Genetic-relatedness of peri-implants and buccal Candida albicans isolates determined by RAPD-PCR.

Molecular techniques have been used in recent studies to identify a wide range of potential bacterial pathogens in periimplant pockets of the oral cavity. However, the prevalence and molecular epidemiology of yeasts and species distribution related to periimplantitis are as yet unknown. The aim of this study was to determine the prevalence and distribution of yeasts in periimplant biofilm and to study genetic relatedness of Candida albicans. Yeasts recovered from periimplant biofilm samples (n=89) and buccal samples (n=120) were studied in 40 immunocompetent nonsmoking patients who visited the dental clinic of the Asociación Implantodontológica Argentina, Buenos Aires, Argentina, and had received oral rehabilitation with implants for more than five years. Yeasts recovered from samples were studied by typing assays using RAPDPCR. The prevalence of yeasts in the periimplant sulcus was 73% (n=29). C. albicans was the most prevalent species identified in this study population. The RAPD analysis showed identical genotypes in most C. albicans spp. from the two different sampling sites: buccal and periimplant. These findings suggest that periimplant biofilm is an ecological niche that favors the growth of yeast species. Most C. albicans found in periimplant biofilm originate from the endogenous infection caused by commensal strains.

Las técnicas moleculares se han utilizado en estudios recientes para identificar una gran diversidad de patógenos bacterianos de surcos periimplantarios de cavidad bucal. Sin embargo, la prevalencia y epidemiología molecular de especies de levaduras en relación con la periimplantitis son aún desconocidas. El objetivo de este estudio fue determinar la prevalencia y distribución de las levaduras en la biopelícula periimplantaria y estudiar la relación genética de Candida albicans. Se estudiaron 40 pacientes inmunocompetentes no fumadores que se asistieron en la clínica dental de la Asociación Implantodontológica Argentina, Buenos Aires, Argentina, y que habían recibido rehabilitación oral con implantes durante más de cinco años. Las levaduras aisladas de las muestras de biopelícula periimplantaria (n = 89) y bucales (n = 120), fueron identificadas por métodos micológicos tradicionales y moleculares. Se obtuvo el ADN de C. albicans y se realizaron estudios moleculares por RAPD PCR. La prevalencia de levaduras en el surco alrededor del implante fue de 73 % (n = 29). C. albicans fue la especie más frecuente identificada en esta población de estudio. El análisis RAPD permitió identificar idénticos genotipos de C. albicans en ambos nichos ecológicos estudiados, periimplantar y bucal. Según los resultados obtenidos, el surco periiplantario es un nicho ecológico que favorece el crecimiento de especies de levaduras del género Candida. La mayoría de los aislamientos de C. albicans periimplantarios se originan a partir de la infección endógena causada por cepas comensales.

Gingival response in orthodontic patients: Comparative study between self-ligating and conventional brackets.

Orthodontic brackets contribute to the accumulation of bacterial plaque on tooth surfaces because they hinder oral hygiene. In contrast to conventional brackets, self-ligating brackets do not require additional parts to support the arches, thus improving dental hygiene. The aim of this study was to compare the gingival response in orthodontic patients wearing self-ligating or conventional brackets. A sample of 22 patients aged 16 to 30 years was divided into two groups: Group A, treated with selfligating brackets (Damon system) and Group B, treated with conventional brackets (Roth technique). The following were assessed during the treatment: Plaque Index (PI), Gingival Index (GI) and Probing Depth (PD), and sub-gingival samples were taken from teeth 14/24 for microbiological observation. No statistically significant difference was found between Groups A and B; p>0.05 (sign-ranked) or between PI, GI and PD at the different times (Friedman's Analysis of Variance), even though the indices were found to increase at 14 days, particularly for self-ligating brackets. The quantity and quality of microorganisms present were compatible with health on days 0, 28 and 56. As from day 14 there is a predominance of microbiota compatible with gingivitis in both groups. In the samples studied, orthodontic treatment increases bacterial plaque and inflammatory gingival response, but gingival-periodontal health can be maintained with adequate basic therapy. Self-ligating and conventional brackets produced similar gingival response.

Gingival response in orthodontic patients: Comparative study between self-ligating and conventional brackets. / Gingival response in orthodontic patients: Comparative study between self-ligating and conventional brackets.

