Percepção profissional sobre tratamento endodôntico em sessão única e múltiplas sessões / Professional perception of single and multi-session endodontic treatment

Na odontologia a decisão do tratamento é exclusiva dos cirurgiões dentistas e suas percepções, incluindo filosofia de tratamento, fazendo com que a prática de novos conceitos, tratamentos ou técnicas dependam não apenas de sua lógica ou eficácia biológica. Sendo assim, este estudo teve como objetivo avaliar os parâmetros envolvidos na tomada de decisão de cirurgiões dentistas clínicos e especialistas para a realização do tratamento endodôntico em sessão única ou múltiplas sessões. Para tanto, este estudo contou com uma coleta de dados através de um questionário online, aplicado cirurgiões dentistas clínicos gerais e especialistas em endodontia. As respostas foram tabuladas e analisadas por meio de estatística descritiva. Os resultados revelaram que a maioria dos endodontistas e dos clínicos gerais prefere realizar tratamento endodôntico em sessão única, devido ao menor desperdício de material, além do melhor domínio da anatomia e tratamento em um único momento. O motivo mais comum para os endodontistas e clínicos gerais escolherem o tratamento com múltiplas visitas é para dentes com prognóstico duvidoso e os casos em que o profissional aguarda a remissão dos sintomas antes da obturação. Em conclusão, a maioria dos endodontistas e dos clínicos gerais preferiu realizar tratamento endodôntico em sessão única.

In dentistry, treatment decisions are made exclusively by dental surgeons and their perceptions, including treatment philosophy, which means that the practice of new concepts, treatments or techniques depends not only on their logic or biological efficacy. Therefore, the aim of this study was to evaluate the parameters involved in clinical and specialist dental surgeons' decision to carry out endodontic treatment in single or multiple sessions. To this end, data was collected using an online questionnaire administered to general dental surgeons and endodontic specialists. The answers were tabulated and analyzed using descriptive statistics. The results revealed that the majority of endodontists and general practitioners prefer to carry out endodontic treatment in a single session, due to less wastage of material, as well as better mastery of the anatomy and treatment at a single time. The most common reason for endodontists and general practitioners to choose treatment with multiple visits is for teeth with a doubtful prognosis and cases in which the professional is waiting for symptoms to remit before filling. In conclusion, the majority of endodontists and general practitioners preferred to carry out endodontic treatment in a single session.

Nonsurgical Endodontic Treatment of Type II Dens Invaginatus in A Maxillary Lateral Incisor: A Case Report.

Dens invaginatus (DI) is one of the developmental dental anomalies that results in an invagination of the enamel organ into the dental papila during odontogenesis. The purpose of this study is to report a case of nonsurgical endodontic treatment of an Oehlers type II DI in a right maxillary lateral incisor with an extensive periapical damage, along with the two-year clinical and tomographic follow-up. A 30-year-old patient was referred for endodontic treatment of tooth #12. On clinical examination, a change in the shape and color of the crown was observed. The tooth responded negative to pulp sensibility, percussion, palpation and mobility tests. After tomographic evaluation, an Oehlers type II DI was visualized, in addition to an extensive periradicular lesion. The diagnosis was asymptomatic apical periodontitis. The treatment was carried out in two sessions, through intense enhancement of the auxiliary chemical substance with passive ultrasonic irrigation, XP-Endo Finisher and the use of hydroxide-based intracanal medication. Appropriate treatment in cases with anatomic variations requires an accurate and early diagnosis based on clinical examination and radiographic images. A two-year follow-up of the present case showed that the correct diagnosis associated with appropriate instrumentation techniques, supplementary disinfection, and adequate three-dimensional sealing of the canal with filling material, resulted in regression of the periradicular lesion and bone repair.

Effect of pomegranate solution alone or combined with chlorhexidine against oral multispecies biofilm.

