scholarly journals In Vitro Alkaline pH Resistance of Enterococcus faecalis

2013 ◽  
Vol 24 (5) ◽  
pp. 474-476 ◽  
Author(s):  
Paulo Henrique Weckwerth ◽  
Ronald Ordinola Zapata ◽  
Rodrigo Ricci Vivan ◽  
Mário Tanomaru Filho ◽  
Amanda Garcia Alves Maliza ◽  
...  

Enterococcus faecalis is a bacterial species often found in root canals with failed endodontic treatment. Alkaline pastes are widely used in Endodontics because of their biocompatibility and antimicrobial activity, but this microorganism can resist alkalinity. The purpose of this study was to evaluate in vitro the alkaline pH resistance of E. faecalis for different periods up to 14 days. Samples were obtained from the oral cavity of 150 patients from the Endodontic clinic. The pH of the experimental tubes (n=84) was first adjusted with 6M NaOH to pH values of 9.5, 10.5, 11.5 and 12.5 (21 tubes per pH). Twenty clinical isolates and the ATCC 29212 strain were tested. The 5 positive controls and experimental tubes of each pH were inoculated with 10 µL of bacterial suspension and incubated at 36 °C for 24, 48 and 72 h, 7 and 14 days. For each period, the turbidity of the medium was visually compared with a 0.5 McFarland standard. The presence of the microorganism was confirmed by seeding on M-Enterococcus agar. Four tubes containing BHI broth adjusted to the tested pHs were incubated for 14 days to verify if pH changes occurred. The pH of inoculated BHI broth was also measured on day 14 to determine if the microorganism acidified the medium. The growth of all E. faecalis strains occurred at pH 9.5 to 11.5 in all periods. Although turbidity was not observed at pH 12.5, there was growth of 13 and 2 strains at 24 and 48 h, respectively, on M-Enterococcus agar. No tube showed growth at pH 12.5 after 72 h. It was concluded that E. faecalis can survive in highly alkaline pH, and some clinical isolates require 72 h at pH 12.5 to be killed.

2013 ◽  
Vol 21 (2) ◽  
pp. 118-123 ◽  
Author(s):  
Marcia Carneiro Valera ◽  
Lilian Eiko Maekawa ◽  
Luciane Dias de Oliveira ◽  
Antonio Olavo Cardoso Jorge ◽  
Erika Shygei ◽  
...  

2016 ◽  
Vol 17 (2) ◽  
pp. 114-118 ◽  
Author(s):  
Marcia C Valera ◽  
Sarah AC Oliveira ◽  
Lilian E Maekawa ◽  
Flávia GR Cardoso ◽  
Adriana Chung ◽  
...  

ABSTRACT Aim The purpose of this in vitro study was to evaluate the antimicrobial activity of 2% chlorhexidine gel (CHX) as auxiliary chemical substance and intracanal medications on Candida albicans, Candida albicans, Enterococcus faecalis, Escherichia coli, and their endotoxins in the root canals. Materials and methods The study was conducted on 48 single-rooted human teeth divided into four groups (n = 12), according to intracanal medications used: (1) Calcium hydroxide + apyrogenic saline solution (Ca(OH)2 + SS), (2) 20% ginger glycolic extract (GEN), (3) calcium hydroxide + 20% ginger glycolic extract (Ca(OH)2 + GEN), (4) apyrogenic SS (control). Collections were made from the root canal content before preparation (baseline–S1), immediately after instrumentation (S2), 7 days after instrumentation (S3), after 14 days the action of intracanal medication (S4), and 7 days after removal of the intracanal medication (S5). The antimicrobial activity and endotoxin content were analyzed for all collections. The results were statistically analyzed by the Kruskal–Wallis and Dunn tests at a significance level of 5%. Results After instrumentation with CHX, there was complete elimination of E. coli and C. albicans, except for E. faecalis, which was significantly reduced and then completely eliminated after intracanal medication. There was significant reduction of endotoxin after instrumentation. Comparison of collection after instrumentation and intracanal medication revealed reduction of endotoxins in all groups; this reduction was greater in group Ca(OH)2 followed by the group GEN. Conclusion It was concluded that the instrumentation using CHX and intracanal medication used were able to eliminate the microorganisms from the root canal; the endotoxins were reduced, yet not completely eliminated. Clinical significance This study is important and relevant for searching alternatives during endodontic therapy, since it aims to study the effect of Zingiber officinale on microorganisms and endotoxins present in root canals. How to cite this article Valera MC, Oliveira SAC, Maekawa LE, Cardoso FGR, Chung A, Silva SFP, Carvalho CAT. Action of Chlorhexidine, Zingiber officinale, and Calcium Hydroxide on Candida albicans, Candida albicans, Enterococcus faecalis, Escherichia coli, and Endotoxin in the Root Canals. J Contemp Dent Pract 2016; 17(2):114-118.


