Effect of Radiotherapy and Taper of Root Canal Preparation on the Biomechanical Behavior of Mesial Roots of Mandibular Molars.

INTRODUCTION: This study aimed to investigate the effect of radiotherapy and taper of root canal preparation on the biomechanical behavior of mesial roots of mandibular molars. METHODS: Eighty mandibular molars with 2 canals in the mesial root were randomly allocated into 2 groups (n = 40): one group underwent irradiation (60 Gy), while the other did not. Subsequently, the mesial roots were sectioned and each group was subdivided into 5 subgroups (n = 8), according to the preparation taper: no preparation (control); 25.03; 25.04; 25.06; and 25.08. All groups were considered homogeneous regarding their dimensions, weight, and morphology. The prepared specimens were embedded in cylindrical plastic molds and subjected to a cyclic fatigue test. A failure analysis was performed according to the extension and course of the fractures. Two-way ANOVA, Tukey's post-hoc, Fisher's exact, and Kaplan-Meier tests were conducted to evaluate the obtained data (α = 5%). RESULTS: Fatigue resistance decreased as the taper of the preparation increased (P < .05). Preparation 25.03 presented significantly higher values only than 25.08 (P < .05), while 25.04, 25.06, and 25.08 were considered similar (P > .05). Irradiation significantly reduced the biomechanical performance (P < .05). Survival analysis corroborated these findings. There were no differences in the distribution of fracture types among the groups (P > .05). CONCLUSION: The biomechanical behavior of the mesial roots of the mandibular molars decreased significantly in the face of irradiation and as the taper of the preparation increased.

The use of sonic and ultrasonic activation of endodontic sealer to improve sealer filling quality in the root canal: a scoping review.

This scoping review aimed to map whether the use of sonic and ultrasonic methods to activate the endodontic sealer improves the sealer filling quality in the root canal, considering the bond strength and intratubular penetration to the root dentin as evaluation criteria. The study protocol was prospectively registered and is available online ( https://osf.io/x5fma/ ). Reporting was based on PRISMA Extension for Scoping Reviews. The search was performed in Embase, PubMed, Scopus, and Web of Science. We selected studies without time and language restrictions that used sonic or ultrasonic methods to activate endodontic sealer, whose outcomes were bond strength and intratubular penetration. Three researchers independently selected the articles and collected data. Of 1422 articles, 19 were read in full and 13 studies were included. The vast majority of studies opted for direct activation of the endodontic sealer. The most investigated sealers were the epoxy resin-based sealers, and the ultrasonic activation method was the most explored. For the bond strength outcome, there was a trend toward higher values when the sealer was activated ultrasonically, but the findings seem to be divergent. The sonic activation was not effective for its intended purpose. For the outcome of intratubular penetration, the vast majority of studies indicate that the use of sonic and ultrasonic methods to activate the endodontic sealer is capable of increasing intratubular penetration. The use of sonic and ultrasonic methods to directly activate the endodontic sealer can increase the intratubular penetration of the sealer, but their benefits on the bond strength are uncertain.

Efficacy of calcium hypochlorite in disinfection of gutta-percha cones contaminated with Candida albicans.

This study aimed to compare the efficacy of 2.5% sodium hypochlorite (NaOCl), 2.5% calcium hypochlorite [Ca(OCl)2], and 2% chlorhexidine (CHX) in the rapid disinfection of gutta-percha cones contaminated with Candida albicans. The minimum inhibitory and minimum fungicidal concentrations of each solution for C. albicans were determined and the ability of each solution to destroy and inhibit biofilm in culture wells was tested. In addition, ninety-eight gutta-percha cones contaminated with the fungal suspension were disinfected according to the type of solution (2.5% NaOCl, 2.5% Ca(OCl)2 or 2% CHX) in its different application methods (without agitation, ultrasonic agitation or agitation with Easy Clean), and regarding the exposure time to each irrigating solution (1 or 5 min). Next, the samples were checked for turbidity and evaluation of viable colonies. The compounds that showed the best performance in biofilm destruction were NaOCl and Ca(OCl)2 at a concentration of 2xMIC (p < 0.001). Regarding inhibited biofilm, the only compound that was effective at all MIC concentrations tested was 2.5% Ca(OCl)2 (p < 0.0001). Regarding the viable colonies, all solutions were effective concerning the control group, for all application methods, in 1 and 5 min (p < 0.05). The densitometer reading showed that CHX was the only effective solution in all application methods performed (p < 0.05). The results demonstrate that all tested solutions were effective in the rapid decontamination of cones contaminated with C. albicans.

