Impact of Calcium-Hydroxide, Sodium Ascorbate, and Sodium Thiosulphate on Bond Strength of Composite Restorations to Bleached Dentin.

This study evaluated the impact of using calcium-hydroxide or the antioxidant agents on the bond strength of adhesive restorations to bleached dentin. Forty teeth were prepared and allocated into 8 groups according to the surface treatment after bleaching (application or not of calcium hydroxide, 10% sodium ascorbate and 5% sodium thiosulphate for 10min), and the time of final restoration (immediate or after 7-days). Sodium perborate with 20% hydrogen peroxide was applied for 3 weeks using a developed artificial pulp chamber, with replacement every week. Composite resin restoration was performed and microtensile test was performed. Then, specimens were analyzed using a stereomicroscope and SEM. Data was submitted to Kruskal-Wallis and Dunn tests (p<0.05). The bond strength of non-bleached teeth was similar to the groups restored after 7 days of bleaching (p<0.05). The lowest values of bond strength were showed by groups restored immediately after bleaching (p<0.05). In all groups, there was a considerable predominance of adhesive fractures. Delaying the final restoration of teeth submitted to nonvital bleaching for 7 days permits an increase in bond strength. The immediate restoration of bleached teeth after the use of 10% sodium ascorbate or 5% sodium thiosulfate for 10 minutes showed unsatisfactory results. Clinical relevance Irrespective of the dentin protocol applied before adhesion, a satisfactory and an unsatisfactory result of bond strength values will be obtained delaying the final restoration or immediately performing the final restoration, respectively. Therefore, after nonvital tooth bleaching, clinicians should always delay the final restoration for a minimum period of 7 days.

Satisfaction Survey of Patients Using the Brazilian Version of Dental Patient Feedback on Consultation Questionnaire / Pesquisa de Satisfação de Pacientes Utilizando a Versão Brasileira do Questionário Dental Patient Feedback on Consultation skills

The aim of this study was to measure the satisfaction of patients treated in a dental hospital using a validated questionnaire on patient-dentist communication and investigate factors associated with satisfaction. Patients in the dental clinic answered 2 questionnaires: Dental Patient Feedback on Consultation (DPFC) and another regarding their oral health perceptions using a visual analog scale (VAS) and sociodemographic backgrounds. The correlation between patient's satisfaction and other numerical variables was determined using Spearman's test. The KruskalWallis and Mann-Whitney tests were used to compare the patient's satisfaction scores and the categories of the independent variables (p≤0.05). The median DPFC score was 2.9. All participants were very satisfied considering the active dentist listening (Q3) and the dental treatment advices (Q16). The lowest score was observed about family habits and medical history in oral health (Q9:2.0). With respect to their oral health perceptions, the majority of the participants demonstrated satisfaction with their chewing, smile and dental aesthetics. Being younger than 40 years influenced the satisfaction with oral health satisfaction when the VAS score was analyzed. The skin colour (p=0.001 and p=0.005) and the marital status (p=0.001 and p=0.006) of the participants also demonstrated a statistically positive signiticant correlation between DPFC and VAS scores, respectively. There was a high level of patient's satisfaction with the ability of the dentist to communicate in the dental hospital analyzed. Age, color skin, and the marital status of patients interfered in the satisfaction about patient-dentist communication and their oral health perception.(AU)

O objetivo deste estudo foi mensurar a safisfação de pacientes tratados em um hospital utilizando um questionário validado baseado na comunicação dentista-paciente e investigar os fatores associados a esta satisfação. Os pacientes da clínica responderam 2 questionários: Dental Patient Feedback on Consultation (DPFC) e outro a respeito das percepções relacionadas a saúde utilizando uma Escala Visual Analógica (EVA) e dados sociodemográficos. A correlação entre a satisfação dos pacientes e outras variáveis numéricas foi determinada através do teste de Spearman. Os testes de Kruskal-Wallis e Mann-Whitney foram usados para os escores de satisfação dos pacientes e as variáveis categóricas independents (p≤0,05). O escore mediano do DPFC foi de 2,9. Todos os participantes estavam muito satisfeitos considerando a escuta ativa do dentista (Q3) e as recomendações sobre o tratamento dentário (Q16). O escore mais baixo foi relacionado aos hábitos familiares e história médica relacionada a saúde bucal (Q9:2.0). Em relação as percepções a saúde bucal, a maioria dos participantes demonstrou satisfação com a mastigação, sorrisco e estética dental. Ter menos de 40 anos influenciou a satisfação com a saúde bucal quando a escala EVA foi utilizada. A cor da pele (p=0,001 e p=0,005) e a relação conjugal (p=0,001 e p=0,006) também demonstraram uma significância estatística positiva entre o DPFC e a escala EVA, respectivamente. Foi observado um alto nível de satisfação dos pacientes em relação a habilidade de comunicação do dentista no hospital analisado. Idade, cor da pele e a relação conjugal dos pacientes interferiu na satisfação relacionada a comunicação do dentista-paciente e a percepção de saúde bucal.(AU)

Influence of age and experience with magnification on locating the second mesiobuccal canal in maxillary first molars: A preliminary study.

The aim was to evaluate the effectiveness of clinical methods in identifying the presence of second mesiobuccal canal in maxillary first molars. The influence of age and experience with microscopy was also assessed. Sixty six teeth were selected and the mesiobuccal canal was confirmed in all of the samples by Cone-Beam Computed Tomography. After endodontic cavity access, teeth were evaluated through direct visual; dental loupe and operating microscope. None of the methods was successful in finding the mesiobuccal canal in all samples. Professionals <40, the magnification did not influence the location. Professionals >40, the magnification significantly influenced the location. In the direct vision, professionals >40 years located fewer canals than those <40 years of age with experience. In conclusion, these preliminary findings showed that when the microscope was used, the professionals with experience, regardless of age, found a higher number of canals. The use of the microscope was significant for professionals >40 years.

