An artificial intelligence grading system of apical periodontitis in cone-beam computed tomography data.

OBJECTIVES: In order to assist junior doctors in better diagnosing apical periodontitis (AP), an artificial intelligence AP grading system was developed based on deep learning (DL) and its reliability and accuracy were evaluated. METHODS: 120 cone-beam computed tomography (CBCT) images were selected to construct a classification dataset with four categories, which were divided by CBCT periapical index (CBCTPAI), including normal periapical tissue, CBCTPAI 1-2, CBCTPAI 3-5 and young permanent teeth. Three classic algorithms (ResNet50/101/152) as well as one self-invented algorithm (PAINet) were compared with each other. PAINet were also compared with two recent Transformer-based models and three attention models. Their performance was evaluated by accuracy, precision, recall, balanced F score (F1-score) and the area under the macro-average receiver operating curve (AUC). Reliability was evaluated by Cohen's kappa ​​to compare the consistency of model predicted labels with expert opinions. RESULTS: PAINet performed best among the four algorithms. The accuracy, precision, recall, F1-score and AUC on the test set were 0.9333, 0.9415, 0.9333, 0.9336 and 0.9972, respectively. Cohen's kappa was 0.911, which represented almost perfect consistency. CONCLUSIONS: PAINet can accurately distinguish between normal periapical tissues, CBCTPAI 1-2, CBCTPAI 3-5 and young permanent teeth. Its results were highly consistent with expert opinions. It can help junior doctors diagnose and score AP, reducing the burden. It can also be promoted in areas where experts are lacking to provide professional diagnostic opinions.

MTA as modulator of periapical tissue healing in rat molar: A histological study.

Background: Periapical surgery has been suggested as a treatment option for teeth with periapical lesions when those lesions continue despite receiving root canal therapy. Since sealing the apical region is the operation's primary goal, the choice of the root-end filling material affects how the surgery turns out. The retrofilling materials Zinc Oxide Eugenol (ZOE) and Mineral trioxide aggregate (MTA) are both known to have antibacterial characteristics. The purpose of this study is to determine how MTA affects as a Modulator of Periapical Tissue Healing through histological examination in Rat Molar. Methods: A dental fissure bur measuring 0.7 mm is used to remove the buccal root apex from the buccal alveolar bone's surface, creating the cavity. One of the following is placed within each cavity: Group 1: MTA, Group 2: ZOE. For each material series, six samples were used. We classified the healing outcomes for each MTA and ZOE retrograde filling material into three groups based on histological analysis: the amount of newly generated bone, the number of fibroblasts, and the infiltration of neutrophils into the surgical site. Results: On the 6th day of examination, fibroblasts were seen in the area around the wound. A significant inflammatory response, including neutrophil infiltration, was seen around the ZOE after retrograde filling. On the 16th day, the new alveolar bone structure showed a slight increase. After filling the MTA on the 6th day of examination, the immediate inflammatory response was insignificant. Neutrophils were observed to enter the region surrounding the retrofilled MTA, and a small number of osteoclasts were observed to be resorbing bone. Around the wound site, fibroblasts can also be detected. On the 16th day, unlike ZOE, a lot of new bone grows close to this material. Conclusion: MTA has the ability to modulate periapical healing in rat molar.

Identification of root canal microbiota profiles of periapical tissue diseases using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

OBJECTIVES: The purpose of this study was to identify microorganisms isolated from various periapical tissue diseases using Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) and classify them via an unsupervised machine learning approach. METHODS: A total of 150 patients with various apical conditions and teeth in need of endodontic retreatment were divided into five groups, including Retreatment, Acute Apical Abscess, Chronic Apical Abscess, Acute Apical Periodontitis, and Chronic Apical Periodontitis. Samples were collected from root canals using paper points after agitating with a #10 K file then microorganisms were identified using MALDI-TOF-MS. Data were analyzed using a hierarchical clustering method. Quadruple clusters and dendrograms were formed according to similarities and dissimilarities. RESULTS: A total of 80 species were identified representative of six different phyla. The most similar microorganism species identified were: ''Enterococcus faecalis'' between 21 and 23-year-old female cases in Retreatment group; ''Lactobacillus rhamnosus'' between 20 and 18-year-old male cases in Symptomatic Apical Abscess cases; ''Lactobacillus paracasei'' between 26 and 40-year-old male cases in Asymptomatic Apical Abscess cases; ''Enterococcus faecalis'' between 48 and 50-year-old female cases in Symptomatic Apical Periodontitis cases; ''Lactobacillus rhamnosus'' between 48 and 60-year-old male cases in Asymptomatic Apical Periodontitis cases. CONCLUSIONS: MALDI-TOF MS can be considered a fast and high-throughput screening technique for microbial species identification in endodontics. Thus, it will provide valuable data for future research designs regarding periapical tissue diseases. As the MALDI-TOF MS database expands and comprehensive data becomes available, the relationship between microbial profiles and disease progression will become increasingly apparent.