Effect of sodium/calcium hypochlorite on adhesion and adaptation of fiber posts luted with a dual resin cement.

This study aimed to evaluate the effect of different concentrations of sodium hypochlorite (NaOCl) and calcium hypochlorite [Ca(OCl)2] on the bond strength and adaptation of glass fiber posts luted with a dual-curing resin cement. Fifty decoronated premolars were sectioned 14 mm from the apex and endodontically treated. The root canal filling was partially removed. The specimens were divided into 5 groups (n=10) according to the irrigant for post space irrigation: 0.9% sodium chloride (NaCl), (control); 2.5% NaOCl; 5.25% NaOCl; 2.5% Ca(OCl)2; and 5.25% Ca(OCl)2. For each group, irrigation was performed with 5 ml of solution. Afterward, the posts were luted with a dual-curing resin cement. One slice from each third was obtained and submitted to the push-out test and failure modes analysis. An additional slice from the middle third was submitted to confocal images for analysis of adaptation failures (gaps). Two-way ANOVA, Tukey's post-hoc, Kruskal-Wallis with Bonferroni adjusted, and chi-square tests, analyzed data. The group treated with 5.25% NaOCl showed lower bond strength values and generated more cohesive failures compared to the control (p < 0.05). Bond strength decreased from coronal to apical in the post space (p < 0.001). The groups treated with NaOCl had the highest percentages of gaps compared to the control (p < 0.05). Regardless of concentration, Ca(OCl)2 did not influence the bond strength and the occurrence of gaps (P > 0.05). Ca(OCl)2 is a good option for irrigating the post space before luting a fiber post with a dual-curing resin cement.

Effect of calcium hypochlorite and sodium thiosulfate on the bond strength to pulp chamber dentin: A laboratory investigation.

This study aimed to compare the effect of sodium hypochlorite (NaOCl) and calcium hypochlorite [Ca(OCl)2 ] on the bond strength to pulp chamber dentin when followed or not by the use of sodium thiosulfate (Na2 S2 O3 ). The pulp chamber of fifty human molars were divided into five groups (n = 10) according to the immersion protocol: 2.5% NaOCl; 2.5% NaOCl + 5% Na2 S2 O3 ; 2.5% Ca(OCl)2 ; 2.5% Ca(OCl)2 + 5% Na2 S2 O3 ; and 0.9% sodium chloride (NaCl; control). Subsequently, the samples were restored with resin composite. Three sticks each were obtained and subjected to microtensile testing. SEM/EDS analyses of the pulp chamber roof (n = 8) were carried out for mineral quantification. Elemental analysis data were investigated via one-way ANOVA and Tukey's post hoc, and bond strength data by post hoc pairwise comparisons using the Kruskal-Wallis test. Use of 2.5% NaOCl was associated with the lowest value of bond strength, while 2.5% Ca(OCl)2 had similar bond strength to that of the 0.9% NaCl control. Using 5% Na2 S2 O3 was able to increase the bond strength after 2.5% NaOCl, but not after 2.5% Ca(OCl)2 . The group treated only with 2.5% Ca(OCl)2 had a higher Ca/P ratio on the dentin surface. Dentin treated with Ca(OCl)2 was not affected by Na2 S2 O3 and showed bond strength similar to the 0.9% NaCl.

