Bypass de instrumento endodôntico fraturado: relato de caso / Bypass of a fractured endodontic instrument: case report

Introdução: Mesmo com toda evolução tecnológica desses instrumentos, com o desenvolvimento das limas de liga de níquel-titanio (NiTi) e sistemas mecanizados, as fraturas podem ocorrer durante o preparo químico/mecânico. Existem três abordagens mais regulamente aplicadas para solucionar essa intercorrencia: tentativa de remoção do instrumento com ultrassom, tentativa de ultrapassálo (bypass) ou a obturação do segmento. Objetivo: Relatar um caso da técnica de bypass em instrumento fraturado no canal radicular. Descrição do caso: Paciente, sexo feminino, 47 anos, brasileira, sem condições sistêmicas associadas, foi encaminhada à clínica do Curso de Odontologia da UNIFENAS, Divinópolis, Minas Gerais, Brasil, para resolução de fratura de instrumento no canal mésio- vestibular do primeiro molar superior direito (16). Optou-se pelo tratamento pela técnica de bypass, que envolveu as seguintes etapas: anestesia, abertura, utilização de lima C-Pilot #08 para ultrapassar o instrumento fraturado, odontometria, escalonamento regressivo a partir da lima k#20, desinfecção com hipoclorito de sódio 5%, medicação com hidróxido de cálcio por 21 dias, agitação da substância irrigadora e obturação dos canais radiculares. Conclusão: O bypass ao instrumento é uma técnica conservadora, eficaz e uma solução adequada em casos de fratura de limas endodônticas dentro dos canais radiculares. Essa técnica visa preservar o máximo possível da estrutura dental original, evitando procedimentos mais invasivos.(AU)

Introduction: Even with all technological evolution of these instruments, with the development of nickel-titanium alloy (NiTi) files and mechanized systems, fractures can occur during chemical/mechanical preparation. There are three most commonly applie to resolve this complication: attempting to remove the instrument with ultrasound, attempting to bypass it, or obturating the segment. Objective: To report a case of bypass technique in fractured instrument in the root canal. Case description: A 47-year-old female patient from Brazil, with no associated systemic conditions, was referred to the clinic of the Dentistry Course at UNIFENAS, Divinópolis, Minas Gerais, Brazil, for resolution of an instrument fracture in the mesio-vestibular canal of the right upper first molar (16). Treatment was performed using the bypass technique, which involved the following steps: anesthesia, opening, use of a C-Pilot #08 file to bypass the fractured instrument, odontometry, regressive scaling from the k#20 file, disinfection with 5% sodium hypochlorite, medication with calcium hydroxide for 21 days, agitation of the irrigating substance and root canal filling. Conclusion: Instrument bypass is a conservative, effective technique and an adequate solution in cases of endodontic file fracture within root canals. This technique aims to preserve as much of the original tooth structure as possible, avoiding more invasive procedures.(AU)

Endodontic file separation and its management among dentists in Punjab, Pakistan: a cross-sectional study

The study aimed to find the incidence and awareness of endodontic instrument separation and its management among dental house officers, postgraduate trainees, demonstrators, consultants, and general dentists. Methods: This online questionnaire-based cross-sectional study was conducted with the approval of the IRB in private and public dental hospitals and dental clinics in Punjab. The authors developed the survey tool, which comprises 24 closed-ended items regarding demographics, the incidence of file separation, and awareness about its management. The data were analyzed using IBM SPSS version 24. The Chi-Square Test was used to compare percentages of categorical variables. Results: Postgraduate trainees experienced the most instrument separations (43.6%), made the most retrieval attempts (49.2%), and experienced the most secondary errors during retrieval (52.1%) (p<0.001). Around four out of ten respondents always informed the patients (39.6%) and department (41.6%) about errors. Manual files (69.8%), stainless steel files (75.8%), and short files (60.4%) were more frequently separated, and the most frequent cause was older fatigue files (57.7%). Manual files were more frequently broken in public dental institutes (p=0.003). Two-thirds of the file separations (72.5%) occurred during cleaning and shaping in the apical third of molars (65.1%), especially in mesiolingual canal (56.4%). Bypass attempt was the most common in symptomatic teeth (47.7%). Conclusions: Preventive approaches such as limiting file reuse and constructing a glide path can reduce the occurrence of file separation. Operators should be familiar with the number of uses of the instrument before fatigue and should be trained through workshops and refresher courses

Qualitative Analysis of Root Canal Treatments performed by Undergraduate Students: A Retrospective Study