Evaluation of histogram equalization and contrast limited adaptive histogram equalization effect on image quality and fractal dimensions of digital periapical radiographs.

OBJECTIVES: This study aims to evaluate the effects of histogram equalization (HE) and contrast limited adaptive histogram equalization (CLAHE) on periapical images and fractal dimensions in the periapical region. METHODS: In this cross-sectional study, digital periapical images were selected from the archive of Dentistry School of Isfahan University of Medical Sciences. The radiographs were taken from mandibular and maxillary anterior single root teeth with healthy root and periodontium. After applying HE and CLAHE algorithms to images, two radiologists evaluated the quality of apex detection from using a 5-point Likert scale (from 5 for very good image quality to 1 for very bad image quality). Afterward, all the images were imported to the ImageJ application, and the region of interest (ROI) was specified as the region between the two central incisors. The fractal box-counting method was used to determine fractal dimensions (FD) values. Nonparametric Wilcoxon-Friedman test, Intraclass Correlation Coefficient test, T-test, and Pair T-test were performed as statistical analysis (α = 0.05). RESULTS: Fifty-three radiographs were analyzed and the image quality assessments were significantly different between raw images and images after performing HE, CLAHE (p value < 0.001), and using CLAHE algorithm significantly increases image quality assessments more than HE (p value = 0.009). There was a significant difference in FD values for images after applying CLAHE and HE compared to raw images (p value < 0.001), and HE decreased the FD value significantly more than CLAHE (p value = 0.019). CONCLUSIONS: Employing CLAHE and HE algorithm via OpenCV python library improves the periapical image quality, which is more significant using the CLAHE algorithm. Moreover, applying CLAHE and HE reduces trabecular bone structure detection and FD values in periapical images, especially in HE.

Clinical Approach of Extensive Periapical Lesion with Periradicular Regenerative Surgery: A Case Report with 7 Year Follow Up

The aim of this study is to report a case of two maxillary incisors with chronic apical abscess and through-and-through lesion submitted to periradicular regenerative surgery, with clinical follow-ups and evaluation through cone-beam computerized tomography for 7 years. In the presentation, there was a persistent sinus tract in the palate and sensibility to touch at the apical region of the central and left lateral maxillary incisors. The initial tomography revealed the presence of an extensive radiolucent area in the apical third of the referred teeth, with loss of the buccal and palatal cortic es. For the treatment, a periradicular regenerative surgery was performed, an association of endodontic surgery with Guided Tissue Regeneration technique, using bovine bone xenograft and bioabsorbable membrane. The clinical and radiographic evaluations, including cone-beam computerized tomography, at seven years postoperatively, showed absence of symptomatology and sinus tract, probing depth within normal standards and apical bone neoformation.

El objetivo de este estudio fue reportar un caso de dos incisivos superiores con absceso apical crónico y lesión transversal sometidos a cirugía regenerativa perirradicular, con seguimiento clínico y evaluación mediante tomografía computarizada de haz cónico durante 7 años. En la presentación, había un trayecto sinusal persistente en el paladar y sensibilidad al tacto en la región apical de los incisivos maxilares laterales central y lateral izquierdo. La tomografía inicial reveló la presencia de una extensa zona radiolúcida en el tercio apical de los dientes referidos, con pérdida de las cortezas bucal y palatina. Para el tratamiento se realizó una cirugía regenerativa perirradicular, asociación de cirugía endodóntica con técnica de Regeneración Tisular Guiada, utilizando xenoinjerto óseo bovino y membrana bioabsorbible. Las evaluaciones clínicas y radiográficas, incluida la tomografía computarizada de haz cónico, a los siete años del posoperatorio, mostraron ausencia de sintomatología y tracto sinusal, profundidad de sondaje dentro de los estándares normales y neoformación ósea apical.

Impact of Sodium Hypochlorite on Organic Tissue Dissolution in the Periapical Region of Immature Permanent Teeth: An Ex Vivo Study.

