Susceptibilidad antimicrobiana de microorganismos anaerobios aislados de infecciones endodónticas primarias a amoxicilina y metronidazol y su asociación con los parámetros clínicos: serie de casos / Antimicrobial susceptibility of anaerobic microorganisms isolated from primary endodontic infections to amoxicillin and metronidazole and its association with clinical parameters: case series

El objetivo de este estudio es describir la composición de la microbiota anaerobia estricta/aerotolerante en infecciones endodónticas primarias, su susceptibilidad antimicrobiana, y la asociación con los parámetros clínicos. Se tomaron muestras de siete pacientes con necrosis pulpar sintomática o asintomática. Se utilizaron técnicas para la conservación, cultivo, incubación e identificación de anaerobios estrictos/aerotolerantes. Para determinar la susceptibilidad antimicrobiana a amoxicilina y metronidazol, se utilizó el método de dilución en agar. Se aislaron un total de 32 cepas, 20 (62,5 %) fueron anaerobios estrictos/aerotolerantes, y 8 (25 %) anaerobios facultativos. El microorganismo anaerobio estricto/aerotolerante más frecuente fue Fusobacterium nucleatum, se aisló en tres casos, todos relacionados con algún tipo de dolor, y en dos casos estuvo relacionado con Prevotella spp. Se encontró una colonia de F. nucleatum resistente a amoxicilina y con producción de ß-lactamasa, y otra de F. nucleatum resistente a metronidazol. Una colonia de P. propionicum/avidus presentó resistencia intermedia a amoxicilina y con producción de ß-lactamasa. Se encontró la presencia de bacterias anaerobias estrictas/aerotolerantes en los pacientes con infecciones endodónticas primarias. Existen algunos microrganismos relacionados con algún tipo de dolor, como F. nucleatum y P. micra. Los hallazgos muestran presencia de F. nucleatum resistentes a los antimicrobianos evaluados.

The objective of this study is to describe the composition of the strict / aerotolerant anaerobic microbiota in primary endodontic infections, antimicrobial susceptibility, and the association with clinical variables. Samples were taken from seven patients with symptomatic or asymptomatic pulp necrosis. conservation techniques, cultivation, incubation and identification of strict / aerotolerant anaerobes. We used the agar dilution method to determine the antimicrobial susceptibility to amoxicillin and metronidazole. A total of 32 strains, 20 (62.5 %) were isolated were strict / aerotolerant anaerobes, and 8 (25 %) facultative anaerobe organisms. The strict anaerobe / more Fusobacterium nucleatum was frequently aerotolerant, it was isolated in three cases, all related to some type of pain, and in two cases it was related to Prevotella spp. a colony of F. nucleatum resistant to amoxicillin and ß-lactamase production was found, and another F. nucleatum resistant to metronidazole. A colony of P. propionicum / avidus presented intermediate amoxicillin and ß-lactamase producing resistance. Conclusions: the presence of strict anaerobic bacteria / aerotolerant in patients with primary endodontic infections was found. There is some related pain, as F. nucleatum and P. micra microorganisms. The findings show the presence of F. nucleatum resistant to the antimicrobial organisms evaluated.

Effect of chlorhexidine, povidone iodine, and ozone on microorganisms in dental aerosols: Randomized double-blind clinical trial.

Objective: Dental handpieces, ultrasonic scalers, air polishers, air abrasion units produce the most visible aerosols. The objective of this study was to assess the effect of chlorhexidine (CHX), povidone iodine (PI), and ozone (OZ) on the microorganisms in dental aerosols. Materials and Methods: A total of 60 patients were included in this study, they were randomly assigned into three groups and were subjected to scaling before and after rinsing with 0.2% CHX, 1% PI or irrigation with OZ. Blood agar plates were used to collect the gravitometric settling of aerosols and were sent for aerobic and anaerobic culture. Results: The results demonstrated high percentage reduction of aerobic and anaerobic colony forming units (CFUs) in all three groups. In aerobic CFUs, CHX showed the highest reduction (57%) at mask position whereas at chest position and at 9 ft, PI showed higher CFU reductions (37% and 47%, respectively). In anaerobic CFUs, CHX showed the highest percentage of reduction at chest level (43%) and at 9 ft (44%). Conclusion: CHX, PI and OZ showed similar effects in reducing aerobic and anaerobic CFU's at the chest mask and at 9 ft. OZ can be used as a preprocedural agent, considering its beneficial effects.

Honeybee propolis extract in periodontal treatment: A clinical and microbiological study of propolis in periodontal treatment.