Is YouTubeTM a reliable source of information regarding ultra-thin ceramic laminates?

An aesthetic smile is usually associated with healthy appearance and success in many areas of life. Currently, individuals access the internet and social media in search of health information. The aim of this study was to analyse the quality and reliability of information in videos available on the YouTubeTM platform about ultra-thin ceramic laminates. Methods: YouTubeTM was searched using the therms "dental ceramic laminates" and "dental contact lens" for videos uploaded on ultra-thin ceramic laminates. The first 100 videos in Portuguese were selected and rated for quality and reliability. The content and source of videos were also noted. The quality of the videos was determined by evaluating the presence or absence of reliable information and distributed into seven domains. To compare the distributions of quantitative variables between the classifications of source, content, and quality, the Kruskal-Wallis and Dunn's post-hoc tests were performed. Results: Seventy-two videos were included for qualitative analysis. Regarding quality rating, most videos were rated with poor quality. The reliability of the evaluated videos was low. Conclusion: YouTubeTM showed a large number of videos with many views on the topic, but it does not contribute with good quality and reliable information to the population

Effects of Two In-Office Bleaching Agents with Different Compositions on the Bond Strength to Enamel.

This study evaluates the effect of two in-office bleaching agents with different compositions on the bond strength to enamel surface. Fifty bovine teeth were divided into five groups (n = 10 teeth per group), according to the bleaching agent used and the time elapsed to perform the restorative procedures: restorative procedures performed without bleaching (control group); bleaching with 35% hydrogen peroxide (HP), with restorative procedures 24 hours or 7 days after bleaching (HP/24h and HP/7d groups, respectively); and bleaching with 35% HP with calcium compost, with restorative procedures 24 hours or 7 days after bleaching (HP AutoMixx/24h and HP AutoMixx/7d groups, respectively). The specimens were stored at 37°C in artificial saliva. Restored teeth were submitted to a micro-shear bond strength test. The specimens were analyzed using a stereoscope to determine the fracture pattern, classified as adhesive, cohesive, or mixed. The results of the bond strength test were evaluated by analysis of variance, with significance set at P < .05. The groups showed similar bond strength values without significant difference among them (P > .05). There was a predominance of the adhesive-type fracture pattern in all groups. The bleaching agents with different compositions showed similar bond strength values when the restoration was performed 24 hours and 7 days after bleaching, and the results were similar to the control group.

Do non-clinical subjective factors influence the treatment decisionmaking of Brazilian dentists?

The literature contains little information on several non-clinical factors such as the association between graduate residency programs and the application of minimally invasive dentistry, or on dentists' clinical decision-making processes for replacing restorations for esthetic reasons. This study evaluated whether non-clinical subjective factors influence the treatment decisions made by Brazilian dentists regarding technical and esthetic matters. Dentists were invited to participate in a cross-sectional survey by answering an electronic questionnaire containing clinical cases, regarding what treatment they would select for: T1 - a molar tooth with significant crown destruction and spontaneous pain, and T2 - premolar teeth with extensive amalgam restorations and no carious lesion or associated complaint. The survey also included questions about subjective variants (sociodemographic and professional). Chi Square test and Fischer's Exact test were used toanalyzetheanswers to T1, and one-factor analysis of variance and post-hoc Tamhane were applied to T2. The significance level was set at 5% for all analyses. A total 302 professionals participated in the study. For T1, it was found that clinical decision-making was influenced by the Brazilian region of clinical practice (p=0.005). For T2, a significant association was found between increased loss of patient tooth tissues and whether the professional had completed a residency program in Operative Dentistry (p=0.035), worked in a private practice (p=0.033), or if most of his/her patients belonged to a high estimated socioeconomic level (household income above $4350) (p=0.002). In conclusion, the clinical decision-making of Brazilian dentists varies according to professional profile, mainly with relation to the replacement of restorations due to esthetic concerns.

Vários fatores não clínicos, como a associação entre programas de especialização e a aplicação da odontologia minimamente invasiva, ainda são escassos na literatura. Outro aspecto relevante é a tomada de decisão clínica do dentista quanto à substituição de restaurações em função da aparência estética. Este estudo avaliou se fatores subjetivos não clínicos influenciam na tomada de decisão clínica de dentistas brasileiros com base em questões técnicas e estéticas. Foi realizado um estudo transversal com um questionário eletrônico contendo casos clínicos que foram apresentados a uma lista de profissionais. No questionário, interrogou-se o tratamento proposto para um dente molar com destruição coronária significativa e dor espontânea (T1). Também foi questionado o tratamento proposto para dentes prémolares com extensas restaurações de amálgama e sem lesão cariosa ou queixas associadas (T2). Em seguida, foram questionadas as variantessubjetivas(sociodemográfica eprofissional). Na análise de T1, foram utilizados os testes Qui Quadrado e Exato de Fischer. Em T2, foi aplicada a análise de variância de um fator e post-hoc Tamhane. Para todas as análises, o nível de significância foi estabelecido em 5%. Um total de 302 profissionais participaram deste estudo. A tomada de decisão clínica para T1 foi influenciada pela região brasileira de prática clínica (p = 0,005). Em T2, realizar especialização em Dentística Operatória (p = 0,035), trabalhar em consultório particular (p = 0,033) e a maioria dos pacientes apresentar nível socioeconômico estimado elevado (renda familiar acima de R$10.000,00) (p = 0,002) aumentou significativamente a perda de tecidos dentários. Em conclusão, a tomada de decisão clínica dos dentistas brasileiros varia de acordo com o perfil dos profissionais, principalmente no que se refere à substituição de restaurações por questões estéticas.