AIM: Natural bioactive products have been tested as alternative antimicrobial agents. This study evaluated the effect of Punica granatum extract (PGE) on oral multispecies biofilms. METHODOLOGY: Lyophilized extracts from pomegranate peel were prepared, and the punicalagin content was assessed by ultra-performance liquid chromatography (UPLC). Oral multispecies biofilms from 2 donors were grown on four collagen-coated hydroxyapatite discs. After incubation for 7 days or 3 weeks, the biofilms were exposed to water (control), 2% CHX, 10% PGE, 20% PGE or 30% PGE for 3 min. The proportions of dead bacteria were assessed by the live/dead staining and confocal microscopy. After the analysis, the best PGE concentration (30%) was combined with CHX. The experimental phases were repeated using water, 2% CHX, 30% PGE and 30% PGE + 2% CHX. Five random areas of the biofilm on each disc were scanned, resulting in 20 scanned areas for each group. RESULTS: Regarding the biofilm volume, no differences were found amongst solutions (p = .111). The PGE solution killed bacteria effectively in 1-week, 2-week and 3-week-old-plaque biofilms, ranging from 37 to 55.3%, depending on the PGE concentration. The 30% PGE (a) (p = .0009) had greater antibiofilm effectiveness than 2% CHX (b), which killed bacteria in the 25.2 to 48.7% range. The 10% and 20% PGE had intermediate values (ab), without significant differences from 30% PGE (p = 1.002). Water (c) had the lowest proportion of dead bacteria (p < .00001) in a range of 5 to 6.7% and lower effectiveness in killing bacteria (p < .05). The PGE alone or mixed with 2% CHX had greater anti-biofilm effectiveness than CHX (p < .05). The old plaque biofilms were more resistant than the 7-day-old plaque (p < .05). CONCLUSIONS: The 30% PGE (alone or combined with CHX) exhibited a greater antibiofilm effect on oral multispecies biofilms grown on hydroxyapatite discs than 2% CHX.

Efficacy of preoperative and postoperative medications in reducing pain after non-surgical root canal treatment: an umbrella review.

OBJECTIVE: This study analyzed, using an umbrella review, existing systematic reviews on medications to prevent and control postoperative endodontic pain to guide professionals in choosing the most effective drug. MATERIALS AND METHODS: An electronic search in the PubMed (MEDLINE), LILACS, SciELO, EMBASE, Scopus, Web of Science, Cochrane Reviews, and Data Archiving and Networked Services (DANS) databases retrieved 17 systematic reviews. The study included only systematic reviews of clinical trials with or without meta-analyses evaluating effectiveness of medications in reducing pain after non-surgical endodontic treatment. RESULTS: The evidence showed that steroidal and non-steroidal anti-inflammatory drugs and opioids effectively controlled pain within six to 24 h. CONCLUSIONS: Dexamethasone, prednisolone, paracetamol, and mainly ibuprofen provided higher postoperative pain relief. The quality of evidence of the reviews ranged from very low to high, and the risk of bias from low to high, suggesting the need for well-designed clinical trials to provide confirmatory evidence. CLINICAL RELEVANCE: This review emphasizes the efficacy of developing protocols for pain control after endodontic therapy.

Effect of radiotherapy, immediate dentin sealing and irrigation simulating single- or two-visits endodontic treatment on the bond strength to pulp chamber dentin: an in vitro study.

This study aimed to evaluate the influence of radiotherapy and different endodontic treatment protocols on the bond strength to pulp chamber dentin. Eighty mandibular molars were randomly divided into two groups (n = 40): non-irradiated and irradiated (60 Gy). The pulp chambers were sectioned, and each group was subdivided (n = 8), according to the endodontic treatment protocol: no treatment (Control); Single-visit; Two-visits; Immediate dentin sealing (IDS) + single-visit; and IDS + two-visits. Each endodontic treatment visit was simulated through irrigation with 2.5% NaOCl, 17% EDTA and distilled water. IDS was performed by actively applying two coats of a universal adhesive to the lateral walls of the pulp chamber. After, the pulp chambers were restored with resin composite and four sticks were obtained for microtensile test. In addition, the dentin of the pulp chamber roof was assessed for surface roughness, chemical composition, and topography after each treatment protocol. Two-way ANOVA, Tukey's post hoc, Mann-Whitney, Kruskal-Wallis and Dunn's post hoc were performed (α = 5%). The treatment protocol affected bond strength (p < 0.05), while the irradiation did not (p > 0.05). The control group presented the highest values (p < 0.05). The single-visit group demonstrated better performance compared to the other groups (p < 0.05), which did not differ from each other (p > 0.05) The use of IDS changed the surface roughness (p < 0.05), chemical composition (p < 0.05) and topography of the dentin. In conclusion, the treatment protocol influenced dentin adhesion, while irradiation did not.

Prevalence and Classification of C-Shaped Canal and Radix in Mandibular Molars Using Cone-Beam Computed Tomography on Mexican Population.