Effect of sodium/calcium hypochlorite on adhesion and adaptation of fiber posts luted with a dual resin cement

Abstract This study aimed to evaluate the effect of different concentrations of sodium hypochlorite (NaOCl) and calcium hypochlorite [Ca(OCl)2] on the bond strength and adaptation of glass fiber posts luted with a dual-curing resin cement. Fifty decoronated premolars were sectioned 14 mm from the apex and endodontically treated. The root canal filling was partially removed. The specimens were divided into 5 groups (n=10) according to the irrigant for post space irrigation: 0.9% sodium chloride (NaCl), (control); 2.5% NaOCl; 5.25% NaOCl; 2.5% Ca(OCl)2; and 5.25% Ca(OCl)2. For each group, irrigation was performed with 5 ml of solution. Afterward, the posts were luted with a dual-curing resin cement. One slice from each third was obtained and submitted to the push-out test and failure modes analysis. An additional slice from the middle third was submitted to confocal images for analysis of adaptation failures (gaps). Two-way ANOVA, Tukey's post-hoc, Kruskal-Wallis with Bonferroni adjusted, and chi-square tests, analyzed data. The group treated with 5.25% NaOCl showed lower bond strength values and generated more cohesive failures compared to the control (p < 0.05). Bond strength decreased from coronal to apical in the post space (p < 0.001). The groups treated with NaOCl had the highest percentages of gaps compared to the control (p < 0.05). Regardless of concentration, Ca(OCl)2 did not influence the bond strength and the occurrence of gaps (P > 0.05). Ca(OCl)2 is a good option for irrigating the post space before luting a fiber post with a dual-curing resin cement.

Resumo Este estudo teve como objetivo avaliar o efeito de diferentes concentrações de hipoclorito de sódio (NaOCl) e hipoclorito de cálcio [Ca(OCl)2] na resistência de união e adaptação de pinos de fibra de vidro cimentados com um cimento resinoso dual. Cinquenta pré-molares tiveram suas coroas removidas, foram seccionados a 14 mm do ápice e tratados endodonticamente. A obturação do canal radicular foi parcialmente removida. Os espécimes foram divididos em 5 grupos (n=10) de acordo com o irrigante para irrigação do espaço do pino: cloreto de sódio 0.9% (NaCl), (controle); NaOCl 2.5%; NaOCl 5.25%; Ca(OCl)2 2.5%; e Ca(OCl)2 5.25%. Para cada grupo, a irrigação foi realizada com 5 ml da solução. Posteriormente, os pinos foram cimentados com um cimento resinoso dual. Uma fatia de cada terço foi obtida e submetida ao teste push-out e análise dos modos de falha. Um corte adicional do terço médio foi submetido a imagens confocais para análise de falhas de adaptação (gaps). Os dados foram analisados pelos testes ANOVA de duas vias, post-hoc de Tukey, Kruskal-Wallis com ajuste de Bonferroni e qui-quadrado. O grupo tratado com NaOCl 5.25% apresentou menores valores de resistência de união e gerou mais falhas coesivas em relação ao controle (p < 0.05). A resistência de união diminuiu de coronal para apical no espaço do pino (p < 0.001). Os grupos tratados com NaOCl apresentaram os maiores percentuais de gaps em relação ao controle (p < 0.05). Independentemente da concentração, o Ca(OCl)2 não influenciou a resistência de união e a ocorrência de gaps (P > 0.05). O Ca(OCl)2 é uma boa opção para irrigar o espaço do pino antes de cimentar um pino de fibra com um cimento resinoso dual.

Interactions Between Calcium Hypochlorite and Irrigants Commonly Used in Endodontic Practice: A Chemical Analysis.

INTRODUCTION: This study aimed to identify possible products resulting from chemical interactions between calcium hypochlorite (Ca[OCl]2) and other irrigants for endodontic use using electrospray ionization quadrupole time-of-flight mass spectrometry. METHODS: The 5.25% Ca(OCl)2 was associated with either 70% ethanol solution, distilled water, saline solution (0.9% sodium chloride), 5% sodium thiosulfate, 10% citric acid, 17% ethylenediaminetetraacetic acid (EDTA), or 2% chlorhexidine (CHX). The reaction ratio was 1:1 and the products obtained were analyzed by electrospray ionization quadrupole time-of-flight mass spectrometry. RESULTS: The interactions between Ca(OCl)2 and CHX generated an orange-brown precipitate, without identification of para-chloroaniline and between Ca(OCl)2 and sodium thiosulfate, a milky-white precipitate. Furthermore, when the oxidizing agent was associated with EDTA and citric acid, chlorine gas was released. As for the other associations, 70% ethanol, distilled water, and saline solution, no precipitation or gas release occurred. CONCLUSIONS: The orange-brown precipitate occurs due to the chlorination of guanidine nitrogens, and the milky-white precipitate is due to the partial neutralization of the oxidizing agent. The release of chlorine gas occurs due to the low pH of the mixture, which results in the rapid formation and decomposition of chlorine. In this context, an intermediate rinsed with distilled water, saline solution, and ethanol between Ca(OCl)2 and CHX, citric acid, and EDTA seems to be appropriate to prevent the formation of by-products when these irrigants need to be used in the canal. Furthermore, if it is necessary to use sodium thiosulfate, a larger volume of the solution must be used compared to that used for the oxidizing solution.

