Root canal treatment of type Ⅱ and ⅢA double dens invaginatus in maxillary lateral incisor: a case report / 华西口腔医学杂志

Dens invaginatus is a rare developmental anomaly of the teeth that is caused by the infolding of enamel organs or the penetration of their proliferations into dental papillae before calcification has occurred. The presence of double dens invaginatus is extremely rare. This paper describes the use of cone beam computed tomography in the evaluation of a maxillary lateral incisor with double dens invaginatus and periapical periodontitis. The tooth was treated through microscopic root canal therapy. The tooth was free of clinical symptoms, and the periradicular lesion narrowed during the follow-up period of 1 year.

Root canal contamination or exposure to lipopolysaccharide differentially modulate prostaglandin E 2 and leukotriene B 4 signaling in apical periodontitis

Abstract Purpose To evaluate the kinetics of apical periodontitis development in vivo , induced either by contamination of the root canals by microorganisms from the oral cavity or by inoculation of bacterial lipopolysaccharide (LPS) and the regulation of major enzymes and receptors involved in the arachidonic acid metabolism. Methodology Apical periodontitis was induced in C57BL6 mice (n=96), by root canal exposure to oral cavity (n=48 teeth) or inoculation of LPS (10 µL of a suspension of 0.1 µg/µL) from E. coli into the root canals (n= 48 teeth). Healthy teeth were used as control (n=48 teeth). After 7, 14, 21 and 28 days the animals were euthanized and tissues removed for histopathological and qRT-PCR analyses. Histological analysis data were analyzed using two-way ANOVA followed by Sidak's test, and qRT-PCR data using two-way ANOVA followed by Tukey's test (α=0.05). Results Contamination by microorganisms led to the development of apical periodontitis, characterized by the recruitment of inflammatory cells and bone tissue resorption, whereas inoculation of LPS induced inflammatory cells recruitment without bone resorption. Both stimuli induced mRNA expression for cyclooxygenase-2 and 5-lipoxygenase enzymes. Expression of prostaglandin E 2 and leukotriene B 4 cell surface receptors were more stimulated by LPS. Regarding nuclear peroxisome proliferator-activated receptors (PPAR), oral contamination induced the synthesis of mRNA for PPARδ, differently from inoculation of LPS, that induced PPARα and PPARγ expression. Conclusions Contamination of the root canals by microorganisms from oral cavity induced the development of apical periodontitis differently than by inoculation with LPS, characterized by less bone loss than the first model. Regardless of the model used, it was found a local increase in the synthesis of mRNA for the enzymes 5-lipoxygenase and cyclooxygenase-2 of the arachidonic acid metabolism, as well as in the surface and nuclear receptors for the lipid mediators prostaglandin E2 and leukotriene B4.

Comparison of apical periodontitis repair in endodontic treatment with calcium hydroxide-dressing and aPDT

Abstract This study evaluated the effect of antimicrobial photodynamic therapy (aPDT) on the endodontic treatment of apical periodontitis (AP). AP was induced in 48 premolars of 6 dogs. After biomechanical preparation, the teeth were divided into 4 groups: Calcium-Hydroxide (CH)/120d and CH/180d: root canals filled with CH-based dressing for 15 days before obturation; aPDT/120d and aPDT/180d: conditioning with phenothiazine photosensitizer (10 mg/mL) for 1 minute and irradiation with diode laser in the same session as obturation. Root filling was performed with AH Plus sealer. After the experimental periods, animals were euthanized and teeth were submitted for histology. HE staining was performed for descriptive analysis of the periapical region, measurement of apical periodontitis and for inflammatory cells, and blood vessels count. Immunohistochemistry was performed for osteopontin (OPN) and alkaline phosphatase (ALP). Data were analyzed statistically by two-way ANOVA and chi-square test (α = 5%). Teeth in Group CH/120d presented only a slightly enlarged periodontal ligament (PL) with advanced repair. Group aPDT/120d presented the PL moderately enlarged, with moderate inflammatory infiltrate and few collagen fibers. The same pattern was observed at 180 days. AP lesions in CH-treated groups were smaller than those in aPDT-treated groups (p < 0.001) with more blood vessels (p < 0.0001), regardless of the evaluation period, without significant differences in the number of inflammatory cells (p > 0.05). CH-treated groups showed significantly more intense immunostaining for ALP and OPN (p < 0.001) in both periods. Although aPDT stimulated angiogenesis and expression of bone formation markers, the two-session endodontic treatment with CH-based dressing promoted better apical periodontitis repair.

