Influence of photobiomodulation therapy on root development of rat molars with open apex and pulp necrosis

Abstract This study aimed to evaluate the role of photobiomodulation (PBM) in apexification and apexogenesis of necrotic rat molars with an open apex. Rat molars were exposed to the oral environment for 3 weeks. Canals were rinsed with 2.5% NaOCl and 17% EDTA, filled with antibiotic paste and sealed. After 7 days, canals were rinsed and divided into six groups (n=6): mineral trioxide aggregate (MTA); blood clot (BC); human dental pulp stem cells (hDPSC); MTA+PBM; BC+PBM; and hDPSC+PBM. In hDPSC groups, a 1% agarose gel scaffold was used. Two groups were not exposed: healthy tooth+PBM (n = 6), healthy tooth (n = 3); and one was exposed throughout the experiment: necrotic tooth (n = 3). In PBM groups, irradiation was performed with aluminum gallium indium phosphide (InGaAlP) diode laser for 30 days within 24-h intervals. After that, the specimens were processed for histological and immunohistochemical analyses. Necrotic tooth showed greater neutrophil infiltrate (p < 0.05). Necrotic tooth, healthy tooth, and healthy tooth+PBM groups showed absence of a thin layer of fibrous condensation in the periapical area. All the other groups stimulated the formation of a thicker layer of fibers (p < 0.05). All groups formed more mineralized tissue than necrotic tooth (p < 0.05). PBM associated with MTA, BC, or hDPSC formed more mineralized tissue (p < 0.05). MTA+PBM induced apexification (p < 0.05). Rabbit polyclonal anti-bone sialoprotein (BSP) antibody confirmed the histological findings of mineralized tissue formation, and hDPSC groups exhibited higher percentage of BSP-positive cells. It can be concluded that PBM improved apexification and favored apexogenesis in necrotic rat molars with an open apex.

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.

Inflammatory effect of green propolis on dental pulp in rats

Pulpotomy in deciduous teeth is a controversial issue, especially with regard to alternative materials used for the direct pulp capping of the root canal pulp tissue. The aim of the present study was to perform a histological analysis of the initial reaction of the root canal pulp tissue in rats, following pulpotomy and pulp capping with (1) green propolis extract, (2) iodoform paste, (3) green propolis extract + iodoform and (4) calcium hydroxide paste with saline solution. Analyses were performed after 24 hours, 72 hours and 7 days. The substances containing green propolis extract and iodoform led to the production of an intense inflammatory infiltrate and necrosis in the root canal pulp tissue throughout the analyses. In the calcium hydroxide group, inflammatory infiltrate only prevailed at the 72-hour evaluation. Among the substances tested, calcium hydroxide paste induced the lowest intensity of inflammatory response in the root canal pulp tissue. Longer studies should be carried out to analyze the pulp repair process following pulpotomy and pulp capping with the compounds analyzed.

Orthodontic movement of endodontically treated teeth

Often there is the need of moving teeth endodontically treated or teeth still in endodontic treatment. In order to collaborate with the comprehension and substantiation of the following subjects will be discussed: 1) Orthodontic movement in endodontically treated teeth without periapical lesion, 2) Orthodontic movement in endodontically treated teeth with inflammatory periapical lesion, and 3) Orthodontic movement in teeth endodontically treated due to aseptic pulp necrosis by dental trauma. In practically all situations, endodontically treated teeth to be orthodontically moved must be subjected to a careful evaluation by the endodontist about the conditions, adequate or not, of the endodontic treatment. Then, in this paper it was sought to induce an insight for new clinical researches about the theme that may definitely prove the information obtained by interrelations of information in parallel to clinical practice.

