitos das alterações das composições do material ou a evolução das suas propriedades. Além disso, estas propriedades podem ajudar o clínico de alguma forma na seleção correta, uma vez que a comparação entre as formulações anteriores e as mais recentes, assim como as líderes de mercado são mais destacadas pelos fabricantes. Este artigo apresenta uma revisão dos testes laboratoriais mais importantes. Desta forma, o conhecimento destes ensaios fornecerá uma opinião crítica relacionada às propriedades dos diferentes materiais dentários.

A wide variety of dental products that are launched on the market becomes the correct selection of these materials a difficult task. Although the mechanical properties do not necessarily represent their actual clinical performance, they are used to guide the effects of changes in their composition or processing on these properties. Also, these tests might help somehow the clinician to choose once comparisons between former formulations and new ones, as well as, with the leading brand, are highlighted by manufactures. This paper presents a review of the most important laboratory tests. In this manner, the knowledge of these tests will provide a critical opinion related to the properties of different dental materials.