Cytokines and chemokines associated with Treg/Th17 response in chronic inflammatory periapical disease

Abstract Cytokines and chemokines have a fundamental role in the maintenance of inflammation and bone response, which culminate in the development of chronic periapical lesions. Regulatory (Treg) and Th17 cytokines play a key role in regulating the immune response involved in this process. The aim of this study was to investigate the role of Treg and Th17 cells in chronic inflammatory periapical disease, by comparing the expression of the immunoregulatory mediators TGF-β, IL-10, CCL4, and the proinflammatory IL-17 and CCL20 in the periapical tissue of teeth with pulp necrosis, with and without associated chronic lesions. Eighty-six periapical tissue samples were obtained from human teeth. The samples were divided into three groups: pulp necrosis with a periapical lesion (n=26); pulp necrosis without a periapical lesion (n=30), and control (n=30). All samples were submitted to histopathological analysis and cytokine and chemokine measurement through ELISA. Statistical analyses were done with Kruskal-Wallis and Mann-Whitney tests and Spearman correlation. The group with pulp necrosis and a periapical lesion showed a higher expression of CCL4 and TGF-β in comparison with pulp necrosis without a lesion. CCL20 was higher in the group with a periapical lesion when compared to the control. In all groups there was a weak positive correlation between IL-17/CCL20, IL-10/CCL4, and IL-17/TGF-β. Both types of cytokines, pro-inflammatory and immunoregulatory, occur simultaneously in periapical tissue. However, a rise in immunosuppressive cytokines and chemokines (CCL4 and TGF-β) in periapical lesions suggests a role of these cytokines in stable periapical disease.

Periodontitis apical: caracterización histológica y morfométrica de quistes radiculares y granulomas periapicales / Apical periodontitis: histological and morphometric characterization of radicular cysts and periapical granulomas

La periodontitis apical es una patología inflamatoria que afecta los tejidos periapicales de un diente desvitalizado. El objetivo de este estudio fue caracterizar histológica y morfométricamente las lesiones de quistes y granulomas utilizando microscopía óptica. Se analizaron seis biopsias obtenidas de dientes con indicación de exodoncia. El análisis histológico se realizó mediante microscopía óptica y microfotografías, con análisis de contraste de imágenes y conteo celular mediante ImageJ. Descripción de las características histológicas: en los quistes se observaron cavidades rodeadas de epitelio escamoso estratificado no queratinizado y una cápsula fibrosa compuesta de fibrocitos, fibroblastos e infiltrado inflamatorio crónico; en los granulomas se observaron capilares, una capsula fibrosa de fibrocitos/fibroblastos y un infiltrado inflamatorio de predominio linfocitario. Cuantificación del número celular de infiltrado inflamatorio: para quistes fue de 9,2 cel/10000 µm2, mientras que para granulomas fue de 20,8 cel/10000 µm2, sin diferencias estadísticas significativas entre ambos (p=0,654). Cuantificación del número celular de fibrocitos/fibroblastos: para quistes fue de 15,4 cel/10000 µm2, mientras que para granulomas fue de 18,5 cel/10000 µm2, sin diferencia estadística significativa (p=0,499). Porcentaje de colágeno tipo I: para los quistes fue de 37,8±19,2 %, mientras que para granulomas fue de 33,8±23,3 %, sin diferencias estadísticas significativas (p=0,704). Se observó una correlación negativa moderada para el infiltrado inflamatorio (R=0,637) y una correlación positiva baja para fibrocitos/fibroblastos (R=0,121), en relación a la cantidad de colágeno tipo I. Medición del área de las lesiones periapicales: el promedio total de las lesiones fue de 10,7±5,0 mm2, siendo el mayor tamaño un quiste de 18,1 mm2 y el menor un granuloma de 5,2 mm2. El análisis histológico permite realizar un diagnóstico diferencial de lesiones con características similares y así definir el tratamiento más adecuado.