Associação entre a periodontite apical e as doenças cardiovasculares: uma revisão da literatura / Association between apical periodontitis and cardiovascular diseases: a review of the literature

Objetivo: o presente estudo tem como objetivo revisar os dados disponíveis na literatura para verificar se a periodontite apical (PA) é um fator de risco para as doenças cardiovasculares (DCVs). Materiais e Métodos: foi realizada uma busca nas bases de dados do Pubmed e Google Acadêmico sobre a possível associação da PA com o desenvolvimento de problemas cardiovasculares. Após os critérios de seleção, foram incluídos 8 artigos científicos para serem detalhadamente abordados. Revisão de literatura: embora a PA seja um processo inflamatório local, sua patogênese pode influenciar no desenvolvimento de complicações sistêmicas. Partindo do princípio que uma resposta inflamatória localizada é capaz de acarretar à liberação e ativação de mediadores pró-inflamatórios sistêmicos, como as citocinas interleucinas e fatores de necrose tumoral, alguns autores sugerem uma possível associação entre a PA crônica e as DCVs, devido o potencial de surgimento de danos endoteliais e formação de ateromas. Discussão: embora ainda seja questionável a correlação existente entre lesões inflamatórias periapicais e doenças sistêmicas, devido principalmente ao descrédito em que o assunto era tratado no passado e na quantidade limitada de informações conclusivas disponíveis atualmente, os dados revisados neste trabalho propõem que existe uma associação positiva entre a PA e as DCVs, podendo-se verificar uma maior prevalência de PA em pacientes com problemas cardiovasculares. Conclusão: tem-se disponível cientificamente uma quantidade limitada de achados. Portanto, sugere-se a realização de mais pesquisas sobre o tema, objetivando a busca por evidências relevantes e bem fundamentadas sobre esta associação.

Aim: The present study aims to review the data available in the literature to verify whether apical periodontitis (AP) is a risk factor for cardiovascular diseases (CVDs). Materials and Methods: a search was carried out in the databases of Pubmed and Google Scholar about a possible association of AP with the development of cardiovascular problems. After the selection criteria, 8 scientific arti-cles were included to be analyzed in detail. Literature Review: although BP is a local inflammatory process, its pathogenesis can result in the development of systemic complications. Assuming that a localized inflammatory response is capable of causing the release and activation of systemic pro-inflammatory mediators, such as interleukin cytokines and tumor necrosis factors, some automatic effects are a possible association between a chronic AP and CVDs, due to the potential for the emergence of en-dothelial damage and atheroma. Discussion: although the correlation between periapical inflammatory lesions and systemic diseases is still questionable, mainly due to the discredit in which the subject was treated in the past and the limited amount of conclusive information currently available, the data reviewed in this paper propose that there is a positive association between AP and CVDs, with a higher prevalence of AP in patients with cardiovascular problems. Conclusion: a limited amount of findings are scientifically available. Therefore, it is suggested to carry out more research on the subject, aiming the search for relevant and well-grounded evidence on this association

Efeito da crioterapia intracanal no controle da dor pós-operatória após terapia endodôntica: uma revisão de literatura / Effect of intracanal cryotherapy on postoperative pain control after endodontic therapy: a literature review