Com frequência, há a necessidade de movimentar-se dentes endodonticamente tratados ou ainda em tratamento endodôntico. Para colaborar com a compreensão e fundamentação do assunto, abordaremos: 1) a movimentação ortodôntica em dentes endodonticamente tratados sem lesão periapical; 2) a movimentação ortodôntica em dentes endodonticamente tratados com lesão periapical inflamatória; e 3) a movimentação ortodôntica em dentes endodonticamente tratados de necrose pulpar asséptica por traumatismo dentário. Em praticamente todas as situações, dentes endodonticamente tratados a serem movimentados ortodonticamente devem ser submetidos a uma avaliação criteriosa, por parte do endodontista, sobre as condições adequadas ou não do tratamento endodôntico. Em seguida, no presente trabalho procurou-se, singelamente, induzir um insight para novas pesquisas clínicas sobre o tema, que possam definitivamente comprovar os conhecimentos obtidos pela inter-relação de conhecimentos em paralelo à prática clínica.

Influence of pulp condition on the accuracy of an electronic foramen locator in posterior teeth: an in vivo study

The aim of this study was to assess, in vivo, the accuracy of the NovApex® electronic foramen locator in determining working length (WL) in vital and necrotic posterior teeth. The NovApex®was used in 144 canals: 35 teeth with vital pulps (68 canals) and 42 teeth with necrotic pulps (76 canals). WL was measured with the NovApex® locator and confirmed using the radiographic method. Differences between electronic and radiographic measurements ranging between 0.0 and 0.4 millimeters were classified as acceptable; differences equal to or greater than 0.5 millimeter were considered unacceptable. Pearson's chi-square test was used to assess the influence of pulp condition on the accuracy of NovApex®(a = 0.05). Regardless of pulp condition, differences between electronic and radiographic WL measurements were acceptable in 73.61% of the canals. No statistically significant differences in accuracy were observed when comparing vital and necrotic canals (p > 0.05). There were 38 unacceptable measurements. In none of these cases was the file tip located beyond the radiographic apex; in 32, it was located short of the NovApex® measurement. Pulp condition had no significant effect on the accuracy of NovApex®.

Tratamento endodôntico em sessão única em dente com necrose pulpar lesão periapical. Relato de caso / Endodontic treatment in one session in teeth with necrotic pulp and periapical lesion. Case report

O preparo biomecânico é a fase endodôntica que tem como finalidade realizar a neutralização do conteúdo séptico e modelagem do canal radicular. É sabido que quando o dente apresenta necrose pulpar, há a presença de bactérias no interior do sistema de canais radiculares e que esse preparo não consegue eliminar por completo as bactérias que se alojam nos túbulos dentinários ou mesmo nos istmos onde os instrumentos não têm ação. Por conta disso, há a necessidade do uso da medicação intra canal na tentativa de neutralizar os restos bacterianos que resistiram ao preparo biomecânico. Este conceito é o mais consagrado entre os profissionais. Ocorre que há também outra linha de pesquisa na qual se admite que mesmo na presença de bactérias, por si só o preparo biomecânico é suficiente para neutralizar o conteúdo séptico do canal principal e, após uma obturação tridimensional, as bactérias que sobreviveram a esta etapa, ficariam confinadas e a reparação da lesão ocorreria naturalmente. O presente trabalho visa demonstrar através de um caso clínico do primeiro molar inferior portador de quatro canais distintos apresentando necrose pulpar e extensa lesão periapical, que o tratamento endodôntico em sessão única pode ser realizado com sucesso

Mechanical preparation is the phase endodontic that aims to clean, neutralize of content septic and shaping the root canal. It is known that when the tooth pulp necrosis present, there is the presence of bacteria inside the root canal system and that this preparation can not completely eliminate the bacteria that lodge in tubules or in the isthmus where the instruments have no action. Because of this, there is the need for intra canal medication use in an attempt to neutralize the remnants of bacteria that resisted the biomechanical preparation. This concept is the most widely used by professionals. It happens that there is a line of research acknowledges that even in the presence of bacteria alone, the biomechanical preparation is sufficient to counteract the main channel and, after a threedimensional obturation, bacteria that have survived to this stage would be confined and repair the injury occur naturally. This paper demonstrates through a case of first molar carrier featuring four distinct channels with pulp necrosis with extensive periapical lesion, the endodontic treatment in one session can be performed successfully

Radiological and histopathological evaluation of experimentally-induced periapical lesion in rats

