Avances en endodoncia regenerativa: reporte de caso con uso de la membrana amniótica humana / Advances in regenerative endodontics: report of a case using a human amniotic membrane

Los procedimientos endodónticos regenerativos (REPs) representan una evolución significativa en el campo de la endodoncia, buscando no sólo tratar la infección o lesión presente en el diente, sino tam-bién promover la regeneración de los tejidos denta-rios afectados. El presente caso clínico muestra un incisivo lateral superior izquierdo con apexogénesis incompleta y diagnóstico de absceso alveolar crónico reagudizado en una paciente de 22 años, en el que se aplicó un procedimiento de endodoncia regenerativa (REPs). La estrategia terapéutica elegida se basó en los principios de ingeniería tisular, incorporando la novedosa aplicación de la membrana amniótica hu-mana liofilizada esterilizada como andamio bioactivo intraconducto. Las evaluaciones clínicas, radiográ-ficas y tomográficas a corto, mediano y largo plazo revelaron el éxito de la terapia. La resolución exitosa mostró en los controles a la pieza dentaria asintomá-tica, con una notable remisión de la patología apical, aumento de la longitud radicular y disminución del calibre apical. Se ha podido destacar la eficacia de los REPs, con una exitosa aplicabilidad de la membra-na amniótica como andamio innovador (AU)

Regenerative endodontic procedures (REPs) represent a significant evolution in the field of endodontics, aiming not only to address the infection or injury within the tooth, but also to promote the regeneration of the affected dental tissues. In this clinical case, an upper left lateral incisor with incomplete apexogenesis and diagnosis of acute exacerbation of a chronic periapical lesion in a 22-year-old patient is presented. A regenerative endodontic procedure (REPs) was applied. The chosen therapeutic strategy was based on tissue engineering principles, incorporating the innovative use of sterilized lyophilized human amniotic membrane as an intraconduct bioactive scaffold. Clinical, radiographic, and tomographic assessments at short, medium, and long-term follow-up revealed the success of the therapy. Successful resolution demonstrated an asymptomatic tooth in the follow-up, with a notable resolution of apical pathology, increased root length, and decreased apical caliber. The effectiveness of REPs has been highlighted, demonstrating the successful applicability of amniotic membrane as an innovative scaffold (AU)

Can a dentin bonding agent prevent color change in regenerative endodontic procedures? An in vitro evaluation

Abstract This in vitro study aimed to determine the efficacy of dentin bonding agents in preventing color changes following Regenerative Endodontic Procedures. One hundred twenty bovine incisors were endodontically prepared and randomly assigned to a two main factors design: application of a dentin bonding agent (Scotchbond Adper, 3M ESPE, St Paul, MN, USA) in the pulp chamber (Group 1, n=60) versus no bonding intervention (Group 2, n=60), and five levels of intracanal medication (n=12/subgroup): Triple antibiotic paste (TAP), double antibiotic paste (DAB), calcium hydroxide (CH), modified triple antibiotic paste (TAPM), and Control (CTL). Color changes were measured over 28 days at multiple time points (1, 3, 7, 14, 21, and 28 days) using the CIEDE2000 formula to calculate the color difference (ΔE00) from baseline (T0). The ΔE00 quantifies the perceptible color difference between the initial and final tooth color, with lower values indicating less discoloration. The results were analyzed using repeated measures ANOVA-2 and post-hoc Holm-Sidak tests. The TAP subgroups, both with and without the bonding agent, exhibited the highest color variation. However, a pulp chamber seal with a bonding agent showed a protective effect against discoloration compared to no seal, even though complete prevention was not achieved. All groups demonstrated ΔE00 values beyond acceptable interpretation thresholds for clinical application, primarily driven by a reduction in lightness (L*) and a decrease in redness (a* value, shifting towards green). In conclusion, while the pulp chamber seal with a bonding agent mitigated TAP-induced discoloration, it did not eliminate it.

Resumo Este estudo in vitro avaliou adesivos dentinários na prevenção de alterações de cor após procedimentos endodônticos regenerativos. Cento e vinte incisivos bovinos foram preparados endodonticamente e aleatoriamente designados para um desenho com dois fatores principais: aplicação de agente adesivo (Scotchbond Adper, 3M ESPE, St Paul, MN, EUA) na câmara pulpar (Grupo 1, n=60) versus não intervenção adesiva (Grupo 2, n=60), e cinco níveis de medicação intracanal (n=12/subgrupo): pasta de triantibiótica (TAP), pasta diantibiótica (DAB), hidróxido de cálcio (CH), pasta triantibiótica modificada (TAPM) e Controle (CTL). Alterações cromáticas foram monitoradas por 28 dias em intervalos (1, 3, 7, 14, 21, e 28 dias), usando CIEDE2000 para calcular a diferença de cor (ΔE00) em relação a cor inicial. O ΔE00 quantifica a diferença entre a cor inicial e final do dente, com valores menores indicando menos descoloração. Os resultados foram analisados usando ANOVA-2 de medidas repetidas e teste posthoc de Holm-Sidak. Os grupos utilizando medicação TAP, com ou sem adesivo, possuíram as maiores variações cromática. Contudo, o uso do adesivo na câmara pulpar mostrou um efeito protetor contra descoloração, em comparação com a ausência do selamento adesivo, embora a prevenção completa não tenha sido alcançada. Todos os grupos demonstraram valores de ΔE00 além dos limiares aceitáveis para aplicação clínica, principalmente devido à redução na luminosidade (L*) e redução no vermelho (a*, deslocando-se em direção ao verde). Em conclusão, enquanto o selamento da câmara pulpar com um agente adesivo mitigou a descoloração induzida pelo TAP, mas não a eliminou completamente.