Objetivo: O objetivo desta revisão de literatura é investigar e analisar criticamente o uso da crioterapia intracanal durante o tratamento endodôntico, visando através dos achados científicos disponíveis elaborar argumentos sólidos que justifiquem optar ou não pela realização de tal protocolo auxiliar durante a intervenção endodôntica. Revisão de literatura: A alternativa terapêutica conhecida como crioterapia é uma técnica existente há anos, a qual tem sido frequentemente aplicada na Medicina para o tratamento da dor e cuidados pós-operatórios. Recentemente, o uso da crioterapia na Endodontia, através de um protocolo de irrigação final do canal radicular, foi examinado em vários ensaios clínicos randomizados. Discussão: Os estudos revisados demonstraram que a utilização de soro fisiológico frio como agente irrigante final ao preparo químico-mecânico, tem potencial para reduzir os níveis de dor de uma possível sintomatologia dolorosa pós-tratamento endodôntico, além de que, trata-se de um método de fácil aplicação e baixo custo. Conclusão: Embora se tenha poucos estudos sobre o tema, as evidências científicas disponíveis e revisadas neste artigo embasam com propriedade o efeito da crioterapia intracanal na redução da dor pós-operatória proveniente de uma intervenção endodôntica. No entanto, novos estudos são necessários para averiguar possíveis efeitos deletérios e para a elaboração de um protocolo previsível e seguro.

Aim: The aim of this literature review is to investigate and critically analyze the use of intracanal cryotherapy during endodontic treatment and, through scientific findings, elaborate well grouded references that justify or not, carrying out such auxiliary protocol during endodontic intervention. Literature Review: The therapeutic alternative known as cryotherapy is a technique that has existed for years, which has been frequently applied in Medicine for the treatment of pain and postoperative care. Recently, the use of cryotherapy in Endodontics, through a final root canal irrigation protocol, has been examined in several randomized clinical trials. Discussion:The reviewed studies showed that the use of cold saline solution as a final irrigating agent for chemical-mechanical preparation has the potential to reduce pain levels of a possible painful symptomatology after endodontic treatment, in addition to being a method of easy appli-cation and low cost. Conclusion: Although there are few studies on the subject, scientific evidences available and reviewed in this article properly support the effect of intracanal cryotherapy in reducing the postoperative pain of an endodontic intervention. However, new studies should be placed to investigate possible harmful effects and to prepare a predictable and safe protocol.

Infecções virais na prática odontológica: riscos e prevenção / Viral infections in dental practice: risks and prevention

Objetivo: revisar a literatura sobre as principais patologias virais associadas à área odontológica, tais como varicela, herpes zoster, sarampo, mononucleose infecciosa, síndrome da imunodeficiência adquirida (Aids), hepatites virais e infecções associadas ao herpes-vírus simples (HSV) e ao papilomavírus humano (HPV), com o intuito de descrever as manifestações orais relacionadas a essas patologias e informar e esclarecer aos profissionais da área odontológica os riscos e os cuidados durante a prática clínica. Métodos: foi realizada uma busca nas bases de dados Google Acadêmico, SciELO, LILACS e PubMed sobre o tema infecções virais na prática odontológica. Foram incluídos nesta revisão 31 artigos, publicados no período de 2000 a 2020. Também foram utilizados como fonte bibliográfica 4 livros que abordavam o assunto em questão. Revisão de literatura: o consultório odontológico é um local propício à propagação de agentes biológicos patógenos causadores de infecção, nos quais se incluem os vírus. O profissional da área deve adotar medidas de biossegurança para evitar possíveis infecções. As precauções universais eficazes na redução do risco ocupacional baseiam-se no uso de equipamentos de proteção individual (EPIs), na prevenção da exposição a sangue e fluidos corpóreos, na prevenção de acidentes com instrumentos perfurocortantes e no descarte adequado dos resíduos contaminados. Considerações finais: as infecções virais representam um assunto relevante para o odontólogo, pois, além de serem transmissíveis por vários meios, também apresentam manifestações orais. Dessa forma, o cirurgião-dentista deve ter conhecimento suficiente sobre o tema para nortear a sua conduta clínica.(AU)