Orthodontic brackets contribute to the accumulation of bacterial plaque on tooth surfaces because they hinder oral hygiene. In contrast to conventional brackets, self-ligating brackets do not require additional parts to support the arches, thus improving dental hygiene. The aim of this study was to compare the gingival response in orthodontic patients wearing self-ligating or conventional brackets. A sample of 22 patients aged 16 to 30 years was divided into two groups: Group A, treated with selfligating brackets (Damon system) and Group B, treated with conventional brackets (Roth technique). The following were assessed during the treatment: Plaque Index (PI), Gingival Index (GI) and Probing Depth (PD), and sub-gingival samples were taken from teeth 14/24 for microbiological observation. No statistically significant difference was found between Groups A and B; p>0.05 (sign-ranked) or between PI, GI and PD at the different times (Friedmans Analysis of Variance), even though the indices were found to increase at 14 days, particularly for self-ligating brackets. The quantity and quality of microorganisms present were compatible with health on days 0, 28 and 56. As from day 14 there is a predominance of microbiota compatible with gingivitis in both groups. In the samples studied, orthodontic treatment increases bacterial plaque and inflammatory gingival response, but gingival-periodontal health can be maintained with adequate basic therapy. Self-ligating and conventional brackets produced similar gingival response.

Nasal carriage of Staphylococcus aureus and Candida species in immunocompetent individuals.

The aim of this study was to analyze the prevalence of Staphylococcus aureus and Candida species in samples of nasal mucosa from 100 immunocompetent subjects of both sexes, aged 18-70 years, during stomatological clinical examination. Samples were taken from the mucosa of both nasal fossae using sterile swabs. Samples were observed fresh, stained with Gram and Giemsa, and cultured on selective differential media at 37 degrees C to isolate and identify the selected microorganisms; conventional biochemical tests and commercial equipment and molecular studies using PCR were performed. A digital thermometer-hygrometer was used to measure room temperature at the time of sampling, which was on average 25 +/- 2 degrees C, with relative ambient humidity 66 +/- 11%. S. aureus was isolated from 38% of the samples; 4% of the samples were methicillin-resistant (MRSA) strains, with 2% identified genetically as community-acquired (CA-MRSA) and 2% as hospital-acquired (HA-MRSA). Candida was identified in 23% of the samples, with prevalence of C. albicans (19%) followed by C. dubliniensis (3%) and C. krusei (1%). There was significant association between Candida and S. aureus (Chi-squared = 27.75; df = 1; (p < 0.001). The nasal cavity is a reservoir and the identification of genus and species contributes to adequate epidemiological surveillance.

Prevalence of Candida species in necrotic pulp with chronic periapical processes.

The aim of this study was to identify species of the genus Candida in mucosa of oral cavity and in single-rooted teeth with pulp necrosis with chronic endodontic periapical processes, with radiographic images 2+/-4 mm and without clinical symptomatology, in immunocompetent patients. The study included 82 immunocompetent patients of both sexes aged 18-70 years with a clinical dental diagnosis of septic pulp necrosis. Samples were taken from root canals with sterile # 25 paper points and from oral mucosa with a sterile swab. Seven different Candida species were identified (C. albicans, C. dubliniensis, C. guilliermondii, C. krusei, C. parapsilopsis, C. tropicalis and C. glabrata). All of them were present in oral mucosa, while two of them (C. parapsilopsis and C. glabrata) were not identified in the periapical zone of necrotic canals. Considering all the samples isolated from oral mucosa, there was a significantly greater frequency of C. albicans than there was in the periapical zone of necrotic canals.

Antibiotic susceptibility of Staphylococcus aureus isolates in oral mucosa and pockets of patients with gingivitis-periodontitis.

