Apical periodontitis as an aggravating factor for the severity of rheumatoid arthritis: An animal study.

AIM: The present study investigated the influence of apical periodontitis (AP) on the severity of rheumatoid arthritis (RA) using a Wistar rat model. METHODOLOGY: Forty male Wistar rats were distributed across four groups (n = 10) based on the induction of RA and AP: Control, RA, AP, and RA + AP. RA was induced through two immunisations with type II collagen emulsified in incomplete Freund's adjuvant, followed by one immunisation with complete Freund's adjuvant. After 21 days of RA induction, AP was induced by exposing the pulp of four molars. Animals were euthanized after 28 days of pulp exposure. Through the experiment, visual and behavioural assessments tracked RA development and the knees and hind paw joints were measured. Micro-computed tomography scans of knees and hind paws, as well as mandibles and maxillae, were conducted to evaluate RA severity and the presence of AP, respectively. Serum samples were collected to analyse proinflammatory cytokines (IL-1ß, IL-2, IL-17, and TNF-α). Non-parametric data were analysed using the Kruskal-Wallis test followed by Student-Newman-Keuls test, while one-way anova followed by Tukey's test was performed for parametric data. A significance level of 5% was employed. RESULTS: All molars submitted to access cavity developed AP. All joints subjected to arthritis induction developed the disease, with AP + RA demonstrating a higher arthritis severity when compared to the RA group (p < .05). RA + AP group displayed a significantly larger hind paw and knee circumference compared to the RA group (p < .05). Micro-CT images of RA and RA + AP groups revealed joints with erosions and bone deformities, with a significantly lower bone surface density, lower trabecular number and higher trabecular separation in the hind paw and a significantly lower percent bone volume and higher trabecular separation in the knees of RA + AP group compared to RA group (p < .05). RA + AP group exhibited a significantly higher level of TNF-α and a lower level of IL-2 compared to all other groups (p < .05). Both RA and RA + AP groups had significantly higher IL-17 levels (p < .05), while there was no significant difference in IL-1ß levels among the groups (p > .05). CONCLUSION: The findings from this study underscore a possible relationship between apical periodontitis and the exacerbation of rheumatoid arthritis.

Are CAD-CAM milled glass fiber posts better than prefabricated or custom glass fiber posts for endodontically treated teeth? A systematic review with meta-analysis.

STATEMENT OF PROBLEM: Prefabricated and custom glass fiber posts have been successfully used to reconstruct endodontically treated teeth. However, the performance of computer-aided design and computer-aided manufacture (CAD-CAM) milled glass fiber posts is unclear. PURPOSE: The purpose of this systematic review with meta-analysis was to compare the fracture and bond strength and cement layer thickness of CAD-CAM milled glass fiber posts with prefabricated or custom glass fiber posts. MATERIAL AND METHODS: The protocol was registered in the Open Science Framework (http://osf.io/65jm7). Two reviewers searched the PubMed/MEDLINE, Web of Science, Embase, Scopus, and ProQuest databases for articles up to September 2023. In addition, the reference lists were hand searched. A meta-analysis was performed by using the RevMan 5.4 program. The risk of bias was assessed using the RoBDEMAT tool. RESULTS: After screening, a total of 18 studies were included. The CAD-CAM milled glass fiber posts showed higher fracture strength (P=.02; Standardized Mean Difference [SMD]: 0.57; 95% Confidence Interval [CI]: 0.07 to 1.07), bond strength (P=.010; SMD: 1.07; 95% CI: 0.26 to 1.89), and lower cement layer thickness (P=.009; SMD: -2.94; 95% CI: -5.15 to -0.73) when compared with prefabricated glass fiber posts. However, fracture strength (P=.53; SMD: 0.38; 95% CI: -0.79 to 1.54) and bond strength (P=.90; SMD: -0.05; 95% CI: -0.81 to 0.72) were statistically similar between CAD-CAM milled and custom glass fiber posts. Significant and substantial heterogeneity was observed in all meta-analyzes (P<.01; I>60%). The studies sufficiently reported most domains related to bias, except for randomization of samples, sample size rationale and reporting and operator blinding. CONCLUSIONS: CAD-CAM milled and custom glass fiber posts provide an effective and safe option for restoring endodontically treated teeth, especially for weakened teeth or enlarged root canals. However, further well-designed clinical research is recommended to strengthen these findings.

Root canal dentin wear during final irrigation in endodontic retreatment with passive ultrasonic irrigation and easy clean instruments.

Context: Complementary procedures have been proposed to improve the endodontic retreatments. Aim: The aim of this study was to evaluate, by microcomputed tomography (micro-CT), the dentin wear caused by passive ultrasonic irrigation (PUI) and easy clean (EC) instruments, when used for the final removal of filling material during endodontic retreatment. Methods: Thirty-six mesial roots of the lower first molars were divided into four groups (n = 9), according to the final irrigation and sealer: PUI/AH Plus, EC/AH Plus, PUI/Total Fill (TF), and EC/TF. Canal volume was evaluated, both before and after the final irrigation, by micro-CT analysis. The Kruskal-Wallis test was used to compare the volumes among groups and the paired Wilcoxon test was used to compare the volume values before and after the final irrigation within each group. Results: Both complementary cleaning procedures promoted dentin wear that was observed only when the volume was analyzed for each third of the root canal. In the apical third, both instruments showed significant wear, where the use of the EC instrument resulted in greater wear than the PUI, in teeth filled with both AH Plus and TF BC Sealers (P < 0.05). Conclusion: Both complementary cleaning procedures promoted dentin wear and must be used cautiously.