Apical periodontitis is an inflammatory pathology that affects the periapical tissues of a devitalized tooth. The aim of this study was to histologically and morphometrically characterize lesions of cysts and granulomas using light microscopy. Six biopsies obtained from teeth with indication of exodontia were analyzed. The histological analysis was carried out by means of optical microscopy and microphotographs, with contrast analysis of images and cell count by ImageJ. A description of the histological characteristics was made, observing the cavities surrounded by stratified squamous non-keratinized epithelium and a fibrous capsule composed of fibrocytes, fibroblasts and chronic inflammatory infiltrate; in the granulomas, capillaries, a fibrous capsule of fibrocytes/fibroblasts and a predominantly lymphocytic inflammatory infiltrate were observed. In relation to quantification of the cellular number of inflammatory infiltrate, for cysts itwas of 9.2 cel / 10000 mm2, while for granulomas it was 20.8 cel / 10000 mm2, without significant statistical differences between both (p = 0.654). The quantification of the fibrocyte / fibroblast cell number was, for cysts, 15.4 cells / 10000 mm2, while for granulomas it was 18.5 cells / 10000 mm2, without significant statistical difference (p = 0.499). With respect to the percentage of collagen type I, for the cysts was 37.8 ± 19.2%, while for granulomas it was 33.8 ± 23.3%, without significant statistical differences (p = 0.704). A moderate negative correlation was observed for the inflammatory infiltrate (R = 0.667) and a low positive correlation for fibrocytes / fibroblasts (R = 0.121), in relation to the amount of type I collagen. Measurement of the area of the periapical lesions: the total average of lesions were 10.7 ± 5.0 mm2, the largest being a cyst of 18.1 mm2 and the smallest a granuloma of 5.2 mm2. The histological analysis allows to make a differential diagnosis of lesions with similar characteristics and thus define the most appropriate treatment.

Influence of genetic polymorphisms in genes of bone remodeling and angiogenesis process in the apical periodontitis

Abstract Persistent apical periodontitis (AP) is a situation involving an inflammatory and immune response caused mainly by anaerobic polymicrobial infection of the root canal system and the outcome and follow-up of the root canal treatment has been reported as intimately related to host response. The apical periodontitis repair might be associated with genetic polymorphisms. This study aimed to evaluate the association between HIF1A genetic polymorphisms (rs2301113 and rs2057482) with PAP in Brazilian patients. Subjects with at least 1 year of follow-up after root canal therapy (RCT) were recalled. Sixty-four subjects with signs/symptoms of PAP and 84 subjects with root canal-treated teeth exhibiting healthy perirradicular tissues (healed) were included. Genomic DNA was extracted from saliva and used for HIF1A genotyping by real-time PCR. Genotype and allele frequencies were compared by c2 or Fisher's exact tests and odds ratio was implemented, using Epi Info 3.5.2. All tests were performed with an established alpha of 0.05. There was no association between allele and genotype distribution for HIF1As polymorphisms and PAP (p>0.05). The genetic polymorphisms in HIF1A were not associated with persistent apical periodontitis.

Resumo A periodontite apical persistente (PAP) é uma condição que envolve uma resposta inflamatória e imunológica causada principalmente por infecções polimicrobianas de origem anaeróbia no sistema de canais radiculares, tornando o resultado e o acompanhamento do tratamento do canal radicular intimamente relacionados à resposta do hospedeiro. O reparo da periodontite apical pode estar associado a polimorfismos genéticos. Este estudo teve como objetivo avaliar a associação entre os polimorfismos genéticos do HIF1A (rs2301113 e rs2057482) com a PAP em pacientes brasileiros. Indivíduos com pelo menos 1 ano de acompanhamento após o tratamento do canal radicular (TCR) foram agendados para consulta de acompanhamento. Sessenta e quatro indivíduos com sinais/sintomas de PAP e 84 indivíduos com dentes tratados endodonticamente e tecidos perirradiculares saudáveis (cicatrizados) foram incluídos no presente estudo. O DNA genômico foi extraído da saliva e utilizado para a genotipagem do HIF1A por PCR em tempo real. O genótipo e as frequências alélicas foram comparados por teste c2 ou exato de Fisher e odds-ratio foi implementado por meio do software Epi Info 3.5.2. Todos os testes realizados foram estabelecidos com a=0,05. Não houve associação entre alelo e distribuição genotípica para polimorfismos do HIF1A e PAP (p> 0,05). Os polimorfismos genéticos em HIF1A não foram associados à periodontite apical persistente.