The diverse morphological configurations in teeth present clinical challenges in root canal treatment, complicating instrumentation and irrigation processes, which can lead to treatment failure. Understanding anatomical variations, such as C-shaped canals and radix entomolaris, enhances clinical skills and improves long-term endodontic treatment success rates. Cone-beam computed tomography (CBCT) offers superior diagnostic capabilities over conventional radiography, enabling the pre-operative detection of root configurations and canal numbers, facilitating personalized endodontic treatments. A total of 2173 teeth of a Mexican population, including 1057 first mandibular molars and 1116 s mandibular molars, were studied using only CBCT to identify C-shaped canals and radix configurations of patients who were treated from 2018 to 2023 at the Department of Radiology at the Faculty of Dentistry, Juarez University of the State of Durango, Mexico. C-shaped canals were identified in 160 teeth, with a prevalence of 0.2% in first mandibular molars and 14.1% in second mandibular molars. The highest frequency was in the left second mandibular molar (3.7) at 14.8%. Gender differences were significant, with higher prevalence in females (27.3%) compared to males (13.3%). The most common C-shaped canal configuration was type C2 (39.3%). Radix entomolaris was found in 52 teeth, with a prevalence of 3.4% in first mandibular molars and 1.4% in second mandibular molars. This research on a Mexican population using cone-beam computed tomography (CBCT) highlights significant findings in the prevalence and types of C-shaped canals and radix entomolaris in mandibular molars for this population. The left second mandibular molar (3.7) showed the highest prevalence at 14.8%, followed closely by the right second mandibular molar (4.7) at 13.5%, with a significant difference (p < 0.001). We found a significant difference in the prevalence of C-shaped canals between genders (p = 0.004, OR 1.78). Additionally, radix entomolaris (p < 0.001) was more frequently identified in first mandibular molars to a significant degree. These insights underscore the importance of CBCT in diagnosing complex root anatomies, which can greatly enhance the success rates of endodontic procedures by allowing for more tailored and precise treatments for this population.

Morphology of the Second Mesiobuccal Canal in the Maxillary Second Molar / Morfología del Segundo Canal Mesiovestibular en el Segundo Molar Maxilar

SUMMARY: Failure to locate a complete canal system affects the prognosis of root canal treatment. A missed root canal is one of the most common reasons for failed root canal treatment. The prevalence of the second mesiobuccal canal in the maxillary second molar is relatively high and has a variety of configurations. Therefore, knowledge of its morphology is required in clinical endodontics. This review presented the canal in terms of its prevalence, classification, anatomical features, and the method for locating the second mesiobuccal canal in the maxillary second molar. Root canal treatment requires knowledge of tooth morphology, appropriate access preparation, and a thorough examination of the tooth's interior. Thus, clinicians should carefully employ various methods for assessing the anatomy of the entire root canal system to prevent failure in locating the second mesiobuccal canal. This canal can be located by modifying the access cavity design and utilizing specific instruments to improve the second mesiobuccal canal system visualization.

La falta de localización de un sistema completo de canal afecta el pronóstico del tratamiento de éste. La omisión de un tratamiento de canal es uno de los motivos más frecuentes por las que el tratamiento de canal fracasa. La prevalencia del segundo canal mesiovestibular en el segundo molar superior es relativamente alta y tiene una variedad de configuraciones. Por tanto, el conocimiento de su morfología es necesario en endodoncia clínica. Esta revisión presentó el canal en términos de su prevalencia, clasificación, características anatómicas y el método para localizar el segundo canal mesiovestibular en el segundo molar superior. El tratamiento de canal requiere conocimiento de la morfología del diente, una preparación adecuada del acceso y un examen exhaustivo del interior del diente. Por lo tanto, los dentistas deben emplear cuidadosamente varios métodos para evaluar la anatomía de todo el sistema de canales radiculares para evitar fallas en la localización del segundo canal mesiovestibular. Este canal se puede localizar modificando el diseño de la cavidad de acceso y utilizando instrumentos específicos para mejorar la visualización del sistema del segundo canal mesiovestibular.

Effect of the timing of primary endodontic treatment and dosage of radiation therapy on the filling material removal.

This study investigated the effect of the timing of primary endodontic treatment and dosage of radiotherapy on the remaining filling material (RFM) during endodontic reintervention. 60 single-rooted human mandibular premolars were distributed into five groups (n = 12), according to the timing and dosage of radiation (55Gy or 70Gy): NegativeCG-non-irradiated teeth; Endo-pre-RT55/70-obturation before irradiation (55Gy or 70Gy); Endo-post-RT55/70-obturation and reintervention after irradiation (55Gy or 70Gy). Roots were cleaved and analysed under stereomicroscope and Scanning Electron Microscope to quantify (%) the RFM. Experimental groups had a significantly greater amount (p < 0.05) of RFM in the middle and apical thirds than the control group, except for Endo-pre-RT55 in the middle third (p < 0.0001). The apical third had greater amount of RFM (p < 0.05). Radiation therapy, before and after primary endodontic treatment, increased the amount of RFM, regardless of the dose delivered. When necessary, reintervention preferably must be performed before radiation therapy.

Evaluation of Antimicrobial Properties, Cell Viability, and Metalloproteinase Activity of Bioceramic Endodontic Materials Used in Vital Pulp Therapy.