Objective: This study was conducted to evaluate by clinical and microbiological parameters the effect of subgingival irrigation with propolis extract. Materials and Methods: Twenty patients diagnosed with chronic periodontitis, each presenting three non-adjacent teeth with deep pockets, were selected. Subgingival plaque sampling and clinical recording (at baseline) and scaling and root planing was performed. Two weeks later the selected periodontal sites were submitted to one of the following treatments: Irrigation with a hydroalcoholic solution of propolis extract twice a week for 2 weeks (group A); irrigation with a placebo twice a week for 2 weeks (group B); or no additional treatment (group C). Clinical and microbiological data was collected at baseline and after 4, 6, and 8 weeks. Results: A decrease in the total viable counts of anaerobic bacteria (P=.007), an increase in the proportion of sites with low levels (≤10 5 cfu/mL) of Porphyromonas gingivalis (P=.044), and an increase in the number of sites negative for bleeding on probing was observed in group A sites as compared to group B and C sites. Conclusion: Subgingival irrigation with propolis extract as an adjuvant to periodontal treatment was more effective than scaling and root planing as assessed by clinical and microbiological parameters.

Antimicrobial resistance of aerobes and facultative anaerobes isolated from the oral cavity

OBJECTIVES: This study evaluated the resistance to antimicrobials of aerobes and facultative anaerobes isolated from patients wearing complete dentures, patients with gingivitis and periodontitis, and periodontally health subjects. MATERIAL AND METHODS: Three hundred and four isolates were tested. The minimal inhibitory concentrations of the drugs were evaluated through the agar dilution method using Mueller-Hinton agar. RESULTS: The most active antimicrobial drugs were the carbapenems (meropenem and imipenem), and resistance to these drugs was restrict to 1.6-2.3 percent of the isolates, as well as ciprofloxacin and rifampin. Microbial resistance to ampicillin, amoxicillin/clavulanic acid, cefoxitin, cephalothin, amikacin, chloramphenicol and nalidixic acid was particularly high. In most cases, the resistance to β-lactams was mediated by the production of hydrolytic enzymes, especially in gram-negative enteric rods, while enterococci did not evidence production of these enzymes. The association amoxicillin/clavulanic acid was not effective in 28.3 percent of the tested isolates. CONCLUSIONS: The results of this investigation confirmed that the oral cavity of patients with periodontitis and gingivitis, and particularly edentulous patients wearing complete dentures could harbor microorganisms with several antimicrobial resistance markers, and these microorganisms are frequently implicated in multiresistant, systemic, oral or nosocomial infections.

Photodynamic therapy - A strategic review.

Mechanical removal of the biofilm and adjunctive use of antibacterial disinfectants or various antibiotics have been conventional methods of the periodontitis therapy. There has been an upsurge of bacterial strains becoming resistant due to the injudicious use of antibiotics, recently. As a result there is pronounced interest and keenness in the development of alternate antimicrobial concepts. As the scientific community seeks alternatives to antibiotic treatment, periodontal researchers have found that photodynamic therapy (PDT) is advantageous to suppress anaerobic bacteria. Hence, PDT could be an alternative to conventional periodontal therapeutic methods. This review elucidates the evolution and use of photo dynamic therapy. The application of photosensitizing dyes and their excitation by visible light enables effective killing of periodontopathogens. Even though PDT is still in the experimental stages of development and testing, the method may be an adjunct to conventional antibacterial measures in periodontology. PDT application has an adjunctive benefit besides mechanical treatment at sites with difficult access. Necessity for flap operations may be reduced, patient comfort may increase and treatment time decrease. Clinical follow-up studies are needed to confirm the efficacy of the procedure.

Antimicrobial effect of MTAD, Tetraclean, Cloreximid, and sodium hypochlorite on three common endodontic pathogens.