OBJECTIVE: This study evaluated experimentally-induced periapical bone loss sites using digital radiographic and histopathologic parameters. MATERIAL AND METHODS: Twenty-seven Wistar rats were submitted to coronal opening of their mandibular right first molars. They were radiographed at 2, 15 and 30 days after the operative procedure by two digital radiographic storage phosphor plates (Digora®). The images were analyzed by creating a region of interest at the periapical region of each tooth (ImageJ) and registering the corresponding pixel values. After the sacrifice, the specimens were submitted to microscopic analysis in order to confirm the pulpal and periapical status of the tooth. RESULTS: There was significant statistically difference between the control and test sides in all the experimental periods regarding the pixel values (two-way ANOVA; p<0.05). CONCLUSIONS: The microscopic analysis proved that a periapical disease development occurred during the experimental periods with an evolution from pulpal necrosis to periapical bone resorption.

Microbiological and microscopic analysis of the pulp of non-vital traumatized teeth with intact crowns

OBJECTIVE: This study evaluated the presence of microorganisms and analyzed microscopically the pulp of 20 traumatized human teeth with intact crowns and clinical diagnosis of pulp necrosis, based on the association of at least three of the clinical criteria: crown discoloration, negative response to thermal and electric pulp vitality tests, positive response to vertical and horizontal percussion, pain on palpation or mobility. MATERIAL AND METHODS: Microbiological collection was performed from the root canals to evaluate the presence of microorganisms. The pulp samples were stained with hematoxylin and eosin (H.E.) for histological evaluation of possible morphological alterations. RESULTS: Analysis of results was performed by statistical tests (linear regression test and diagnostic analysis) and subjective analysis of the sections stained with H.E. and revealed that only 15 percent of the sample did not exhibit microbial development. The time elapsed between dental trauma and onset of endodontic intervention ranged from 15 days to 31 months; the percussion test presented high sensitivity (80 percent) for detection of microorganisms in the root canal of traumatized teeth; 3 teeth (15 percent) did not present pulp tissue, being characterized as complete autolysis; analysis of pulp samples was performed on the other 17 cases, among which 3 (15 percent) exhibited partial necrosis without possibility of repair and 14 presented complete necrosis; none of the clinical criteria employed for the diagnosis of pulp necrosis in traumatized teeth was pathognomonic. CONCLUSIONS: The present results allowed the following conclusions: with regard to microbiological findings, 85 percent of teeth presented microorganisms in the root canal, despite the presence of an intact crown. Concerning the microscopic findings, 100 percent of traumatized teeth presented pulp necrosis; the pulp vitality tests based on pulp response to heat, cold and vertical percussion ...

Endoperiodontal lesion due to communication internal root resorption / Lesão endoperiodontal decorrente de reabsorção radicular interna comunicante

Internal root resorptions are usually non-symptomatic and are discovered occasionally throughperiapical radiographs, revealing a very defined and regular outline. These resorptions are progressive,and eventually perforate the periodontium. The present work describes the treatment of a clinicalcase of internal root resorption with periodontal communication, outlining the interrelation betweenperiodontal surgery and endodontic therapy.

As reabsorções internas são normalmente assintomáticas e descobertas ocasionalmente atravésde radiografias periapicais, onde revelam um contorno bem definido e regular. Estasreabsorções são progressivas e eventualmente perfuram o periodonto. O presente trabalhodescreve o tratamento de um caso clínico de reabsorção radicular interna com comunicaçãoperiodontal onde se fizeram necessárias a inter-relação entre a cirurgia periodontal e a terapiaendodôntica convencional.