This study aimed to evaluate the antimicrobial properties, cell viability, and matrix metalloproteinase (MMP) inhibition capacity of several endodontic materials aimed at vital pulp therapy: Pro Root MTA®, EndoSequence®, Biodentine®, MTA Angelus®, TheraCal LC®, and BioC Repair®. The materials were prepared according to the manufacturer's instructions. Antimicrobial tests were conducted using a microcosm biofilm model, cell viability was assessed using murine fibroblasts (L929), and MMP activity was analyzed through electrophoresis. The results showed that BioC Repair®, Biodentine®, and EndoSequence® exhibited similar antimicrobial properties, while MTA Angelus® and ProRoot MTA® had inferior results but were comparable to each other. In terms of cell viability, no significant differences were observed among the materials. EndoSequence® demonstrated the highest MMP inhibition capacity. In conclusion, BioC Repair®, Biodentine®, EndoSequence®, and TheraCal® showed better antimicrobial properties among the tested materials. The materials did not exhibit significant differences in terms of cytotoxicity. However, EndoSequence® displayed superior MMP inhibition capacity.

Biological response to endodontic treatment in one versus two-visit: a systematic review and meta-analysis of animal studies.

OBJECTIVES: To perform a systematic review of animal studies that compared the histopathological characteristics between teeth with apical periodontitis after endodontic treatment in one or two visits. MATERIALS AND METHODS: This systematic review was registered on the International Prospective Register of Systematic Reviews (PROSPERO) - CRD42022340849. Studies were collected from PubMed/MEDLINE, LILACS, EMBASE, Livivo, SciELO, Web of Science, Scopus, and Cochrane Library and manual and gray literature searches. Animal studies that evaluated histological characteristics after endodontic treatment of teeth with apical periodontitis in one or two visits were included. Risk of bias analysis of the included studies was performed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool. Data synthesis of the included studies with quantitative data was performed, and meta-analysis was conducted with the Comprehensive Meta-Analysis software, using the random effects model and odds ratio (OR). RESULTS: Eighteen studies met the inclusion criteria (Kappa = 0.891). Meta-analyses indicated values in inflammatory infiltrate intensity with effect size of 5.5% (95% CI: 0.020-0.148; p < 0.001), periodontal ligament thickness: 25.6% (95% CI: 0.134-0.487; p < 0.001), dentin resorption: 13% (95% CI: 0.015-1.141; p = 0.066), cementum resorption: 7.1% (95% CI: 0.015-0.325; p = 0.001), bone resorption: 1.4% (95% CI: 0.002-0.130; p < 0.001), mineralized tissue resorption: 42.8% (95% CI: 0.110-1.671; p = 0.222), biological apical sealing: 13.1% (95% CI: 0.055-0.314; p < 0.001), and presence of microorganisms: 10.3% (95% CI: 0.014-0.747; p = 0.025). CONCLUSIONS: When considering animal studies, the two-visit endodontic treatment, using calcium hydroxide-based intracanal medication, resulted in better biological repair characteristics. CLINICAL RELEVANCE: A two-visit endodontic treatment with calcium hydroxide-based intracanal medication yields superior histopathological outcomes.

Occlusal Loading Effect on Stress Distribution of Endodontically Treated Teeth: Finite Element Analysis Study.

AIM: Evaluate the influence of occlusal loading on the stress distribution of endodontically treated teeth after root canal preparation with different file's sizes and tapers by means of finite element analysis. METHODOLOGY: Seven three-dimensional models of a single-rooted, single-canal lower second premolar were established, one healthy control and six endodontically treated and restored models. The shape of root canal preparations followed file configurations 30/.05, 30/.09, 35/.04, 35/.06, 40/.04, and 40/.06. Von- Mises equivalent stresses were calculated by applying 30 N, 90 N and 270 N loads to the buccal cusp tip, each one at 90º, 45º and 20º angles from the occlusal plane simulating occlusion, dental interference and laterality, respectively. RESULTS: 45º loading was more prone to formation of higher stress values. The simulation of occlusion and laterality resulted in maximum stress areas located at the inner side of the root curvature, while under occlusal interference they were on the lingual surface over the tooth's long axis. CONCLUSIONS: The angulation of occlusal loading and magnitude were determinants for stress distribution on dental structure. Both variations of size and taper were not determinants for the increase in the maximum stress areas.