ABSTRACT Objective: Toanalyze the technical quality of endodontic treatment carried out at the undergraduate dental clinics. Material and Methods: Random radiographic records of 92 patients' were selected who received endodontic treatment by the undergraduate students from June 2018 to July 2019. The quality of root canal filling was determined in relation to the adequate density, length, and taper. Statistical analysis was performed by using GraphPad (Prism 5), and to determine the association between different variables Chi-square test was used. Results: Adequate technical quality of canal obturation conducted by the undergraduate students was found in less than 65% of the cases. The frequency of adequate root canal taper was significantly greater in maxillary teeth (75%) as compared to mandibular teeth (33%); however, adequacy of acceptable density was found more in maxillary teeth (62%) as compared to mandibular teeth (55%).A statistically significant difference was seen in the quality of root canal fillings between anterior and posterior teeth (p=0.001). Conclusion: The root canal therapy performed by undergraduate students was less than optimum in terms of technical quality. Hence, it is suggested that the endodontic training courses delivered at pre-clinical and clinical levelsfor undergraduate students must be thoroughly revised.

Success Rate of Contemporary Regenerative Endodontic Therapy and the Expected Outcomes of the Endodontic Microsurgery: A Systematic Review and Meta-Analysis

ABSTRACT Objective: To examine the level of the accumulating success of the modern Resin-Based Endodontic Surgery (RES) and comparison with Endodontic Microsurgery (EMS) and finally offer a replacement at the predicted final results of EMS. Material and Methods: MEDLINE, PubMed, Cochrane Library, Embase, ISI, Google Scholar have been utilized as electronic databases for systematic literature until 2019. Therefore, Endnote X9, which can be provided in the market, has been applied to manage the electronic titles. Searches have been made with keywords "Endodontic Microsurgery OR EMS", "Resin-Based Endodontic Surgery OR RES", "Regenerative Endodontic Therapy", "Root-End Filling", "Root-End Surgery", "Periapical Surgery" and "Endodontics". Thus, this systematic review has been conducted concerningthe basic investigation of the PRISMA Statement-Preferred Reporting Items designed for the Meta-analyses and Systematic Reviews. Results: A total of RES =19 and EMS =31 with potential pertinent abstracts and topics were discovered in manual and electronic searches. Then, three articles for RES and four studies for EMS publications satisfied our inclusion criteria necessary for systematically reviewing the studies. The analysis showed the success rate for EMS as equal to 1.16 times the probability of the success rate for RES. Conclusion: Micro-surgical procedures superiorly achieved the predictable high success rate for the Root-end surgery compared to conventional methods.

Influence of the Vehicle on the Tissue Reaction and Biomineralization of Fast Endodontic Cement

ABSTRACT Objective: To investigate the tissue response and the biomineralization ability of CER prepared with epoxy resin or water compared to Mineral Trioxide Aggregate (MTA). Material and Methods: Polyethylene tubes containing materials or empty tubes for control were inserted into the subcutaneous tissues of 30 rats. After 7, 15, 30, 60, and 90 days, the rats were killed and the tubes were removed for analysis using hematoxylin-eosin staining, von Kossa staining, and under polarized light. Inflammation was graded through a score system; the thickness of the fibrous capsule was classified as thin or thick; the biomineralization ability was recorded as present or absent. The results were statistically analyzed using the Kruskal-Wallis test (p<0.05). Results: Histologic analysis performed after 7 and 15 days for CER prepared with epoxy resin or water and for MTA showed moderate inflammation and a thick fibrous capsule (p>0.05). After 30, 60, and 90 days, mild inflammation, and a thin fibrous capsule were observed in all groups (p>0.05). Conclusion: All materials had structures positive for von Kossa and birefringent to polarized light. CER epoxy resin showed biocompatibility and biomineralization similar to CER water and MTA.

Comparison of Detection Rate of Root Canal Orifices of Maxillary First Molar Using Various Techniques: An in-vivo Study

ABSTRACT Objective: To compare the detection rate of root canal orifices of maxillary first molar by various techniques in the Indian population. Material and Methods: A total of 50 maxillary 1st molar cases were selected and sequentially divided into four groups: Group I: Naked eye; Group II: Surgical loupe; Group III: Surgical operating microscope; and Group IV: Fluorescein sodium dye. After access opening, the number of root canal orifices was detected in all cases with these methods. Results: By naked eye and surgical loupe, a total of 171 root canal orifices were detected, by a surgical operating microscope, 176, and by fluorescein sodium dye, 177 root canal orifices were detected. The detection rate of root canal orifices is as follows: Group I (96.61%) = Group II (96.61%) < Group III (99.44%) < Group IV (100%) and detection rate of MB-2 canal orifices Group I (40%) = Group II (40%) < Group III (50%) < Group IV (52%). No significant difference in the number of canal orifices detected could be seen for any of the comparisons. No significant difference was observed between the naked eye and surgical loupe techniques. Although the surgical operating microscope detected more root canal orifices, it did not have a significantly higher detection than the other two techniques. Conclusion: No significant difference was seen among various methods. However, the use of a surgical operating microscope and fluorescein sodium dye increased the detection rate of root canal orifices.