Omega 3 fatty acids reduce the triglyceride levels in rats with apical periodontitis

Abstract The aim of this study was to evaluate the influence of the prophylactic and therapeutic supplementation with omega 3 polyunsaturated fatty acids (w-3 PUFAs) on the lipid profile and periapical bone resorption in rats with apical periodontitis. Forty male rats were divided into groups: control rats (C), rats treated with w-3 PUFAs (C+O), rats with pulp exposure-induced apical periodontitis (AP), and rats with AP treated with w-3 PUFAs (AP+O). The administration of w-3 PUFAs was carried out orally once a day for 15 days before pulp exposure and, subsequently, for an additional 30 days after pulp exposure. AP was induced by exposing pulpal tissues to the oral environment. The samples were collected after 30 days. Triglycerides and cholesterol levels were enzymatically measured using the Trinder method. The jaws were collected and submitted for histological analysis. Two-way analysis of variance and Kruskal-Wallis tests were used for statistical analysis, and the significance was set at p<0.05. The triglyceride levels of the AP group were significantly higher than those of the C, C+O and AP+O groups (p<0.05). However, the difference in the cholesterol levels among the groups was not significant (p>0.05). Rats with AP showed larger areas of bone resorption as well as higher inflammatory intensity compared with rats with AP supplemented with w-3 PUFAs. It may be concluded that the presence of multiple AP foci increased the triglyceride levels. In addition, omega 3 supplementation might reduce these levels in rats with AP, as well as the bone resorption areas of periapical tissues.

Resumo O objetivo deste estudo foi avaliar a influência da suplementação profilática e terapêutica com os ácidos graxos ômega-3 no perfil lipídico e na reabsorção óssea, em ratos com periodontite apical. Quarenta ratos machos foram divididos em grupos: ratos controle (C), ratos tratados com ácidos graxos ômega-3 (C+O), ratos com periodontite apical induzida por meio de exposição pulpar (PA), ratos com PA tratados com ácidos graxos ômega-3 (PA+O). A administração do ômega-3 foi realizada oralmente, uma vez ao dia durante 15 antes da exposição pulpar e, subsequentemente, por mais 30 dias depois da exposição pulpar. A PA foi induzida por meio da exposição do tecido pulpar ao ambiente oral. Após 30 dias, os ratos foram mortos e os níveis de triglicérides e colesterol foram mensurados pelo método enzimático de Trinder. As mandíbulas foram coletadas e submetidas à análise histológica. Análise de variância de dois fatores e teste de Kruskal-Wallis foram utilizados para análise estatística, e o nível de significância foi de p < 0,05. Os níveis de triglicérides do grupo PA foram significativamente maiores que dos grupos C, C+O e PA+O (p<0,05). Entretanto, não houve diferença significativa nos níveis de colesterol entre os grupos (p>0,05). Ratos com PA apresentaram maior área de reabsorção óssea bem como maior intensidade no infiltrado inflamatório comparados aos ratos com PA suplementados com ômega-3. Pode-se concluir que a presença de múltiplos focos de PA aumentou os níveis de triglicérides. Além disso, a suplementação com ômega-3 pode reduzir estes níveis em ratos com PA, bem como a área de reabsorção óssea dos tecidos periapicais.

MMP2 and MMP9 are Associated with Apical Periodontitis Progression and Might be Modulated by TLR2 and MyD88

Abstract The aim of this study was to evaluate the expression of MMP2 and MMP9 during apical periodontitis (AP) progression in TLR2 (TLR2 KO) and in MyD88 (MyD88 KO) knockout mice compared to wild type (WT) mice. AP was induced in mandibular first molars of TLR2 KO (n= 18), MyD88 KO (n= 18), and WT mice (n= 18). After 7, 21, and 42 days, the animals were euthanized and the jaws were dissected and subjected to histotechnical processing. Subsequent sections were stained by immunohistochemistry and evaluated for detection of MMP2 and MMP9. Statistical analysis of the semi-quantitative analysis of immunohistochemistry was performed using chi-square test (α = 0.05). In the initial periods of AP progression, an increased expression of MMP9 in the TLR2 KO and MyD88 KO mice was observed. In the final periods of AP progression, a reduction of MMP2 expression and an increase of MMP9 expression in the TLR2 KO mice were observed. MMP2 and MMP9 production was modulated for TLR2 and MyD88 during apical periodontitis progression.