The effect of injectable platelet-rich fibrin and platelet-rich fibrin in regenerative endodontics: a comparative in vitro study

Abstract Objective To explore the feasibility of injectable platelet-rich fibrin (i-PRF) in regenerative endodontics by comparing the effect of i-PRF and platelet-rich fibrin (PRF) on the biological behavior and angiogenesis of human stem cells from the apical papilla (SCAPs). Methodology i-PRF and PRF were obtained from venous blood by two different centrifugation methods, followed by hematoxylin-eosin (HE) staining and scanning electron microscopy (SEM). Enzyme-linked immunosorbent assay (ELISA) was conducted to quantify the growth factors. SCAPs were cultured with different concentrations of i-PRF extract (i-PRFe) and PRF extract (PRFe), and the optimal concentrations were selected using the Cell Counting Kit-8 (CCK-8) assay. The cell proliferation and migration potentials of SCAPs were then observed using the CCK-8 and Transwell assays. Mineralization ability was detected by alizarin red staining (ARS), and angiogenesis ability was detected by tube formation assay. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the expression of genes related to mineralization and angiogenesis. The data were subjected to statistical analysis. Results i-PRF and PRF showed a similar three-dimensional fibrin structure, while i-PRF released a higher concentration of growth factors than PRF ( P <.05). 1/4× i-PRFe and 1/4× PRFe were selected as the optimal concentrations. The cell proliferation rate of the i-PRFe group was higher than that of the PRFe group ( P <.05), while no statistical difference was observed between them in terms of cell mitigation ( P >.05). More importantly, our results showed that i-PRFe had a stronger effect on SCAPs than PRFe in facilitating mineralization and angiogenesis, with the consistent result of RT-qPCR ( P <.05). Conclusion This study revealed that i-PRF released a higher concentration of growth factors and was superior to PRF in promoting proliferation, mineralization and angiogenesis of SCAPs, which indicates that i-PRF could be a promising biological scaffold for application in pulp regeneration.

Extrusão apical de irrigantes em dentes imaturos utilizando diferentes dispositivos de irrigação por pressão negativa / Apical extrusion of irrigants in immature teeth using different negative pressure irrigation devices

Objetivo: O objetivo deste estudo foi avaliar a extrusão apical de irrigantes em dentes imaturos simulados, comparando a irrigação convencional com outros dispositivos de irrigação por pressão negativa. Materiais e Métodos: 48 amostras de dentes imaturos simulados foram montadas em um modelo adaptado para conter o irrigante extravasado e distribuídas igualmente em 4 grupos (n=12) de acordo com o dispositivo de irrigação utilizado: Grupo Irrigação Convencional (IC), Grupo EndoVac (EV), Grupo Pulp Sucker (PS) e Grupo Ivac (IV). As amostras foram irrigadas com 15mL de solução irrigadora, sendo 10mL de NaOCl a 2,5% e 5mL de EDTA a 17% intercalados. As amostras foram pesadas em balança de precisão antes e depois dos procedimentos de irrigação, sendo a diferença entre os pesos final e inicial considerado o volume de irrigante extravasado. Os dados foram coletados e analisados estatisticamente pelos testes de Kruskal-wallis e exato de Fisher. Resultados: Os grupos que utilizaram pressão negativa promoveram significativamente menor volume de irrigante extravasado que o grupo IC (p<0,05), não havendo diferenças significativas quando comparados entre si (p>0,05). Houve diferenças significativas na associação entre os grupos e a extrusão de irrigante, sendo o grupo PS menos associado a extrusão de irrigante (p<0,005). Discussão: Estudos anteriores apontam os dispositivos de pressão negativa como opções seguras diante de extravasamento de irrigantes quando comparados à irrigação convencional. Conclusão: A irrigação convencional promoveu significativamente maior volume de extrusão de irrigante quando comparada aos dispositivos de irrigação por pressão negativa. O sistema PulpSucker mostrou extravasamento de irrigante em um número significativamente menor de amostras.

Aim: The aim of this study was to evaluate the apical extrusion of irrigants in simulated immature teeh, comparing convencional irrigation with other negative pressure irrigation devices. Materials and methods: 48 samples of simulated immature teeth were set up in an adapted model to contain the extravasated irrigant and evenly distributed into 4 groups (n=12) according to the device used: Convencional Irrigation Group (CI), EndoVac Group (EV), Pulp Sucker Group (PS) and Ivac Group (IV). The samples were irrigated with 15mL of irrigant solution, consisting of 10mL NaOCl 2,5% and 5mL EDTA 17%, in na alternating sequence. The samples' weights were measured using a precision scale before and after the irrigation procedures, with the difference between de final and initial weights considered the volume of extravasated irrigant. Data were collected and statistically analyzed by Kruskal-wallis and Fisher exact tests. Results: The groups that used negative pressure devices significantly promoted a lower volume of extruded irrigant than the CI group (p<0,05), with no significant differences between the negative pressure groups (p>0,05). There were signficant differences in the association between the groups and irrigant extrusion, with the PS group showing significantly less association with irrigant extrusion (p<0,005). Discussion: Previous studies have indicated that negative pressure devices are safe alternatives to convencional irrigation when considering irrigant extrusion. Conclusion: Conventional irrigation promoted a significantly greater volume of irrigant extrusion when compared to negative pressure irrigation devices. The PulpSucker system showed irrigant extravasation in significantly fewer samples.