Do non-clinical subjective factors influence the treatment decisionmaking of Brazilian dentists? / Fatores subjetivos não clínicos influenciam na tomada de decisão do tratamento de cirurgiões-dentistas brasileiros?

ABSTRACT The literature contains little information on several non-clinical factors such as the association between graduate residency programs and the application of minimally invasive dentistry, or on dentists' clinical decision-making processes for replacing restorations for esthetic reasons. This study evaluated whether non-clinical subjective factors influence the treatment decisions made by Brazilian dentists regarding technical and esthetic matters. Dentists were invited to participate in a cross-sectional survey by answering an electronic questionnaire containing clinical cases, regarding what treatment they would select for: T1 - a molar tooth with significant crown destruction and spontaneous pain, and T2 - premolar teeth with extensive amalgam restorations and no carious lesion or associated complaint. The survey also included questions about subjective variants (sociodemographic and professional). Chi Square test and Fischer's Exact test were used to analyze the answers to T1, and one-factor analysis of variance and post-hoc Tamhane were applied to T2. The significance level was set at 5% for all analyses. A total 302 professionals participated in the study. For T1, it was found that clinical decision-making was influenced by the Brazilian region of clinical practice (p=0.005). For T2, a significant association was found between increased loss of patient tooth tissues and whether the professional had completed a residency program in Operative Dentistry (p=0.035), worked in a private practice (p=0.033), or if most of his/her patients belonged to a high estimated socioeconomic level (household income above $4350) (p=0.002). In conclusion, the clinical decision-making of Brazilian dentists varies according to professional profile, mainly with relation to the replacement of restorations due to esthetic concerns.

RESUMO Vários fatores não clínicos, como a associação entre programas de especialização e a aplicação da odontologia minimamente invasiva, ainda são escassos na literatura. Outro aspecto relevante é a tomada de decisão clínica do dentista quanto à substituição de restaurações em função da aparência estética. Este estudo avaliou se fatores subjetivos não clínicos influenciam na tomada de decisão clínica de dentistas brasileiros com base em questões técnicas e estéticas. Foi realizado um estudo transversal com um questionário eletrônico contendo casos clínicos que foram apresentados a uma lista de profissionais. No questionário, interrogou-se o tratamento proposto para um dente molar com destruição coronária significativa e dor espontânea (T1). Também foi questionado o tratamento proposto para dentes prémolares com extensas restaurações de amálgama e sem lesão cariosa ou queixas associadas (T2). Em seguida, foram questionadas as variantes subjetivas (sociodemográfica e profissional). Na análise de T1, foram utilizados os testes Qui Quadrado e Exato de Fischer. Em T2, foi aplicada a análise de variância de um fator e post-hoc Tamhane. Para todas as análises, o nível de significância foi estabelecido em 5%. Um total de 302 profissionais participaram deste estudo. A tomada de decisão clínica para T1 foi influenciada pela região brasileira de prática clínica (p = 0,005). Em T2, realizar especialização em Dentística Operatória (p = 0,035), trabalhar em consultório particular (p = 0,033) e a maioria dos pacientes apresentar nível socioeconômico estimado elevado (renda familiar acima de R$10.000,00) (p = 0,002) aumentou significativamente a perda de tecidos dentários. Em conclusão, a tomada de decisão clínica dos dentistas brasileiros varia de acordo com o perfil dos profissionais, principalmente no que se refere à substituição de restaurações por questões estéticas.

Age and experience with dental operating microscope: Do these factors influence on the post space preparation and adhesion of glass fiber posts?

This study evaluated the influence of operator's age and experience with dental operating microscope (DOM) on the cleaning of post space walls and on bond strength of glass fiber posts associated with self-adhesive resin cement. Sixty bovine roots were selected. Root canal preparation was performed and roots were filled using gutta-percha/AH Plus. For post space preparation, specimens were divided into four groups (n = 15), according to operator's age and the use of DOM: (1) ≥40 years; (2) ≥40 years with magnification; (3) <40 years; (4) <40 years with magnification. Next, a high-speed bur of the post system and torque-controlled round burs were used for cleaning of post space. Five roots in each group were evaluated for the degree of cleanliness under a stereo microscope using a scoring system. In the remaining 10 specimens from each group, glass fiber posts were cemented with RelyX U200. Two slices (1 ± 0.1 mm) prepared on each root third of all specimens were evaluated by push-out analysis. The scoring system was analyzed using Kruskal-Wallis and push-out data using ANOVA. Significance level was set at 5%. No significant difference was observed in cleaning scores among groups (p > .05). There was no significant difference when comparing the groups and the root thirds (p > .05). The adhesive failure between dentin, cement, and post predominated in all groups. Operator's age and experience with DOM did not influence the cleanliness of root canal walls or the bond strength of glass fiber posts associated with self-adhesive resin cement for post space preparation. RESEARCH HIGHLIGHTS: Although magnification is considered part of Endodontics, little is known about the variables associated. Operator's age and experience with microscope on cleaning of canals and on push-out of posts with self-adhesive resin cement were evaluated.

