Apical Periodontitis Healing Following Treatment is Impacted by Root Canal Sealer Composition: An in Vivo and in Vitro Investigation

Abstract Objective: To evaluate the periapical healing following root canal treatment in teeth with apical periodontitis (in vivo) and the cytotoxic potential of root canal sealers in vitro. Material and Methods: Apical periodontitis was induced in 60 dogs' teeth and root canals were filled with Sealapex (40 roots), EndoREZ (40 roots), intracanal dressing (20 roots), or left untreated (20 roots). After 30 and 90 days, histopathological analyses were made. In vitro, J774.1 macrophages were stimulated with root canal sealers extracts, cytotoxicity was assessed using lactate dehydrogenase assay, and qRT-PCR was used to analyze TNF-α gene expression. Results: In vivo, smaller apical periodontitis and lower inflammatory cell infiltrate were found in teeth treated with Sealapex compared to EndoREZ. In vitro, EndoREZ was cytotoxic and induced TNF-α gene expression by macrophages differently from Sealapex. Conclusion: Sealapex allowed improved tissue repair following root canal treatment in teeth with apical periodontitis compared to EndoREZ. Synthesis of TNF-α induced by LPS was enhanced by EndoREZ, whereas Sealapex prevented pro-inflammatory gene expression (AU).

Root canal treatment of an immature dens invaginatus with apical periodontitis: a case report.

The purpose of this paper was to describe the case of an 11-year-old patient who presented a dens invaginatus, detected in the permanent maxillary left lateral incisor, with an immature open apex and extensive apical periodontitis and sinus tract. The mineralized invaginated barrier was removed, and a nonsurgical root canal treatment was performed using both calcium hydroxide as a root canal dressing to stimulate apexification and a mineral trioxide aggregate (MTA) plug to permit root canal filling. After a 14-month period of root canal dressing changes, no evidence of apical periodontitis was observed, and the MTA plug was placed in the root canal's apical portion. The root canal filling was performed using the thermoplasticized gutta-percha technique. At the 12-month follow-up, complete radiographic periapical healing, characterized by bone formation in the area around the tooth apex, and no clinical or radiographic evidence of refractory apical periodontitis were detected.

Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs' teeth with apical periodontitis.

OBJECTIVE: The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs' teeth with apical periodontitis. STUDY DESIGN: Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn's tests (alpha = 0.05). RESULTS: Although statistically significant difference was found only for the inflammatory infiltrate (P < .05), Group 1 presented more exuberant mineralized formations, more structured apical and periapical connective tissue, and a more advanced repair process than Group 2. CONCLUSION: From the histological observations, sodium hypochlorite irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary.

Apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing on root canal disinfection in dog teeth.

OBJECTIVE: The aim of this study was to compare in vivo the efficacy of 2 root canal disinfection techniques (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dog teeth with apical periodontitis. STUDY DESIGN: Two groups of root canals with pulp necrosis and apical periodontitis were evaluated according to the disinfection technique: group 1: apical negative pressure irrigation (EndoVac system); and group 2: apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. The first sample (S1) was collected after lesions were radiographically visible, and the second sample (S2) was collected after apical negative pressure irrigation (group 1) or conventional irrigation/triantibiotic dressing (group 2). All samples were seeded in a culture medium for anaerobic bacteria. Colony-forming unit counts were analyzed statistically by the Mann-Whitney test (alpha = .05). RESULTS: Microorganisms were present in 100% of canals of both groups in S1. In S2, microorganisms were absent in 88.6% of group 1's canals and 78.28% of group 2's canals. There was no significant difference between the groups in either S1 (P = .0963) or S2 (P = .0566). There was significant (P < .05) bacterial reduction from S1 to S2 in both groups. CONCLUSION: In immature teeth with apical periodontitis, use of the EndoVac system can be considered to be a promising disinfection protocol, because it provided similar bacterial reduction to that of apical positive pressure irrigation (conventional irrigation) plus intracanal dressing with the triantibiotic paste, and the use of intracanal antibiotics might not be necessary.

A comparison study of periapical repair in dogs' teeth using RoekoSeal and AH plus root canal sealers: a histopathological evaluation.