Técnica intralesional en endodoncia con injerto aloplástico transforamen apical / Intralesional endodontic technique with apical transforaminal alloplastic graft

La endodoncia es preventiva cuando sacrifica la totalidad o parte del tejido pulpar vital para evitar una posible invasión microbiana a los tejidos de so- porte del diente. Esta endodoncia pasa a ser curativa cuando se instala en ellos la noxa bacteriana, donde la farmacoterapéutica local alcanza una relevancia significativa. Cuando se realiza la obturación del conducto radicu- lar con un biomaterial no reabsorbible y se invade el periodonto, la posterior reparación posendodóntica solo se realiza a expensas del hueso medular y se impide el cierre de la trayectoria final del conducto radicular con tejido mineralizado de origen perio- dontal (cemento secundario). Aplicando una técnica intralesional, ya sea transfo- ramen apical o utilizando como vector un trayecto fistuloso, se viabiliza una terapia intralesional con biomateriales biodegradables y bioactivos. Se obtiene así, mayor calidad y rapidez en la regeneración ad integrum de los tejidos lesionados, por medio de la activación de la fase defensiva-constructiva y el cierre del foramen apical con tejido mineralizado. Los tejidos afectados curan con una cinética significativamente más rápida, sin recurrir a la cirugía complementaria de la endodoncia, procedimiento invasivo asociado con ciertos efectos adversos (AU)

Endodontics is preventive when it sacrifices all or part of the vital pulp tissue to avoid possible microbial invasion of the supporting tissues of the tooth. This endodontics becomes curative when bacterial noxa settles in them, where local pharmacotherapeutics reaches significant relevance. When root canal obturation is performed with a non-resorbable biomaterial and the periodontium is invaded, the subsequent postendodontic repair is only performed at the expense of the medullary bone and the closure of the final trajectory of the root canal with mineralized tissue of periodontal origin is prevented. (Secondary cement). Applying an intralesional technique, be it apical transformation or using a fistulous tract as a vector, intralesional therapy with biodegradable and bioactive biomaterials becomes viable. In this way, greater quality and speed is obtained in the ad integrum regeneration of injured tissues, through the activation of the defensive-constructive phase and the closure of the apical foramen with mineralized tissue. Affected tissues heal with significantly faster kinetics, without resorting to complementary endodontic surgery, an invasive procedure associated with certain adverse effects (AU)

Evolución histórica del tratamiento en dientes permanentes inmaduros necróticos / Historical evolution of treatment in necrotic immature permanent teeth i: en

El tratamiento de dientes permanentes inmaduros necróticos constituye un desafío en la odontopediatría, y son múltiples las opciones terapéuticas propuestas para solucionar esta problemática. A tales efectos se realizó el presente estudio con el objetivo de exponer la evolución histórica de dicho tratamiento, para lo cual se efectuó una exhaustiva búsqueda bibliográfica. Se consideró como método general de la investigación el dialéctico-materialista y, de manera particular, los métodos de revisión documental histórico-lógico, de análisis-síntesis e inductivo-deductivo. A partir de determinados hitos históricos se establecieron 3 etapas, cada una de ellas con sus aportes y limitaciones; asimismo, se identificaron las regularidades y tendencias, así como los fundamentos que sustentan la necesidad de continuar investigando sobre nuevos enfoques terapéuticos.

The treatment of necrotic immature permanent teeth constitutes a challenge in the pediatric dentistry, and there are multiple therapeutic options to solve this problem. To such effects the present investigation was carried out with the objective of exposing the historical evolution of this treatment, reason why an exhaustive literature review was carried out. The dialectical-materialistic method was assumed as the general one of the investigation and in a particular way, the historical-logical, analysis-synthesis and inductive-deductive methods of documental review. Three stages were established based on certain historical landmarks, each one with its contributions and limitations; also, regularities and tendencies were identified, as well as the foundations that sustain the necessity to continue investigating on new therapeutic approaches.

Research progress on in vivo models for stem cell-based pulp regeneration / 口腔疾病防治

@#Basic research on pulp regeneration requires in vivo experiments. The PubMed database was searched for in vivo models of stem cell-based pulp regeneration using the following keywords: "pulp regeneration", "stem cell" and "animal model". The retrieved models were classified into ectopic, semiorthotopic and orthotopic regeneration models and their characteristics and clinical values were reviewed. This literature review indicated that the ectopic regeneration model is the most widely used model for the simple steps. However, this model does not accurately capture clinical situations. The semiorthotopic regeneration model, which is an improvement of the ectopic regeneration model, can create a more realistic regeneration environment. The orthotopic regeneration model can simulate clinical procedures that more closely resemble application, but it is less commonly used for difficult operations and long experimental periods. The applicability of the above three animal models depend on the stage of the animal experiment: the ectopic regeneration model is suitable to test the regenerative effect and biocompatibility of the implant complex; the semiorthotopic regeneration model is suitable to more persuasively evaluate the regeneration effect of the implant complex; and the orthotopic regeneration model is suitable to confirm the regeneration effect and practicability of the regenerative implant complex prior to clinical study.