Both oral cavity and subgingival pocket are ecological niches conducive to hosting microorganisms that may act as opportunistic pathogens, such as Staphylococcus aureus and especially methicillin-resistant Staphylococcus aureus (MRSA). Early detection of MRSA is a matter of concern to Public Health. The aim of our study was to determine phenotypic and genotypic detection of methicillin resistance of S. aureus in oral mucosa and subgingival pocket in 102 patients with gingivitis-periodontitis. The prevalence of S. aureus was 10.8% (n = 11) in subgingival pocket and 19.6% (n = 20) in oral mucosa. We obtained 31 isolates of S. aureus of which 13 were mecA positive and 18 were mecA negative. Detection of mecA gene by PCR was used as the reference method to compare the results of phenotypic methods to determine methicillin resistance. Early, accurate detection of S. aureus through phenotyping and genotyping methods is crucial for assessing the colonization and preventing the spread of MRSA.

Prevalence of Staphylococcus spp and Candida spp in the oral cavity and periodontal pockets of periodontal disease patients.

The oral cavity can act as a reservoir of certain pathogens that can cause systemic infections. The periodontal pocket is an ecological niche appropriate for hosting microorganisms that could act as opportunistic pathogens. The ability of Staphylococcus spp and Candida spp to form a biofilm and live within certain niches allows them to develop mechanisms that increase persistence, such as the evasion of host defenses and antibiotic efficacy. These microorganisms can easily be or become resistant to antibiotics and lead to superinfection. The aims of this study were to assess the presence of Staphylococcus aureus and Staphylococcus spp in biofilm in subgingival plaque and oral cavity of individuals with gingival-periodontal disease, to identify isolates and the relationship with Candida spp. The study included eighty-two patients, aged 18-70 years with periodontal disease and at least two sites with probing depth > or = 3 mm. Participants' data were evaluated individually. Subgingival biofilm samples were obtained using Gracey curettes 7/8, after supragingival biofilm removal, and a sample from the oral cavity (buccal mucosa, tongue and cheek mucosa) by sterile swab. Of all the patients studied, 42.7% exhibited Staphylococcus spp in the periodontal pocket and 69.5% in the oral cavity while 25.6% exhibited Candida spp in the periodontal pocket and 42.7% in the oral cavity. However, 13.4% had both microorganisms in the periodontal pocket and 36.6% in the oral cavity. The prevalence of Staphylococcus aureus was 13.4% in the periodontal pocket and 15.8% in the oral cavity. Candida albicans was the most prevalent yeast in the periodontal pocket (76.2%) and in the oral cavity (63.0%).

The impact of oral contraceptives on women's periodontal health and the subgingival occurrence of aggressive periodontopathogens and Candida species.

BACKGROUND: The purpose of this study is to evaluate the influence of oral contraceptive (OC) use on the subgingival occurrence of specific periodontopathogens and the host's periodontal status. METHODS: Ninety-two females aged 19 to 40 years were included in the study. They were divided into two groups, OC users and non-users, and subgrouped according to the most severe periodontal condition and duration of OC usage. A pooled subgingival sample from each subject was cultured to investigate the presence of Candida species, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), and Prevotella intermedia. RESULTS: OC users, particularly smokers, show a statistically significant increase in the prevalence of severe periodontitis. OC users had deeper probing depths (>or=5 mm) than non-users. Moreover, OC users had higher gingival index scores and clinical attachment loss, >or=2 and >or=5 mm, respectively, than non-users (P <0.01). Patients taking OCs had significantly higher numbers of cultures positive for Candida. Seven Candida species were isolated. Subgingival Candida was associated with P. gingivalis and P. intermedia in 82.9% and 85.4%, respectively, in patients taking OCs. A. actinomycetemcomitans was isolated in patients with moderate and severe periodontitis and was associated with subgingival P. gingivalis, P. intermedia, and Candida. CONCLUSIONS: OC use may increase the risk of severe periodontitis and seems to cause a selection of certain Candida species in periodontal pockets. OC users showed a higher prevalence of P. gingivalis, P. intermedia, and A. actinomycetemcomitans compared to non-users. C. albicans, C. parapsilosis, C. krusei, C. tropicalis, and C. glabrata were the species with the ability to survive in the conditions created by the sex hormones after 3 years.