Morphological assessment of the isthmus in mesial root canals of first mandibular molars / Avaliação morfológica do istmo nos canais radiculares mesiais dos primeiros molares inferiores

ABSTRACT Root canal morphology and its anatomical variations pose a great challenge to endodontists Aim The aim of this in silico study was to perform a qualitative and quantitative analysis of the threedimensional morphological characteristics of the isthmus in the mesial root canals of mandibular molars using microcomputed tomography (micro-CT) Material and Method Six hundred first mandibular molars were selected, including 317 with two mesial canals with isthmuses between the canals, and fully formed root. Isthmus morphology was determined in 3D longitudinal sections using Fan et al. (2010) classification. Root length, and the volume and area of apical and coronal level were measured. Additionally, the structural model index (SMI) of the canals were also assessed Results The prevalence of isthmuses in the mesial root canals was 32% type II, 29% type III, 22% type IV, and 17% type I. The root length was found to be 9.1±0.5 mm, the volume and area, of all root canal system, were 41.8±40.1 mm3 and 63.6±24.2 mm2 respectively. The isthmi volume and area alone were 11.06±9.03 mm3 and 30.02±11.02 mm2. The study confirmed that isthmuses are present in mesial canals of mandibular first molars, being more frequent in the apical third Conclusion The high prevalence of isthmuses with complex morphological features underscores the importance of using intracanal medications to disinfect areas unprepared by instruments.

RESUMO A morfologia do canal radicular e suas variações anatômicas representam um grande desafio para os endodontistas. O objetivo deste estudo ex vivo foi realizar uma análise qualitativa e quantitativa das características morfológicas tridimensionais do istmo nos canais mesiais de molares inferiores por meio de microtomografia computadorizada (micro-CT) Material e Método Foram selecionados 600 primeiros molares inferiores, incluindo 317 com dois canais mesiais com istmos e raiz totalmente formada. A morfologia do istmo foi determinada em cortes longitudinais 3D usando a classificação Fan et al. (2010). Foram mensurados o comprimento da raiz, o volume e a área apical e coronal e da cavidade pulpar. Adicionalmente, também foram avaliados o structure model index (SMI) dos canais Resultados A prevalência de istmos nos canais mesiais foi de 32% tipo II, 29% tipo III, 22% tipo IV e 17% tipo I. O comprimento da raiz foi de 9,1±0,5 mm, o volume e a área de todo o sistema de canais radiculares foram de 41.8±40.1 mm3 e 63.6±24.2 mm2, respectivamente. O volume e área do istmo isoladamente foram 11.06±9,03 mm3 e 30.02±11.02 mm2. O estudo confirmou que os istmos estão presentes em canais mesiais dos primeiros molares inferiores, sendo mais frequentes no terço apical Conclusão A alta prevalência de istmos com características morfológicas complexas ressalta a importância do uso de medicação intracanal para desinfecção de áreas não tocadas por instrumentos.

Post-treatment Apical Periodontitis in Primary Non-surgical Root Canal Treatment: A Multiple Correspondence Analysis.

Introduction: The presented study aimed to characterise periapical disease in teeth with primary non-surgical root canal treatment in persistent or emergent categories and their risk association. Methods: A retrospective observational study that evaluated permanent teeth with primary non-surgical root canal treatment, was conducted clinically and radiographically for over one year. The following variables were analysed: gender, age, type and location of tooth, previous diagnosis, treatment conditions, and type of coronal restoration. The supplementary variables included the perspectives of the treatment outcome, such as Remains normal, Improvement, and Failure. Statistical analysis was performed using a univariate analysis that estimated the average and proportion for each factor according to the result of the primary non-surgical root canal treatment. The multiple correspondence analysis identified the hierarchy between active variables and their association with the results. Results: A total of 232 teeth in 155 participants were analysed. A χ2 value, (P=0.023) showed that the emergent disease is associated with patients around the age of 50. The multiple correspondence analysis identified a tendency of grouping between the emergent disease and the short filling category, followed by symptomatic pulpitis as a previous diagnosis. The persistent disease was associated with errors and overfillings. An inadequate root filling and taper density adversely impacted the treatment outcome. Conclusions: The length of obturation influenced the presence of failure. Short fillings were associated with emerging periapical disease. Errors and overfillings contributed to the persistent disease in the populations studied.

The influence of anxiety on pain perception and its repercussion on endodontic treatment: a systematic review.

OBJECTIVE: To evaluate the influence of dental anxiety on the perception of pain before and during endodontic treatments. MATERIALS AND METHODS: The PRISMA checklist was followed. A search was conducted in Scopus, Medline/PubMed, The Cochrane Library, and Web of Science databases. Based on PECOS criteria, the first outcome was a possible association between pre-operative pain and anxiety. The second outcome was a possible association between intraoperative pain and anxiety. The type of studies was observational. The JBI Critical Appraisal Checklist was used to evaluate the methodological quality of articles. The certainty of the evidence was analyzed using the GRADE approach. RESULTS: Four articles were included with a total of 471 patients. Two studies found a positive association between pain and pre-endodontic treatment anxiety. Three studies investigated the relationship between anxiety and intraoperative pain; two identified an extremely significant positive association. One article noted that anxiety influences pain expectancy. The studies were of good quality as assessed by the JBI Critical Appraisal Checklist for cross-sectional studies. However, the certainty of the evidence was considered low and very low. CONCLUSIONS: Dental anxiety can be directly associated with pre- and intraoperative pain during endodontic procedures. CLINICAL RELEVANCE: It is necessary to identify patients with dental anxiety to employ therapies to bring their anxiety under control, avoiding the increase of endodontic infections, and the postponement and evasion of endodontic treatments.