Clinical and Radiographic Success Rates of Pulpotomies in Primary Molars Treated with Formocresol, BiodentineTM, and Endo Repair: A Randomized Clinical Trial

ABSTRACT Objective: To compare the clinical and radiographic success rates of formocresol, BiodentineTM, and Endo Repair agents in primary molars after 12 months. Material and Methods: This randomized double-blind clinical trial was conducted on healthy children referred to the Department of Pediatric Dentistry, Kerman, Iran, in 2018. One hundred twenty children (human primary molar teeth) aged 3-9 years were selected and randomly divided into three interventions (with pulpotomy medicament agents), including formocresol, BiodentineTM, and Endo Repair. All pulpotomized teeth were restored using stainless steel crowns and evaluated clinically and radiographically during a 12-month follow-up. Fisher exact test was used to determine the association of categorical variables and the data were analysed with SPSS 25. Results: All the available teeth in formocresol and BiodentineTM groups obtained clinical success, whereas 62.5% of the Endo Repair group was successful in this regard. Radiographic success rates of the formocresol, BiodentineTM, and Endo Repair groups were 94.7%, 70%, and 28.1% after a 12-month follow-up, respectively. Moreover, pulp canal obliteration was observed in 26.3%, 25%, and 12.5% of the formocresol, BiodentineTM, and Endo Repair groups. Conclusion: This study reported a high rate of clinical success using both BiodentineTM and formocresol pulpotomy techniques. However, the radiographic success rate of formocresol was higher than that of BiodentineTM, and Endo Repair was not considered a suitable pulpotomy medicament agent.

Spectrophotometric analysis of internal bleaching of traumatized teeth with coronal discoloration following regenerative endodontic procedures

Aim: The objective of this study was to describe a case series concerning internal bleaching of anterior traumatized teeth that underwent regenerative endodontic procedures (REP). Methods: Seven non-vital maxillary anterior teeth discolored after regenerative endodontic procedures were included and divided into two groups according to the medication protocol used in the REP: (1) Triple antibiotic paste (TAP) group (n=4); (2) Calcium hydroxide and 2% chlorhexidine gel (HC+CHX) (n=3). The bleaching technique used was walking bleach, where sodium perborate associated with distilled water was used. Bleaching agent was replaced weekly until the darkened tooth was slightly lighter than the adjacent tooth. The color was recorded with the aid of a digital spectrophotometer in two moments (T1: prior the first session of bleaching, T2: fourteen days after the last session of bleaching). The change in color after the procedure (ΔE) was calculated and reported in a descriptive analysis. Results: The ΔE for all teeth showed color differences exceeding the perceptibility threshold (ΔE > 3.7). Both groups showed similar ΔE (TAP: 18.3 ± 11.5; HC+CHX: 14 ± 11.2) at the end of the treatment. The average number of sessions needed to achieve satisfactory results was 1.7 ± 0.6 for HC+CHX group and 2.3 ± 0.5 for TAP group. Conclusion: Internal bleaching with sodium perborate associated with distilled water is effective in treating discolored teeth after regenerative endodontic procedures

Do alternative scaffolds used in regenerative endodontics promote better root development than that achieved with blood clots?

Abstract The aim of this integrative review was to identify whether alternative scaffolds used in regenerative endodontics contribute to better root development, in relation to the increase in root length and thickness of dentin walls, compared with blood clot (BC) scaffolds. The literature search was conducted in PubMed, SciELO and Lilacs databases, using descriptors related to the topic. After applying the eligibility criteria, 11 articles were selected and analyzed according to the proposed aim. Five clinical and six in vivo studies, conducted in animals, compared different types of alternative scaffolds with BCs, with emphasis on platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). All scaffolds, alternative or BC, promoted an increase in root length and dentin wall thickness, with varying percentages of increase between studies. In general, there was a significant increase in root length and dentin thickness promoted by PRF and PRP scaffolds, compared with BC. It was concluded that the majority of the scaffolds tested contributed to the increase in root length and thickness of dentin walls, with emphasis on PRF and PRP.

Resumo O objetivo desta revisão integrativa foi identificar se os scaffolds alternativos utilizados em endodontia regenerativa contribuem para um melhor desenvolvimento radicular, em relação ao aumento do comprimento e espessura das paredes da dentina, em comparação com os scaffolds de coágulo sanguíneo (BC). A pesquisa bibliográfica foi realizada nas bases de dados PubMed, SciELO e Lilacs, utilizando descritores relacionados ao tema. Após a aplicação dos critérios de elegibilidade, 11 artigos foram selecionados e analisados de acordo com o objetivo proposto. Cinco estudos clínicos e seis in vivo, realizados em animais, compararam diferentes tipos de scaffolds alternativos com BCs, com ênfase no plasma rico em plaquetas (PRP) e fibrina rica em plaquetas (PRF). Todos os scaffolds, alternativos ou BC, promoveram um aumento no comprimento da raiz e na espessura da parede dentinária, com percentuais variáveis de aumento entre os estudos. Em geral, houve um aumento significativo do comprimento da raiz e da espessura da dentina promovido pelos scaffolds PRF e PRP, em comparação com a BC. Concluiu-se que a maioria dos scaffolds testados contribuiu para o aumento do comprimento das raízes e da espessura das paredes dentinárias, com ênfase em PRF e PRP.