Molhabilidade de um cimento endodôntico à base de resina epóxi na dentina tratada com diferentes protocolos de quelação / Wettability of an epoxy resin-based root canal sealer on dentin treated with different chelating protocols

Objetivo: Avaliar a molhabilidade do cimento AH Plus em contato com a dentina radicular após diferentes protocolos quelantes envolvendo ácido etidrônico (HEBP) e o EDTA. Métodos: Cinquenta e seis fatias de dentina radicular foram utilizadas e irrigadas com 5.25% de hipoclorito de sódio (NaOCl) ou com uma mistura de 5.25%NaOCl/18%HEBP para simular a irrigação durante o preparo químico-mecânico. As amostras irrigadas com NaOCl foram divididas em 5 grupos, de acordo com o agente quelante: G1- água destilada (AD); G2-17%EDTA; G3-17%EDTA+2.5%NaOCl; G4-18%HEBP; e G5-18%HEBP+2.5%NaOCl. As amostras irrigadas com a mistura de NaOCl/HEBP foram dividias em 2 grupos: G6-AD; G7-NaOCl/HEBP+2.5%- NaOCl. Todos os protocolos receberam irrigação de AD entre as substâncias irrigadoras e como lavagem final. O goniômetro Rame-Hart foi utilizado para mesurar o ângulo de contato entre a superfície da dentina radicular e o cimento. O teste estatístico Kruskal-Wallis e Dunn foram aplicados (p<0.05). Resultados: Os grupos onde a smear layer foi removida apresentaram menor ângulo de contato (p<0.05), com exceção do G7. O G6 apresentou o menor ângulo de contato do AH Plus, entretanto, a irrigação final com NaOCl (G7) aumentou significativamente o ângulo de contato. G2 e G4 apresentaram comportamento similar e a irrigação final com NaOCL (G3 e G4) não modificou a molhabilidade da dentina. Conclusão: O tratamento da dentina radicular com a mistura NaOCl/HEBP, quando usada como irrigante, conferiu boa molhabilidade desta superfície ao cimento AH Plus(AU).

Evaluate the wettability of AH Plus in contact with root dentin after different chelating protocols involving etidronic acid (HEBP) and EDTA. Material and Methods: Fifty six human polished root dentin slices were used. They were irrigated with 5.25% sodium hypochlorite (NaOCl) or a mixture of 5.25%NaOCl/18%HEBP to simulate irrigation during chemomechanical preparation. The specimens irrigated with NaOCl were divided into 5 groups regarding chelating agents: G1-destiled water (DW); G2- 17%EDTA; G3-17%EDTA+2.5%NaOCl; G4-18%HEBP; and G5-18%HEBP+2.5%NaOCl. The specimens irrigated with the mixture NaOCl/HEBP were divided into 2 groups: G6-DW; G7-NaOCl/HEBP+2.5%NaOCl. All protocols received irrigation with DW between irrigants and as final rinse. Rame-Hart goniometer was used to measure the contact angle between the dentin surfaces and the sealer. Kruskal-Wallis and Dunn tests were applied (p<0.05). Results: Groups in which the smear layer was removed showed a lower contact angle (p<0.05), except for G7. The G6 showed the lowest contact angle of AH Plus, but the NaOCl final irrigation (G7) increased the angle. G2 and G4 have similar behaviour and final irrigation with NaOCl (G3 and G5) did not change wettability when these chelators were used. Conclusions: The mixture NaOCl/HEBP showed good effect on the wettability of sealer on to the root canal dentine, when used as main irrigant (AU).

Photobiomodulation therapy for oral mucositis management in head and neck cancer patients undergoing radiotherapy: case reports

Introduction: Photobiomodulation therapy (PBM) has been recommended for the prevention of oral mucositis (OM). Objective: to evaluate the use of PBM to prevent and control the severity of oral mucositis lesions and painful sensitivity in patients undergoing radiotherapy for head and neck cancer (HNC) treatment. Case reports: Eight patients with HNC attended for radiotherapy treatment, either associated with chemotherapy, or not were followed up. Clinical evaluation was performed, including meticulous anamnesis. The patients were followed up throughout the entire period of radiotherapy treatment. For the protocol of prophylaxis of OM, low level laser equipment was used, with a wavelength in the range of 660nm, in a contact mode, 30 mW of continuous emission 4J/cm² three times per week and for the therapeutic protocol wavelength in the range of 660nm, in a contact mode, 30 mW of continuous emission 8 J/cm², in the respective areas compromised by oral mucositis, 3 times per week till the complete remission of the lesions. All the patients were clinically followed up from the beginning of the antineoplastic therapy up to the conclusion of the medical treatment or total remission of the oral lesion, involving post radiotherapy control. A visual analog scale (VAS) was used to measure pain every week. Results: A progressive development of the lesions was observed from the 1st to the 5th week. Remission of OM was observed from the 7th week up to the conclusion of treatment. There is a continuous increase in the pain process, attaining the maximum level in the 6th week, with decline occurring up to the 7th week. Conclusion: Photobiomodulation therapy was able to control the severity of OM lesions and painful sensitivity in patients undergoing radiotherapy for head and neck cancer treatment, avoiding the interruption of the cancer therapy.

Introdução: A terapia com fotobiomodulação (FBM) tem sido recomendada para a prevenção da mucosite oral (MO). Objetivo: avaliar o uso de FBM para prevenir e controlar a gravidade das lesões da mucosite oral e a sensibilidade dolorosa em pacientes submetidos à radioterapia para tratamento de câncer de cabeça e pescoço (CCP). Relato dos casos: Oito pacientes com CCP atendidos para tratamento radioterápico, associado ou não à quimioterapia, foram acompanhados. Foi realizada avaliação clínica, incluindo anamnese meticulosa. Os pacientes foram acompanhados durante todo o período de tratamento radioterápico. Para o protocolo de profilaxia de MO, foi utilizado um equipamento laser de baixa potência, com comprimento de onda na faixa de 660nm, em modo de contato e 30 mW de emissão contínua com 4J/cm2. Para o protocolo terapêutico, e para comprimento de onda na faixa de 660nm, em modo de contato e 30 mW de emissão contínua com 8J/cm2 na área da lesão, até sua completa remissão. Todos os pacientes foram acompanhados clinicamente desde o início da terapia antineoplásica até a conclusão do tratamento médico ou remissão total da lesão oral, envolvendo o controle pós-radioterapia. Uma escala visual analógica (EVA) foi usada para medir a dor semanalmente. Resultados: Observou-se um desenvolvimento progressivo das lesões da 1ª à 5ª semana. A remissão da mucosite oral foi observada a partir da 7ª semana até o final do tratamento. Houve um aumento contínuo do processo doloroso, atingindo o nível máximo na 6ª semana, com declínio ocorrendo até a 7ª semana. Conclusão: A terapia de fotobiomodulação foi capaz de controlar a gravidade das lesões de MO e a sensibilidade dolorosa em pacientes submetidos à radioterapia para tratamento do câncer de cabeça e pescoço, evitando a interrupção da terapia oncológica.