Effects of increasing instrument size and taper on the disinfection and shaping of mandibular incisors.

This study assessed canal preparation effects on disinfection and dentin preservation. Thirty mandibular incisors were paired into two experimental groups (n = 10). Following contamination, the initial microbial sample was collected. Instruments 30/0.03 (Group 1) and 30/0.05 (Group 2) were employed and a second sample was obtained. Canals were enlarged using instruments 40/0.03 and 40/0.05, respectively, and a third sample was collected. Final irrigation was performed, and sample S4 obtained. A final scan evaluated volume, surface area, unprepared areas, removed dentin and dentin thickness. Data were analysed using Student t-test, Mann-Whitney, Kruskal-Wallis and Dunn tests. A significant difference was observed between S1 and other time points (p < 0.05). Comparison between groups showed no differences in bacterial loads and in the percentage of microbial reduction (p > 0.05). Group 2 exhibited greater reduction in dentin thickness than group 1 in the mesial aspect of the root (p < 0.05). Instrument 30/0.03 might provide effective disinfection and safety during mandibular incisors canal preparation.

Can the addition of surfactants to NaOCl irrigation impact on the percentage of voids of root canal filling?

This study evaluated the impact of canal irrigation using surfactants associated to NaOCl on the percentage of voids of root canal filling through micro-computed tomographic (micro-CT) analysis. 27 mandibular mesial roots with Vertucci type II canal configuration with isthmus were selected and scanned in a micro-CT device. The specimens were assigned to three groups (n = 9), according to the irrigation solution during instrumentation: 2.5% NaOCl without additives (control), 2.5% NaOCl with 0.1% Benzalkonium Chloride and 2.5% NaOCl with 0.1% Tween 80. After obturation, the specimens were rescanned, and the percentage of voids were calculated. Data were analysed using one-way ANOVA with a significance level of 5%. The percentage of voids were similar among the groups (p > 0.05). None of the specimens showed completely voids-free areas. The addition of surfactants to NaOCl irrigation did not improve the quality of root canal filling of mandibular mesial root canals.

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.

Effect of passive ultrasonic irrigation on hard tissue debris removal: a systematic review and meta-analysis

Abstract: Accumulated hard tissue debris (AHTD) in root canal irregularities may negatively impact adequate root canal disinfection. In light of this, the efficacy of passive ultrasonic irrigation (PUI) to reduce AHTD has been largely studied in in vitro studies, which have adopted different analytic methods of varying accuracy to determine the extent of AHTD more correctly. Therefore, the aim of this study was to compare how well PUI and non-activated irrigation (NAI) systems perform in reducing AHTD during final irrigation protocols, based exclusively on studies whose analyses used microCT scanning. A systematic search of the studies published up to April 2020 was performed using MeSH terms and free terms, in the following databases: PubMed, Scopus, Web of Science, BVS (Lilacs and BBO) and Embase. The inclusion criteria consisted of laboratory studies that evaluated the amount of AHTD, and compared PUI with NAI protocols using microCT analysis. The risk of bias in the selected studies was assessed critically by two reviewers. A meta-analysis was performed using the RevMan software program (P<0.05), and included studies providing the standardized mean difference (SMD), using a fixed effect model, and adopting a confidence interval of 95%. In all, 3495 studies were identified, three of which met the inclusion criteria. All three were considered as having a low risk of bias. The meta-analysis comparing the ability of PUI and NAI protocols to remove hard tissue debris showed a higher percentage of AHTD reduction (P<0.01) for PUI, with a confidence interval of 1.41 [0.79, 2.02]. The heterogeneity among the studies was 82% (I2). Considering the limitations of the present study, this systematic review and meta-analysis showed that PUI was more effective than NAI in removing hard tissue debris, based exclusively on studies that used microCT scanning to provide a more precise analysis of the two techniques used. The findings presented in the present study reinforce the concept that PUI can increase residue removal and improve the cleanliness of the root canal in endodontic treatments.

O uso da tomografia computadorizada de feixe cônico no diagnóstico e no gerenciamento de insucesso endodôntico: relato de caso clínico / The use of cone beam computed tomography in the diagnosis and management of endodontic failure: clinical case report

Objetivo: descrever um caso clínico em que a tomografia computadorizada de feixe cônico (TCFC) foi utilizada para auxiliar no diagnóstico e no melhor gerenciamento de retratamento endodôntico. Relato de caso: uma paciente compareceu à clínica com queixa de uma fístula na região dos molares superiores do lado direito há aproximadamente dois meses. Radiograficamente, observou-se lesão periapical do elemento 17. Após a confirmação da necessidade do retratamento, a paciente relatou já ter feito duas intervenções endodônticas nesse elemento. Assim, optou-se por solicitar um exame de TCFC, para melhores diagnóstico e planejamento do caso. Ao avaliar a TCFC, verificou-se presença de lesão periapical extensa, presença de espaços vazios no canal mesiovestibular (MV) e palatino (P), cone de guta percha além do ápice no canal distovestibular (DV) e localização do canal mesiopalatino (MP), que não havia sido manuseado anteriormente, rompimento de cortical óssea vestibular e palatino. Após planejamento, a paciente foi submetida ao retratamento endodôntico. Foi realizada a desobstrução dos canais radiculares com remoção do cone ultrapassando no canal DV, localização do MP e instrumentação completa de todos os canais. O hidróxido de cálcio foi utilizado como medicamento intracanal entre as consultas. Ao observar a regressão da fistula e os canais sem presença de exsudato, realizou-se a obturação do canal radicular. Considerações finais: a TCFC permitiu a visualização de erros operatórios pertinentes ao caso durante os tratamentos endodônticos prévios, o que possibilitou a indicação de um novo tratamento endodôntico e a manutenção do dente na arcada dentária.(AU)