Influência do ProTaper/ProTaper Next, comparado a outros sistemas rotatórios/reciprocantes, no risco e na intensidade da dor pós-operatória após instrumentação endodôntica em pacientes adultos: uma revisão sistemática e metanálise / Influence of ProTaper/ProTaper Next, compared to other rotatory/reciprocating systems, on the risk and intensity of postoperative pain after endodontic instrumentation in adult patients: a systematic review and meta-analysis

Introdução: O sucesso da terapia endodôntica depende não apenas de sua eficácia e conclusão adequada, mas também do mínimo desconforto do paciente. Objetivo: O objetivo dessa revisão sistemática e metanálise é avaliar o risco e a intensidade da dor endodôntica pós-instrumentação em pacientes adultos. Métodos: Uma pesquisa abrangente foi realizada no MEDLINE via PubMed, Scopus, Web of Science, LILACS, BBO e Cochrane Library e SIGLE, sem restrições. Também foram pesquisadas a conferência anual dos resumos da IADR (1990-2016) e o registro de ensaios não publicados e em andamento. As dissertações e teses foram pesquisadas utilizando-se os bancos de dados das dissertações ProQuest e das bases de teses Periódicos Capes. Apenas ensaios clínicos randomizados que compararam o risco ou a intensidade da dor resultante do tratamento endodôntico em pacientes adultos foram incluídos. Resultados: Após a remoção das duplicatas, 827 artigos foram identificados. Após a triagem do título e resumo, restaram 26 estudos, dos quais 13 foram ainda excluídos, permanecendo 10 para análise qualitativa e 7 para a metanálise. Não foi observada diferença significativa no risco/ intensidade da dor após o tratamento endodôntico nesse estudo. O risco de dor foi de 1,09, com intervalo de confiança de 95%, variando de 0,87 a 1,38 (p=0,45). A diferença padronizada g de Hedges nas médias da intensidade da dor após 24 horas foi de ­ 0,05, com intervalo de confiança variando de ­ 0,21 a 0,11 (p=0,53). Conclusões: Nessa metanálise, não foram encontradas diferenças no risco e na intensidade da dor após o tratamento endodôntico com ProTaper e outros sistemas rotatórios ou reciprocantes (AU).

Introduction: The success of endodontic therapy depends not merely on their efficacy and proper completion but also on minimal patient discomfort. The purpose of this systematic review and meta-analysis is to evaluate the risk and intensity of post instrumentation endodontic pain in adult patients. Methods: A comprehensive search was performed in the MEDLINE via PubMed, Scopus, Web of Science, LILACS, BBO and Cochrane Library and SIGLE without restrictions. The annual conference of the IADR abstracts (1990-2016), and unpublished and ongoing trials registry were also searched. Dissertations and theses were searched using the ProQuest Dissertations and the Periodicos Capes Theses Databases. Only randomized clinical trials that compared the risk or intensity of pain resulting from endodontic treatment in adult patients were included. Results: After the removal of duplicates, 827 articles were identified. After title and abstract screening, 26 studies remained. Thirteen studies were further excluded while 10 studies remained for qualitative analyses and 7 for the meta-analysis. No significant difference in the risk/intensity of pain after endodontic treatment was observed in this study. The risk of pain ratio was 1.09, with a 95% confidence interval of 0.87 to 1.38 (p = 0.45). The Hedges g standardized difference in means of pain intensity at 24 h was -0.05, with a confidence interval varying from -0.21 to 0.11 (p = 0.53). Conclusions: No differences in risk and intensity of pain after endodontic treatment with ProTaper and other rotatory or reciprocating systems were found in this meta-analysis (AU).