Resumo O objetivo deste estudo foi avaliar a expressão de MMP2 e MMP9 durante a progressão da periodontite apical (AP) em camundongos knockout para TLR2 (TLR2 KO) e MyD88 (MyD88 KO) comparados aos camundongos wild type (WT). A AP foi induzida nos primeiros molares inferiores dos camundongos TLR2 KO (n = 18), MyD88 KO (n = 18) e WT (n = 18). Após 7, 21 e 42 dias, os animais foram eutanaziados e as mandíbulas foram dissecadas e submetidas a processamento histotécnico. As lâminas foram coradas por imuno-histoquímica e analisadas para a detecção de MMP2 e MMP9. A análise estatística semi-quantitativa da imuno-histoquímica foi realizada pelo teste qui-quadrado (α = 0,05). Nos períodos iniciais de progressão AP, foi observada uma expressão aumentada de MMP9 nos camundongos TLR2 KO e MyD88 KO. Nos períodos finais de progressão AP, observou-se uma redução da expressão de MMP2 e um aumento da expressão de MMP9 nos camundongos TLR2 KO. A produção de MMP2 e MMP9 foi modulada por TLR2 e MyD88 durante a progressão da periodontite apical.

Dendritic cells and their relation to apical peridontitis

Abstract: The purpose of this manuscript was to re-discuss apical periodontitis, apical biofilm, and its possible relationship with dendritic cells (DC). DCs are potent regulators of the immune system and their function is divided into three categories that involve the presentation of antigens: the presentation of antigens and activation of T cells; a not well established category suggested that DCs induce and maintain immunological tolerance; and the maintenance of the immune memory in conjunction with B cells. DCs in periapical inflammatory lesions are composed of at least two subpopulations that can be distinguished on the basis of ultrastructure and phenotype. These populations might differ in lineage, state of maturation, differentiation, activation, and/or function. The authors hereby analyzed the root apexes of teeth under SEM, after performing apicoectomy due to the failure of conventional endodontic treatment. Microbial biofilm with multispecies and areas of resorption with the presence of Howship lacunae, and images suggestive of denditric cells could be observed. The presence of DCs in periapical lesion could be an indication of the severity of the lesion, with a constant presence of antigen in the periradicular region.

Etiologic role of root canal infection in apical periodontitis and its relationship with clinical symptomatology

Abstract: Evidence shows the polymicrobial etiology of endodontic infections, in which bacteria and their products are the main agents for the development, progression, and dissemination of apical periodontitis. Microbial factors in necrotic root canals (e.g., endotoxin) may spread into apical tissue, evoking and supporting a chronic inflammatory load. Thus, apical periodontitis is the result of the complex interplay between microbial factors and host defense against invasion of periradicular tissues. This review of the literature aims to discuss the complex network between endodontic infectious content and host immune response in apical periodontitis. A better understanding of the relationship of microbial factors with clinical symptomatology is important to establish appropriate therapeutic procedures for a more predictable outcome of endodontic treatment.

Immunohistochemical and mRNA expression of RANK, RANKL, OPG, TLR2 and MyD88 during apical periodontitis progression in mice

Abstract Objective To evaluate and correlate, in the same research, the mRNA expression and the staining of RANK, RANKL, OPG, TLR2 and MyD88 by immunohistochemistry in the apical periodontitis (AP) progression in mice. Material and Methods AP was induced in the lower first molars of thirty-five C57BL/6 mice. They were assigned to four groups according to their euthanasia periods (G0, G7, G21 and G42). The jaws were removed and subjected to histotechnical processing, immunohistochemistry and real-time reverse transcription-PCR (qRT-PCR). Data were analyzed with parametric and nonparametric tests (α=0.05). Results An increase of positive immunoreactivity for RANK, RANKL, OPG, TLR2 and MyD88 was observed over time (p<0.05). The RANKL expression was different between the groups G0 and G42, G21 and G42 (p=0.006), with G42 presenting the higher expression in both comparations. The OPG expression was statistically different between the groups G0 and G7, G7 and G21 and G7 and G42 (p<0.001), with G7 presenting higher expression in all the time points. The TLR2 expression was different between the groups G0 and G42 (p=0.03), with G42 showing the higher expression. The MyD88 expression presented a statistical significant difference between groups G7, G21 and G42 compared with G0 (p=0.01), with G0 presenting the smallest expression in all the comparisons. The Tnfrsf11/Tnfrsf11b (RANKL/OPG) ratio increased with the AP progression (p=0.002). A moderate positive correlation between MyD88 and RANKL (r=0.42; p=0.03) and between MyD88 and TLR2 (r=0.48; p<0.0001) was observed. Conclusion The expression of the RANK, RANKL, OPG, MyD88 and TLR2 proteins as well as the ratio Tnfrsf11/Tnfrsf11b (RANKL/OPG) increased with AP progression. There was also a moderate positive correlation between the expression Myd88-Tnfrsf11 and Tlr2-Myd88, suggesting the relevance of Tlr2-Myd88 in bone loss due to bacterial infection.