INTRODUCTION: The purpose of this study was to evaluate the impact of different sodium hypochlorite (NaOCl) irrigation protocols on organic tissue dissolution in the periapical region of simulated immature permanent teeth. METHODS: Eight single-rooted premolars and 48 samples of porcine palatal mucosa were used. Acrylic resin prototypes were constructed, placing the tissue in close contact with the dental apices. Specimens were then divided into 6 groups (n = 8): 2 control groups of normal saline irrigation with (NS/WA) or without (NS/NA) ultrasonic activation and 4 experimental groups of 1.5% and 2.5% NaOCl irrigation with (NaOCl 1.5%/WA and NaOCl 2.5%/WA) or without (NaOCl 1.5%/NA and NaOCl 2.5%/NA) activation. Root canals were irrigated with 20 mL of the solution for 5 minutes distributed over 4 irrigation cycles. In each cycle, after irrigation, the solution was either kept stagnant or activated for 30 seconds and then replaced. Specimens were weighed on a precision balance before and after the irrigation protocols. Tissue dissolution was measured by the difference between the initial and final weights. One-way analysis of variance was applied followed by the Tukey honestly significant difference test (α = 0.05). RESULTS: The NS/NA and NS/WA groups had mean weight reductions similar to the 1.5% NaOCl/NA group (P > .05) and lower than the others (P < .05). The 2.5% NaOCl/NA and 2.5% NaOCl/WA groups had the highest mean weight loss (P < .05), whereas the 1.5% NaOCl/WA group had intermediate values (P < .05). CONCLUSIONS: Periapical tissue dissolution occurred in all groups, with a greater impact observed with 2.5% NaOCl with or without ultrasonic activation.

Effect of endodontic sealer in young molars treated by undergraduate students - a randomized clinical trial

Abstract The progression of caries in permanent molar teeth of young patients, frequently result in endodontic treatment. This randomized blinded clinical trial assessed the effect of two endodontic sealers (Sealer 26 and AH Plus) on the incidence of pain and apical repair after endodontic treatment of young molar teeth, and secondly identify factors associated with the outcomes. Endodontic treatment was performed by undergraduate students in molar teeth (n=69) of young patients (n=54) at the Endodontic and Restorative Public Extension Clinic Service. Protaper Next was used and the endodontic sealers were allocated which were restored with direct composite resin. Two primary clinical outcomes - apical repair and postoperative pain, were assessed after 12 and 24 months for blinded operators. Description of incidence rates and mixed-model regression using Generalized Estimation Equations (GEE). After 2 years 69 molar teeth of 54 patients were evaluated. No effect of the endodontic sealer was observed irrespective of period of evaluation. Apical repair incidences and asymptomatic teeth were, respectively, 90.5 and 89.3, 96.8 and 90.0% during 1 and 2 years of follow-up. Failed apical repair was associated with unsatisfactory pulpectomy (p=0.003) and periapical conditions (p=0.007) as well as their interaction (p=0.016). None of these independent variables was able to predict the occurrence of pain in both periods. Prognosis of apical repair is dependent on the initial conditions. Endodontic treatment of young molars associated with composite resin restorations performed by undergraduate students have satisfactory results after 2 years and was effective to prevent the risk of permanent teeth loss.

Resumo A rápida progressão das lesões de cárie nos dentes molares permanentes de pacientes jovens, frequentemente resulta no tratamento endodôntico. Este ensaio clinico randomizado cego avaliou o efeito de dois cimentos endodônticos (Sealer 26 e AH Plus) na incidência de dor e reparo apical após tratamento endodôntico de dentes molares jovens e identificar fatores associados aos desfechos do tratamento. O tratamento endodôntico foi realizado por estudantes de graduação em dentes molares permanentes (n=69) de pacientes jovens (n=54) na Clínica de Extensão Endodôntica e Restauradora da Universidade Federal de Uberlândia, Brasil. Protaper Next foi usado e os dois cimentos foram distribuídos aleatoriamente nas amostras, as quais foram restauradas com resina composta direta. Dois desfechos clínicos primários - reparo apical e dor pós-operatória foram avaliados após 12 e 24 meses por operadores de forma cega. Análise longitudinal dos dados incluiu a descrição das taxas de incidência e modelo de regressão misto usando Equações de Estimativa Generalizadas (GEE). As incidências (%) do reparo apical e dos dentes assintomáticos foram respectivamente 90,5/89,3 e 96,8/90,0 nos períodos de 1 e 2 anos de acompanhamento. Ausência de reparo apical foi associada com pulpectomia insatisfatória (p=0,003) e condições periapicais (p=0,007), bem como sua interação (p=0,016). Nenhuma dessas variáveis independentes foi capaz de prever a ocorrência de dor nos períodos de acompanhamento. O tratamento endodôntico mostrou resultados satisfatórios após 2 anos. O prognóstico do reparo apical depende das condições iniciais. Nenhum efeito do cimento endodôntico foi observado. O tratamento endodôntico de molares jovens associado com restaurações em resina composta realizado por estudantes de graduação tem um papel relevante na redução do risco de perda do dente permanente.