Instrumentação reciprocante em canal mésiovestibular de molar superior após fratura de lima endodôntica: relato de caso / Reciprocal instrumentation in the mesiobuccal canal of the upper molar after endodontic file fracture: case report

Objetivo: reportar um caso clínico de ultrapassagem de instrumento endodôntico fraturado em terço médio de canal mésiovestibular de molar superior permanente, utilizando a técnica de instrumentação reciprocante associada à instrumentação convencional manual e ao gel de E.D.T.A. 24%. Relato de caso: paciente do sexo masculino, 24 anos, normossistêmico, compareceu ao consultório odontológico privado com queixa de dor espontânea e encaminhamento para tratamento endodôntico do dente 17. O diagnóstico foi pulpite irreversível sintomática com indicação de tratamento endodôntico primário. A lima principal escolhida foi a Reciproc® R25 M-wire (VDW), que, durante a instrumentação do canal mésiovestibular, sofreu fratura por torção em terço médio, inviabilizando a continuação em direção apical. Considerações finais: a associação da técnica convencional manual das limas Hedströen com a técnica reciprocante de corte reverso da lima Wave One® Gold Primary e o uso do gel de E.D.T.A. 24% permitiram ultrapassagem do fragmento de lima fraturado em terço médio do canal mésiovestibular do dente 17, promovendo selamento hermético, limpeza, modelagem e obturação satisfatórias.(AU)

Objective: to report a clinical case of a fractured endodontic instrument in the middle third of the permanent maxillary molar maxillary canal using the technique instrumentation reciprocation with technique to conventional manual instrumentation and the E.D.T.A. 24% gel. Case report: a 24-yearold normosystemic male patient came to the private dental office complaining of spontaneous pain and referred for endodontic treatment of tooth 17. The diagnosis was irreversible symptomatic pulpitis with indication for primary endodontic treatment. The main file chosen was the Reciproc® R25 M-wire (VDW), which during the instrumentation of the mesiobuccal canal suffered torsional fracture in the middle third, preventing continuity in the apical direction. Final considerations: the association of the conventional manual Hedströen file technique with the reciprocal reverse cutting technique of the Wave One® Gold Primary file and the use of E.D.T.A. 24% gel allowed the fractured file fragment to be overcome in the middle third of the mesiobuccal canal of tooth 17, promoting hermetic sealing, cleaning, modeling and satisfactory filling. (AU)

Effect of passive ultrasonic activation on microorganisms in primary root canal infection: a randomized clinical trial

Abstract Objective: This clinical study sought to evaluate the effectiveness of passive ultrasonic activation (PUA) in eliminating microorganisms in primary endodontic infection (PEI) after instrumentation of root canals using microbiological culture and checkerboard DNA-DNA hybridization. Methodology: Twenty root canals with PEI and apical periodontitis were selected. The root canals were instrumented and then randomly divided into 2 groups, according to the irrigation method: PUA and conventional needle irrigation (CNI). Microbiological samples were collected before instrumentation (S1), after instrumentation (S2) and after irrigation with 17% EDTA (S3). The samples were subjected to anaerobic culture technique and checkerboard DNA-DNA hybridization analysis. Results: A statistically significant difference was found between CNI (23.56%) and PUA (98.37%) regarding the median percentage values for culturable bacteria reduction (p<0.05). In the initial samples, the most frequently detected species was S. constellatus (50%), and after root canal treatment was E. faecalis (50%). Conclusion: Both treatments significantly decreased the number of bacterial species compared with the initial sample. However, no statistical difference in the total microbial load between PUA and CNI groups was detected. The number of cultivable anaerobic bacteria reduced significantly using PUA, and the bacterial composition and number of bacterial species after using either CNI or PUA was similar.

The Comparison of Different Irrigation Systems to Remove Calcium Hydroxide from the Root Canal: A Systematic Review and Meta-Analysis

Abstract Objective: To examine the effect of a variety of irrigation systems on the removal of root canal Ca (OH)2 residues through meta-analysis and systematic review. Material and Methods: A search of relevant articles was systematically performed on databases of Medline, PubMed, Cochrane Library, Embase, ISI, and Google Scholar published from 2013 to 2019. Electronic title management was carried out by EndNote X9 software. Searches were based on the main keywords of "Irrigation Systems", "Calcium Hydroxide"," Root Canal", "Self-adjusting File OR SAF", "Conventional Irrigation", "EndoVac System", "Ultrasonic Irrigation" and "YAG Laser". Results: The studies investigated were found to lack any standardization concerning the irrigation method used or the measurement of outcomes; for instance, different studies used 5 or 10 mL of 2.5% NaOCl, or 5 mL of 5.25% NaOCl, or 0.5 mL, 3 mL and 10 mL of 17% EDTA. Conclusion: The effective techniques for the removal of root canal Ca(OH)2 were PUI, and SAF approaches.