Mechanical activation with Easy Clean device enhanced organic tissue removal from simulated internal root resorption in a laboratory evaluation.

BACKGROUND: Considering the irregular shape of the root canal, removing inflamed pulp and granulation tissue completely from internal resorption cavities during chemomechanical preparation can be challenging. This study aimed to evaluate the effectiveness of passive ultrasonic irrigation (PUI) compared to mechanical activation with Easy Clean in the removal of organic tissue from simulated areas of internal root resorption. METHODS: The root canals of 72 extracted single-rooted teeth with oval canals were instrumented with Reciproc R25 instruments. After root canal preparations, the specimens were split longitudinally, and semicircular cavities were prepared using a round bur on each half of the roots. Samples obtained from bovine muscle tissue were weighed and adapted into semicircular cavities. The roots were reassembled and joined, and the teeth were divided into six groups (n = 12) according to the irrigation protocol: Sodium hypochlorite (NaOCl) without activation; NaOCl + PUI; NaOCl + Easy Clean; distilled water without activation; distilled water + PUI; and distilled water + Easy Clean. After irrigation protocols, the teeth were disassembled, and the remaining organic tissue was weighed. Data were analyzed by two-way ANOVA and Tukey's post hoc test (p < 0.05). RESULTS: None of the experimental protocols totally removed the bovine tissue from simulated cavities. Tissue weight reduction was significantly affected by the activation method (p < 0.05) and by irrigation solution (p < 0.05). Groups with NaOCl irrigation presented higher tissue weight loss when compared to distilled water, for all irrigation methods (p < 0.05). The use of Easy Clean resulted in the greatest tissue weight loss (42.0%-Distilled water/45.5%- NaOCl) compared to those of PUI (33.3%-Distilled water/37.7%- NaOCl) and no activation (33.4%-Distilled water/38.8%- NaOCl) (p < 0.05). However, no differences were observed between PUI and no activation groups (p > 0.05). CONCLUSIONS: Mechanical activation with Easy Clean enhanced organic tissue removal from simulated internal resorption more effectively than PUI. Easy Clean for agitation of the irrigating solution is effective in removing simulated organic tissues from artificial internal resorption cavities, being an alternative to the use of PUI.

Effect of different disinfection protocols in bacterial viability of an intraradicular biofilm formed in situ

Abstract The present study aimed to evaluate bacterial viability after the use of different disinfection protocols in root canals infected with a multispecies biofilm (MB) formed in situ. Palatal roots with a single canal were obtained from extracted maxillary molars and sterilized before being inserted into the mouth. The roots were contaminated with a MB in an intraoral appliance worn by ten volunteers. All volunteers wore six roots simultaneously in two intraoral devices for 21 days. One root from each volunteer was assigned to each group (n=10): PUI - passive ultrasonic irrigation; EC - Easy Clean; XPF - XP-endo Finisher; aPDT - antimicrobial photodynamic therapy; CI - conventional irrigation; and NC - negative control. The samples were evaluated under confocal laser scanning microscopy. The percentage of viable cells (VC) was calculated over the total percentage of MB biovolume. Data were statistically analyzed (α=5%). The cell viability in the entire root canal or for each third was compared between groups (Kruskal-Wallis test, Dunn post-hoc test) and for the same group (Friedman test, Dunn post-hoc test). Disinfection protocols were not significantly different from each other (P>.05). Samples in EC, PUI, and aPDT had lower cell viability than in NC (P<.05). In the coronal third of samples in the EC, XPF, PUI and aPDT, the percentage of VC biovolume was lower than in the NC (P<.05). The percentage of VC in EC samples was lower in the coronal and middle thirds than in the apical third (P<.05). EC, PUI and aPDT had significant effects on cell viability in intraradicular multispecies biofilm formed in situ when compared with untreated samples.