Histological Evaluation of Periapical Tissues after Root Canal Treatment with or without Coronal Seal in Dogs for Six Months.

Introduction: Preventing recontamination of the obturated root canal is important for successful root canal treatment (RCT). The main purpose of this study was assessing the histological health of periradicular tissue in obturated root canals with or without coronal seal between two and six months. Methods and Materials: Sixty roots from five dogs with vital pulps were randomly assigned to one of the following five groups (n=12): Group 1, RCT and six months oral exposure; Group 2, RCT and immediate amalgam restoration; Group 3, RCT and amalgam restoration after two months exposure to the oral cavity; Group 4, RCT and amalgam restoration after four months exposure to the oral cavity; Group 5, RCT with two months exposure to oral cavity. The teeth were prepared and filled with gutta-percha and sealer using lateral condensation technique. Two intact root canals of each animal were regarded as the negative control group (n=10), and the two root canals exposed to the oral cavity constituted the positive one (n=10). After six months the animals were euthanized. The upper and lower jaws were removed and submitted for histological processing. Longitudinal sections were obtained from each root. After staining the sections, periradicular regions were examined histologically under light microscope. The Kruskal-Wallis and Mann-Whitney tests was used to analyze the data (P<0.05). Results: The results showed a significant difference between all groups (P<0.05). The negative control group was free of any inflammation. Two-by-two comparison revealed that the positive control group, Group 1 and Group 4 displayed the most intense inflammation. Groups 2, 3 and 5 showed similar results without developing any significant inflammation. Conclusion: Based upon the findings of this animal study, it can be recommended that the obturated root canals which are exposed to oral cavity for around four months or more should be retreated before crown restoration.

Clinical practice guidelines for the surgical endodontic management of post-treatment periapical disease / Guía de práctica clínica para el manejo quirúrgico en endodoncia de la enfermedad periapical postratamiento

ABSTRACT Introduction: in Colombia, persisting post-endodontic disease has been reported by up to 45%, validating the use of secondary alternative therapies, like endodontic microsurgery (EM). The aim of this study was to systematically-and with reliable scientific evidence-develop de Novo Clinical Practice Guidelines for the surgical endodontic management of post-treatment periapical disease (PPD), with more accurate recommendations for therapeutic decisions and preferences consulted with both practitioners and patients. Method: the guidelines developers team identified EM as a topic in the literature and established the scope, objective, questions, and outcomes, which were analyzed using the scientific evidence reported in secondary or primary clinical studies. A first screening identified titles and abstracts for each question asked. The validity of the selected studies was quantified with tools like AMSTAR or SIGN. Finally, the strength of recommendations and the quality of evidence were confirmed with GRADE. Results: concepts like PPD, EM indication, use of local anesthetics, antibiotics and presurgical anti-inflammatory drugs, effect of magnification, implementation of cone beam computed tomography, hemostasis, retrograde filling, and control time were integrated, supporting each topic with relevant evidence, experts' recommendations, and even good practice points. Conclusions: this document is considered a tool with sufficient evidence for clinical decision-making in EM.

RESUMEN Introducción: en Colombia, la persistencia de enfermedad posendodoncia ha sido reportada hasta en un 45%, lo cual justifica propuestas terapéuticas secundarias, como la microcirugía endodóntica (ME). El objetivo del presente estudio consistió en desarrollar sistemáticamente, y con evidencia científica confiable, una Guía de Práctica Clínica de Novo para el manejo quirúrgico en endodoncia de la enfermedad periapical postratamiento (EPP), con las recomendaciones más acertadas frente a decisiones y preferencias terapéuticas consultadas a profesionales y pacientes. Método: el grupo desarrollador de la guía identificó el tópico ME y estableció el alcance, el objetivo, las preguntas y los desenlaces, analizados mediante la evidencia científica registrada a partir de estudios clínicos secundarios o primarios. Un primer tamizaje identificó títulos y resúmenes para cada pregunta formulada. La validez de los estudios seleccionados se cuantificó con las herramientas AMSTAR o SIGN. Finalmente, la fuerza de las recomendaciones y la calidad de la evidencia se constataron con la herramienta GRADE. Resultados: se integraron los conceptos de EPP, indicación de la ME, uso de anestésicos locales, antibióticos y antinflamatorios prequirúrgicos, efecto de la magnificación, implementación de la tomografía computarizada de haz cónico, hemostasia, materiales de retroobturación y el tiempo de control, sustentando cada tópico con la evidencia, la recomendación de los expertos y en ocasiones con las premisas de las buenas prácticas. Conclusiones: el presente documento se considera una herramienta con suficiente evidencia para la toma de decisiones clínicas en ME.