A segmental root development as an unusual healing response to the revitalization of mandibular second premolar

A 15-year-old patient reported persistent pain in the left mandibular second premolar (#35) following a traumatic bite 3 months ago. Clinical examination revealed a fractured central cusp suggestive of dens evaginatus. Intraoral periapical radiograph revealed an immature permanent tooth with a periapical radiolucency. A diagnosis of pulp necrosis with symptomatic apical periodontitis was made. The tooth was treated according to the revised guidelines of regenerative endodontic procedure by the American Association of Endodontics. The follow-up evaluation revealed a complete resolution of periapical pathology. A detached radiopaque tissue was appreciated at the 12-month follow-up. It resembled a broken root tip at the 24-month follow-up. Both the main root body and disjointed root tip developed independently. A cone-beam computed tomography evaluation at the 36-month follow-up confirmed the segmented development of the apical root tip.

Combined effects of bone morphogenetic protein-7 and mineral trioxide aggregate on the proliferation, migration, and differentiation of human dental pulp stem cells

Abstract Bioactive molecules present the potential to be used along with biomaterials in vital pulp therapy and regenerative endodontic treatment. Objective The aim of this study was to assess the effects of the combined use of bone morphogenetic protein-7 (BMP-7) and mineral trioxide aggregate (MTA) on the proliferation, migration, and differentiation of human dental pulp stem cells (DPSCs). Methodology For the proliferation analysis, DPSCs were incubated with a growth medium and treated with MTA and/or BMP-7 at different concentrations. For the following analyses, DPSCs were incubated with a differentiation medium and treated with MTA and/or BMP-7. Moreover, there were groups in which DPSCs were incubated with the growth medium (control), the differentiation medium, or DMEM/F12 containing fetal bovine serum, and not treated with MTA or BMP-7. Cell proliferation was analyzed using the WST-1 assay. The odontogenic/osteogenic differentiation was evaluated by immunocytochemistry, alkaline phosphatase (ALP) activity assay, alizarin red staining, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cell migration was evaluated using a wound-healing assay. Data were analyzed using analysis of variance and Tukey test (p=0.05). Results The use of BMP-7 with MTA presented no significant effect on cell proliferation in comparison with the treatment with MTA alone (p>0.05), but showed higher ALP activity, increased mineralization, and higher expression of DMP1 and DSPP when compared with other groups (p<0.05). Nestin expression was higher in the control group than in groups treated with MTA and/or BMP-7 (p<0.05). The cell migration rate increased after treatment with MTA when compared with other groups in all periods of time (p<0.05). At 72 hours, the wound area was smaller in groups treated with MTA and/or BMP-7 than in the control group (p<0.05). Conclusion The use of BMP-7 with MTA increased odontogenic/osteogenic differentiation without adversely affecting proliferation and migration of DPSCs. The use of BMP-7 with MTA may improve treatment outcomes by increasing repair and regeneration capacity of DPSCs.

Regenerative endodontics model in immature infected rat molars using two step protocol

Aim: to develop a model for regenerative endodontics using newly-weaned Wistar rats immature molars with pulp necrosis to histologically describe the evolution of apical tissues following treatment with a bi-antibiotic paste, induced bloodclot formation and MTA. Methods: Ten 25-day-old female Wistar rats were divided into an initial control group (Ci) and two experimental groups in which pulp necrosis was experimentally induced on the left mandibular first molar by exposing the pulp chamber and leaving it open to the oral environment. One of the experimental groups was left untreated (E1) while the other was submitted to a protocol of regenerative endodontics 10 days thereafter (E2). Fifteen days after placement of a bi-antibiotic paste, bleeding was induced into the root canal space and MTA was placed upon. Animals were euthanized 30 days later. Right mandibular first molars served as an 80-day-old final control group (Cf). Each hemimandible was histologically processed to analyse parameters associated with root development. Statistical analysis was carried by means of ANOVA; p values below 0.05 were considered statistically significant. Results: baseline (i.e. 25-days old) mean root length and apical diameter of the distal root canal were 1.84±0.25 and 0.38±0.02mm respectively. Following the regenerative endodontic protocol, cells lining the walls of the root canal and significant increase to both length (2.37±0.22mm) and diameter (0.32±0.03 mm) were observed. Conclusions: newly-weaned Wistar rats serve as a suitable model to evaluate regenerative endodontic protocols. However, further research is needed in order to disclose the nature of the cells and/or cell mediators involved

Procedimentos regenerativos endodônticos com clorexidina a 2% e hidróxido de cálcio: relato de caso / Endodontic regenerative procedures with 2% chlorhexidine and calcium hydroxide: case report

Introdução: Muitas substâncias têm sido utilizadas como irrigantes e curativos intracanal nos tratamentos de dentes com rizogênese incompleta, visando obter a regeneração pulpar. A clorexidina a 2% em associação com hidróxido de cálcio P.A. pode ser uma alternativa. Métodos: No presente caso clínico, o dente #45 com periodontite apical, em um paciente com 13 anos de idade, foi tratado com solução de clorexidina a 2% como irrigante. A clorexidina na forma de gel a 2% foi utilizada como auxiliar da instrumentação e, em associação com o hidróxido de cálcio, foi utilizada como curativo durante 14 dias. Após esse período, o canal foi irrigado com solução fisiológica e, sob anestesia alveolar mandibular, uma lima K #70 foi utilizada ultrapassando levemente o ápice, para causar sangramento. Após observar que o sangue dentro dos canais alcançou a porção cervical, o cimento biocerâmico MTA Branco foi colocado na porção cervical do canal. Resultados: A apicificação e o desenvolvimento da raiz em comprimento e largura puderam ser observados já no controle de três meses, e continuaram até a última revisão, no controle de um ano. Alterações de cor não foram observadas nese período de acompanhamento. Conclusões: A clorexidina associada ao hidróxido de cálcio pode ser uma alternativa aos procedimentos de regeneração pulpar (AU).