Resumo O presente estudo teve como objetivo avaliar a viabilidade bacteriana após o uso de diferentes protocolos de desinfecção em canais radiculares infectados com um biofilme multiespécies (MB) formado in situ. Raízes palatinas com canal único foram obtidas de molares superiores extraídos e esterilizadas antes de serem inseridas na boca. As raízes foram contaminadas com MB em um aparelho intraoral usado por dez voluntários. Todos os voluntários usaram seis raízes simultaneamente em dois dispositivos intrabucais por 21 dias. Uma raiz de cada voluntário foi atribuída a cada grupo (n=10): PUI - irrigação ultrassônica passiva; EC - Easy clean; XPF - XP-endo Finisher; aPDT - terapia fotodinâmica antimicrobiana; IC - irrigação convencional; e, NC - controle negativo. As amostras foram avaliadas em microscopia confocal de varredura a laser. A porcentagem de células viáveis (VC) foi calculada sobre a porcentagem total do biovolume de MB. Os dados foram analisados estatisticamente (α=5%). A viabilidade celular em todo o canal radicular ou em cada terço foi comparada entre os grupos (teste de Kruskal-Wallis, teste post-hoc de Dunn) e no mesmo grupo (teste de Friedman, teste post-hoc de Dunn). Os protocolos de desinfecção não foram significativamente diferentes entre si (P>0,05). Amostras dos grupos EC, PUI e aPDT apresentaram menor viabilidade celular do as do NC (P<0,05). No terço cervical das amostras do EC, XPF, PUI e aPDT, a porcentagem de biovolume de VC foi menor do que no NC (P<0,05). A porcentagem de VC nas amostras do EC foi menor nos terços cervical e médio do que no terço apical (P<0,05). EC, PUI e aPDT tiveram efeitos significativos na viabilidade celular do biofilme multiespécies intrarradicular formado in situ quando comparado com amostras não tratadas. Estudos clínicos devem investigar o papel da redução de cargas bacterianas viáveis no sistema de canais radiculares para o sucesso do tratamento endodôntico.

Therapeutic Approach in Large Periapical Cyst: Clinical Case Report / Abordagem Terapêutica em Cisto Periapical de Grande Proporção: Relato de Caso Clínico

Periapical cysts of endodontic origin originate from an infection that affects the apical region, causing pulpal necrosis that stimulates an inflammatory response. Among many pathologies found on radiographs, one of them is the root cyst, considered to be a lesion frequently found in the maxilla and mandible, associated with the apex of a tooth with pulp necrosis. They present slow growth and are discovered in routine examinations because they are asymptomatic. Due to the chronic aggression, the lesion does not present painful symptoms in most cases, and grows slowly, thus being able to reach large extensions, with the presence of swelling and sensitivity, as well as slight mobility in the affected tooth and adjacent ones. The objective of this study was to report a clinical case of swelling in the anterior region of the mandible, which was diagnosed as a periapical cyst, in this way the treatments performed and the final result after 18 months of follow-up will be reported. However, to achieve good results during periapical cyst treatment, it is necessary to make a correct diagnosis, followed by adequate planning, always performing clinical and radiographic follow-up, in addition to the patient's cooperation, so that good results can be achieved during the treatment. It can be observed that a well-performed endodontic treatment, associated with a elaborated surgical technique, in addition to anatomopathological evidence and radiographic follow-up, make the therapeutic success to be obtained in cases of large periapical cysts.(AU)

Os cistos periapicais de origem endodôntica, originam-se a partir de uma infecção que acomete em região apical, ocasionando uma necrose pulpar que estimula uma resposta inflamatória. Das várias patologias encontradas radiograficamente, o cisto radicular tem sido o mais frequente encontrado, tanto em maxila, quanto em mandíbula, associado ao ápice de um dente com necrose pulpar. Apresentam crescimento lento e são descobertos nos exames de rotina, por serem assintomáticos. Devido a agressão crônica, a lesão não apresenta sintomatologia dolorosa, na maioria dos casos, tendo seu crescimento lento, desta maneira podendo atingir grandes extenções, com presença de tumefação e sensibilidade, além de leve mobilidade no dente acometido e nos adjacentes. O objetivo deste estudo foi relatar um caso clínico de tumefação na região anterior de mandíbula, o qual foi diagnosticado como cisto periapical, desta forma serão relatados os tratamentos realizados e o resultado final após 18 meses de acompanhamento. Contudo, para que sejam alcançados bons resultados durante o tratamento do cisto periapical é necessário realizar um correto diagnóstico, seguido por um planejamento adequado, realizando sempre o acompanhamento clínico e radiográfico, além da colaboração do paciente, para que possam ser atingidos bons resultados durante o tratamento. Pode-se observar que um tratamento endodôntico bem realizado, associado à uma técnica cirúrgica bem elaborada, além de comprovação anatomo-patológica e acompanhamento radiográfico, fazem com que o sucesso terapêutico seja obtido para os casos de cistos periapicais de grande proporção.(AU)

Intracanal Microbiological Contamination Reduction Using Low-intensity Laser Associated with a Photosensitizer - In Vivo Study in Teeth of Dogs.