A second attempt at pulp revascularisation on an immature traumatised anterior tooth: a case report with two-year follow-up.

This report describes the second attempt at pulp revascularisation, using an association between 2% chlorhexidine (CHX) and calcium hydroxide (CH) as intracanal dressing, in an immature traumatised anterior tooth with pulp necrosis. A 21-year-old woman complained of pain and dental crown darkening of a permanent maxillary right central incisor. Her medical records presented a history of dental trauma, and at age 15, the first attempt at revascularisation was performed, using triple antibiotic paste (TAP) as the intracanal dressing. Recent radiographs then showed a periapical lesion associated with an immature root, which demonstrated the failure of the first attempt. The second pulp revascularisation was performed, using an association between CHX and CH as intracanal medication. The case was followed up for 24 months. Observations showed evidence of root development, dentinal wall thickening and periapical healing. In this case, the association between CHX and CH showed favourable results as an intracanal medication.

Avaliação das características superficiais dos instrumentos Reciproc, Reciproc Blue e Xp-Endo Shaper / Evaluation of the surface characteristics of the Reciproc, Reciproc Blue and Xp-Endo Shaper instruments

Introdução: o controle da qualidade no processo de fabricação dos instrumentos endodônticos é importante uma vez que defeitos e falhas superficiais podem comprometer o preparo dos canais. Objetivo: avaliar a presença de defeitos e falhas do processo de fabricação na superfície de instrumentos Reciproc (R25), Reciproc Blue (RB25) e XP-endo shaper (XP), por meio de microscopia eletrônica de varredura (MEV). Materiais e Métodos: Ao total, foram avaliados 60 instrumentos de níquel titânio, sendo 20 por grupo: R25, RB25 e XP, em três regiões: 0mm (ponta do instrumento), 4mm e 7mm da ponta, no MEV, com aumento de 100x. As imagens foram avaliadas quanto ao número de falhas de fabricação (bordo irregular, ranhura, microcavidade e rebarba) e por um sistema de escores de 1 a 4, sendo 1, nenhuma área com defeito e 4, mais de cinco áreas com defeitos na superfície. Os dados foram submetidos à análise estatística utilizando o teste de Dunn (p<0,05). Resultados: Sobre a análise por regiões, foram identificadas diferenças significativas em grande parte dos instrumentos. Comparando os diferentes instrumentos, não foi observada diferença significativa para microcavidade (p=0,76), bordo irregular (p=0,98) e rebarba (p=0,40). O instrumento R25 mostrou maior número de ranhuras em comparação aos demais (p=0,0000*). RB25 mostrou maiores valores de escores que os instrumentos R25 (p= 0,0002) eXP (p=0,01). Conclusão: Todos os instrumentos avaliados apresentaram defeitos/falhas superficiais do processo de fabricação.

Introduction: The quality control of endodontic instruments is extremely importantsince defects and failures on their surface, during their manufacturing process, can compromise the preparation of root canal. Objective: this study evaluated the presence of defects and failures in the manufacturing process on the surface of Reciproc (R25), Reciproc Blue (RB25) and XP endo-shaper (XP) instruments by means of scanning electron microscopy (SEM). Materials and Methods: In total, sixty nickel titanium instruments (n=20): R25, RB25 and XP were evaluated in the scanning electron microscope in three regions: 0mm (tip of the instrument), 4mmand 7mm of the tip, with a magnification of 100x. The images were evaluated in relation to the number of manufacturing faults (irregular border, groove, microcavity and burr) and by a system of scores, from 1 to 4, where 1 is no defective area and 4, more than five areas with defects on the surface. The data were submitted to statistical analysis using Kruskal-Wallis and Mann-Whitney tests (p<0.05). Results: Regarding the analysis by regions, significant differences were identified in most of the instruments. Comparing the different instruments, no significant difference was observed for microcavity (p=0.76), irregular border (p=0.98) and burr (p=0.40). The R25 instrument showed a greater number of grooves compared to the others (p=0.0000*). RB25 showed higher scores than the R25(p=0.0002) and XP (p=0.01) instruments. Conclusion: All evaluated instruments showed defects/failures in the manufacturing process.Introduction: The quality control of endodontic instruments is extremely importantsince defects and failures on their surface, during their manufacturing process, can compromise the preparation of root canal. Objective: this study evaluated the presence of defects and failures in the manufacturing process on the surface of Reciproc (R25), Reciproc Blue (RB25) and XP endo-shaper (XP) instruments by means of scanning electron microscopy (SEM). Materials and Methods: In total, sixty nickel titanium instruments (n=20): R25, RB25 and XP were evaluated in the scanning electron microscope in three regions: 0mm (tip of the instrument), 4mmand 7mm of the tip, with a magnification of 100x. The images were evaluated in relation to the number of manufacturing faults (irregular border, groove, microcavity and burr) and by a system of scores, from 1 to 4, where 1 is no defective area and 4, more than five areas with defects on the surface. The data were submitted to statistical analysis using Kruskal-Wallis and Mann-Whitney tests (p<0.05). Results: Regarding the analysis by regions, significant differences were identified in most of the instruments. Comparing the different instruments, no significant difference was observed for microcavity (p=0.76), irregular border (p=0.98) and burr (p=0.40). The R25 instrument showed a greater number of grooves compared to the others (p=0.0000*). RB25 showed higher scores than the R25(p=0.0002) and XP (p=0.01) instruments. Conclusion: All evaluated instruments showed defects/failures in the manufacturing process.