2021 ◽  
Vol 16 (Supp. 1) ◽  
pp. 11-15
Author(s):  
Aprilia Aprilia ◽  
Belinda Kusuma ◽  
Istien Wardani

The goal of endodontic treatment is to prevent and control of pulp and periradicular infections. Calcium hydroxide has a beneficial biological property as an intracanal medicament and can be combined with cresotin to disinfect bacteria in root canals, especially Enterococcus faecalis (E. faecalis) which is the most frequently isolated strain in the root canals. The aim of this study was to investigate in vitro the antimicrobial activity of calcium hydroxide, cresotin, and combination calcium hydroxide and cresotin (Ca[OH]2+Cresotin, 1:1 and 1:2) against E. faecalis. Antibacterial activity was determined by the agar diffusion method. The test medicaments were placed inside the hole that made in the inoculated agar medium. The zone of growth inhibition was measured and recorded after incubation for each plate, and the result was analysed statistically with ANOVA. The in vitro antimicrobial effects of combination calcium hydroxide and cresotin (Ca[OH]2+Cresotin, 1:2) has more prominent antimicrobial activity than others, and calcium hydroxide is more effective than cresotin alone. The antimicrobial activity of combined calcium hydroxide and cresotin is more effective in killing E. faecalis in comparison to the other treatments.


2021 ◽  
Vol 9 (3) ◽  
pp. 517
Author(s):  
Mohamed El-Telbany ◽  
Gamal El-Didamony ◽  
Ahmed Askora ◽  
Eman Ariny ◽  
Dalia Abdallah ◽  
...  

Phage therapy is an alternative treatment to antibiotics that can overcome multi-drug resistant bacteria. In this study, we aimed to isolate and characterize lytic bacteriophages targeted against Enterococcus faecalis isolated from root canal infections obtained from clinics at the Faculty of Dentistry, Ismalia, Egypt. Bacteriophage, vB_ZEFP, was isolated from concentrated wastewater collected from hospital sewage. Morphological and genomic analysis revealed that the phage belongs to the Podoviridae family with a linear double-stranded DNA genome, consisting of 18,454, with a G + C content of 32.8%. Host range analysis revealed the phage could infect 10 of 13 E. faecalis isolates exhibiting a range of antibiotic resistances recovered from infected root canals with efficiency of plating values above 0.5. One-step growth curves of this phage showed that it has a burst size of 110 PFU per infected cell, with a latent period of 10 min. The lytic activity of this phage against E. faecalis biofilms showed that the phage was able to control the growth of E. faecalis in vitro. Phage vB_ZEFP could also prevent ex-vivo E. faecalis root canal infection. These results suggest that phage vB_ZEFP has potential for application in phage therapy and specifically in the prevention of infection after root canal treatment.


1948 ◽  
Vol 88 (1) ◽  
pp. 99-131 ◽  
Author(s):  
Harry Eagle ◽  
A. D. Musselman

1. The concentrations of penicillin G which (a) reduced the net rate of multiplication, (b) exerted a net bactericidal effect, and (c) killed the organisms at a maximal rate, have been defined for a total of 41 strains of α- and ß-hemolytic streptococci, Staphylococcus aureus and Staphylococcus albus, Diplococcus pneumoniae, and the Reiter treponoma. 2. The concentration which killed the organisms at a maximal rate was 2 to 20 times the minimal effective level ("sensitivity" as ordinarily defined). With some organisms, even a 32,000-fold increase beyond this maximally effective level did not further increase the rate of its bactericidal effect. However, with approximately half the strains here studied (all 4 strains of group B ß-hemolytic streptococci, 4 of 5 group C strains, 5 of 7 strains of Streptococcus fecalis, 2 of 4 other α-hemolytic streptococci, and 4 of 9 strains of staphylococci), when the concentration of penicillin was increased beyond that optimal level, the rate at which the organisms died was paradoxically reduced rather than increased, so that the maximal effect was obtained only within a relatively narrow optimal zone. 3. There were marked differences between bacterial species, and occasionally between different strains of the same species, not only with respect to the effective concentrations of penicillin, but also with respect to the maximal rate at which they could be killed by the drug in any concentration. Although there was a rough correlation between these two factors, there were many exceptions; individual strains affected only by high concentrations of penicillin might nevertheless be killed rapidly, while strains sensitive to minute concentrations might be killed only slowly. 4. Within the same bacterial suspension, individual organisms varied only to a minor degree with respect to the effective concentrations of penicillin. They varied strikingly, however, in their resistance to penicillin as measured by the times required to kill varying proportions of the cells.


2007 ◽  
Vol 21 (4) ◽  
pp. 308-313 ◽  
Author(s):  
Eduardo Diogo Gurgel-Filho ◽  
Nilton Vivacqua-Gomes ◽  
Brenda Paula Figueiredo de Almeida Gomes ◽  
Caio Cezar Randi Ferraz ◽  
Alexandre Augusto Zaia ◽  
...  

The purpose was to assess the elimination of Enterococcus faecalis in vitro in human mandibular premolars after chemomechanical preparation with or without the use of a calcium hydroxide dressing. After 60 days of contamination with E. faecalis, the root canals were prepared using the Crown-Down technique combined with 2% chlorhexidine gel irrigation. Then, the specimens were divided into two experimental groups, treated in a single visit or in multiple visits, and two control groups. The multiple-visit group received a dressing with calcium hydroxide for 14 days (CalenTM) and the single-visit group did not receive any medication. In the two control groups, the canals were filled with BHI after chemomechanical preparation with 2% chlorhexidine gel or distilled water. Microbial samples were taken from the root canals for colony forming unit count for each phase of the treatment using sterile paper points inside the root canal lumen. Data were ranked and analyzed by the Kruskal-Wallis statistical test. The residual microbial colonies were then assessed. The results showed that chemomechanical preparation using 2% chlorhexidine gel with no intra-canal dressing reduced by 100% the E. faecalis contamination of the root canal lumen. The calcium-hydroxide group that received the 14-day intra-canal dressing allowed a small number of bacteria to grow between visits, but without statistical differences between groups.


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