Reliability of Two Methods of Evaluation of the Apical Limit of Obturation of Root Canals of Primary Teeth: A Pilot Study

Abstract Objective: To verify the concordance in the evaluation of the apical limit of obturation (ALO) in filled root canals of primary teeth between digital and visual methods. Material and Methods: Twenty periapical radiographs of endodontically treated primary teeth were digitalized and evaluated by an endodontics specialist (E1), a PhD pediatric dentist (E2), and a MSc general dentist (E3). Calibrated evaluators (Kappa = 1.00) analysed the images in a light-isolated environment two times (D1 and D2) with a one-week interval between evaluations. ALO scores were categorized as overfilled, flush-filled and underfilled. Results: The intra-rater reliability between methods was 0.82 (D1) and 0.75 (D2) for E1, 0.93 (D1 and D2) for E2, and 0.94 (D1 and D2) for E3. Inter-rater reliability ranged from 0.71 (E1 × E3) and 1.00 (E1 × E2) for the visual method to 0.76 (E1 × E3) and 0.88 (E1 × E2) for the digital method. Spearman correlation coefficients showed a similar ranking among the evaluators. There was greater disagreement among the underfilled and ideal scores. For all evaluators, the digital method favoured the identification of the ideal score. Conclusion: Both methods are suitable for the determination of the ALO of filled primary teeth and can be used in clinical practice.

Does Endodontic Re-Treatment in Primary Teeth Increase the Functional Tooth Retention? A Clinical, Retrospective, University-Based Study

Objective: To investigate the longevity of endodontic treatments and the survival of endodontic re-treatments performed in primary teeth. Material and Methods: The sample included endodontic treatments and re-treatments conducted in anterior and posterior primary teeth without sedation or general anesthesia among children attending a university dental service. Information collected retrospectively from clinical records was used for analyzing data. The Kaplan-Meier estimator test was used to analyze the longevity and survival of endodontic treatment and re-treatments, respectively. Results: A total of 73 patients with endodontic therapy in primary teeth were included in the study, and 116 teeth were analyzed. After one year, the longevity of endodontic treatments performed on primary teeth was 65.74% with an annual failure rate (AFR) of 34.2%. From 47 endodontic treatment failures, 14 teeth (29.8%) were endodontically re-treated. When the endodontic re-treatment was considered as survival, the longevity of treatments reached 68.06% with 31.9% of AFR after one year of follow-up. There was a significant increase in functional tooth retention in those patients that received an endodontic re-treatment (p<0.001). Retreatment provided an additional mean survival time of 8.3 months. Conclusion: Endodontic treatments performed in primary teeth presented a limited longevity. Endodontic re-treatment is a more conservative alternative for endodontically treated primary teeth that have failed and significantly increase tooth retention.

Apical Debris Extrusion by Novel Endostar E5 Compared to Other Commercial Rotary Files: An in Vitro Study

Objective: To compare the amount of apical debris extrusion in samples instrumented by EndoStar E5, ProTaper Universal, and M-two rotary files. Material and Methods: Forty-five freshly extracted non-carious mandibular premolar teeth with single roots and single canals were acquired, and randomly divided into 3 groups (n=15). Samples in Groups 1, 2, and 3 were instrumented using EndoStar E5 (EE5), ProTaper Universal (PTU), and M-two (MTO) rotary file, respectively. Following instrumentation, the debris extruded was collected in pre-weighed Eppendorf tubes and stored in an incubator at 70°C for 5 days. Tubes containing the dry extruded debris were then weighed. One-way analysis of variance was applied to the weights obtained followed by Tukey's post hoc test for multiple comparison. Results: The mean debris extruded (mg) for the 3 groups were 1.23 (±0.72), 2.16 (±0.66), and 1.39 (±0.86) for EE5, PTU, and MTO respectively. Samples instrumented with PTU were associated with significantly higher debris extrusion (p<0.01) compared to EE5 and MTO. The groups EE5 and MTO did not differ in the amounts of debris extrusion (p>0.05). Conclusion: The novel EE5 and M-two rotary files result in less debris extrusion compared to PTU in mandibular premolars.

Polymicrobial Leakage and Retention of MTA and Portland Cement in a Model of Apexification

Abstract Objective: To evaluate the sealing capacity and retention of apical barriers made with mineral trioxide aggregate (MTA) and Portland cement (PC). Material and Methods: Fifty-six bovine incisors were sectioned 8 mm above and 12 mm below the cement-enamel junction. The root canal was enlarged with a diamond drill to create a standard 2.5 mm diameter opening. Apical sheets of 5 mm thickness were placed using white MTA-Angelus or white PC. Fifteen samples of each material were exposed to human saliva in a dual chamber apparatus and casting was evaluated at 30 days. Samples without apical barriers and fully sealed samples were used as positive and negative controls (n = 3), respectively. Data were analyzed by Fisher's exact test (p<0.05) after 3 periods: 1 to 10 days (P1); days 11 to 20 (P2); and days 21 to 30 (P3). Then, three 1 mm thick sections were obtained at the apical level of other root samples of each material (n = 10) and the push-out test was performed Results: The leakage rates in P1, P2 and P3 were 60%, 73.3% and 100% for the MTA; and 73.3%, 86.7% and 100% for CP, with no significant difference between materials, regardless of the period analyzed. There were no significant differences between the bond strengths for both cements (p>0.05) Conclusion: Mineral trioxide aggregate and Portland cement apical barriers presented similar sealing ability and bond strength values.