Corn starch films as a long-term drug delivery system for chlorhexidine gluconate.

The present study describes the development of a chlorhexidine long-term drug delivery system using starch as a biodegradable polymer base. Three batches of thermoplastic starch films, containing starch particles/nanoparticles and chlorhexidine (CHX), were manufactured by casting. Morphological characterization showed an irregular surface with particles incorporated with chlorhexidine agglomerated in a starch matrix. Nanoindentation showed that the control film (without chlorhexidine) presented a more plastic and rigid behavior in relation to the films containing CHX. CHX was partially bounded to starch and prevented starch crystallization. Starch nanoparticles formed by precipitation were observed through transmission electron microscopy. By incorporating CHX into the solution, the nanoparticles presented different morphology, suggesting absorption of the drug. In vitro drug release was observed for 21 days by UV-vis spectrophotometry and released CHX amounted up to 19 mg/100 ml. Films presented microbiological potential for inhibiting Staphylococcus aureus growth as evaluated by the disk diffusion test in agar. It has been concluded that the developed film met the main requirements for a drug delivery system and that it is possible to be produced from a simple, cheap and reproduceable process.

Análise da morfologia dos canais radiculares de pré-molares inferiores por meio da tomografia computadorizada de feixe cônico / Analysis of the root canal morphology of mandibular premolars using cone-beam computed tomography

O sucesso do tratamento endodôntico de- pende da limpeza e da modelagem dos canais radiculares. Para tanto, deve-se ter um conhecimento profundo sobre a anatomia do sistema de canais radiculares. No entanto, essa anatomia é complexa, com variações mor- fológicas em diferentes populações. Objetivo: O objetivo desse trabalho foi avaliar, em imagens de tomografia computadorizada de feixe cônico (TCFC), a anatomia dos canais radiculares de pré-molares (PM) inferiores de uma população brasileira. Métodos: Foram analisados 426 pré-molares inferiores nos cortes axiais, coronais e sagitais de TCFC. O número de raízes, canais radiculares e a classificação de Vertucci foram tabulados no programa Microsoft Excel. Associações entre o sexo, número de raízes e canais, e classificação de Vertucci foram avaliadas por meio do teste qui-quadrado (p<0,05). Resultados: dos 426 dentes avaliados, 224 (52,6%) foram 1oPM e 202 (47,4%), 2o PM. Os 1oPM apresentaram, em sua maioria, uma raiz (93,3%) e todos os 2oPM, apenas uma raiz. Nos dentes estudados, verificou-se classificação tipos I, II e V de Vertucci, sendo o tipo I o mais encontrado. O tipo V só esteve presente nos 1oPM com duas raízes (p<0,001). Não houve associação significativa entre o número de raízes e o sexo (p=0,182). Conclusão: A maioria dos pré-molares inferiores apresentou uma raiz com classificação tipo I de Vertucci, demonstrando uma baixa variação anatômica nos PM inferiores da população estudada. Não houve predileção por sexo, quanto ao número de raízes e à classificação do tipo de canal radicular.

Introduction: The success of an endodontic treatment depends primarily on cleaning and shaping of the root canal system. Therefore, the anatomy of the root canal system should be known in detail. However, this anatomy is complex and varies morphologically in different populations. This study evaluated the root canal anatomy of mandibular premolars in a Brazilian population using cone beam CT (CBCT). Methods: CBCT axial, coronal and sagittal slices of 426 mandibular premolars were analyzed. Number of roots and canals, as well as Vertucci type, were recorded using a spreadsheet. Associations between sex, number of roots, and Vertucci type were analyzed using a chi-square test (p<0.05). Results: Of the 426 teeth evaluated, 224 (52.6%) were first premolars and 202 (47.4%), second premolars. Most first premolars (93.3%) and all second premolars had one root. Vertucci types I, II and V were found, and type I was the most frequent. Type V was only found in two-rooted first premolars (p<0.001). There were no significant associations between number of root and sex (p=0.182). Conclusion: Most mandibular premolars had one root and were Vertucci type I, which indicates that there is little anatomic variation of these teeth in the Brazilian population under study. There was no sex predilection for number of roots or Vertucci type (AU).

Avaliação do tratamento endodôntico em sessão única e retratamento não cirúrgico com alargamento foraminal de dentes com periodontite apical / Evaluation of single visit endodontic treatment and non-surgical retreatment with foraminal enlargment of teeth with apical periodontitis ?

Objective: to evaluate the root canal treatment (RCT) and non-surgical root canal retreatment (NSRCR), associated with foraminal enlargement, performed on a singlevisit. Material and Methods: 125 teeth with apical periodontitis and follow-up period ranging from 6 to 12 months were included. The success was considered by the absence of signs and symptoms and complete or incomplete periapical repair. Logistic regression analyses were used to identify factors associated with the repair (p<0.05). Results: RCT showed 71.58% of complete healing and 23.16% of acceptable healing. NSRCR showed 80% of complete healing and 20% of acceptable healing. Age, gender, type of treatment and preoperative pain were not statistically significant for the healing process (p>0.05). Premolars showed the greatest chance of periapical repair. Pulp Canal Sealer showed a greater chance of periapical repair when compared to Sealapex (p<0.05). Conclusion: RCT and NSRCR using a foraminal enlargement protocol provided a favorable prognosis of periapical healing

Objetivo: avaliar o tratamento endodôntico (TE) e o retratamento não cirúrgico do canal radicular (RNCCR), associado a ampliação foraminal, realizado em sessão única. Material e Métodos: foram incluídos 125 dentes com periodontite apical e proservação de 6 a 12 meses. O sucesso foi considerado pela ausência de sinais e sintomas e reparo periapical completo ou incompleto. Análises de regressão logística foram utilizadas para identificar fatores associados ao reparo (p<0,05). Resultados: o TE mostrou 71,58% de cicatrização completa e 23,16% de cicatrização aceitável. O RNCCR mostrou 80% e 20% cicatrização completa e aceitável, respectivamente. Idade, sexo, tipo de tratamento e dor pré-operatória não foram estatisticamente significantes para o processo de cicatrização (p>0,05). Os pré-molares apresentaram a maior chance de reparo periapical. O cimento Pulp Canal Sealer mostrou maior chance de reparo periapical quando comparado ao Sealapex (p<0,05). Conclusão: o TE e RNCCR utilizando um protocolo de alargamento foraminal, proporcionaram um prognóstico favorável da cicatrização periapical

Micro-computed tomographic evaluation of smear layer and accumulated hard tissue debris removal.