Introduction: Many substances have been used as irrigating solutions to promote pulp regeneration and root development in teeth with incomplete rhizogenesis. The use of 2% chlorhexidine as an irrigating solution in association with Calcium Hydroxide could be an alternative. Methods: In the case of the patient, a 13-year-old boy, here presented, tooth 45 with apical periodontitis was treated with 2% Chlorhexidine solution as irrigant adjuvant to instrumentation, in association with Calcium Hydroxide used as a dressing for 14 days. After this period, the canal was cleaned with a physiological solution and under mandibular alveolar anesthesia, a # 70 K file was used slightly over the apex to cause bleeding. After observing that blood inside the canals had reached the cervical portion. White MTA was placed in the cervical portion of the canal. Results: Induced apexification and development of increasing root length and width could already be observed in the three-month control exam, and this continued until the last review in the one-year control exam. No color changes were observed in this follow-up period. Conclusions: Chlorhexidine and calcium hydroxide could be used as an alternative to pulp regeneration procedures (AU).

The influence of the particle's size on the setting reaction of sol-gel derived calcium silicate particles / A influência do tamanho de partícula na reação de presa de cimentos de silicate de cálcio produzidos por sol-gel

Introduction: This study aims to analyze the influence of particles size of sol-gel derived calcium silicate particles in the setting reaction of bioactive endodontic cements. Materials and Methods: Sol-gel derived calcium silicate particles were synthesized and sieved to separate the particles in different sizes: CS400, CS200, and CS100. A commercial MTA (Control) was used as control. The particle size and the specific surface area were assessed by laser diffraction and nitrogen adsorption. The cements were prepared with water as the liquid for the reaction. The setting time was conducted according to ISO 6876, and the setting kinetics was analyzed by Fourier trans-formed infrared spectroscopy (FTIR) at different time points between 120s to 72h. Results: The particle size varied from 9.45µm (CS400 ) to 31.01 (Control). The higher specific surface area valuer reached 15.14g/cm2 in the CS400. The smallest particle sizes, the higher specific surface area, and the lowest setting time were found for CS400 (p < 0.05). Control presented the highest setting time (p < 0.05). The FTIR analyses showed the differences in materials structure over time, with faster hydration and crystallization for CS400. The setting kinetics was slower for Control even when compared to a sol-gel derived group with similar particle size. Conclusion:The route of synthesis and the particle size influences the setting reaction of calcium silicate-based cements. The reduction of particle size for sol-gel derived calcium silicates lead to the acceleration of the setting reaction of the produced bioactive endodontic cement.

Introdução: Este estudo tem como objetivo analisar a influência do tamanho de partículas de silicato de cálcio derivadas de sol-gel na reação de presa de cimentos endodônticos bioativos. Materiais e Métodos: Partículas de silicato de cálcio derivadas de sol-gel foram sintetizadas e peneiradas para separar as partículas em diferentes tamanhos: CS400, CS200 e CS100. Um MTA comercial (Controle) foi usado como controle. O tamanho das partículas e a área superficial específica foram avaliados por difração a laser e adsorção de nitrogênio. Os cimentos foram preparados com água como líquido para a reação. O tempo de presa foi conduzido de acordo com a ISO 6876, e a cinética de presa foi analisada por espectroscopia de infravermelho transformada de Fourier (FTIR) em diferentes pontos de tempo entre 120s a 72h. Resultados: O tamanho de partícula variou entre 9,45µm (CS400) e 31,01 (Controle). A maior área de superfície foi encontrada nas partículas do grupo CS400 (15.14g/cm2). Os menores tamanhos de partícula, a maior área de superfície específica e o menor tempo de presa foram encontrados para CS400 (p < 0,05). O Control apresentou o maior tempo de presa (p < 0,05). As análises de FTIR mostraram as diferenças na estrutura dos materiais ao longo do tempo, com hidratação e cristalização mais rápidas para CS400. A cinética de presa foi mais lenta para Control mesmo quando comparado a um grupo derivado de sol-gel com tamanho de partícula semelhante. Conclusão: A rota de síntese e o tamanho das partículas influenciam a reação de endurecimento dos cimentos à base de silicato de cálcio. A redução do tamanho de partícula para silicatos de cálcio derivados de sol-gel leva à aceleração da reação de pega do cimento endodôntico bioativo produzido.

Different techniques for the treatment of teeth with an incomplete root development and pulp necrosis: a systematic review / Diferentes técnicas para o tratamento de dentes com rizogênese incompleta e necrose pulpar: uma revisão sistemática

Introduction: The objective of this systematic review was to compare the apexification techniques of calcium hydroxide (Ca(OH)2), or mineral trioxide aggregate (MTA), with the pulp regeneration technique, using cohort studies, and non-randomized and randomized clinical trials. Methods: The methodology was based on electronic research in the following databases: PubMed, MEDLINE, Google Scholar, SciELO, and LILACS. In addition, a manual search was carried out using the references that were listed in the articles found. Results: A total of 403 potentially eligible studies were found, with seven being included in the inclusion criteria of this systematic review. The seven studies involved a total of 312 teeth. The minimum time of a follow-up period was 12 months. The irrigation solution most used was sodium hypochlorite, for both of the apexification and revascularization techniques. The medication commonly chosen in the apexification groups was Ca(OH)2, with antibiotic triple paste in the revascularization groups. The clinical rate of success in the groups treated with revascularization varied from 76% to 100%, while in the groups treated with apexification, it ranged from 68% to 100%. Only two studies reached a success rate equal to 100%. Conclusions: Variable levels of evidence were observed in relation to the treatments. However, it was confirmed that revascularization is an excellent option since its outcomes produced a greater gain of thickness and root length, besides developing a decrease in the apical foramen.