Current trends of genetics in apical periodontitis research

Abstract: Genetics is an emerging topic in endodontic research focusing on the host response regarding the pathogenesis of apical periodontitis (AP). A number of genetic epidemiological studies carried out by many investigators worldwide have shown evidence of an association between certain candidate genes and AP. Some studies have been conducted on knockout mice with a deficiency in certain proteins, leading to more or less severe AP, and thus suggesting a pivotal role of these genes in AP pathogenesis. Other research has evaluated the association between genetic polymorphisms in humans with different AP aspects; these studies pointed out that genetic polymorphisms in some candidate genes are involved in inter-individual variations in their response to AP. Therefore, the objective of this report was to provide an updated overview of the genes involved in AP pathogenesis, with a focus on the most relevant candidate genes.

Apical Negative Pressure irrigation presents tissue compatibility in immature teeth

Abstract Aim: To compare the apical negative pressure irrigation (ANP) with conventional irrigation in the teeth of immature dogs with apical periodontitis. Methods: Fifty-two immature pre-molar root canals were randomly assigned into 4 groups: ANP (n=15); conventional irrigation (n=17); healthy teeth (control) (n = 10); and teeth with untreated apical periodontitis (control) (n=10). After induction of apical periodontitis, teeth were instrumented using EndoVac® (apical negative pressure irrigation) or conventional irrigation. The animals were euthanized after 90 days. The sections were stained by HE and analyzed under conventional and fluorescence microscopy. TRAP histoenzymology was also performed. Statistical analyses were performed with the significance level set at 5%. Results: There was difference in the histopathological parameters between ANP and conventional groups (p<0.05). The ANP group showed a predominance of low magnitude inflammatory infiltrate, a smaller periodontal ligament, and lower mineralized tissue resorption. There were no differences in the periapical lesion extensions between the ANP and conventional groups (p>0.05). However, a lower number of osteoclasts was observed in the ANP group (p<0.05). Conclusion: The EndoVac® irrigation system presented better biological results and more advanced repair process in immature teeth with apical periodontitis than the conventional irrigation system, confirming the hypothesis.

Evaluación de Lesiones Periapicales en Pacientes Derivados a Cirugía Periapical Mediante Tomografía Computarizada de Haz Cónico / Evaluation of Periapical Lesions by Cone Beam Computed Tomography in Patients Referred for Apical Surgery

El uso de la tomografía computarizada de haz cónico (CBCT) en endodoncia ha ido en aumento, justificando su uso en casos más complejos, como cirugías periapicales. El objetivo fue evaluar las características imagenológicas encontradas en un grupo de pacientes derivados a cirugía periapical, mediante el uso de CBCT. Se realizó un estudio observacional descriptivo, en un grupo de pacientes, derivados a cirugía periapical, a los cuales se realizó un examen de CBCT, evaluación clínica y radiografía periapical. Un total de 18 pacientes fueron examinados (6 hombres y 12 mujeres), cuyas edades estaban entre los 19 y 64 años de edad. El diámetro mayor de las lesiones varió entre 6 mm a 16 mm. El uso de CBCT en cirugías periapicales entrega información más completa al cirujano, ya que permite mayor precisión al realizar el acceso quirúrgico y detecta un mayor número de lesiones periapicales que con la radiografía periapical, logrando en casos complejos un mejor diagnóstico y planificación del tratamiento.

The use of cone beam computed tomography (CBCT) in endodontics has increased, justifying its use in more complex cases, such as apical surgery. The aim was to evaluate the radiologic characteristics found in a group of patients referred to apical surgery, using CBCT. A descriptive study was conducted in a group of patients referred for apical surgery. In these patients, a clinical examination, a conventional radiographic evaluation and CBCT were performed. A total of 18 patients were examined (6 men and 12 women), ages were between 19 and 64 years old. The major diameter of the lesions ranged from 6 mm to 16 mm. The use of CBCT in apical surgery provides more complete information to the surgeon, allowing greater precision when performing surgical access and detects a greater number of periapical lesions than with conventional radiography. In complex cases is possible obtain better diagnosis and treatment planning.