BACKGROUND: The isthmus and irregularities present in the root canal system are potential areas for debris accumulation areas and therefore the seach for devices and solutions to improve cleaning of these areas is of utmust importance. This study evaluated, by micro-computed tomography, the efficiency of 37% phosphoric acid solution with that of 17% EDTA in the removal of smear layer and accumulated hard tissue debris (AHTD) after canal preparation. METHODS AND MATERIALS: Twenty-six mesial roots of mandibular molars were subjected to microtomographic scanning using the SkyScan 1173 X-ray microtomograph at a resolution of 14,97 µm. The canals were prepared using Reciproc R40 instruments, 6% NaOCl and EndoVac System® to irrigation/aspiration. After instrumentation, the specimens were divided into two groups: 37% phosphoric acid solution or 17% EDTA. RESULTS: The results demonstrated that 37% phosphoric acid was significantly more effective in removing smear layer and AHTD than 17% EDTA (Mann-Whitney, P <0.05). It was shown that both 37% phosphoric acid and 17% EDTA are effective agents in the removal of smear layer and debris, but better results were obtained with the use of 37% phosphoric acid. CONCLUSION: The results suggest that this solution can be a potential alternative to remove smear layer after root canal preparation.

Biodentine: um substituto ao MTA? / Biodentine: an alternative to MTA?

Objetivo: o objetivo desse estudo é realizar uma revisão de literatura em relação às propriedades físico- -químicas e biológicas do Biodentine, seu emprego na Endodontia e discutir, com base nas evidências científicas encontradas na literatura, se esse material poderá ser um substituto ao MTA. Métodos: foi realizada uma busca na literatura na base de dados PubMed, usando os termos em inglês: Biodentine, calcium silicate, MTA, properties, setting time, radiopacity, solubility, physicochemical properties, porosity, hydration, biocompatibility, bioactivity, microhardness, compressive strength, bond strength, irrigants, furcal perforation, retrograde filling material, revitalization, revascularization, endodontics, apexification. Cinquenta artigos foram incluídos. Resultados: os artigos revisados sugerem que o Biodentine tem características favoráveis e que tem alcançado resultados promissores em relação ao MTA. Conclusão: o Biodentine pode ser considerado um eventual substituto ao MTA (AU).

Introduction: This study aim to review the literature about the physicochemical and biological characteristics of Biodentine, a cement used in endodontics, and discussed whether this material might be an alternative to MTA according to the scientific evidence found in the literature. Methods: A literature search was performed on PubMed using the following terms: Biodentine, calcium silicate, MTA, properties, setting time, radiopacity, solubility, physicochemical properties, porosity, hydration, biocompatibility, bioactivity, microhardness, compressive strength, bond strength, irrigants, furcal perforation, retrograde filling, revitalization, revascularization, endodontics, apexification. Fifty studies met inclusion criteria. Results: Biodentine seems to have favorable characteristics, and the results of its use are promising when compared with those of MTA. Conclusion: Biodentine may be a possible alternative to MTA (AU).

Effect of previous irrigation with chlorhexidine on the push-out bond strength of a calcium silicate-based material.

This study evaluated the effect of previous irrigation with chlorhexidine (CHX) on the bond strength of a calcium silicate-based material, Biodentine, when used for furcal repair. Furcal perforations were produced in 30 extracted mandibular molars. Teeth were divided into 3 groups according to the irrigant used: distilled water (DW), CHX followed by DW (CHX), and CHX followed by ethylenediaminetetraacetic acid (EDTA) and DW (CHX/EDTA). Biodentine was used to repair the perforations. A push-out bond strength test was performed after 7 days, and data were statistically analyzed using Kruskal-Wallis and Dunn tests (P < 0.05). The CHX/EDTA group showed significantly lower values than the DW and CHX groups (P < 0.05). The failure mode of the DW group was mainly mixed, while that of the CHX group was cohesive. The CHX/EDTA group exhibited adhesive and mixed failures. Irrigation with CHX prior to furcation repair did not result in a statistically significant difference, compared to the use of DW, in the push-out bond strength of Biodentine.

Influência da técnica de preparo apical na desinfecção e modelagem dos canais radiculares: revisão de literatura / Influence of apical preparation technique on root canal disinfection and shaping: literature review