Objective: to describe a clinical case where cone beam computed tomography (CBCT) was used to assist in the diagnosis and better management of endodontic retreatment. Case report: the patient attended the clinic complaining of a fistula in the upper molar region on the right side for approximately two months. Radiographically, the presence of a periapical lesion of element 17 was observed. After confirming the need for retreatment, the patient reported having already undergone two endodontic interventions on this tooth. Thus, it was decided to request a CBCT exam for better diagnosis and case planning. When assessing the CBCT, there was the presence of extensive periapical lesion, presence of empty spaces in the mesiobuccal (MB) and palatal (P) canal, gutta percha cone beyond the apex in the distobuccal (DB) canal and location of the mesiopalatal (MP) canal - which had not been previously handled -, rupture of the cortex vestibular and palatal bone. After planning, the patient underwent endodontic retreatment. Then, all the previous filling material were removed, including the gutta-percha by passing into the DB canal, MP was localized and complete instrumentation of all root canals were done. Calcium hydroxide was used as an intracanal medication between appointments. When the regression of the fistula was observed and canals were without exudate, root canal filling was performed. Final considerations: the CBCT allowed the visualization of operative errors pertinent to the case during previous endodontic treatments, which allowed the indication of a new endodontic treatment and the maintenance of the tooth in the dental arch.(AU)

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.

Capacidade de Adesão de Cimentos Biocerâmicos e Resinosos com a Dentina Radicular: Uma Revisão Integrativa / Adhesion capacity of bioceramic and resin-based root canal sealer to root dentin: an integrative review

Objetivo: comparar a capacidade de adesão do cimento biocerâmico EndoSequence BC e do cimento resinoso AH Plus através de uma revisão integrativa. Material e Métodos: os bancos de dados online Medline/PubMed, Scopus, Web of Science e BVS foram utilizados para a revisão da literatura. Os critérios de elegibilidade incluíram artigos disponíveis na íntegra nas bases de dados pesquisadas, em inglês, e o conteúdo referente à adesão do cimento Endosequence BC sealer em comparação ao AH Plus. Resultados: foram encontrados 45 artigos. Após a remoção duplicada, 22 artigos foram selecionados. Após a leitura dos resumos, textos completos e aplicação dos critérios de inclusão, foram incluídos no total oito artigos. Em relação à capacidade de adesão dos cimentos testados, o AH Plus apresentou melhor adesão do que o cimento BC sealer em três artigos e menor adesão em dois artigos. Força de adesão semelhante foi observada entre os grupos em três estudos. Conclusões: com base nos estudos incluídos, o AH Plus apresenta maior resistência de união quando comparado ao BC Sealer

Aim: To compare the adhesion capacity of the bioceramic EndoSequence BC sealer and the AH Plus sealer through an integrative review. Methodology: The Medline/PubMed, Scopus, Web of Science and VHL online databases were used for the literature review. Eligibility criteria comprised articles available in full on the researched databases, in English, and content addressing Endosequence BC sealer adhesion compared to AH Plus sealer. Results: A total of 45 articles were found. After duplicate removal, 22 articles were selected. After reading the abstracts, full texts and applying the inclusion criteria, eight articles in total were included in the present study. Concerning the adhesion capacity of the tested cements, the AH Plus was reported as presenting better adhesion than the BC sealer in three articles, and less adhesion in two articles. Similar adherence strength was observed between groups in three studies. Conclusions: Based on the included studies, the AH Plus displays greater bond strength when compared to the BC Sealer.

Efeito do consumo de álcool no desenvolvimento de lesão periapical induzida em ratos: uma análise microtomográfica / The Effect of Alcohol Consumption on the Development of Periapical Lesion Induced in Rats: a Micro-CT Analysis

Objetivo: O objetivo deste estudo foi avaliar a influência do consumo crônico de álcool no aumento da destruição óssea periapical em ratos. Material e métodos: Foram selecionados 12 ratos machos da linhagem Wistar, aleatoriamente divididos nos grupos controle e álcool (n=6). Os ratos do grupo álcool foram submetidos à auto-administração de solução alcoólica contendo 25% de álcool puro. O grupo controle recebeu apenas água filtrada durante o estudo. Após as 5 semanas de adaptação do grupo álcool, todos os ratos foram anestesiados e a polpa dos seus primeiros molares inferiores esquerdos foi exposta à cavidade oral para indução da lesão periapical. Após 28 dias de exposição pulpar, os ratos foram sacrificados por sobredose de anestesia, e suas mandíbulas foram removidas e seccionadas para avaliação microtomográfica. As hemimandíbulas esquerdas foram fixadas e escaneadas no microtomógrafo SkyScan 1173 (Bruker, Kontich, Belgium). O tamanho da lesão periradicular foi medido a partir das imagens de microtomografia computadorizada (micro-CT), onde foram calculados a área de superfície e o volume da lesão. Também foram avaliadas a taxa percentual de ganho de peso e a ingestão de sólidos/líquidos dos grupos. Os dados foram estatisticamente analisados utilizando o teste t de Student (p<0,05). Resultados: Os animais do grupo controle tiveram uma maior taxa percentual de ganho de peso corporal e de ingestão tanto de sólidos como de líquidos (p<0,05). As lesões periapicais apresentaram maior volume e maior área nos animais do grupo álcool, em comparação ao grupo controle (p<0,05). Conclusão: O consumo crônico de álcool contribuiu para o aumento da destruição óssea periapical em casos de periodontite apical.