This study evaluated the efficacy of photodynamic therapy using the photosensitizer azulene and low-intensity laser associated with standard root chemical-surgical preparation (performed with 0.5% sodium hypochlorite) in dogs. Twenty animals from the Veterinary Hospital of the School of Veterinary Medicine and Animal Science, University of São Paulo (HOVET-FMVZ/USP) and treated at the Compared Dentistry Laboratory (Laboratório de Odontologia Veterinária [LOC]-FMVZ/USP) were included. Each subject possessed one single rooted tooth with complete root formation, pulp necrosis, complicated crown fracture and periapical bone rarefaction at the time of the radiographic examination. The endodontic treatment was performed in all dogs, which were divided into two equal groups. For group one, the standard chemical-surgical preparation was followed by the photodynamic therapy to evaluate the role of azulene after instrumentation. For group two, the photodynamic therapy was followed by the standard chemical-surgical preparation to evaluate the antimicrobial action of azulene before instrumentation. The results show that intracanal photodynamic therapy is efficient in eliminating unspecified bacterial and Enterococcus organism loads. In addition, this therapeutic modality reduces yeast contamination. The photodynamic therapy showed similar efficacy compared to standard chemical-surgical preparation. The application order of therapeutic modalities does not influence intracanal disinfection in both cases. This study shows that photodynamic therapy with low-intensity laser and azulene as a photosensitizer is a feasible alternative for improving treatment outcomes in routine practice of veterinary dentistry.

Is There a Relationship between Laser Therapy and Root Canal Cracks Formation? A Systematic Review.

Introduction: Crack formation has become an important issue for endodontists, as it can be decisive for the long-term prognosis of the endodontically treated tooth. Since the applicability of laser in endodontics has become frequent, this systematic review aimed to evaluate the association between laser therapy and the formation of cracks in the dentinal structure of the root canal. Materials and Methods: A search was performed in PubMed, Scopus, Web of Science, and Virtual Health Library, as well as in the gray literature, on September 24, 2021. Studies that evaluated the formation of cracks in human root dentin due to different types of lasers were included. The risk of bias was assessed following the modified version of the Consolidated Standards of Reporting Trials (CONSORT) checklist tool. A meta-analysis was performed to evaluate (i) the total number of crack incidences; (ii) complete crack formation; (iii) incomplete crack formation; (iv) intra-dentinal crack formation between ultrasonic tips and laser use. The mean difference was calculated with a 95% confidence interval in a fixed-effect model, the heterogeneity was tested using the I2 index with level of significance of 5%. Results: Of the 22 studies included in this review, 15 have shown that lasers can form cracks in root dentin, including those that performed baseline assessment of samples. The meta-analysis confirmed no difference in crack formation between ultrasonic tips and laser devices. Conclusions: Laser therapy has been gaining prominence in endodontics and that irradiation can form and propagate cracks in the dentinal structure of the root canal assessed by in vitro studies. This is a critical concern for endodontists as it affects the strength and longevity of the tooth. Future research is encouraged to seek the standardization of good methodological practices and achieve establishing parameters to minimize harmful effects of laser on dentin.

Antimicrobial effectiveness of ultrasonic irrigation in root canal treatment: a systematic review of randomized clinical trials and meta-analysis.

OBJECTIVE: The objective of this systematic review and meta-analysis (SRM) was to answer the question as to whether the use of ultrasonic irrigation (UI) results in better antimicrobial activity in root canal disinfection compared to conventional irrigation (CI). METHODS: A literature search was performed in the main scientific databases, carried out until October 2021. The eligibility criteria were randomized clinical trials (RCTs). Two meta-analyses were conducted using R software with the "META" package. The mean difference (MD) and odds ratio (OR) measure of effect were calculated. The fixed effect model was applied with a 95% confidence interval. The Cochrane collaboration scale was used to assess risk of bias and the GRADE tool to assess the quality of evidence. RESULTS: A total of 1782 records were screened, and 12 studies meeting the criteria were included in this review. A low risk of bias was observed for most domains, except allocation concealment that was considered unclear. The certainty of evidence was classified as moderate in the OR meta-analyses and low in the MD meta-analyses. Ultrasonic irrigation resulted in a better antimicrobial effect in both meta-analyses, MD 1.42 [1.60; 1.23] p < 0.0001, I2 = 80%; and OR 3.86 [1.98; 7.53] p< 0.0001, I2 = 28.7%. CONCLUSION: Within the limitations of this SRM, UI presented better antimicrobial efficacy than CI. CLINICAL RELEVANCE: UI should be used by clinicians as it promotes better antimicrobial efficacy in patients undergoing endodontic treatment.