Histologic evaluation of pulpotomy performed with ethyl-cyanoacrylate and calcium hydroxide / Avaliação histológica de pulpotomia realizada com etil-cianoacrilato e com hidróxido de cálcio

The aim of this study was to evaluate histological aspects of the pulp-dentin complex of dogs submitted to pulpotomy and capped with ethyl-cyanoacrylate and calcium hydroxide. Thirty dog teeth were divided into 2 groups of 15 as follows: Group 1 - ethyl-cyanoacrylate; Group 2 - calcium hydroxide. The pulpotomies were carried out following all of the treatment precautions recommended for dogs. After 30 days the specimens were submitted to histological preparation and were then blindly evaluated by a histologist. Data were analyzed statistically by the Fisher exact test, comparing the two groups. After 30 days, the presence of a hard tissue barrier was observed in 83.3 percent of Group 1, and in 100 percent of Group 2 (p = 0.478). A continuous hard tissue barrier was observed in 50 percent of the ethyl-cyanoacrylate group and 75 percent of the calcium hydroxide group (p = 0.652). It can be concluded that both materials induced hard tissue barrier formation, but Group 2 had a higher percentage than Group 1, with no significant statistical differences; the differences observed between the different barriers (continuous/non-continuous) were not significant between groups and there was no pulpal necrosis in either group.

O objetivo do presente estudo foi avaliar o aspecto histológico do complexo dentino-pulpar de cachorros quando capeado após a pulpotomia com etil-cianoacrilato e hidróxido de cálcio. Trinta dentes de cães foram divididos em 2 grupos de 15 da seguinte forma: Grupo 1 - Etil-cianoacrilato; Grupo 2 - Hidróxido de cálcio. A pesquisa foi realizada tomando-se todos os cuidados recomendados para o tratamento com os cães. Após 30 dias do procedimento realizado os espécimes foram submetidos ao preparo histológico e logo após foram avaliados de forma cega por um histologista. Os resultados foram analisados estatisticamente através do Teste Exato de Fisher. No grupo 1, 83,3 por cento e no grupo 2, 100 por cento dos dentes apresentaram a barreira de tecido duro (p = 0,478). A barreira de tecido duro contínua foi observada em 50 por cento dos casos tratados com etil-cianoacrilato e em 75 por cento dos com hidróxido de cálcio (p = 0,652). Pode-se concluir que tanto o grupo 1 como o grupo 2 induziram a formação da barreira de tecido duro, porém o grupo 2 teve um percentual maior do que o grupo 1, não havendo diferença estatisticamente significante; a diferença observada entre as estruturas das barreiras (contínuas e não-contínuas) não foi significante. A necrose pulpar não foi observada em nenhum grupo.

Ex vivo analysis of the debris remaining in flattened root canals of vital and nonvital teeth after biomechanical preparation with Ni-Ti rotary instruments

The purpose of this study was to assess the presence of apical debris remaining in the apical third of flattened root canals of vital and nonvital teeth after biomechanical preparation with Ni-Ti rotary instruments. Fresh-extracted human mandibular incisors were used in this study. The teeth had clinical indication for extraction and were submitted to cold pulp vitality testing and radiographic examination. Eighteen teeth were selected and randomly assigned to two groups (n=9), according to the clinical diagnosis, i.e., pulp vitality or pulp necrosis. The canals were instrumented with the ProTaper NiTi rotary system in the following sequence: S1 - up to the middle third; SX - at the cervical third; S2- up to the apical third; and S1, F1, F2, F3 - at the working length. The canals were irrigated with 1 percent sodium hypochlorite, dried and were submitted to the histological processing. Sections from the apical third were analyzed by an optical microscope (X40) that was coupled to a computer where the images were captured and analyzed using specific softwares. A grid was placed over these images to assess the total canal area and the areas with debris. Mann-Whitney U-test showed no statistically significant difference (p>0.05) between the teeth with pulp vitality (6.49 ± 3.39) and those with pulp necrosis (5.95 ± 2.22). It may be concluded that the clinical condition of pulp tissue did not interfere with the amount of debris remaining in the apical third of flattened root canals prepared with Ni-Ti rotary instruments.