The influence of apical extent of root canal obturation on endodontic therapy outcome: a systematic review.

OBJECTIVES: This systematic review (SR) aimed to investigate the influence of obturation extent on the final outcome of root canal treatment (RCT), by answering the question "among patients requiring RCT on fully formed permanent teeth, is there an association between obturation extent and the final treatment outcome?" MATERIALS AND METHODS: Five electronic databases and three gray literature searches were performed. Observational studies investigating the association between obturation extent and RCT outcome in fully formed permanent teeth with a minimum follow-up of 12 months were included. We evaluated the risk of bias (RoB) in with MAStARI for cohort studies. The overall quality of the evidence was assessed with the GRADE-tool. RESULTS: Twenty-two studies were included, 2 had high RoB, 7 moderate RoB, and 13 low RoB. Underextended obturation demonstrated increased odds of an unfavorable outcome in seven studies, in which the odds varied between 6.94 (95%CI 2.20-21.87) and 1.73 (95%CI 1.02-2.95). Overextended obturation also demonstrated this association in four studies, with odds varying from 1.90 (95%CI 1.23-2.94) to 23.00 (95%CI 5.58-94.75). Due to heterogeneity and the very low level of evidence found in the GRADE analysis, the results from this SR should be interpreted with caution. CONCLUSIONS: Obturation extent seems to influence RCT outcome; overextended and underextended obturations showed higher chance of association with less favorable outcomes than adequate obturation; however, this association was not categorically supported. CLINICAL RELEVANCE: This SR provides information about obturation extent influence on RCT outcome and guides clinicians to make evidence-based decisions during endodontic practice.

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

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

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

A Simplified and Systematic Method to Isolate, Culture, and Characterize Multiple Types of Human Dental Stem Cells from a Single Tooth.

This chapter describes a simplified method that allows the systematic isolation of multiple types of dental stem cells such as dental pulp stem cells (DPSC), periodontal ligament stem cells (PDLSC), and stem cells of the apical papilla (SCAP) from a single tooth. Of specific interest is the modified laboratory approach to harvest/retrieve the dental pulp tissue by minimizing trauma to DPSC by continuous irrigation, reduction of frictional heat from the bur rotation, and reduction of the bur contact time with the dentin. Also, the use of a chisel and a mallet will maximize the number of live DPSC for culture. Steps demonstrating the potential for multiple cell differentiation lineages of each type of dental stem cell into either osteocytes, adipocytes, or chondrocytes are described. Flow cytometry, with a detailed strategy for cell gating and analysis, is described to verify characteristic markers of human mesenchymal multipotent stromal cells (MSC) from DPSC, PDLSC, or SCAP for subsequent experiments in cell therapy and in tissue engineering. Overall, this method can be adapted to any laboratory with a general setup for cell culture experiments.

Dose optimization for assessment of periodontal structures in cone beam CT examinations.

OBJECTIVES: To investigate the relationship between dose and image quality for a dedicated dental CBCT scanner using different scanning protocols and to set up an optimal imaging protocol for assessment of periodontal structures. METHODS: Radiation dose and image quality measurements were made using 3D Accuitomo 170 (J. Morita, Kyoto, Japan) dental CBCT scanner. The SedentexCT IQ phantom was used to investigate the relationship between contrast-to-noise ratio (CNR) and dose-area product. Subjective image quality assessment was achieved using a small adult skull phantom for the same range of exposure settings. Five independent observers assessed the images for three anatomical landmarks using a three-point visual grade analysis. RESULTS: When correlating the CNR of each scanning protocol to the exposure parameters used to obtain it, CNR decreased as these parameters decreased, especially current-exposure time product. When correlating to subjective image quality, the CNR level remained acceptable when 5 mA and 17.5 s or greater was selected and 80 kV could be used without compromising the CNR. CONCLUSIONS: For a dedicated CBCT unit, changing the rotation angle from 360° to 180° degrades image quality. By altering tube potential and current for the 360° rotation protocol, assessment of periodontal structures can be performed with a smaller dose without substantially affecting visualization.