Objectives: The aim of this in vitro study was to evaluate the antimicrobial action of BioPure MTAD (Dentsply Tulsa Dental, Johnson City, TN), Tetraclean, Cloreximid (a mixture of Chlorhexidine (CHX) digluconate and Cetrimide), and 5.25% NaOCl (Ogna Laboratori Farmaceutici, Milano, Italy) against selected endodontic pathogens (Enterococcus faecalis, Porphyromonas gingivalis, and Prevotella intermedia). Materials and Methods: The agar plate diffusion procedure was used to observe the antimibrobial activity of irrigants. Results: Statistical analysis revealed significant effects of the different irrigants on the bacteria colonies. Treatment with 5.25% NaOCl induced a larger zone of microbial inhibition in Prevotella intermedia and Porphyromonas gingivalis (Tukey HSD post-test, P = 0.0001) when compare to MTAD, Tetraclean and CHX. Anyway, MTAD and Tetraclean were more effective to inhibit bacterial growth compared to CHX (P < 0.0001, Tukey HSD post-test). Furthermore, post hoc analysis revealed that MTAD and Tetraclean induced the largest zone of microbial inhibition of Enterococcus faecalis cultured under both aerobic and anaerobic conditions, when compared with 2% CHX and NaOCl (P < 0.0001, Tukey HSD post-test). The control group showed no microbial inhibition. Conclusion: 5.25% NaOCl showed a high antimicrobial activity against anaerobic bacteria. MTAD and Tetraclean showed a high action against both, strictly anaerobic and facultative anaerobic bacteria. Chlorexidine + Cetrimide (Cloreximid) showed the lowest antibacterial activity against both, facultative and strictly anaerobic bacteria tested.

In vitro antimicrobial activity of endodontic pastes with propolis extracts and calcium hydroxide: a preliminary study

The purpose of this study was to evaluate the antimicrobial activity of two experimental pastes containing propolis extract associated with calcium hydroxide against polymicrobial cultures collected from 16 necrotic and fistulae root canals in primary molars of 4-8-year-old children of both sexes. The agar-well diffusion technique was used to determine the antimicrobial activity of the following pastes: 11.0 percent ethanolic extract of propolis (EEP) + calcium hydroxide; and 11.0 percent extract of propolis without ethanol (EP) + calcium hydroxide. EEP, EP and the association of calcium hydroxide and propylene glycol (CHP) was used as the positive control groups, and propylene glycol was used as a negative control group. Friedman and Wilcoxon tests were used to compare the data from the microbial growth inhibition zones (p<0.05). Paste 1 and Paste 2 showed larger growth inhibition zones against microorganisms from root canal samples than CHP (p=0.021 and 0.003, respectively). Paste 2 tended to have larger growth inhibition zones than Paste 1 (p=0.053). The association between propolis and calcium hydroxide was effective in controlling dental infections in vitro.

O objetivo dessa pesquisa foi avaliar a atividade antimicrobiana de duas pastas experimentais, contendo própolis associada a hidróxido de cálcio, contra culturas polimicrobianas coletadas de 16 molares decíduos necrosados e com fístulas extraídos de crianças entre 4 e 6 anos de idade de ambos os sexos. A técnica de difusão em ágar foi utilizada para determinar a atividade antimicrobiana das seguintes pastas: (1) 11,0 por cento extrato etanólico de própolis + hidróxido de cálcio e (2) 11,0 por cento extrato de própolis sem álcool + hidróxido de cálcio. A associação de hidróxido de cálcio com propilenoglicol foi utilizada como o grupo de controle positivo (CHP). Testes estatísticos de Friedman and Wilcoxon foram empregados para comparar dados do crescimento das zonas de inibição (p<0,05). Pasta 1 e Pasta 2 apresentaram zonas de inibição maiores contra os microrganismos coletados dos canais radiculares do que CHP (p=0,021 e 0,003 respectivamente). A Pasta 2 mostrou zonas de inibição um pouco mais largas que a Pasta 1 (p=0,053). A associação entre própolis e hidróxido de cálcio foi efetiva no controle de infecções dentárias in vitro.

Susceptibilidad in vitro de bacterias anaeróbicas en infecciones pleuropulmonares / In vitro antimicrobial susceptibility of anaerobic bacteria isolated from pleuropulmonary infections

Background: Aspirative pleuropulmonary infections are usually caused by anaerobic flora of the mouth, mainly Prevotella, Fusobacterium and Peptostreptococcus spp. Penicillin in high doses is the traditional treatment for this type of infections but the rising resistance developed in recent years has induced the empiric use of clindamycin, increasing treatment costs. Aim: To study antimicrobial susceptibility of anaerobic bacteria isolated from pleuropulmonary infections. Material and methods: Thirty two strains obtained from bronchoalveolar lavage and 15 strains isolated from pleural effusions between 2000 and 2002, were studied. The phenotype of strains was identified using the semiautomated API 20 A method and their susceptibility to penicillin (PNC), clindamycin (CM) and chloramphenicol (CAF) was tested using the E test methods. Results: All the strains were susceptible to CAF, 95% to CM and 74.4% to PNC. The predominant genus was Prevotella, which also exhibited the higher resistance. Conclusions: As CM and CAF are active "in vitro", high rates of clinical response should be expected. In contrast, PNC is less effective, especially against pigmented Prevotella.