Influence of ThreeDifferent Instrumentation Techniques on the Incidence of Postoperative Pain After Endodontic Treatment

Objective:To evaluatethe influence of threedifferent instrumentation techniques on the incidence of postoperative pain after endodontic treatment.Material and Methods:Ninety permanent single rooted mandibular premolar with sign and symptoms of non-vital teethwere selected. Patients were randomly divided into three different groups according to the type of instrumentation:Group 1=Reciproc; Group 2=Twisted File incontinuousmotion and Group 3=WaveOne. Oburation was done with corresponding guttapercha points using zinc oxide eugenol sealer. The intensity of pain was recorded by the patient using visual analoguescale, after 2hr,6hr,12hr,48hr and 3days of completion of obturation.Data analysis was done using Wilcoxon signed-rankstest. The level of significance was set at 5%.Results:For Group 1 at 12 hours mean was 4.53 + 1.9 and median was 5. The mean value increased from 2 hours to 6 hours upto 12 hours and decreased after 48 hours till 3rd day. For Group 2 at 12 hours mean was 2.80 + 0.71 and median was 3.00. The mean value increased from 2 hours to 6 hours upto 12 hours and decreased after 48 hours till third day. For Group 3 at 12 hours mean was 4.77 + 1.81 and median was 5.00. Mean value increased from 2 hrupto 12 hr and decreased from 12 hours upto third day.At interval from 2-48 hours there is no significant difference seen between 3 groups and at 2 hours-3 days interval significant difference was seen in first group, but no significant results were seen between group 2 and group 3. There was no significant difference seen between all the groups at the interval of 6-12 hours (p>0.05). Conclusion:Pain score was less in case of Twisted File continuous motion technique while it was more in WaveOne and Reciproc technique (AU).

Evaluation of the efficacy of filling material removal and re-filling after different retreatment procedures

Abstract This study analyzed the influence of different retreatment protocols on amount of remaining filling material and amount of new sealer after endodontic retreatment. Forty mandibular molars with curved mesial roots were prepared with ProTaper Universal system, and filled with AH Plus sealer mixed with 0.1% rhodamine B and gutta-percha. After 7 days, the specimens were randomized according to the retreatment protocol (n = 10): ProTaper Retreatment System (PTR); PTR+Orange Oil (PTR+OO); PTR+Passive Ultrasonic Irrigation (PTR+PUI). No retreatment was performed in the control group (CG). After retreatment, the root canals were filled with AH Plus mixed with 0.1% fluorescein and gutta-percha. Samples were evaluated under confocal laser scanning microscopy and analyzed using Image J software. Data were analyzed using Kruskal-Wallis and Dunn tests (p < 0.05). Regarding presence of residual filling, the Kruskal-Wallis test indicated no differences among the different retreatment techniques in the perimeter and the isthmus analyses (p > 0.05); however, PTR+PUI was associated with a lesser amount of residual filling material in the canal area analysis (p < 0.05). In evaluating the new filling, the perimeter analysis showed a lesser amount of new endodontic sealer in the PTR group (p < 0.05). Moreover, the PTR+PUI group presented a significantly greater amount of new endodontic sealer in the canal area analysis (p < 0.05). There was no difference among groups in the isthmus analysis (p > 0.05). It can be concluded that PTR associated to PUI yielded better results in removing root canal filling material from the canal area. However, none of the protocols resulted in root walls completely free of remnants.

How biomechanics can affect the endodontic treated teeth and their restorative procedures?

Abstract: Endodontic treatment is a common dental procedure used for treating teeth which the pulp tissue has become irreversibly inflamed or necrotic as a result of the carious process or dental trauma. This procedure which involves mechanical and chemical preparation of root canal may affect several mechanical and physical properties of the tooth structure. The endodontic treatment can also influence the longevity of the rehabilitation of endodontically treated teeth and biomechanics during the oral function. For restoring endodontically treated teeth several factor and clinical decisions should be observed. The decision of the fiberglass post usage and the restorative materials are related to several factors such as the quantity and quality of remaining dental structure, presence of ferrule, post cementation length and final coronal restoration. In this review, the authors will address the effect of the endodontic treatment procedures on canal shape and mechanical properties of a tooth, and also discuss the parameters and the biomechanical principles of root canal treated teeth.