Descriptive study of apical periodontitis detected in Cone Beam Computed Tomography scans / Estudo descritivo de periodontite periapical detectada em exames de Tomografia Computadorizada de Feixe Cônico

ABSTRACT Objective: To perform a descriptive study in order to evaluate apical periodontitis in endodontically treated teeth using cone beam computed tomography. Methods: Eighty-six exams presenting at least one apical periodontitis were selected and divided into two groups: 1 for the mandible and 2 for the maxilla. All the exams were done using the same cone beam computed tomography with standard acquisition settings. All the images were processed and manipulated using the same software. Then the lesions were classified according to the periapical index, but not considering the expansion and/or destruction of cortical. Results: 127 mandibular teeth and 180 maxillary teeth exhibited apical periodontitis with an average size of 0.49 mm in the mandible and 0.75 mm in the maxilla. It was found that the lower pre-molars were the teeth most affected. Lesions identified with scores between 0 and 1 correspond to 83.47% of the lesions in the mandible and 78.89% in the maxilla, and 55.12% of endodontically treated lower teeth and 50% of upper teeth presented no lesion recurrence or lesions under repair. Conclusion: There was a predominance of small apical periodontitis, the pre-molars being the teeth most affected.

RESUMO Objetivo: Realizar um estudo descritivo para avaliar periodontites periapicais em dentes com tratamento endodôntico em tomografia computadorizada de feixe cônico. Métodos: Oitenta e seis exames que apresentaram pelo menos uma periodontite periapical foram selecionados e separados em dois grupos: 1 para a mandíbula, e 2 para a maxila. Todos os exames foram realizados na tomografia computadorizada de feixe cônico com os mesmos protocolos de aquisição, e o mesmo software de avaliação e de mensuração. As lesões foram classificadas de acordo com o índice periapical, mas sem considerar a expansão do osso cortical e/ou destruição. Resultados: Cento e vinte sete dentes inferiores e 180 dentes superiores apresentaram periodontites periapicais com tamanho médio de 0,49 mm na mandíbula e de 0,75 mm na maxila. Observou-se que os pré-molares inferiores foram os dentes mais acometidos. Lesões identificadas entre os escores 0 e 1 corresponderam a 83,47% das lesões na mandíbula e 78,89% na maxila, sendo que 55,12% dos dentes tratados endodonticamente inferiores e 50% superiores não apresentaram lesões reincidentes ou em fase de reparação. Conclusão: Houve um predomínio de periodontites periapicais pequenas, sendo os pré-molares os dentes mais acometidos por estas lesões.

Radicular Perforation Repair with Mineral Trioxide Aggregate: A Case Report with 10-Year Follow-up.

BACKGROUND: Iatrogenic complications such as accidental perforation of the root or the floor of the pulp chamber may occur. CASE REPORT: Patient was referred for root canal retreatment of the mandibular left second molar with periapical lesion evidenced through radiographic examination. During post removal, iatrogenic perforation occurred at the mesial face of the distal root. After clinical localization of the perforation and bleeding control, MTA was applied. In a second appointment, the root canal filling was removed and the chemical-surgical retreatment of the canals was performed, followed by the obturation with gutta-percha and sealer. Patient returned after three days reporting no pain. After 6 months, 3, 7 and 10 years of follow-up. CONCLUSION: Absence of pain, normal periodontal probing and lack of radiolucent area at the region of perforation and the periapices were detected, which evidenced the successful repair of the tooth.

Frequency of pulpal and periapical disorders prior to orthodontic treatment / Frecuencia de los trastornos pulpares y periapicales antes del tratamiento de ortodoncia

Introduction and objective: Orthodontic forces can aggravate a pre-existent pulpal condition. The aim of the present study was to determine the frequency of pulpal disorders in patients prior to orthodontic treatment. Materials and methods: Transversal study. 37 patients (19 female, 18 male) who met the following criteria were included: Patients with permanent dentition (including second molars) with full root formation, with a complete set of periapical radiographs, and no previous orthodontic treatment. Patients using pacemakers or with history of previous orthodontic treatment were excluded. Clinical testing of pulpal vitality and sensitivity, as well as periapical condition, was performed. Relative and absolute frequencies for pulpal and periapical diagnoses were described. Also, stratification by gender, age, arch, and area was implemented. Results: 981 teeth were analyzed, 48.6% of the teeth showed pulpal or periapical disorders (477/981). Pulpless teeth were found mostly in female patients (72.2%), patients with 41 years of age on average (26%), and patients exhibiting three or more restorations (2.8%). 20.5% teeth were affected with periapical conditions (39/942). The first left maxillary molar showed the highest frequency of pulpal and periapical disorders. 73.5% exhibited poorly-performed obturation or condensation techniques from the 34 affected teeth (25/34). 74.3% of affected teeth were in the maxilla and 64.1% were in the posterior area of the mouth. Conclusion: A detail clinical and radiological examination of pulpal and periapical status should be performed before the onset of orthodontic treatment.