Objective: the present study aims to review the literature regarding the main viral pathologies associated with the dental field, such as chickenpox, herpes zoster, measles, infectious mononucleosis, acquired immunodeficiency syndrome (AIDS), viral hepatitis, and infections associated with herpes simplex virus (HSV) and human papillomavirus (HPV), in order to describe the oral manifestations related to these pathologies, and inform and clarify to the dental professionals the risks and care during clinical practice. Methods: a search was performed using Google Scholar, SciELO, LILACS and PubMed databases on the topic of viral infections in dental practice. This review included 31 articles, published from 2000 to 2020. Four books on the subject were also used as a bibliographic source. Literature review: the dental office is a place susceptible to the spread of pathogenic biological agents that cause infection, including viruses. The professional must adopt biosafety measures to avoid possible infections. Universal precautions that are effective in reducing occupational risk are based on the use of personal protective equipment (PPE), the prevention of exposure to blood and bodily fluids, the prevention of accidents with sharps, and the proper disposal of contaminated waste. Final considerations: viral infections represent a relevant issue for the dentist, because in addition to being transmissible through various means, they also present oral manifestations. Thus, the dentist must have sufficient knowledge on the subject to guide his clinical conduct.(AU)

Different techniques for the treatment of teeth with an incomplete root development and pulp necrosis: a systematic review / Diferentes técnicas para o tratamento de dentes com rizogênese incompleta e necrose pulpar: uma revisão sistemática

Introduction: The objective of this systematic review was to compare the apexification techniques of calcium hydroxide (Ca(OH)2), or mineral trioxide aggregate (MTA), with the pulp regeneration technique, using cohort studies, and non-randomized and randomized clinical trials. Methods: The methodology was based on electronic research in the following databases: PubMed, MEDLINE, Google Scholar, SciELO, and LILACS. In addition, a manual search was carried out using the references that were listed in the articles found. Results: A total of 403 potentially eligible studies were found, with seven being included in the inclusion criteria of this systematic review. The seven studies involved a total of 312 teeth. The minimum time of a follow-up period was 12 months. The irrigation solution most used was sodium hypochlorite, for both of the apexification and revascularization techniques. The medication commonly chosen in the apexification groups was Ca(OH)2, with antibiotic triple paste in the revascularization groups. The clinical rate of success in the groups treated with revascularization varied from 76% to 100%, while in the groups treated with apexification, it ranged from 68% to 100%. Only two studies reached a success rate equal to 100%. Conclusions: Variable levels of evidence were observed in relation to the treatments. However, it was confirmed that revascularization is an excellent option since its outcomes produced a greater gain of thickness and root length, besides developing a decrease in the apical foramen.

Introdução: O objetivo desta revisão sistemática foi comparar as técnicas de apexificação, com hidróxido de cálcio (Ca(OH)2) ou agregado trióxido mineral (MTA), com a técnica de regeneração pulpar, utilizando estudos coorte, ensaio clínico não randomizado e randomizado. Métodos: A metodologia foi baseada em pesquisa eletrônica nas seguintes bases de dados: PubMed, MEDLINE, Google Acadêmico, SciELO e LILACS. Além disso, foi realizada uma pesquisa manual utilizando as referências listadas nos artigos encontrados. Resultados: Foram encontrados 403 estudos potencialmente elegíveis, sendo sete incluídos nos critérios de inclusão desta revisão sistemática. Os sete estudos envolveram um total de 312 dentes. O tempo mínimo de um período de acompanhamento foi de 12 meses. A solução de irrigação mais utilizada foi o hipoclorito de sódio, para as técnicas de apexificação e revascularização. O medicamento comumente escolhido nos grupos de apexificação foi o Ca(OH)2, com pasta tripla antibiótica nos grupos de revascularização. A taxa clínica de sucesso nos grupos tratados com revascularização variou de 76% a 100%, enquanto nos grupos tratados com apexificação variou de 68% a 100%. Apenas dois estudos atingiram uma taxa de sucesso igual a 100%. Conclusões: Níveis variáveis de evidência foram observados em relação aos tratamentos. No entanto, confirmou-se que a revascularização é uma excelente opção, pois seus desfechos produzem maior ganho de espessura e comprimento radicular, além de diminuir o forame apical.