Objective: the aim of this study was to evaluate the influence of alcohol consumption on the increase of periapical bone destruction in rats. Material and Methods: the sample included 12 Wistar male rats, randomly assigned into a control group and an alcohol group (n=6). Rats in the alcohol group were submitted to self-administration of a 25% pure alcoholic solution. The control group received only filtered water throughout the study. After 5 weeks of adaptation to the alcohol dose, all animals were anesthetized and the pulps of their mandibular left first molar were exposed to the oral cavity to induce periapical lesion. Twenty-eight days after the pulp exposure, those rats were euthanized due to overdose of anesthesia and their mandibles were removed and sectioned to obtain a micro-computed tomographic (micro-CT) scan. The rats' left hemimandibles were fixed and scanned on the SkyScan 1173 (Bruker, Konitch, Belgium) microtomograph. The size of the periradicular lesions was measured from the images obtained on the micro-CT and the surface area and volume were calculated. It was also evaluated the weight gain rate and the ingestion of solid/liquid of both groups. Data were analyzed by the Student's t-test (p<0.05). Results: the control group showed higher rates of weight gain and ingested more solid and liquid than the alcohol group (p<0.05). Periapical lesions found in the alcohol group had higher volume and surface area than the ones of the control group (p<0.05). Conclusion: the chronic consumption of alcohol contributed to the increase of periapical bone destruction in cases of apical periodontitis

Extrusão apical de debris após o uso de um instrumento reciprocante e uso suplementar de instrumento com liga MaxWire / Apically Extruded Debris Using Reciprocating Single File and Additional Use of MaxWire Allow File

Objetivo: O objetivo deste estudo foi avaliar a quantidade de debris extruídos apicalmente após o preparo do canal com o WaveOne Gold e o uso suplementar do instrumento XP-Endo Finisher. Material e Métodos: Quarenta pré-molares humanos com canal único foram selecionados e divididos em dois grupos (n = 20): preparo com instrumento WaveOne Gold e preparo com instrumento WaveOne Gold + XP-Endo Finisher. Os canais radiculares foram instrumentados seguindo as instruções do fabricante e a água destilada foi usada como irrigante. Debris extruídos apicalmente durante a instrumentação foram coletados em tubos Eppendorf pesados previamente em balança analítico. O peso dos detritos extruídos foi estabelecido subtraindo-se o peso pré-instrumentação e pós-instrumentação dos tubos Eppendorf para cada grupo. Resultados: Os dados foram analisados pelos testes de Shapiro-Wilk e Mann-Whitney, com nível de significância de 5%. Não houve diferença significativa entre os grupos (p = 0,66) em relação à quantidade debris extruídos apicalmente. Conclusão: A presença de debris extruídos apicalmente ocorreu nos dois grupos; no entanto, o uso adicional do instrumento XP-Endo Finisher não contribuiu para o aumento significativo da extrusão apical de detritos quando comparado ao uso isolado do instrumento WaveOne Gold.

Objective: the aim of this study was to evaluate the amount of apically extruded debris after the preparation with WaveOne Gold and additional use of XP-Endo Finisher file. Material and Methods: Forty human one-rooted premolars were selected and divided into two groups (n=20): WaveOne Gold and WaveOne Gold and XP-Endo finisher. Subsequently, the root canals were instrumented following the manufacturer's instructions and distilled water was used as irrigant. Apically extruded debris during instrumentation was collected into pre-weighed Eppendorf tubes. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and postinstrumentation weight of the Eppendorf tubes for each group. Results: The data were analyzed using Shapiro-Wilk and Mann-Whitney tests, with significant level of 5%. There was no significant difference between groups (p=0.66) in relation to apically extruded debris. Conclusion: apically extruded debris occurred in both groups; however, the additional use of the XP-Endo Finisher instrument did not contribute to the significant increase of apical extrusion of debris when compared to the isolated use of WaveOne Gold

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

Effect of a sonic device on bonding of fiberglass posts to root canals

Aim: This study evaluated the effect of a sonic device on the bonding of fiberglass posts cemented with a self-etching adhesive combined with conventional cement or a self-adhesive cement to root dentin. Methods: Forty single-rooted bovine incisors were endodontically prepared using a step-back technique. Gutta-percha and AH Plus sealer were used for root canal filling, combined with a thermoplasticization technique. After 1 week, the post space was prepared and the roots were divided into four groups according to the following factors: adhesive system/resin cement (Ambar/ AllCem Core [FGM] and RelyX U200 [3M]) and application mode (manual or sonic). The posts were cemented and the roots were cut into discs and submitted to push-out bond strength (POBS) test. The failure mode was evaluated using a stereoscope at 25x magnification. The data were analyzed statistically using ANOVA and Tukey's post-hoc test (α = 0.05). Results: The sonically activated RelyX U200 group was superior to the other groups. RelyX U200 manually applicated showed similar results to those of sonically activated Âmbar/AllCem. These three groups outperformed the Âmbar/AllCem manually applicated group. Adhesive failure between dentin and resin cement was the most predominant pattern. Conclusion: Sonic application of self-etching adhesive and self-adhesive cement improved the POBS of fiber posts to the root canal