Actividad “in vitro” de 10 antimicrobianos frente a bacterias anaerobias: Estudio multicéntrico, 1999-2002 / “In vitro” activity of ten antimicrobial agents against anaerobic bacteria. A collaborative study, 1999-2002

Se evaluó la actividad de ampicilina, ampicilina-sulbactama, cefoxitina, ceftriaxona, imipenem, piperacilina, piperacilina-tazobactama, clindamicina, metronidazol y azitromicina frente a 166 cepas de bacterias anaerobias aisladas en 8 hospitales de Buenos Aires. Se estudiaron: Bacteroides grupo fragilis (65), Fusobacterium spp. (26), Prevotella spp. (21), Porphyromonas spp. (10), Clostridium difficile (10), otros clostridios (12) y cocos gram-positivos (22). Las CIMs se determinaron usando el método patrón de dilución en agar recomendado por el NCCLS, documento M11-A5. Los antibióticos más activos fueron metronidazol y piperacilina-tazobactama que exhibieron valores de CIM90£ 2 µg/ml y £ 4 µg/ml frente a los microorganismos gram-negativos y £ 2 µg/ml y £ 8 µg/ml frente a los microorganismos gram-positivos, respectivamente. Entre los b-lactámicos el orden de actividad frente a bacilos gram-negativos fue: imipenem > piperacilina > cefoxitina > ceftriaxona > ampicilina. En gram-positivos la actividad decreciente fue: piperacilina> imipenem > cefoxitina > ceftriaxona > ampicilina. La mayoría de las especies estudiadas mostraron distintos niveles de resistencia con clindamicina y azitromicina. Sin embargo, el 90% de las cepas de Fusobacterium nucleatum y Por-phyromonas spp. fue inhibido por una concentración de 0,125 µg/ml de clindamicina y azitromicina, respectivamente.

The antimicrobial activity of ampicillin, ampicillin-sulbactam, cefoxitin, ceftriaxone, imipenem, piperacillin, piperacillin-tazobactam, clindamycin, metronidazole, and azitromycin was assesed against 166 strains of anaerobic bacteria recovered from eight hospitals in Buenos Aires. The strains studied were Bacteroidesfragilis group (65), Fusobacterium spp. (26), Prevotella spp. (21), Porphyromonas spp. (10), Clostridium difficile (10), other clostridia (12), and gram-positive cocci (22). The MICs were determined by the agar dilution method according to NCCLS document M11-A5. Metronidazole and piperacillin-tazobactam were the most active antimicrobial agents tested and exhibited MIC90values of £ 2 µg/ml and £ 4 µg/ml against gram-negative organisms, and £ 2 µg/ml, and £ 8 µg/ml against gram-positive organisms, respectively. Among b-lactams the activity against gram-negative rods was in the following order: imipenem> piperacillin > cefoxitin > ceftriaxone > ampicillin. Among the gram-positive bacteria the decreased activity was: piperacillin> imipenem> cefoxitin > ceftriaxone > ampicillin. The majority of the species studied showed different degrees of resistance to clindamycin and azitromycin. Nevertheless, 90% of Fusobacterium nucleatum and Porphyromonas spp. isolates were inhibited by 0.125 mg/ml of clindamycin and azitromycin, respectively.

Antibiotic susceptibility of bacterial isolates in gingivitis and periodontitis.

The present study was conducted to isolate aerobic as well as anaerobic microbes from patients of gingivitis and adult periodontitis and to study the susceptibility patterns of these isolates to different antibiotics. In our study all the samples belonging to the control as well as the study groups yielded microbes. Aerobes and facultative anaerobes were isolated from 100 percent and 96 percent cases of normal gingiva and orodental infections respectively. Anaerobes were isolated from 80 percent of the normal gingival samples and 97 percent of the cases of orodental infections. Metronidazole was found to be the best for the anaerobes while the aerobes and facultative anaerobes showed good susceptibility to cefazolin and cefotaxime.

Antimicrobial activity of different concentrations of NaOCl and chlorhexidine using a contact test

The purpose of this study was to analyze the in vitro antimicrobial activity of sodium hypochlorite (1 percent and 5 percent) and chlorhexidine (0.12 percent, 0.5 percent and 1 percent). Bacterial samples (ATCC) of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Porphyromonas gingivalis and Fusobacterium nucleatum were submitted to a contact test. Solutions were evaluated at different time intervals: immediately, 5 min, 15 min, and 30 min after contact and repeated 10 times. The results of the contact test showed that 0.12 percent chlorhexidine did not eliminate E. faecalis at any time interval, while 0.5 percent and 1 percent chlorhexidine and 1 percent and 5 percent sodium hypochlorite did. These results permit us to conclude that to obtain better antimicrobial activity, chlorhexidine in a concentration greater than 0.12 percent should be used

Study of fungal and bacterial infections of the diabetic foot.

