Obtención de proteínas de membrana externa de bacterias periodontopatógenas y análisis de la respuesta inmunitaria de pacientes con periodontitis

Introducción: Las enfermedades periodontales son el resultado de la acumulación de microorganismos alrededor del diente y de la respuesta inmunitaria asociada. Las alteraciones provocadas por los mecanismos de defensa, en un intento de frenar el avance bacteriano, conducen a la pérdida de los tejidos de soporte. El cambio a una microbiota más patogénica, gram-negativa anaeróbica, dominada por microorganismos periodontopatógenos, puede marcar el inicio de la pérdida de inserción. Objetivo: El propósito de este estudio ha sido comparar la respuesta inmunitaria de pacientes con periodontitis e individuos sanos frente a proteínas de membrana externa de las cepas A. actinomycetemcomitans DSMZ8324, F. nucleatum DSM20482, P. gingivalis ATCC33277 y P. gingivalis W83. Material y Métodos: Los cultivos de células planctónicas se obtuvieron con una suspensión bacteriana de 107 unidades formadoras de colonia (UFC)/mL en medio Brain Heart Infusion (BHI) modificado tras 24 horas de incubación. Después se procedió a la extracción de las proteínas bacterianas y a su cuantificación por el método Bradford. Posteriormente, se obtuvo el perfil proteico mediante electroforesis en geles de poliacrilamida, y se identificaron por espectrometría de masas. La respuesta de anticuerpos presentes en los sueros de los pacientes frente a las bacterias se estudió mediante la técnica de Western-blot. Resultados: La mayoría de las proteínas identificadas han mostrado ser de membrana externa. El estudio de los sueros de los distintos individuos mostró una respuesta variable de anticuerpos frente a las proteínas de las bacterias estudiadas, siendo de forma general mayor en los pacientes con periodontitis. Conclusiones: La optimización de un protocolo de extracción para el enriquecimiento en proteínas bacterianas de membrana externa ha quedado evidenciado. La respuesta inmunitaria de pacientes con periodontitis e individuos sanos frente a proteínas de membrana externa de A. actinomycetemcomitans, F. nucleatum y P. gingivalis ha sido variable y diferente entre los pacientes, no dependiendo siempre de la carga bacteriana que presenta el individuo

Antimicrobial Activity and Cytotoxicity of Nonsteroidal Anti-Inflammatory Drugs against Endodontic Biofilms

Persistent infections have become a challenge in dentistry because of growing antibiotic resistance. Nonsteroidal anti-inflammatory drugs (NSAIDs) appear to be a therapeutic alternative to control biofilm infection. The objective of this work is to evaluate the antimicrobial activity and cytotoxicity of sodium diclofenac (DCS), ibuprofen (IBP) and ibuprofen arginine (IBP-arginine) solutions against endodontic polymicrobial biofilms. Sterile radicular dentin blocks of 4 mm 4 mm 0.7 mm were used as substrate to grow biofilm. The dentin blocks were submerged into solutions for 5 min. The antimicrobial activity was evaluated by means of the adenosine triphosphate (ATP) assay and confocal laser scanning microscopy (CLSM). Fibroblasts 3T3-L1 (ECACC 86052701) were used to test the cytotoxicity of irrigating solutions. The antibiofilm effects determined by the ATP assay showed that 4% IBP-arginine solution exerted the highest antibiofilm activity, followed by 4% DCS and 4% IBP, with statistical differences among groups (p < 0.001). As for CLSM, 4% DCS and 4% IBP-arginine solutions gave the lowest viable cell percentages, without significant differences between them. Cytotoxicity results at 1/10 dilution were similar for all solutions. At 1/100 dilution, a 4% DCS solution obtained the lowest cell viability for both time periods assayed, 1 h and 24 h. The IBP-arginine group showed the highest cell viability at 24 h. In this preliminary study, in terms of antibiofilm activity and cytotoxicity, a mixed 4% IBP-arginine solution gave the most promising results. NSAID solutions could be recommendable drugs for endodontic disinfection proceduresResearch Group CTS-167 of Junta de Andalucía, Spain

Antibiofilm Activity of Diclofenac and Antibiotic Solutions in Endodontic Therapy

Introduction: The aim of this study was to compare the antibiofilm effects of a triple antibiotic solution (TAS); a double antibiotic solution (DAS); and 5%, 2.5%, and 1.25% diclofenac solutions (DCSs) against Enteroccocus faecalis biofilm. Methods: Eighty-four sterile radicular dentin blocks were used as biofilm substrate for 3 weeks. The study groups were as follows: (1) 1 mg/mL TAS (minocycline, metronidazole, and ciprofloxacin), (2) 1 mg/mL DAS (metronidazole and ciprofloxacin), (3) 5% DCS, (4) 2.5% DCS, (5) 1.25% DCS, and (6) 0.9% saline solution. The antimicrobial activity was evaluated by bacterial count determinations and confocal laser scanning microscopy. The contact time for the antimicrobial tests was 5 minutes. Bacterial counts were expressed as the reduction percentage of colony-forming units; for the confocal laser scanning microscopic evaluation, the log10 total biovolume and percentage of green population (live cells) were calculated. Results: The colony-forming unit reduction percentage ranged between 62.98 and 98.62, respectively, for TAS and 5% DCS. The DCS showed a concentration-dependent effect.For the confocal laser scanning microscopy, the log10 total biovolume in all groups was very similar and showed a scarce (1.39-1.02) but significant reduction with respect to the control; 5% and 2.5% DCSs gave the lowest viable cell percentage. The TAS and DAS groups showed intermediate values without significant differences between them. Conclusions: DCSs at 5% and 2.5% have greater antimicrobial effects than TAS and DAS and may be considered a valid alternative for controlling the infection of teeth with apical periodontitis.Grupo CTS 16