Estratégias minimamente invasivas de acesso e preparo e os diferentes desfechos na terapia endodôntica / Minimally invasive access and root canal preparation strategies and the different outcomes in endodontic therapy

As cavidades de acesso dominaram a recente discussão sobre a Endodontia minimamente invasiva (EMI). No entanto, a rotulagem da EMI é mais ampla, envolvendo o uso de instrumentos com conicidades reduzidas ou geometrias inovadoras que permitam a remoção mínima de dentina. Além disso, aprimoramentos metodológicos têm sido sugeridos para mimetizar condições clínicas. Buscando responder algumas questões acerca da EMI, a presente tese é dividida em dois estudos. O estudo 1 avaliou a influência do acesso ultraconservador (UltraAC) na instrumentação, na qualidade da obturação e na capacidade máxima de carga para fratura em molares inferiores após o preparo do canal com o sistema XP-endo Shaper (XP) ou Reciproc (RC) em condições clínicas simuladas. Para isso, quarenta molares inferiores foram microtomografados e pareados em quatro grupos (n = 10), de acordo com o acesso e a instrumentação: TradAC/RC, TradAC/XP, UltraAC/RC e UltraAC/XP. Os dentes foram reescaneados e os parâmetros da instrumentação e obturação foram analisados. Os dentes foram restaurados e submetidos à ciclagem termomecânica e à capacidade máxima de carga para a fratura. O teste ANOVA foi usado para a análise estatística (P < 0,05). Os grupos TradAC apresentaram menor porcentagem (%) de área não preparada do que os grupos UltraAC (P < 0,05). O grupo UltraAC/XP apresentou a menor % de dentina removida (P < 0,05). A % de debris foi menor nos grupos UltraAC/XP e TradAC/XP do que no UltraAC/RC e TradAC/RC (P < 0,05). Os grupos UltraAC demonstraram maior % de espaços vazios e de material obturador na câmara pulpar (P < 0,05). Não houve diferença na capacidade máxima de carga para a fratura entre os grupos (P > 0,05). O estudo 2 avaliou o uso de instrumentos com conicidade reduzida - Bassi Logic ,03 (BL), com diferentes designs (XP) e como grupo de comparação o sistem Reciproc, na eficácia da instrumentação dos canais em condições clínicas simuladas. Vinte e quatro molares foram microtomografados, acessados de forma tradicional e divididos em três grupos (n = 8), de acordo com o preparo: BL, XP e RC. Nos grupos BL e RC, os canais mesiais foram instrumentados com 25/,03 ou R25 e o canal distal com 25/,03 e 40/,03 ou R25 e R40, respectivamente. No grupo XP, o mesmo instrumento foi utilizado em todos os canais (30/,04). Após o preparo, os dentes foram reescaneados e a % de área não preparada e de dentina removida foram avaliadas separadamente para os canais mesiais e distal. Os dados foram analisados com os testes ANOVA e de Tukey (P < 0,05). Verificou-se que o grupo BL apresentou maior % de área não preparada para ambos os canais em relação aos grupos XP e RC (P < 0,05). No entanto, não houve diferença na % de dentina removida entre os grupos (P > 0,05). Com base nos estudos, conclui-se que as estratégias minimamente invasivas adotadas no acesso e na instrumentação foram desvantajosas frente a tratamentos tradicionais, não justificando o seu uso(AU)

Access cavities have dominated the recent discussion on minimally invasive Endodontics (EMI). However, the issue of MIE is broader than access cavities, such as the use of instruments with reduced taper or innovative geometries that allow minimal dentin removal. Furthermore, methodological improvements have been suggested to mimic clinical conditions. Seeking to answer some questions about EMI, this thesis is divided into two studies. The first study evaluated the influence of ultraconservative access (UltraAC) on canal shaping, filling ability and maximum load capacity for fracture of mandibular molars after root canal preparation with XP-endo Shaper (XP) or Reciproc (RC), under simulated clinical conditions. Thus, forty mandibular molars were scanned and paired into four groups (n = 10), according to access and instrumentation protocol: TradAC/RC, TradAC/XP, UltraAC/RC and UltraAC/XP. Teeth were rescanned and the instrumentation and filling parameters were analyzed. The teeth were restored and submitted to thermomechanical cycling and maximum load capacity for the fracture. ANOVA test was used for statistical analysis (P < 0.05). The TradAC groups had a lower percentage (%) of unprepared area than the UltraAC groups (P < 0.05). The UltraAC/XP group had the lowest % of dentin removed (P < 0.05). The % of debris was lower in the UltraAC/XP and TradAC/XP groups than in the UltraAC/RC and TradAC/RC groups (P < 0.05). The highest % of voids and filling material in the pulp chamber was observed in the UltraAC groups (P < 0.05). There was no difference in the maximum load capacity for the fracture between the groups (P > 0.05). The second study evaluated the use of a reduced taper endodontic instrument system - Bassi Logic .03 taper (BL), expandable heat-treated system (XP) and, as comparison, the Reciproc system, on the ability to shape canals under simulated clinical conditions. For that, twenty-four mandibular molars were scanned and divided into three groups (n = 8), according to root canal instrumentation system: BL, XP and RC. In the BL and RC groups, the mesial canals were instrumented with 25/.03 or R25 and the distal canal with 25/.03 and 40/.03 or R25 and R40, respectively. In the XP group, the same instrument was used in all root canals (30/.04). After preparation, the teeth were rescanned and the % of unprepared area and dentin removed were evaluated separately for the mesial and distal canals. Data were analyzed using ANOVA and Tukey tests (P < 0.05). It was found that the BL group had a higher % of unprepared area for both root canals compared to the XP and RC groups (P < 0.05). However, there was no difference in the % of dentin removed between groups (P > 0.05). Based on the studies, it is concluded that there is no justification for the use of EMI since in general, UltraAC did not promote advantages over TradAC and the use of instruments with reduced taper resulted in a larger unprepared area, which could possibly influence the cleaning of the root canal system (AU)