Microbiological study for aerobic organisms, anaerobic organisms and fungi from 105 cases of diabetic foot ulcers was carried out to determine the aetiological agents and their antibiograms. Out of 265 microbial isolates obtained, 160 were aerobes, 50 anaerobes and 55 fungal strains. Polymicrobial infection was observed in 73 (69.5%) cases. The most frequently isolated aerobic microorganisms were Staphylococcus aureus and Pseudomonas aeruginosa. Among the anaerobes Bacteroides melaninogenicus and Bacteroides fragilis were most common. Candida species were preponderant among the fungal isolates. Antimicrobial sensitivity pattern of the isolates is discussed in detail.

Incidence of anaerobes in throat infections and their sensitivity pattern in Ludhiana.

Of 175 throat swabs processed, anaerobes were isolated from 16 (9.14%) patients. Isolation of anaerobes from healthy controls was 2 out of 25 (8%). Peptostreptococci and Bacteroides species were the commonest isolates followed by Peptococci and Propioni-bacterium. All of these isolates were sensitive to Metronidazole. Clindamycin, Erythromycin and Tetracycline also showed good response.

The medical management of diabetes mellitus with particular reference to the lower extremity: the Jamaican experience

Predisposing factors for the diabetic foot include peripheral neuropathy, peripheral vascular disease (PVD), hyperglycaemia and increased duration of diabetes. From the records of patients admitted to the University Hospital of the West Indies with the diabetic foot, we reviewed the results of the microbiology of wound swabs from diabetic foot ulcers. We noted the high prevalence of P VD (66.6), peripheral neuropathy (50), hyperglycaemia (75.6) and increased duration of diabetes (17.5 years). A history of past foot ulcers was common and 87.2had polymicrobial infection. The commonest organisms were gram positive organisms which were usually sensitive to the 2 antibiotic regimes that were commonly used. Euglycaemia, a favourable lipid profile, control of blood pressure, yearly foot examination and institution of measures to prevent foot trauma are important in the prevention of foot ulceration.

Efeitos de hidróxido de cálcio associado a diferentes veículos sobre dentina contaminada / Effects of calcium hydroxide associated with different vehicles on dentin contaminated

Cilindros de dentina bovina foram experimentalmente contaminados com uma cultura mista de Fusobacterium nucleatum e Prevotella intermedia, duas espécies bacterianas anaeróbicas estritas, comumente encontradas em infecçöes endodônticas. Estes espécimes foram expostos a quatro formulaçöes diferentes de pastas de hidróxido de cálcio (HC). Os espécimes foram deixados em contato com as pastas por 3 e 5 dias. Finalizados estes períodos a viabilidade bacteriana foi avaliada, através de incubaçäo dos espécimes em caldo de cultura, de forma a comparar a efetividade das pastas na descontaminaçäo da dentina. Apenas a pasta HPG foi capaz de, efetivamente, descontaminar a dentina após 5 dias de contato

Qué antibióticos prescribimos los dentistas? / Which antibiotics do dentists prescribe?

Las infecciones odontogénicas son comunes en la práctica del cirujano dentista, el tratamiento consiste en el establecimiento de un drenaje y en la eliminación de la fuente de infección que en ocasiones puede ser acompañado por la prescripción de antibióticos. Para conocer qué antibióticos prescriben los cirujanos dentistas, se circuló un cuestionario entre 303 dentistas de tres ciudades de la república mexicana. El antibiótico más prescripto fue la ampicilina (23 por ciento), seguido de la eritromicina (11 por ciento) y la penicilina V con un 10 por ciento. La duración del tratamiento también fue variable, siendo el esquema de 7 días (50.87 por ciento) el más frecuente, seguido de menos de 7 días (35.19 por ciento) y de más de 7 días, 13,93 por ciento. Actualmente sabemos que las infecciones odontogénicas son polimicrobianas, con un 65 por ciento de microorganismos anaerobios y que la ampicilina tiene poca actividad contra anaerobios. Los resultaods de la encuesta sugieren, de manera indirecta, que en la mayor parte de los dentistas entrevistados no existe el conocimiento adecuado del tipo de microorganismo invlucrado en las infecciones odontogénicas y de la sensibilidad y resistencia bacteriana a los antibióticos necesarios para poder prescribir antimicrobianos