Comparación bacteriana de 30 piezas de alta velocidad antes y después de ser utilizadas en la facultad de odontología, Región Veracruz / Bacterial comparison of 30 high speed handpieces before and after being used at the school of dentistry, Veracruz Region

Introducción: en los procedimientos odontológicos se está expuestoa gran cantidad de microorganismos y las intervenciones clínicas provocan un contacto directo o indirecto con éstos, ya sea a través del instrumental, equipo odontológico contaminado con saliva, sangre, exudados, etcétera. Por esta razón debe tomarse en cuenta el tipo de contaminación de las piezas de mano por ser parte del equipo de uso cotidiano para realizar tratamientos odontológicos. Objetivos generales:Determinar la carga bacteriana en las piezas de alta velocidad antes y después de su uso en diferentes clínicas de la Facultad de Odontologíade la UV Región Veracruz. Metodología: Investigación transversal, descriptiva y observacional. Material y métodos: Se seleccionaron al azar 30 piezas de mano de los estudiantes de la Universidad Veracruzana Facultad de Odontología Región Veracruz, a las cuales se tomó una muestra con un hisopo de algodón antes y después de su uso en la práctica dental. Se realizaron cultivos con las muestras obtenidas que se observaron durante tres días seguidos bajo microscopio para comprobar la presencia de colonias bacterianas. Resultados: De las30 piezas antes de ser utilizadas se detectó Bacillus grampositivos en24 por ciento de las muestras; en 20 por ciento Bacillus gramnegativos, en 6 por ciento Streptobacillus gram-positivos; en 20 por ciento Staphylococcus grampositivos; en 3 por ciento Cocobacillus gramnegativos y en 22 por ciento Actinomyces gramnegativos. El restante 2 por ciento no reveló unidades formadoras de colonias (UFC). En un segundo muestreo, 33 por ciento desarrolló Bacillus grampositivos, 10 por cientoBacillus gramnegativos, 20 por ciento adquirió Sthapylococcus grampositivos, 3 por ciento Sthapylococcus gramnegativo y 34 por ciento no reveló UFC. Conclusión:En el primer muestreo se detectaron microorganismos en 98% de laspiezas de mano, mientras que en el segundo muestreo 66% se contaminócon microorganismos y en 34% no se observó contaminación.

Introduction: dental activity is exposed to a lot of microorganisms,and clinical interventions have a direct or indirect contact with them.Whether through the instruments, dental equipment contaminatedwith saliva, blood, etc; so you should take into account the type ofcontamination of handpieces for being the most widely used equipmentfor dental treatment. General Objectives: Determine the bacterialload in high-speed parts before and after being used in diff erentclinical uses in Dentistry School at UV, Veracruz. Methodology:Cross-sectional, descriptive and observational research. Materialand methods: 30 pieces of students from the Universidad VeracruzanaSchool of Dentistry, Veracruz region, which a sample was takenwith a swab to pieces before and after use in dental practice wererandomly selected. Cultures with samples obtained observedduring three days in a row microscope to determine the presenceof bacterial colonies were made. Results: Of the 30 pieces beforebeing used 24% of Bacillus Gram-positive samples were found; 20%Bacillus Gram-negative, Gram-positive Streptobacillus 6%; 20%Gram-positive Staphylococcus, 3% developed Coccobacillus Gramnegativeand 22% Gram negative Actinomyces. The remaining 2%no colony forming units development (UFC). In a second sampling;33% developed Bacillus Gram-positive, Gram-negative Bacillus10%, 20% obtained Sthapylococcus Gram-positive, Gram-negativeSthapylococcus 3% and 34% did not develop colony forming unit(CFU). Conclusion: In the first sampling 98% of the pieces were microorganism growth, while in the second 66% and the presence ofmicroorganisms obtained 34% no development.