Introdução: O objetivo desta revisão sistemática foi comparar as técnicas de apexificação, com hidróxido de cálcio (Ca(OH)2) ou agregado trióxido mineral (MTA), com a técnica de regeneração pulpar, utilizando estudos coorte, ensaio clínico não randomizado e randomizado. Métodos: A metodologia foi baseada em pesquisa eletrônica nas seguintes bases de dados: PubMed, MEDLINE, Google Acadêmico, SciELO e LILACS. Além disso, foi realizada uma pesquisa manual utilizando as referências listadas nos artigos encontrados. Resultados: Foram encontrados 403 estudos potencialmente elegíveis, sendo sete incluídos nos critérios de inclusão desta revisão sistemática. Os sete estudos envolveram um total de 312 dentes. O tempo mínimo de um período de acompanhamento foi de 12 meses. A solução de irrigação mais utilizada foi o hipoclorito de sódio, para as técnicas de apexificação e revascularização. O medicamento comumente escolhido nos grupos de apexificação foi o Ca(OH)2, com pasta tripla antibiótica nos grupos de revascularização. A taxa clínica de sucesso nos grupos tratados com revascularização variou de 76% a 100%, enquanto nos grupos tratados com apexificação variou de 68% a 100%. Apenas dois estudos atingiram uma taxa de sucesso igual a 100%. Conclusões: Níveis variáveis de evidência foram observados em relação aos tratamentos. No entanto, confirmou-se que a revascularização é uma excelente opção, pois seus desfechos produzem maior ganho de espessura e comprimento radicular, além de diminuir o forame apical.

Algunos fundamentos de la endodoncia regenerativa con células madre en el diente permanente inmaduro no vital / Some basics of the regenerative endodontics with stem cells in the non-vital immature permanent tooth

La endodoncia regenerativa comprende un conjunto de procedimientos biológicos que se efectúan en los dientes permanentes con ápice no formado y necrosis pulpar, cuyo fin es sustituir los tejidos dañados, incluidas la dentina y la estructura radicular, así como las células del complejo pulpodentinario. En este artículo se describen las bases celulares y moleculares de esta terapia, sustentada en una compleja interacción entre las células madre dentales de la papila apical, los factores de crecimiento y los biomateriales con el microambiente donde se va a restablecer. Asimismo, se argumenta cómo las condiciones ambientales en las que se lleva a cabo el proceso terapéutico influyen en la regeneración, con una función esencial en la regulación de la diferenciación de los tejidos.

The regenerative endodontics comprises a group of biological procedures that are made in the permanent teeth with non-formed apex and pulpar necrosis whose end is to substitute the damaged tissues, including the dentine and radicular structure, as well as the cells of the dentin pulp complex. The cellular and molecular basis of this therapy are described in this work, sustained in a complex interaction between the dental stem cells of the apical papilla, the growth factors and biomaterials with the microenvironment where it will be recover. Likewise, it was argued how the environmental conditions in which the therapeutic process is carried out influence in the regeneration, with an essential function in the regulation of the differentiation of tissues.

Tratamiento regenerativo de lesión interproximal consecuente a fractura del tercio medio en diente permanente joven / Regenerative treatment of interproximal lesion following middle third fracture in a young permanent tooth

Se presenta un caso clínico de fractura radicular del tercio medio, de pieza 2.1 con desplazamiento de los cabos de fractura. Es tratado con un novedoso procedimiento terapéutico, mediante la utilización de un biomaterial de tercera generación osteoconductor, osteogénico y osteoinductor. Se obtiene la reparación del tejido conectivo interproximal y la formación de tejido calcificado (AU)

We present a clinical case of root fracture of the middle third, piece 2.1 with displacement of the fracture ends. It is treated with a novel therapeutic procedure, using a thirdgeneration osteoconductive, osteogenic and osteoinductive biomaterial. Interproximal connective tissue repair and calcified tissue formation are obtained (AU)

Tratamiento del Diente Permanente Necrótico. Un Cambio de Paradigma en el Campo de la Endodoncia / Treatment of the Necrotic Permanent Tooth. A Paradigm Shift in Endodontics