Resumen Introducción y objetivo: Las fuerzas de ortodoncia pueden agravar una condición pulpar preexistente. El objetivo del presente estudio fue determinar la frecuencia de los trastornos pulpares en los pacientes antes del tratamiento de ortodoncia. Materiales y métodos: Estudio transversal. 37 pacientes (19 mujeres, 18 hombres) que se reunieron se incluyeron los siguientes criterios: Los pacientes con dentición permanente (incluyendo segundos molares) con la formación de raíces por completo, con un juego completo de radiografías periapicales, y ningún tratamiento ortodóncico anterior. Se excluyeron los pacientes que utilizan marcapasos o con antecedentes de tratamiento ortodóncico anterior. Las pruebas clínicas de vitalidad y sensibilidad pulpar, así como la condición periapical, se llevó a cabo. Se describen las frecuencias relativas y absolutas para diagnósticos pulpares y periapicales. Además, se llevó a cabo la estratificación por sexo, edad, arco, y el área. Resultados: Se analizaron 981 dientes, 48,6% de los dientes mostraron trastornos pulpares o periapicales (477/981). Los dientes sin pulpa se encuentran sobre todo en pacientes de sexo femenino (72,2%), los pacientes con 41 años de edad en promedio (26%), y los pacientes que presentan tres o más restauraciones (2,8%). El 20,5% de los dientes se vieron afectados con condiciones periapicales (39/942). El primer molar superior izquierdo mostró la mayor frecuencia de trastornos pulpares y periapicales. 73,5% exhibió técnicas de obturación, o de condensación realizados pobremente de los dientes afectados (25/34). 74,3% de los dientes afectados se encontraban en el maxilar y el 64,1% se encontraba en la zona posterior de la boca. Conclusión: Una detallada exploración clínica y radiológica del estado pulpar y periapical se debe realizar antes del inicio de un tratamiento de ortodoncia.

Human periapical cyst-mesenchymal stem cells differentiate into neuronal cells.

It was recently reported that human periapical cysts (hPCys), a commonly occurring odontogenic cystic lesion of inflammatory origin, contain mesenchymal stem cells (MSCs) with the capacity for self-renewal and multilineage differentiation. In this study, periapical inflammatory cysts were compared with dental pulp to determine whether this tissue may be an alternative accessible tissue source of MSCs that retain the potential for neurogenic differentiation. Flow cytometry and immunofluorescence analysis indicated that hPCy-MSCs and dental pulp stem cells spontaneously expressed the neuron-specific protein ß-III tubulin and the neural stem-/astrocyte-specific protein glial fibrillary acidic protein (GFAP) in their basal state before differentiation occurs. Furthermore, undifferentiated hPCy-MSCs showed a higher expression of transcripts for neuronal markers (ß-III tubulin, NF-M, MAP2) and neural-related transcription factors (MSX-1, Foxa2, En-1) as compared with dental pulp stem cells. After exposure to neurogenic differentiation conditions (neural media containing epidermal growth factor [EGF], basic fibroblast growth factor [bFGF], and retinoic acid), the hPCy-MSCs showed enhanced expression of ß-III tubulin and GFAP proteins, as well as increased expression of neurofilaments medium, neurofilaments heavy, and neuron-specific enolase at the transcript level. In addition, neurally differentiated hPCy-MSCs showed upregulated expression of the neural transcription factors Pitx3, Foxa2, Nurr1, and the dopamine-related genes tyrosine hydroxylase and dopamine transporter. The present study demonstrated for the first time that hPCy-MSCs have a predisposition toward the neural phenotype that is increased when exposed to neural differentiation cues, based on upregulation of a comprehensive set of proteins and genes that define neuronal cells. In conclusion, these results provide evidence that hPCy-MSCs might be another optimal source of neural/glial cells for cell-based therapies to treat neurologic diseases.