Effect of Argon Plasma on Root Dentin after Use of 6% NaOCl

Abstract The aim of this study was to evaluate the effect of argon plasma on dentin surface after use of 6% NaOCl. Sixty bovine incisors had their crowns removed, the roots split, and the segments planed. One hundred twenty segments of the cervical third were used. The samples were divided in two groups (n=60): Control group: immersed in 6% NaOCl, washed, dried and then immersed in 17% EDTA, washed and dried and Argon group: after treatment described for the Control group, non-thermal argon plasma was applied for 30 s. Ten samples were evaluated by scanning electron microscopy in each group. Other ten samples were analyzed by Fourier transform infrared spectroscopy (FTIR). Thirty samples were analyzed with a goniometer to measure the contact angle between the dentin surfaces and solutions, to determine the surface free energy. The last ten samples were used to evaluate the wettability of AH Plus sealer. Data were statistically analyzed using Kruskal Wallis and Mann-Whitney tests (p<0.05). The results of this study showed that argon plasma did not modify the surface topography. FTIR analysis showed chemical modifications after plasma treatment. Argon plasma increased the surface free energy of dentin and AH Plus wettability. In conclusion, argon plasma treatment modified chemically the dentin surface. This treatment increased the surface free energy and wettability of an epoxy resin root canal sealer, favoring its bonding to dentin surfaces.

Resumo O objetivo do presente estudo foi avaliar o efeito do plasma de argônio na superfície dentinária após o uso de NaOCl 6%. As coroas de 60 incisivos bovinos foram removidas, as raízes clivadas e os segmentos planificados. Cento e vinte segmentos referentes ao terço cervical foram utilizados. As amostras foram divididas em dois grupos (n=60): Grupo Controle: imersos em NaOCl 6%, lavados, secos, imersos em EDTA 17%, lavados e secos e Grupo Argônio: após o tratamento descrito no grupo controle, foi aplicado plasma de argônio não térmico por 30 s. Em cada grupo, 10 amostras foram avaliadas por microscopia eletrônica de varredura. Outras dez amostras foram analisadas por espectroscopia no infravermelho por transformada de Fourier (FTIR). Trinta amostras foram analisadas com um goniômetro para medir o ângulo de contato entre a superfície dentinária e as soluções e determinar a energia livre de superfície. As últimas dez amostras foram utilizadas para avaliar a molhabilidade do cimento AH Plus. Os dados foram analisados estatisticamente usando os testes de Kruskal Wallis e Mann-Whitney (p<0,05). Os resultados do estudo mostraram que o plasma de argônio não modificou a topografia de superfície. A análise por FTIR mostrou modificações químicas após o tratamento de plasma. O plasma de argônio aumentou a energia livre da superfície dentinária e a molhabilidade do cimento AH Plus. Conclusão, o tratamento com plasma de argônio modificou quimicamente a superfície dentinária. Este tratamento aumentou a energia livre de superfície e a molhabilidade de um cimento endodôntico à base de resina epóxi, favorecendo as características adesivas da superfície dentinária.

Evaluation of the dentin changes in teeth subjected to endodontic treatment and photodynamic therapy / Avaliação das alterações morfológicas de dentes submetidos ao tratamento endodôntico e a terapia fotodinâmica

Introduction: Antimicrobial photodynamic therapy (PDT) is an efficient adjuvant technique to promote disinfection of the root canal system. Therefore, it is important to investigate changes to dentin morphology and permeability induced by the use of diode laser on the root dentin. Objective: The purpose of this study was to investigate morphological changes and the percentage of apical leakage after the use of laser. Material and method: Forty single-rooted teeth were instrumented using rotary system and irrigated. Teeth were randomly divided in two groups: G1 - not exposed to PDT (control), and G2 - pretreated with toluidine blue photosensitizer and irradiated with AsGaAl laser diode. Ten teeth in each group were evaluated by SEM for morphological changes. The other ten teeth were filled and stained with Rhodamine B to evaluate the apical leakage. Result: The results showed significant difference between G1 and G2 (p< 0.001 - chi-square), with greater presence of debris in G1 and higher incidence of open dentinal tubules in G2. Erosions and cracks were observed in both groups, with no statistically significant difference (p> 0.001). The apical leakage was significantly higher in G2 than in G1 (p< 0.001 - Student's t-test). Conclusion: It was concluded that the use of low-level laser reduced the smear layer and opened the dentinal tubules. Use of laser increased the permeability of the apical dentin.

