Continuous Drip Flow System to Develop Biofilm of E. faecalis

Purpose. To evaluate a structurally mature E. faecalis biofilm developed under anaerobic/dynamic conditions in an in vitro system. Methods. An experimental device was developed using a continuous drip flow system designed to develop biofilm under anaerobic conditions. The inoculum was replaced every 24 hours with a fresh growth medium for up to 10 days to feed the system. Gram staining was done every 24 hours to control the microorganism purity. Biofilms developed under the system were evaluated under the scanning electron microscope (SEM). Results. SEM micrographs demonstrated mushroom-shaped structures, corresponding to a mature E. faecalis biofilm. In the mature biofilm bacterial cells are totally encased in a polymeric extracellular matrix. Conclusions. The proposed in vitro system model provides an additional useful tool to study the biofilm concept in endodontic microbiology, allowing for a better understanding of persistent root canal infections

Apical Negative Pressure irrigation presents tissue compatibility in immature teeth

Aim: To compare the apical negative pressure irrigation (ANP) with conventional irrigation in the teeth of immature dogs with apical periodontitis. Methods: Fifty-two immature pre-molar root canals were randomly assigned into 4 groups: ANP (n=15); conventional irrigation (n=17); healthy teeth (control) (n = 10); and teeth with untreated apical periodontitis (control) (n=10). After induction of apical periodontitis, teeth were instrumented using EndoVac® (apical negative pressure irrigation) or conventional irrigation. The animals were euthanized after 90 days. The sections were stained by HE and analyzed under conventional and fluorescence microscopy. TRAP histoenzymology was also performed. Statistical analyses were performed with the significance level set at 5%. Results: There was difference in the histopathological parameters between ANP and conventional groups (p;0.05). However, a lower number of osteoclasts was observed in the ANP group (

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. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e42-e46

Influence of endodontic treatment and corona! restoration on status of periapical tissues: a cone-beam computed tomographic study

Introduction: This cross-sectional study determined the prevalence of apical radiolucency in 1290 root canal treated teeth and the correlation between endodontic treatment quality and the presence of coronal restorations with apical radiolucency using cone-beam computed tomographic imaging. Methods: Cone-beam, computed tomographic scans were analyzed, and teeth were classified as healthy or diseased according to the periapical status. Other factors were also evaluated for their association with the apical diagnosis including sex, quality of endodontic treatment, presence of corona] restorations and posts, and apical level of filling. Results: Of the treated teeth, 48.83% were classified as healthy. Only 55.11% of the teeth had endodontic treatment rated as adequate. The quality of endodontic treatment and the presence of coronal restoration were statistically correlated with the presence or absence of an apical radiolucency (P < .0001). Combined data revealed that teeth with both adequate endodontic treatment and the presence of coronal restoration showed significantly better apical status than the other combinations (P < .001). Canals filled up to 0-2 mm short of the apex had a significantly higher number of teeth rated as healthy compared with overfilled or underfilled cases (P = .001). The presence of a post was not found to be a statistical significant factor (P = .81). Conclusions: Data showed a relatively high prevalence of apical radiolucencies in root canal treated teeth. The quality of the endodontic treatment, the presence of corona] restoration, and apical extent of the root canal filling were significantly associated with healthy apical tissues.This cross-sectional study determined the prevalence of apical radiolucency in 1290 root canal treated teeth and the correlation between endodontic treatment quality and the presence of coronal restorations with apical radiolucency using cone-beam compute411016141618FAPERJ - FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIROE-26/201.491/201

Archivists and historians–Am I giving archivists too much credit?

Une discussion très intéressante sur le blog américain Archivesnext portant sur la collaboration entre archivistes et historiens, partie de pistes de réflexion de la blogueuse K. Theimer sur l'ouvrage Processing the Past: Contesting Authority in History and the Archives (Francis X. Blouin et William G. Rosenberg, Oxford University Press, 2011). C'est ici 

Evaluation of root canal configuration of maxillary and mandibular anterior teeth using cone beam computed tomography: an in-vivo study

Several studies demonstrate variability of root canal morphology of anterior teeth. This in-vivo study was designed to analyze and characterize root canal morphology of maxillary and mandibular anterior teeth using three-dimensional imaging. Method and Materials: Patients who required CBCT radiographic examinations as part of their routine examination, diagnosis, and treatment planning were enrolled on the study. A total of 1,200 healthy, untreated, fully developed maxillary and mandibular incisors and canines were included. The following observations were recorded: (i) number of roots and their morphology; (ii) number of canals per root; and (iii) primary variations in the morphology of the root canal systems. Results: Root canal morphology of maxillary teeth was consistent with a single canal extending from the pulp chamber to the apex in 98% of the cases. In contrast, in mandibular central and lateral incisors, the presence of a single canal represented 64.5% and 60.5% respectively. The second most common morphology was the presence of one canal leaving the pulp chamber, which divided into two within the root, and then merged to exit as one canal in 18% and 25.5% respectively. The presence of one canal leaving the pulp chamber and dividing short of the apex into two separate and distinct canals with separate apical foramina (variant 5) was recorded in 14.5% and 12% respectively. Conclusion: There was a low incidence of anatomical variation in maxillary anterior teeth. In contrast, mandibular anterior teeth presented with a high prevalence of two canals, especially central and lateral incisors. The reported data may help clinicians understand the variations in root canal morphology of anterior teeth in order to overcome problems associated with shaping and cleaning procedures.Several studies demonstrate variability of root canal morphology of anterior teeth. This in-vivo study was designed to analyze and characterize root canal morphology of maxillary and mandibular anterior teeth using three-dimensional imaging. Patients who4711924sem informaçãosem informaçã