Periapical tissue repair of dog teeth after intracanal administration of capsaicin 0.075% / Reparação tecidual periapical em dentes de cão após administração intracanal de capsaicina 0.075%

O objetivo deste estudo foi realizar uma avaliação descritiva sobre a reparação tecidual da região periapical de dentes de cães. Material e Métodos: Foram utilizados trinta e seis canais radiculares, sendo dezoito preenchidos com capsaicina 0,075% e hidróxido de cálcio (pasta teste) e os outros dezoito canais preenchidos com hidróxido de cálcio (grupo controle). As análises histológicas foram realizadas para classificar a inflamação como ausente, leve, moderada ou grave. As análises também classificaram a presença ou ausência da reparação tecidual nos períodos de 7, 14 e 30 dias. Resultados: O uso de capsaicina 0,075% não alterou a resposta inflamatória e reparação quando comparado ao grupo controle. Conclusão: Nossos dados sugerem que o grupo teste, o qual utilizou capsaicina 0,075% como pasta intracanal, pode ser indicado para reparação tecidual. Além disso, outros experimentos devem ser realizados para avaliar a possível utilização clínica da capsaicina para odontalgias atípicas...

Objective: The aim of this study was make a descriptively evaluate the repair of the periapical region of dog teeth. Material and Methods: Thirty-six root canals were used, eighteen were filled with 0.075% capsaicin and calcium hydroxide (test paste) and the rest eighteen root canals were filled with calcium hydroxide (control group). Histological analyzes were performed to classify inflammation as absent, mild, moderate or severe. The analyses also classified the presence or absence of repair at 7, 14 and 30 days. Results: The use of 0.075% capsaicin did not modify the inflammatory response and repair when compared to control group. Conclusion: Our data suggests that test group with 0.075% capsaicin as intracanal administration could be indicated for tissue repair; furthermore other experiments should be carried out to evaluate possible clinical use of capsaicin for atypical odontalgia...

Prevalence of Treponemaspp. in endodontic retreatment-resistant periapical lesions

This study investigated the presence of the Treponema species in longstanding endodontic retreatment-resistant lesions of teeth with apical periodontitis, the association of this species with clinical/radiographic features, and the association among the different target species. Microbial samples of apical lesions were collected from twenty-five adult patients referred to endodontic surgery after unsuccessful root canal retreatment. Nested-PCR and conventional PCR were used for Treponema detection. Twenty-three periradicular tissue samples showed detectable levels of bacterial DNA. Treponema species were detected in 28% (7/25) of the cases. The most frequently detected species were T. socranskii (6/25), followed by T. maltophilum (3/25), T. amylovorum (3/25), T. lecithinolyticum(3/25), T. denticola (3/25), T. pectinovorum (2/25) and T. medium(2/25). T. vicentii was not detected in any sample. Positive statistical association was found between T. socranskiiand T. denticola,and between T. maltophilumand T. lecithinolyticum. No association was detected between the presence of any target microorganism and the clinical or radiographic features. Treponemaspp.are present, in a low percentage, in longstanding apical lesions from teeth with endodontic retreatment failure.

Agregado de trióxido mineral e uso como material retro-obturador em cirurgia paraendodôntica / Mineral trioxide aggregate and the use as a material for retrofilling endodontic surgery

O Agregado de Trióxido Mineral (MTA) foi desenvolvido com a finalidade de selar perfurações dentárias que ocorrem acidentalmente. A obturação retrógrada consiste no tratamento de lesões perirradiculares que visa solucionar complicações decorrentes do tratamento endodôntico mal sucedido. Materiais como o MTA têm sido propostos com o objetivo de promover o selamento do canal radicular por via retrógrada. O objetivo deste trabalho foi realizar uma revisão de literatura sobre o uso de MTA na Endodontia, abordando aspectos de sua apresentação, composição, propriedades físicas, químicas e biológicas, aplicações clínicas, enfatizando sua utilização na prática cirúrgica-periapical. Concluiu-se que o MTA pode ser empregado no retratamento endodôntico cirúrgico, apresentando-se como material promissor.

The Mineral Trioxide Aggregate (MTA) was initially developed in order to seal dental fractures that may occur accidentally. The retrograde obturation to solve complications by unsuccessful endodontic treatment. Various materials have been proposed, aiming to promote the sealing of the root canal by retrograde via. The objective of this study was to review the literature on the mineral trioxide aggregate in Endodontics, regarding to the presentation, composition, physical, chemical and biological properties, clinical applications It has concluded that MTA can be used on surgical endodontic retreatment.