O impacto da patência apical para o sucesso do tratamento endodôntico: uma revisão de literatura / The impact of apical patency for the success of endodontical treatment: a review of the literature

Objetivo: analisar a importância da realização da patência apical durante o preparo químico-mecânico do sistema de canais radiculares, enfatizando os prós e contras do procedimento. Materiais e método: foi realizada uma busca na base de dados PubMed e na Biblioteca Virtual em Saúde sobre o tema patência apical no contexto da terapia endodôntica. Foram incluídos nesta revisão 30 artigos, publicados no período de 1974 a 2018. Revisão de literatura: a patência apical consiste na limpeza passiva do canal cementário sem ampliação da constrição apical, realizada com instrumentos finos e flexíveis, a fim de manter o forame apical livre de raspas de dentina, remanescentes pulpares e microrganismos. Tal manobra é indicada para dentes com necrose pulpar. Contudo, em dentes com polpa necrótica sem lesão perirradicular, em que há possibilidade de vitalidade do coto pulpar, ou em casos de biopulpectomia, esse procedimento não tem sido bem aceito, devido à preservação da vitalidade do coto pulpar ser muito importante para o reparo periapical. Considerações finais: a etapa correspondente ao preparo químico-mecânico é de extrema importância para se ter êxito na intervenção endodôntica. Durante o preparo dos canais radiculares, o acúmulo de debris dentinários no terço apical pode gerar perda no comprimento de trabalho. Dessa forma, a patência apical impede que essa dentina seja compactada nesta porção do canal, o que favorece modelagem, desinfecção, irrigação e, posteriormente, obturação adequada dessa importante região do sistema de canais radiculares. (AU)

during the chemical-mechanical preparation of the root canal system, emphasizing the pros and cons of this procedure. Materials and method: a search in the literature for relevant articles on the topic apical patency in the context of endodontic therapy was carried out by consulting the databases of PubMed and the Virtual Health Library. A total of 30 articles, published between 1974 and 2018, were selected for inclusion in this literature review. Literature review: the apical patency consisted of passive cleaning of the cementum canal without enlargement of the apical constriction, performed with thin and flexible instruments, in order to maintain the apical foramen free of dentin scrapings, remaining pulp and microorganisms. This maneuver is indicated for teeth with pulp necrosis. However, in teeth with necrotic pulp without periradicular lesion, in which there is possibility of vitality of the pulp stump, or cases of biopulpectomy, this procedure has not been well accepted, due to the preservation of the vitality of the pulp stump being very important for the periapical repair. Final considerations: the stage corresponding to the chemical-mechanical preparation is extremely important to succeed in endodontic intervention. During the preparation of the root canals, the accumulation of dentinal debris in the apical third can cause loss of working length. Thus, the apical patency prevents this dentin from being compacted in this portion of the canal, which favors the modeling, disinfection, irrigation and subsequent filling of this important region of the root canal system. (AU)

Novas alternativas terapêuticas para prevenção do câncer labial com produtos à base de extratos naturais com potencial fotoprotetor: uma revisão de literatura

Objetivo: o presente trabalho realiza uma revisão da literaturaa respeito do potencial fotoprotetor de extratos naturaiscontra os efeitos deletérios da radiação solar, dandoênfase à carcinogênese oral e ressaltando os principaistipos de plantas fotoprotetoras nos cenários mundiale nacional. Revisão de literatura: atualmente os extratosde plantas vêm ganhando destaque em pesquisas científicaspor serem considerados uma fonte de fotoproteçãonatural. Vários estudos avaliaram a ação fotoprotetorade produtos naturais contra a radiação ultravioleta, comobjetivo de buscar novas opções de plantas medicinais,para evitar o desenvolvimento de doenças relacionadasà radiação ultravioleta. Alguns extratos representam umafonte segura e eficaz, com condições de contribuir positivamentena prevenção do câncer labial. Entretanto,este campo de estudo é amplo, e muitos biomas regionaiscom potencial ainda não foram amplamente estudados.Dessa forma, mais pesquisas experimentais e clínicassão necessárias para consolidar a ação de produtosnaturais na proteção contra o câncer labial e o câncer depele. Considerações finais: além dos benefícios fotoprotetoresencontrados em extratos de plantas, a utilizaçãode princípios ativos derivados de produtos naturais podegerar um relevante impacto social, uma vez que estimulaa economia da região, promovendo, assim, uma diferenciaçãono crescimento regional.