Treg and Th17 cells in inflammatory periapical disease: a systematic review

Abstract: The process involved in periapical lesions, which occur as an outcome of pulpal necrosis, is regulated by the immune system including regulatory T cells (Treg) and T helper 17 cell (Th17) responses. The objective of this study was to conduct a frequency systematic review to determine the presence of Treg/Th17 responses and the influence of these cells in the progression of chronic inflammatory periapical lesions in humans. A systematic computerized search was carried out in Pubmed, Medline, Web of Science and Scopus electronic databases from their date of inception through the first week of May 2017. In addition, the reference lists of the included articles and the grey literature were hand-searched. Articles that evaluated the presence and influence of Treg/Th17 in the progression of human periapical lesions were included. Study selection and the quality assessment of the included articles (using the Newcastle-Ottawa scale) were carried out by two authors. Fifty-seven titles/abstracts were screened and eight studies met the eligibility criteria and were included in this systematic review. The included studies showed large variation in the type of periapical lesion assessed, mean age, age range, type of experiment and findings regarding the participation of Th17 and Treg in the status of inflammatory periapical lesions. The studies showed the involvement of Treg in the modulation of the inflammatory response in radicular cysts and periapical granulomas. This systematic review highlights the relationship between Treg and Th17 acting in a subtle balance inhibiting or promoting the progression of human periapical lesions.

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.

Aspectos atuais do tratamento da infeccão endodôntica / Current aspects of root canal system infection's therapy

A Endodontia é uma ciência que engloba a etiologia, diagnóstico, prevenção e tratamento da periodontite apical e suas repercussões no organismo. Recu rsos tecnológ icos no diagnóstico, exploração e novas estratégias associadas principalmente à limpeza e desinfecção do sistema de canais radiculares, modelagem e obturação do espaço endodôntico, de acordo com bases biológicas,permitirão a obtenção de melhores padrões de sucesso pós-tratamento.

Endodontics is a science that embodies etiology, diagnosis, prevention, and treatment of apical periodontitis and its repercussion in the organismo Technological resources in diagnosis and root canal negotiation, and new strategies , associated to mainly cleaning and eliminating the infection of the root canal system, shaping, and filling the endodontic space, according to biological bases, will allow us to reach higher standards of post-treatment success.

Tratamento endodôntico de incisivo lateral superior após falha da cirurgia parendodôntica / Endodontic treatment of maxillary lateral incisor after failed surgery paraendodontic

O propósito deste artigo é relatar um caso clínico no qual foi realizada uma intervenção cirúrgica parendodôntica no incisivo lateral superior esquerdo em um paciente para remoção de uma lesão no periodonto apical, sem um prévio tratamento endodôntico, tendo a incisão, a enucleação da lesão e a sutura sido feitas de maneira equivocada, provocando uma fenestração tecidual no tecido gengival, expondo o tecido ósseo ao meio bucal, com consequente infecção e grande quantidade de exsudato purulento. Foi realizado um tratamento endodôntico no dente em questão, utilizando-se a limpeza e modelagem do canal com instrumentação rotatória e hipoclorito de sódio a 5,25%, cavitação ultrassônica com EDTA a 17%, curativo intracanal com hidróxido de cálcio e, em uma sessão posterior,obturação com guta-percha termoplastificada e cimento resinoso. Durante o exame clínico radiográfico de proservação realizado após quatro meses de concluído o tratamento endodôntico, foi observado a recuperação do tecido gengival e a radiografia periapical mostrou uma regeneração do tecido ósseo, onde antes existia a lesão.

The intention of this article is to tell a clinical case in which was made a endodontic surgery in a patient to remove a lesion in the apical periodonto and was carried throughan endodontic surgical intervention in the maxillary lateral incisor without a previous endodontic treatment, having the incision, the enucleation of the injury and the been suture made in a mistake way, provoking a tecidual fenestration in the gum of the patient,displaying the osseous tissue to the buccal way, with consequent infection and greatamount of purulent exudates. An endodontic treatment in the tooth in question was carried through, using itself cleaning and shaping of the canal with rotatory instrumentation and 5,25% sodium hypochlorite, ultrasonic cavitation with 17% EDTA, dressing intra canalwith of calcium hydroxide and, in a posterior session, obturation with termoplastificad gutta-percha and resinous sealer. During the clinical examination of flare-up conducted after four months of carried through the endodontic treatment was observed a recovery of the gum tissue and the periapical x-ray showed a regeneration of the osseous tissue,where before the injury existed.