Resumo Introdução A PDT antimicrobiana é um eficiente método coadjuvante na desinfecção do sistema de canais radiculares, o que torna importante o estudo sobre a possibilidade de alterações morfológicas e permeabilidade provocadas pelo laser de diodo na estrutura dentinária radicular. Objetivo A proposta deste estudo foi investigar as alterações morfológicas e percentual de infiltração apical radicular após o uso do laser diodo. Material e método Quarenta dentes monorradiculares foram instrumentados pelo sistema rotatório Protaper e irrigados com NaOCl 5,25% e EDTA 17%. Depois, foram divididos aleatoriamente em: G1: não receberam PDT (controle); G2: receberam pré-irradiação com fotossensibilizador azul de toluidina e irradiação com laser diodo de AsGaAl. Em seguida, 10 dentes de cada grupo foram analisados por MEV quanto as alterações morfológicas. Os outros 10 dentes foram obturados e corados por Rodamina B para avaliar o percentual de infiltração apical. Resultado Os resultados mostraram diferença significativa entre G1 e G2 (p< 0,001 - qui-quadrado), verificando maior presença de debris em G1 (controle) e maior ocorrência de túbulos dentinários abertos em G2 (PDT). Erosões e cracks foram observadas em ambos os grupos, sem diferença estatística significativa (p> 0,001). O percentual de infiltração apical foi significativamente maior em G2 que em G1 (p< 0,001 - t student). Conclusão Concluiu-se que a utilização do laser diodo promoveu a redução de smear layer e abertura dos túbulos dentinários, não influenciando na ocorrência de erosão, cracks e carbonização. O laser aumentou a permeabilidade da dentina apical.

Influência do pré-alargamento coronário na resistência à fadiga cíclica de instrumentos reciprocantes tratados termicamente / Influence of coronal pre-enlargement on cyclic fatigue resistance of heat-treated reciprocating instruments

Objetivo: O objetivo do presente estudo foi avaliar a influência do pré-alargamento coronário na resistência à fadiga cíclica de dois instrumentos reciprocantes tratados termicamente. Métodos: 20 instrumentos Reciproc Blue (R25 Blue) e 20 instrumentos X1 Blue (X1) foram utilizados para instrumentar blocos de resina simulando um molar superior com três canais radiculares. Os dentes foram divididos em quatro grupos (n=10), de acordo com o instrumento e com a técnica de instrumentação utilizada: grupos R25 e X1 - instrumentação com R25 Blue (25/0.08) ou X1 Blue (25/0.06), respectivamente, sem alargamento prévio; e grupos R25 ou X1 + pré-alargamento cervical - pré-alargamento com os instrumentos ProTaper Universal SX e S1 antes da instrumentação com R25 Blue ou X1. Os instrumentos foram testados com relação à fadiga cíclica utilizando-se um canal simulado de aço inoxidável com ângulo de curvatura de 86 graus e raio de curvatura de 6 mm. Os instrumentos foram acionados utilizando-se o movimento "RECIPROC ALL" do motor endodôntico (VDW) e o tempo de instrumentação até a fratura do instrumento foi contabilizado. Os resultados foram analisados pelo teste t de Student (p<0,05). Resultados: Os instrumentos X1 apresentaram maior resistência à fadiga cíclica do que R25 Blue em ambas as condições testadas (p<0,05). Não houve diferença entre os grupos com e sem pré-alargamento coronário para os instrumentos R25 Blue e X1 (p>0,05). Conclusão: O instrumento X1 Blue apresentou maior resistência à fadiga cíclica do que o Reciproc Blue. O pré-alargamento coronário não foi capaz de aumentar a resistência à fratura por fadiga cíclica dos instrumentos testados (AU).

Objective: The aim of this study was to evaluate the influence of cervical pre-flaring on the cyclic fatigue resistance of two heat-treated reciprocating instruments. Methods: 20 Reciproc Blue (R25 Blue) instruments e 20 X1 Blue File (X1) were used to instrument resin blocks simulating an upper molar with 3 root canals. The specimens were divided into four groups (n=10) according the instrument and type of instrumentation used: R25 and X1 groups: root canal preparation with R25 Blue (25/0.08) ou X1 Blue (25/0.06), without cervical pre-flaring; R25 or X1 + cervical pre-flaring- pre-flaring with ProTaper Universal SX e S1 before instrumentation with R25 Blue or X1 blue. After instrumentation the instruments were tested for cyclic fatigue using a simulated stainless steel root canal with 86 degree bending angle and 6 mm bending radius. The instruments were triggered using the "RECIPROC ALL" motion of a reciprocating endodontic motor (VDW) and the instrumentation time until instrument fracture was accounted. Results were analyzed by Students t-test (p<0.05). Results: Statistical analysis showed that the X1 Blue showed higher resistance to cyclic fatigue than the R25 Blue under both conditions tested (p<0.05). There were no differences between the groups with and without coronary pre-flaring for the R25 Blue and X1 Blue (p<0.05). Conclusion: X1 Blue showed higher resistance to cyclic fatigue than the R25 Blue. The cervical pre-flaring did not increased the resistance to cyclic fatigue fracture of the tested instruments (AU)

Efeito de agentes dessensibilizantes na obliteração dos túbulos dentinários - estudo in vitro / Effect of desensitizing agents for dentinal tubules obliteration - in vitro study