RESUMEN: El tratamiento de dientes inmaduros necróticos es hoy un gran desafío clínico. La ausencia de cierre del ápice y el reducido grosor de las paredes de la dentina hacen que el tratamiento endodóntico del diente sea difícil e impredecible. Tradicionalmente, estos dientes han sido tratados con apexificación y obturación del canal radicular, sin embargo, con este tratamiento el diente permanece desvitalizado y con paredes de dentina frágiles y cortas, lo que compromete su pronóstico. La endodoncia regenerativa, por el contrario, busca revitalizar el diente e inducir una maduración de la raíz, y se basa en la utilización de las células madre mesenquimales presentes en la región periapical, los factores de crecimiento presentes en la dentina y un andamio que permite el crecimiento de tejido nuevo al interior del canal. Los resultados clínicos son alentadores, ya que en general existe maduración de la raíz y revascularización del diente, sin embargo, el tejido neoformado es tejido de tipo reparativo y, a excepción de estudios ocasionales, no se ha observado regeneración de dentina y pulpa. La endodoncia regenerativa se originó para tratar dientes inmaduros necróticos. Sin embargo, recientemente, estudios preliminares han expandido la aplicación de la endodoncia regenerativa a dientes maduros necróticos, es decir, en pacientes adultos. Los resultados clínicos son positivos y similares a los del diente inmaduro, si n embargo, la investigación referente a la revitalización de dientes maduros se encuentra en etapas tempranas y requiere de un mayor nivel de evidencia antes de ser ofrecida sistemáticamente como terapia a pacientes adultos. Los beneficios potenciales justifican mayor investigación al respecto. Este artículo resume la evidencia científica disponible con respecto a la revitalización de dientes inmaduros y maduros necróticos, sus fundamentos biológicos, los resultados esperados y limitaciones, así como el protocolo clínico.

ABSTRACT: Nowadays, the treatment of immature necrotic teeth is an important clinical challenge. The absence of apex closure and low thickness of the dentin walls, make endodontic treatment unpredictable and difficult. Traditionally, these teeth have been treated with apexification and obturation of the root canal. As a result of this treatment, the tooth remains devitalized and with fragile and short dentin walls, which compromises its prognosis. Regenerative endodontics, on the other hand, seeks to revitalize the tooth and induce root maturation, and is based on the use of mesenchymal stem cells present in the periapical tissues, growth factors present in the dentin and a scaffold that allows growth of new tissue in the root ca- nal. The clinical results are encouraging, since generally, there is root maturation and revascularization of the tooth. However, the newly formed tissue is reparative tissue and with the exception of some studies, no regeneration of dentin and pulp has been reported. Regenerative endodontics emerged to treat necrotic immature teeth. However, recently, preliminary studies have applied regenerative endodontics in mature necrotic teeth, in adult patients. Preliminary results are positive and are similar to those of immature teeth. Nevertheless, research regarding the revitalization of mature teeth is in the early stages and requires further evidence before being systematically administered as therapy in adult patients. However, the potential benefits justify further research in this regard. This article summarizes the available scientific evidence regarding the revitalization of immature and mature necrotic teeth, their biological basis, the expected results and limitations, as well as the clinical protocols for each case.

12-year follow-up of regenerative endodontic treatment of immature permanent upper incisors with acute abscess

Abstract This case report discusses the endodontic treatment of a 7-year-old girl who suffered trauma (intrusion) to the immature upper central incisors secondary to a fall from a bicycle. Thirty days after the accident the patient was brought by her mother for clinical and radiographic assessment with a chief complaint of swelling and tenderness to percussion and palpation. Acute apical abscess associated with immature teeth were diagnosed. A decision was made to perform regenerative endodontic treatment. Access cavities were made and the root canals were disinfected by irrigation with 2.5% sodium hypochlorite. Final irrigation was performed with 17% EDTA. Due to pain and presence of secretions, 2% chlorhexidine gel was applied as an intracanal medicament. Seven days later, at the second visit, the root canals were once again disinfected and the canals of the right and left permanent upper central incisors were filled with double antibiotic paste (metronidazole/ciprofloxacin) and calcium hydroxide paste, respectively. Zinc oxide was mixed in both pastes. At the third visit, after 21 more days, the pastes were removed and the periapical areas were stimulated with a #80 K-file to encourage clot formation within the pulp cavities. A mineral trioxide aggregate (MTA) paste cervical plug was placed and the teeth were restored with glass ionomer cement. Radiographs and CBCT scans demonstrated complete root formations. The patient has been followed for 12 years, with evidence of clinical success throughout.

Resumo Este relato de caso discute o tratamento endodôntico de uma menina de 7 anos que sofreu trauma nos incisivos centrais superiores imaturos, após queda de bicicleta. Trinta dias após o acidente, a paciente foi levada pela mãe para avaliação clínica e radiográfica com queixa principal de inchaço e sensibilidade à percussão e palpação. Foram diagnosticados abscessos apicais agudos em ambos os dentes. Foi decidido por realizar o tratamento endodôntico regenerativo. Após acessos coronários, os canais radiculares foram submetidos à protocolos de antissepsia com auxílio de irrigação com hipoclorito de sódio a 2,5% e EDTA 17%. Devido à dor e presença de secreções, foi utilizada medicação intracanal com clorexidina gel 2% por 7 dias. Na segunda sessão, os canais radiculares foram novamente submetidos aos procedimentos de antissepsia e os canais dos incisivos centrais superiores permanentes direito e esquerdo foram preenchidos com pasta antibiótica dupla (Metronidazol / Ciprofloxacina) e pasta de hidróxido de cálcio, respectivamente. Em ambas as pastas foi adicionado o óxido de zinco. Na terceira sessão, após mais 21 dias, as pastas foram removidas e as regiões periapicais foram estimuladas com lima K nº 80 para incentivar a formação de coágulos sanguíneos no interior das cavidades pulpares. Tampões cervicais de MTA foram adaptados e os dentes restaurados com cimento de ionômero de vidro resinoso. Radiografias e tomografias computadorizadas demonstraram formações radiculares completas. A paciente é acompanhada há 12 anos, com evidências clínicas e radiográficas de sucesso.