The objective of the study was to evaluate the biocompatibility of RoekoSeal sealer Roeko (Dental Products, Langenau, Germany) with the periapical tissues of dogs and compare it with AH Plus sealer (Dentsply/De Trey, Konstanz, Germany). The pulps of 32 root canals were removed, the apical cementum layer perforated, the biomechanical preparation performed, and the root canals filled by lateral condensation technique. Ninety days after the surgery, the animals were euthanized, the bone with teeth removed, and the samples prepared for histopathological analysis. In group 1 (RoekoSeal Automix), deposition of mineralized tissue was observed, with complete newly mineralized apical formed tissue in 43.8% and partial sealing in 56.2%. In group 2 (AH Plus), in 12.5% there was complete newly mineralized apical formed tissue, in 75% the sealing was partial, and in 12.5% there was no sealing (p < 0.05). There were no differences between the groups in relation to the inflammatory infiltrate; thickness of the periodontal ligament; and the resorption of dentin, cementum or bone (p > 0.05).

Propriedades físico-químicas da água potencialmente oxidativa e sua capacidade de remoção da camada residual de instrumentação / Physico-chemical properties of the potentially oxidative water and its capability of the instrumentation residual layer remotion

O objetivo deste estudo foi elaborar a água potencialmente oxidativa (APO) e analisar algumas de suas propriedades físico-químicas: pH, densidade, tensão superficial, ângulo de contato, condutividade e potencial ação de oxidorredução. Além disso, buscou-se comparar sua capacidade de remoção de matéria orgânica e inorgânica à do hipoclorito de sódio a 1% associado ao EDTA a 17%. A APO foi obtida por processo de eletrólise, e foram determinadas suas propriedades físico-químicas em 0, 1, 3, 5 e 7 dias. Para avaliar a capacidade de remoção da camada residual de instrumentação utilizaram-se 30 pré-molares unirradiculares extraídos de humanos, por razões periodontais divididos em três grupos: controle positivo (NaOCL+EDTA), controle negativo (água destilada) e experimental (APO). Após o preparo, as amostras foram observadas sob microscopia eletrônica com aumento de 2.500x nos terços médio e apical, tendo sido utilizada a escala Rome (quantidade de túbulos dentinários abertos) por um pesquisador que não participou do estudo. Para a análise estatística aplicaram-se o teste de qui-quadrado e a prova exata de Fisher r. Na análise dos resultados foi possível observar que, de acordo com os valores obtidos das propriedades físico-químicas determinadas, a solução se mantém constante nos diferentes tempos de avaliação. De acordo com a comparação dos valores obtidos na avaliação das amostras no terço médio e apical baseados no sistema Rome, houve diferença estatística entre os grupos controle negativo (água destilada) e positivo (p<0,05 ­ exata de Fisher), assim como entre o grupo controle negativo (água destilada) e experimental [APO (p<0,05 ­ exata de Fisher)]. Não houve diferença estatística entre grupo controle positivo (NaOCl associado ao EDTA) e grupo experimental (APO). Conseguiu-se a obtenção eletrolítica da APO, que, de acordo com as propriedades físico-químicas determinadas, tem uma estabilidade de até 7 dias. Os resultados da análise sob microscopia permitiram observar que a APO atingiu 75% de túbulos dentinários permeáveis, e assim se demonstra que tal solução tem a capacidade de remover matéria orgânica e inorgânica. Sem dúvida, para poder propor o uso da APO como solução irrigadora em Endodontia é imperiosa a realização de estudos de citotoxicidade e biocompatibilidade

The purpose of the study was to elaborate the potentially oxidative water (POW) and analyze some of the physico-chemical properties: pH density, superficial stress, contact angle, conductivity and REDOX potential; besides comparing its POW organic as well as non-organic matter removal capacity with hypochlorite sodium at 1% plus 17% EDTA. For the methodology the POW elaboration an electrolysis process was used and the physico-chemical properties were determined in 0, 1, 3, 5 and 7 days. For the removal capacity of teeth tartar evaluation, 30 extracted uniradicular premolars were used, divided in three groups: positive control (NaOCl at 1% + EDTA at 17%), negative control (distilled water) and experimental (POW). Afterwards, the samples were observed under electronic microscopy with 2500x magnifying at the middle thirds and apical, analyzing them with the Rome scale (amount of open dental tubes). For the statistical analysis the Chi-square and the Fisher Exact Proof was used. The results showed that the solution was constantly maintained at all times during the evaluation and there was found statistical difference between negative control and positive control and between negative control and the experimental group. With regards to the dental tartar removal it was found that there was no statistical difference between the control group and the experimental group (POW); reason why it is concluded that the POW has the capacity to remove dental tartar. Nevertheless, to be able to propose the use of the POW as an irrigator solution in Endodontics it is necessary to do further studies to evaluate its cytotoxicity and biocompability