Diversidade bacteriana nas infecções endodônticas primárias e secundárias/persistentes através da técnica de Checkerboard DNA-DNA Hybridization / Bacterial diversity in primary and secondary/persistent endodontic infections by Checkerboard DNA-DNA Hybridization Technique

Introdução: os métodos moleculares de diagnóstico apresentam como uma das principais vantagens a detecção de microrganismos por meio do DNA bacteriano, levando a uma caracterização microbiana mais acurada. Objetivo: o presente estudo visou investigar a diversidade bacteriana presente nas infecções endodônticas primárias e secundárias/persistentes, comparando o perfil das comunidades microbianas existentes antes e após a terapia endodôntica. Métodos: as amostras microbiológicas foram coletadas antes (T1) e após terapia endodôntica (T2), utilizando cone de papel estéril/apirogênico em dentes com infecções endodônticas primárias (n = 10) e secundárias / persistentes (n = 10). A presença e os níveis de 40 espécies bacterianas nas infecções endodônticas foram investigados por meio da técnica de Checkerboard DNA-DNA Hybridization. Resultados: nas infecções endodônticas primárias em T1, as espécies encontradas em maiores níveis foram P. micra, F. nucleatum sp. nucleatum, S. constellatus, P. gingivalis, G. morbillorum, P. endodontalis, T. denticola, P. acnes, S. gordonii, S. mitis, V. parvula e C. rectus. Em T2, as bactérias mais encontradas foram P. micra, S. oralis e P. acnes. Nas infecções endodônticas secundárias em T1, as espécies mais frequentemente encontradas foram P. acnes, P. micra, S. constellatus, G. morbillorum, C. rectus, A. naeslundii, S. mitis e S. oralis. Em T2, as espécies mais encontradas foram Enterococcus faecalis e Propionibacterium acnes. Conclusão: o presente estudo confirmou comunidades microbianas distintas em infecções endodônticas primárias e secundárias. Além disso, os procedimentos clínicos endodônticos mostraram-se eficazes na redução significativa da prevalência, dos níveis de detecção e na diversidade bacteriana.

Capacidade de selamento e penetração intratubular do MTA Fillapex e do AH Plus em dentes humanos / Sealing ability and penetration intratubular MTA Fillapex and AH Plus in human teeth

Introdução: O MTA é um importante material de uso na odontologia, com boas propriedades biológicas. As respostas experimentais aos cimentos endodônticos que utilizam este composto no selamento e preenchimento do sistema de canais radiculares, aliados a uma boa instrumentação e limpeza, podem ser importantes no processo de reparo periapical. Objetivo: Avaliar in vitro a profundidade de penetração de dois diferentes cimentos endodônticos nos túbulos dentinários e a infiltração bacteriana em obturações com os cimentos AH Plus e MTA Fillapex. Material e método: 34 pré-molares monorradiculados humanos foram selecionados, suas coroas removidas e suas raízes padronizadas em 16 mm, a seguir foram, então, divididos aleatoriamente em dois grupos de 15 espécimes e instrumentados com o sistema rotatório Pro Taper. Um grupo foi obturado com o cimento AH Plus (Grupo AH) e outro com MTA Fillapex (Grupo FI). Nestes grupos, avaliaram-se a infiltração coronária de bactérias para Enterococcus Faecalis e a profundidade de penetração nos túbulos dentinários. Para a aferição da infiltração bacteriana, usou-se o teste exato de Fisher; para a penetração intratubular, usou-se o teste-t. Resultado: Para a infiltração bacteriana, considerando o número de amostras infiltradas para AH e MTA Fillapex, houve diferença estatística significativa (p=0,0341). Na avaliação da penetração intratubular, a diferença entre os dois grupos de cimentos foi considerada estatisticamente significativa (p=0,0006). Conclusão: Ambos os cimentos apresentaram infiltração bacteriana, sendo que o MTA Fillapex teve pior desempenho. A capacidade de penetração nos túbulos dentinários do AH Plus foi significativamente maior que a do MTA Fillapex.

Introduction: The MTA is an important use in dentistry material with good biological properties. The experimental responses to sealers using this compound in the sealing and filling of the root canal system, combined with a good instrumentation and cleaning, may be important in the periapical healing process. Objective: To evaluate in vitro penetration depth of two different sealers in dentinal tubules and bacterial infiltration in fillings with AH Plus and MTA Fillapex cements. Material and method: 34 premolars human monorradiculados were selected, their removed and their standardized root crowns in 16mm, after then randomly divided into two groups of 15 specimens, and instrumented with rotary system Pro Taper. One group was obturated with cement AH Plus (group HA) and another MTA Fillapex (FI Group). These groups are evaluated for coronary infiltration of bacteria Enterococcus faecalis and the depth of penetration in the dentinal tubules. For the measurement of bacterial infiltration used Fisher's exact test for Intratubular penetration we used the t-test. Result: For bacterial infiltration, considering the number of infiltrated samples AH and MTA Fillapex, there was a statistically significant difference (p = 0.0341). In the evaluation of intratubular penetration, the difference between the two groups of cement was statistically significant (p = 0.0006). Conclusion: Both cements showed bacterial infiltration and the MTA Fillapex had worse performance, capabilities to enter the dentinal tubules AH Plus was significantly higher than the MTA Fillapex.