Introdução: um dos objetivos da terapia endodôntica é a redução dos fatores microbianos no interior dos canais radiculares, o que pode ser conseguido por meio do preparo químico-mecânico (PQM). O PQM tem como finalidade criar um ambiente propício à condição de reparo, por meio da limpeza e modelagem do sistema de canais radiculares (SCR), que associa a ação mecânica dos instrumentos ao uso de substâncias químicas auxiliares. Em relação ao limite apical desse preparo e ao diâmetro apical final da instrumentação, podemos observar que não há consenso entre os profissionais. Introdução: o objetivo do presente estudo foi avaliar, por meio de uma revisão de literatura, a eficiência de duas técnicas no preparo e desinfecção do terço apical do SCR: a técnica de ampliação foraminal e a técnica de batente apical com manutenção da patência foraminal. Métodos: foi realizada uma busca nas bases de dados PubMed, Medline, BBO, Lilacs e SciELO, usando os seguintes termos: canal radicular, forame apical, endodontia, lima de patência, tamanho apical, lima apical final, preparo biomecânico, ampliação foraminal, comprimento de trabalho, anatomia dental, tratamento endodôntico, patência foraminal, preparo do canal radicular e batente apical. Cada um desses termos foi combinado utilizando os operadores booleanos E/OU. Após leitura dos resumos, 65 artigos foram selecionados e incluídos nessa revisão. Resultados: os resultados demonstraram que o alargamento do terço apical, seja com ou sem ampliação foraminal, parece favorecer o prognóstico do tratamento endodôntico, devido à redução do conteúdo infeccioso em toda a extensão do SCR. A manutenção da patência foraminal é um fator essencial para um PQM adequado quando a técnica de batente apical é realizada. Conclusão: conclui-se que preparos apicais mais amplos promovem resultados mais previsíveis, e que a ampliação foraminal possibilita o melhor debridamento e desinfeção do SCR (AU).

Introduction: Endodontic therapy should reduce the microbial load within the root canals, which can be achieved during chemomechanical preparation (CMP). The purpose of CMP of the root canal system (RCS) is to create a favorable environment for healing. CMP associates the mechanical action of instruments with the use of auxiliary chemical substances. There is no consensus among professionals about what should be the diameter of the apical foramen after CMP. This literature review evaluated the efficiency of two apical preparation techniques: foraminal enlargement and apical stop with maintenance of foraminal patency. Material and methods: A literature search was conducted in PubMed, Medline, BBO, Lilacs and Scielo using the following terms: root canal, apical foramen, endodontics, patency file, apical size, master apical file, biomechanical preparation, foraminal enlargement, working length, dental anatomy, endodontic treatment, foraminal patency, root canal preparation, and apical stop. All terms were combined using the Boolean operators AND/OR. After the abstracts were analyzed, 65 full texts were selected and included in this review. Results: The enlargement of the apical third, with or without foraminal enlargement, seems to improve endodontic treatment prognosis due to the reduction of infectious contents throughout the RCS. Foraminal patency is essential for adequateCMP when the apical stop technique is performed. Conclusion: Apical preparations with a greater diameter have more predictable results, and foraminal enlargement ensures better debridement and disinfection of the RCS (AU).

Efeito de diferentes protocolos de irrigação final na remoção da smear layer / Effect of different protocols of final irrigation on smear layer removal

Objetivo: esse estudo avaliou o efeito de protocolos de irrigação final, associados ao uso de EDTA e QMix, na remoção de smear layer. Métodos: foram utilizados 40 dentes humanos com canal único. Os canais foram instrumentados com sistema ProTaper Universal SX-F3. As substâncias químicas utilizadas durante o preparo foram hipoclorito de sódio a 5,25% (NaOCl) ou clorexidina a 2% (CHX) gel. Terminado o preparo, os dentes foram divididos em oito grupos, de acordo com os irrigantes: G1) NaOCl 5,25% + EDTA 17% + NaOCl 5,25%; G2) NaOCl 5,25% + EDTA 17% + água destilada (AD); G3) NaOCl 5,25% + QMix + NaOCl 5,25%; G4) NaOCl 5,25% + QMix + AD; G5) CHX 2% gel + EDTA 17% + CHX 2% solução; G6) CHX 2% gel + EDTA 17% + AD; G7) CHX 2% gel + QMix + CHX 2% solução e G8) CHX 2% gel + QMix + AD. As amostras foram avaliadas por microscopia eletrônica de varredura ambiental, antes e após os protocolos de irrigação final. As imagens foram classificadas por escores, em relação à presença de smear layer, e os dados foram analisados pelos testes de Kruskal-Wallis e de Mann-Whitney. Resultados: o G1 mostrou os melhores resultados em relação à remoção de smear layer (p < 0,05). A CHX gel 2% mostrou menor formação de smear layer, quando comparada ao NaOCl, após o preparo biomecânico; e o NaOCl apresentou melhor limpeza como irrigante final (p < 0,05). Conclusões: o NaOCl como irrigante final, combinado ao EDTA, mostrou melhor capacidade de remoção da smear layer (AU).

Introduction: This study evaluated the effect of different final irrigation protocols using EDTA and QMix on smear layer removal. Methods: The root canals of 40 single-rooted human teeth were prepared with ProTaper Universal SX - F3. The substances used were 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine gel (chlorhexidine), 2% chlorhexidine solution and distilled water. The teeth were divided into 8 groups, according to the irrigant used: G1: 5.25% NaOCl + 17% EDTA + 5.25% NaOCl; G2: 5.25% NaOCl + 17% EDTA + distilled water; G3: 5.25% NaOCl + QMix + 5.25% NaOCl; G4: 5.25% NaOCl + QMix + DW; G5: 2% chlorhexidine gel + 17% EDTA + 2% chlorhexidine solution; G6: 2% chlorhexidine gel + 17% EDTA + distilled water; G7: 2% chlorhexidine gel + QMix + 2% chlorhexidine solution; and G8: 2% chlorhexidine gel + QMix + distilled water. Samples were evaluated under environmental scanning electron microscopy (ESEM) before and after irrigation. ESEM images were classified according to smear layer scores, and the Kruskal-Wallis and Mann-Whitney tests were used for statistical analyses. Results: Group 1 had the best results for smear layer removal (p<0.05). Smear layer formation was lower when 2% chlorhexidine gel was used after cleaning and shaping than when the irrigant was 5.25% NaOCl, and 5.25% NaOCl had the best cleaning ability as a final irrigant. Conclusion: 5.25% NaOCl combined with EDTA was the best final irrigant for smear layer removal (AU).