Envolvimento de sinais coestimulatórios na periodontite apical crônica em humanos / Co-stimulatory signals in chronic periapical periodontitis

As lesões periapicais são induzidas por uma infecção crônica da polpa dental. Antígenos microbianos estimulam a resposta imune específica e inespecífica nos tecidos apicais. Como consequência desse processo, diante da incapacidade das defesas do hospedeiro para erradicar a infecção, uma lesão periapical é formada, com o objetivo de restringir a invasão microbiana. O desenvolvimento da periodontite apical crônica depende de uma fina regulação da ativação dos linfócitos. A ativação das células T requer dois sinais, um mediado pelo complexo TCR, após o reconhecimento do antígeno, e o outro mediado pela interação dos receptores coestimulatórios. CD28 é um receptor coestimulatório, enquanto CTLA-4 e PD-1 induzem um sinal inibitório para a ativação de células T. Para compreender o envolvimento de células T na periodontite apical crônica, avaliamos a presença destas células na lesão periapical e os fatores coestimulatórios, citocinas e espécies reativas do oxigênio que estas células estariam produzindo. As amostras analisadas foram de tecido gengival para o grupo controle (n = 20) e lesões periapicais para o grupo com periodontite apical crônica (n = 20). Quanto ao perfil celular das lesões periapicais, os resultados mostraram que linfócitos T (59,3 ± 3,7%) foram as células predominantes, sendo a subpopulação CD4+ (72,7 ± 3,4%) a mais encontrada. A seguir, verificou-se a expressão de moléculas de superfície em células T. Observou-se que a expressão de CD28 (0,5 ± 0,5%) foi significativamente mais baixa em amostras de lesões periapicais que no grupo controle principalmente para linfócito T CD8+. Já CTLA-4 foi identificado em altos níveis para pacientes com periodontite apical tanto para CD3+CD4+ (86,1 ± 2,6%) quanto para CD3+CD8+ (59,8 ± 8,6%). PD-1 (73,5 ± 5,6%) e PD-L1 (59,8 ± 8,6%) apresentaram alta positividade para CD3+CD4+. Esses resultados indicaram um possível envolvimento da via de sinalização de PD-1 e PD-L1 na modulação da resposta de células T de...

Periapical lesions are induced by the chronic infection of dental pulp. Microbial antigens stimulate both non-specific and specific immune response in periapical tissue. As a consequence of these processes and the inability of host defense mechanisms to eradicate infection, chronic periapical lesion are formed, with the aim of restricting microbial invasion. Negative co-stimulatory signals mediated via cell surface molecules such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death-1 (PD-1) play a critical role in down- modulation immune responses and maintaining peripheral tolerance. Both CTLA-4 and PD-1 are induced on actived T cell, and these are involved in the immunophatogenesis of periapical lesions. Inhibitory signals mediated via molecules such as programmed-death-1 (PD-1) play a critical role in down-modulating immune responses and maintaining peripheral tolerance. We investigated the involvement of cytokines and PD-1 engagement in mediating the T cell activation in chronic periapical diseases. Gingival samples from healthy individuals (n= 20) and patients with chronic periapical periodontitis (n= 20) were collected and used for the subsequent assays. The leukocytes in the lesion site were evaluated using flow cytometry. The production of cytokines interferon-gamma (IFN-), interleukin (IL)-10, tumor necrosis factor-alpha (TNF-) and transforming growth factor-beta (TGF-) was evaluated by ELISA. We observed a significant increase in the total number of leukocytes from periapical lesions as compared with healthy group. Our results for the composition of infiltrating cell in periapical lesion showed that the predominant cells were lymphocytes T (59,3 ± 3,7%) and contained a higher proportion of CD4+ cells (72,7 ± 3,4%). T cells from patients with periapical lesions expressed significantly higher levels of PD-1 (73,5 ± 5,6%) and PD-L1 (59,8 ± 8,6%). The levels of CTLA-4 were higher in CD3+CD4+ (86,1± 2,6%) and CD3+...

Periodontitis apical y microbiología asociada retratamiento endodóntico / Apical periodontitis and endodontic retreatment associated microbiology

Las bacterias que invaden el espacio pulpar son uno de los principales irritantes causando inflamación de este tejido, que al persistir puede resultar en necrosis. Dicha destrucción tisular permite que las bacterias, sus productos y otros irritantes alojados en el tejido necrótico se difunda desde el conducto hacia el periápice produciendo una lesión inflamatoria en dicha región, por tanto, las especies bacterianas son esenciales en la progresión de las lesiones pulpares y periapicales. Por ello consideramos importante realizar un estudio sobre el tema buscando mejorar la práctica diaria de la especialidad.