O objetivo deste estudo foi avaliar a presença de debris no terço apical de canais radiculares achatados de dentes com polpa vital ou não-vital após preparo biomecânico com instrumentos rotatórios de níquel-titânio. Incisivos humanos inferiores recentemente extraídos for usados neste estudo. Os dentes tinham indicação para exodontia e o diagnóstico clínico do estado pulpar foi realizado mediante teste de vitalidade com frio e exame radiográfico. Dezoito incisivos inferiores humanos foram selecionados e distribuídos em dois grupos (n=9), de acordo com o diagnóstico clínico: dentes com a polpa viva ou dentes com a polpa necrosada. Os canais radiculares foram instrumentados com o sistema rotatório ProTaper com instrumentos de NiTi na seguinte seqüência: S1- até o terço médio; SX - no terço cervical; S2 - até no terço apical; e S1, F1, F2, F3 - no comprimento de trabalho. Os canais foram irrigados com hipoclorito de sódio a 1 por cento, secos e submetidos ao processamento histológico. Cortes do terço apical foram analisados em microscópio ótico (40X) acoplado a um computador onde as imagens resultantes foram capturadas e analisadas utilizando programas específicos. Uma grade foi colocada sobre estas imagens para avaliar a área total do canal e as áreas com debris. O teste de Mann-Whitney mostrou não haver diferença estatisticamente significante (p>0,05) entre os dentes com vitalidade pulpar (6,49 ± 3,39) e aqueles com necrose pulpar (5,95 ± 2,22). Concluiu-se que o estado clínico pulpar não interferiu na quantidade de debris remanescentes no terço apical de canais radiculares achatados preparados com instrumentos rotatórios de NiTi.

Displasia cementária periapical: relato de caso / Periapical cemental dysplasia: case report

The authors present a case of periapical cemental dysplasia affecting the mandibular left canine, with vital pulp, in a 43-year-old black female patient, an occurrence that follows the classical cases found in the literature. The need of a careful history, clinical and radiographic exams and vitality tests are emphasized in order to reach the correct diagnosis of this disease

Distribuiçäo de bactérias planctônicas, colônias bacterianas e biofilmes microbianos em dentes decíduos com pulpite e ou necrose pulpar / Distribution of bacterial plankton, bacterial colonies and microbial biofilm on deciduous teeth with pulpitis and pulp necrosis

As bactérias constituem fatores primordiais da contaminaçäo da polpa dentária de dentes decíduos resultando em implicaçöes clínicas e terapêuticas. Com a finalidade de analisar a presença de bactérias planctônicas, colônias e biofilmes microbianos nas estruturas de dentes decíduos portadores de pulpite e necrose pulpar, utilizaram-se 32 dentes decíduos com cárie profunda. Dezesseis dentes foram seccionados no sentido longitudinal e o restante no sentido transversal. Os espécimes foram corados pela hematoxilina-eosina de Harris e Brown e Brenn para análise pela microscopia óptica. A partir da metodologia empregada pôde-se verificar que: 1) Em dentes decíduos com pulpite decorrente de cárie dentária, as bactérias podem ser encontradas nos túbulos dentinários e especialmente no interior do tecido pulpar na área inflamada. Colônias bacterianas e biofilmes microbianos säo visualisados na superfície cariosa e nos focos de liquefaçäo dentinária; 2) As bactérias plactônicas, colônias bacterianas e biofilmes microbianos estäo abundantemente presentes nas câmaras pulpares e canais radiculares de dentes decíduos com necrose pulpar, localizando-se nas superfícies do teto, do soalho da câmara pulpar, nas paredes laterais do canal radicular e, por extensäo, nas paredes externas apicais...

Urgência em Endodontia II / Endodontics urgencies II

Os autores apresentam um revisão de literatura das urgências endodônticas em dentes com polpa mortificada, classificando-as em mortificação pulpar, pericementite apical aguda e abscesso apical agudo. Nesta revisão são abordados, principalmente, etiologia, aspectos clínicos, diagnóstico e tratamento

Tratamento endodôntico de dentes decíduos com necrose pulpar / Pulpectomy in primary teeth: a clinical investigation

Os autores estudaram o comportamento de 23 dentes decíduos necrosados, tratados endodonticamente em uma única sessäo, utilizando a pasta obturadora iodoformada segundo fórmula de Guedes-Pinto & colab. Os dentes näo fistulados responderam ao tratamento com 100 por cento de sucesso clínico, enquanto os fistulados, com 63,64 por cento