Objetivo: avaliar o número de aplicações necessárias para a completa obliteração dos túbulos dentinários utilizando diferentes agentes dessensibilizantes. Material e Métodos: a porção do esmalte coronário da face vestibular de 40 incisivos bovinos foi removida com auxílio de lixas para expor a dentina superficial da junção amelo-cementária. Em seguida, as raízes e a porção coronária referente ao terço médio-incisal dos dentes foram removidas. A seguir foi realizada a completa remoção de smear layer, evidenciando os túbulos dentinários. As amostras foram divididas em quatro grupos experimentais conforme o agente dessensibilizante utilizado: verniz fluoretado, adesivo dentinário, dessensibilizante dentinário e creme dental. Os produtos foram aplicados de acordo com as recomendações do fabricante. As amostras foram avaliadas previamente e após o uso dos agentes por microscopia eletrônica de varredura de baixo vácuo. A aplicação do agente e a análise foram realizadas até a completa obliteração dos túbulos dentinários. Os dados foram avaliados estatisticamente em relação ao número de aplicações necessárias utilizando os testes de Kruskal-Wallis e Mann-Whitney (p < 0,05). Resultados: o verniz fluoretado foi o mais eficaz dos agentes avaliados, sendo necessária uma aplicação para a completa obliteração dos túbulos. Para o adesivo dentinário foram necessárias duas aplicações e para o dessensibilizante e o creme dental foram necessárias cinco aplicações. Conclusão: os agentes dessensibilizantes testados necessitam de um número variado de aplicações, sendo o mais eficaz o verniz fluoretado, onde apenas uma aplicação possibilitou a completa obliteração dos túbulos.

Objective: The aim of this study was to evaluate the number of applications necessary for the complete obliteration of dentinal tubules using different desensitizing agents. Materials and Methods: A portion of coronary enamel of the buccal surface of 40 bovine incisors was removed with the aid of sandpaper in order to expose the superficial dentin at the dentin-enamel junction. The roots and the coronary portions of the mesial-incisal third of the teeth were also removed. Complete smear-layer removal was performed, exposing the dentinal tubules. Samples were divided into four experimental groups according to the desensitizing agents used: fluoride varnish; dentin adhesive; dentin desensitizing; and toothpaste. The products were applied in accordance with the manufacturer's recommendations. Samples were evaluated before and after the application of different agents by scanning electronic microscopy of low vacuum. The application of the products and analyses were carried out until complete obliteration of dentinal tubules. Data were evaluated statistically in relation to the required number of applications, using Kruskal-Wallis and Mann-Whitney tests (p < 0.05). Results: The results showed that fluoride varnish was the most efficient of the tested agents, requiring a single application for the complete obliteration of the dentinal tubule. For the dentin adhesive, two applications were necessary and for the dentin desensitizing and toothpaste, five applications were required. Conclusion: The desensitizing agents tested required a distinct number of applications, and the fluoride varnish was the most effective agent, with a single application resulting in the complete obliteration of the dentin tubule.

Acessos endodônticos: o que todo endodontista deve saber / Endodontic accesses: what every endodontist should know

Introdução: Os acessos endodônticos minimamente invasivos (AEMI) surgiram com o intuito de, por meio da preservação de estrutura dentária, manter a resistência à fratura de dentes tratados endodonticamente. A partir do primeiro estudo, em 2010, vários trabalhos foram desenvolvidos buscando entender qual a influência dos AEMI na resistência à fratura de dentes tratados endodonticamente. No entanto, interferências coronárias causadas pelos AEMI poderiam prejudicar a realização dos procedimentos subsequentes à cavidade de acesso, como a localização, instrumentação, limpeza, descontaminação e obturação dos canais radiculares. Objetivo: Com base nessa premissa, a presente revisão teve como objetivo responder algumas perguntas para que o clínico entenda quais são as principais modalidades de AEMI, os impactos da sua abordagem no tratamento endodôntico e o verdadeiro papel do tratamento endodôntico na perda dos elementos dentários. Resultados: Considerando os dados disponíveis até o presente momento, faltam evidências robustas para apoiar a alegação de que os AEMIs preservem a resistência à fratura dos elementos tratados endodonticamente melhor do que nos dentes acessados de maneira tradicional. Além disso, cavidades de acesso minimamente invasivas podem interferir em outras etapas do tratamento endodôntico, podendo torná-lo imprevisível. Conclusão: Dessa forma, pode-se concluir que há uma falta de evidências que apoiem a utilização de cavidades de acesso minimamente invasivas na prática clínica de rotina e/ou no processo de formação de alunos de graduação e pós-graduação (AU).

Introduction: Minimally invasive access cavities emerged aiming to maintain the fracture resistance of endodontically treated teeth through the preservation of dental structure. Starting with the first study in 2010, several others were developed to evaluate the influence of minimally invasive access cavities in the fracture resistance of endodontically treated teeth. However, the coronal interference caused by those access cavities could impair the subsequent procedures of root canal treatment, such as the location, instrumentation, cleaning, disinfection and filling of the root canals. Objective: Based on this premise, the aim of the present review was to answer some questions so that the clinician knows the main modalities of minimally invasive access cavities, the impacts of this approach and the real role of endodontic treatment in the tooth loss. Results: Considering the available data, there is a lack of robust evidence in literature to support the claim that the minimally invasive access cavities preserve the fracture resistance of endodontically treated teeth better than the traditional one. In addition, these access cavities can interfere in other stages of endodontic treatment, making it unpredictable. Conclusion: Thus, it can be concluded that there is a lack of evidence to support the use of minimally invasive access cavities in routine clinical practice and/or in the process of training undergraduate and graduate students (AU).