Eficacia antibacteriana y biocompatibilidad de soluciones irrigadoras en Endodoncia

Hubo una correlación positiva entre ULRs y log10 (UFCs + 1)/ml. En los grupos en los que estaba presente el NaClO no hubo crecimiento bacteriano (UFCs). La menor eficacia antimicrobiana la mostraron los grupos EDTANa4. Hubo una reducción de ULRs similar en todos los grupos de estudio que contenían NaClO. En relación a la citoxicidad, para ambos tiempos, la solución de NaClO al 2,5% obtuvo la viabilidad celular más baja. La asociación de NaClO con EDTANa4 aumentó la viabilidad celular en relación directa a la concentración del agente quelante. Globalmente, después de 24 horas, la viabilidad celular se redujo en todos los grupos de estudio.There was correlation between RLUs and log10 (CFUs + 1)/ml. In the NaOCl groups there was no bacterial growth (CFUs). The lowest antimicrobial efficacy was found for the EDTANa4 groups. A similar reduction of RLUs in all NaOCl groups was seen. Regarding to cytotoxicity, the lowest viability was obtaines with a 2,5% NaOCl solution at both time periods. The association of NaOCl with EDTANa4 increased the celullar viability in direct relation with the concentration of the cheating agent. Globally, after 24 hours of exposure, cell viability reduced in all study groups.Tesis Univ. Granada

Root Canal Disinfection Articles with the Highest Relative Citation Ratios. A Bibliometric Analysis from 1990 to 2019

The relative citation rate (RCR) is a normalized article-level metric useful to assess the impact of research articles. The objective of this bibliometric study is to identify and analyze, in root canal disinfection, the 100 articles having the highest RCRs in the period 1990–2019, then compare them with the top 100 articles most cited. A cross-sectional study was performed, and the search strategy ((Disinfection AND root canal) AND ((“1990/01/01”[Date-Publication]: “2019/12/31”[DatePublication]))) relied on PubMed (n = 4294 documents), and article data were downloaded from the iCite database. The 100 articles with the highest RCRs and the top 100 cited were selected and evaluated in bibliometric terms. Among the 100 articles with the highest RCRs, there were no differences in the three decades for RCRs values, but there were in citations, being 2000–2009 the most cited. The USA was the predominant country (n = 30), followed by Brazil (n = 14). The most frequent study designs were reviews (n = 27) and in vitro (n = 25) and ex vivo (n = 24) studies. All subfields were well represented, although they varied over time. In 2010–2019, regenerative procedures and irrigation/disinfection techniques were predominant. Considering the RCR’s top 100 articles, 76 were common with the 100 most cited articles. Using the RCR metric allowed us to identify influential articles in root canal disinfection, a research field with topics of significance that fluctuate over time. Compared to citations, RCR reduces the time from publication to detection of its importance for the readership and could be a valid alternative to citation counts.Research Groups CTS-167 and HUM-777 of Junta de Andalucía, Spai

The highest relative citation ratios versus top cited articles. A bibliometric analysis in root canal disinfection

3 databases associated to paper 'The highest relative citation ratios versus top cited articles. A bibliometric analysis in root canal disinfection

Antimicrobial activity and cytotoxicity of nonsteroidal anti-inflamatory drugs against endodontic biofilms

Tres bases de datos de donde se obtienen los resultados de un artículo de investigació

Cytotoxic effects of alkaline tetrasodium EDTA irrigating solutions

The aim of this study is to determine the cytotoxic effects of tetrasodium ethylenediaminetetraacetic acid (EDTANa4) when used alone or when combined with sodium hypochlorite (NaOCl), with and without the addition of cetrimide (CTR). Human pulmonary fibroblast cell line was exposed to the following irrigating solutions: group 1, 2.5% NaOCl; group 2, 10% EDTANa4; group 3, 20% EDTANa4; group 4, 2.5% NaOCl/5% EDTANa4; group 5, 2.5% NaOCl/10% EDTANa4; group 6, 2.5% NaOCl/5% EDTANa4/0.2% CTR; group 7, 2.5% NaOCl/10% EDTANa4/0.2% CTR; group 8, control, cells in Dulbecco’s modified Eagle’s medium. Methyl thiazol tetrazolium assay was used to determine the viability of cells after 1 and 24 h. Viability percentages were analyzed for global comparison using the Welch test followed by the Games-Howell test to determine groups with similar viability, and the Student’s t test was used to compare the two times. The lowest viability was obtained with a 2.5% NaOCl solution at both time periods. The association of NaOCl with EDTANa4 increased the cellular viability in direct relation with the concentration of the chelating agent. Globally, after 24 h of exposure, cell viability reduced. The solutions of EDTANa4 showed moderate cytotoxic effects when compared with NaOCl alone.Junta de Andalucía CTS-16

Cetrimide increases diclofenac´s activity against polymicrobial root canal biofilm

Dos bases de datos de donde se obtienen los resultados de un artículo de investigació

Effectiveness of conservative instrumentation in root canal disinfection

Bases de datos utilizadas en un trabajo de investigación6 bases de datos en SPS