Prevalence of Staphylococcus spp and Candida spp in the oral cavity and periodontal pockets of periodontal disease patients

The oral cavity can act as a reservoir of certain pathogens that can cause systemic infections. The periodontal pocket is an ecological niche appropriate for hosting microorganisms that could act as opportunistic pathogens. The ability of Staphylococcus spp and Candida spp to form a biofilm and live within certain niches allows them to develop mechanisms that increase persistence, such as the evasion of host defenses and antibiotic efficacy. These microorganisms can easily be or become resistant to antibiotics and lead to superinfection. The aims of this study were to assess the presence of Staphylococcus aureus and Staphylococcus spp in biofilm in subgingival plaque and oral cavity of individuals with gingival-periodontal disease, to identify isolates and the relationship with Candida spp. The study included eighty-two patients, aged 18-70 years with periodontal disease and at least two sites with probing depth ≥3 mm. Participants’ data were evaluated individually. Subgingival biofilm samples were obtained using Gracey curettes 7/8, after supragingival biofilm removal, and a sample from the oral cavity (buccal mucosa, tongue and cheek mucosa) by sterile swab. Of all the patients studied, 42.7% exhibited Staphylococcus spp in the periodontal pocket and 69.5% in the oral cavity while 25.6% exhibited Candida spp in the periodontal pocket and 42.7% in the oral cavity. However, 13.4% had both microorganisms in the periodontal pocket and 36.6% in the oral cavity. The prevalence of Staphylococcus aureus was 13.4% in the periodontal pocket and 15.8% in the oral cavity. Candida albicans was the most prevalent yeast in the periodontal pocket (76.2%) and in the oral cavity (63.0%).

La cavidad bucal puede actuar como reservorio de ciertos patógenos que pueden producir infecciones sistémicas. La bolsa periodontal es un nicho ecológico propicio para albergar microorganismos que podrian actuar como patógenos oportunistas. La posibilidad que Staphylococcus spp y Candida spp puedan formar un biofilm o biopelícula y vivir dentro de ciertos nichos les permite a estos microorganismos desarrollar ciertos mecanismos que aumentan su persistencia como ser la capacidad de eludir las defensas del huésped y la terapia antimicrobiana. Estos microorganismos pueden ser o fácilmente convertirse en resistentes a los antibióticos y dar origen a una supeinfección. El propósito de este estudio fue evaluar la presencia de Staphylococcus aureus y Staphylococcus spp en biofilm placa subgingival y en cavidad oral en sujetos con enfermedad gingivoperiodontal, identificar los microorganismos aislados y su relación con la portación de Candida spp. El estudio incluyo ochenta y dos pacientes, de edades entre 18 a 70 anos de edad, con enfermedad periodontal, y al menos dos sitios con la profundidad de sondaje ≥ 3 mm. Se evaluaron los datos individuales. Las muestras de biofilm subgingival fueron obtenidas con cureta tipo Gracey 7/8, previa remoción del biofilm supragingival y una muestra de cavidad oral (mucosa, lengua y carrillo) mediante hisopo estéril. Del total de los pacientes estudiados, el 42,7% mostraron Staphylococcus spp en la bolsa y el 69,5% en la cavidad oral, mientras que 25,6% mostraron Candida spp en la bolsa y 42,7% en la cavidad oral. Sin embargo, el 13,4% tenían ambos microorganismos en la bolsa y el 36,6% en la cavidad oral. La prevalencia de Staphylococcus aureus en la bolsa periodontal fue de 13,4% y 15,8% en la cavidad oral. Candida albicans fue la levadura más frecuente en la bolsa periodontal (76,2%) y en la cavidad oral (63,0%).

Genetic relatedness of subgingival and buccal Candida dubliniensis isolates in immunocompetent subjects assessed by RAPD-PCR.

BACKGROUND: It is recognized that Candida dubliniensis commonly colonizes oral and subgingival sites in immunocompetent subjects with periodontal disease. OBJECTIVE: Since there are few data available on genetic characterization of C. dubliniensis in periodontal pockets and other oral sites, the aim of this study was to characterize subgingival and mucosal C. dubliniensis isolates recovered from immunocompetent subjects and to assay the genetic similarity of such isolates from both niches in the same patient by random amplified polymorphic DNA (RAPD). DESIGN: C. dubliniensis recovered from subgingival plaque and from buccal cavity samples were studied in 240 immunocompetent non-smoking individuals. Arbitrary amplification was carried out by RAPD-polymerase chain reaction (PCR). RESULTS: RAPD analysis showed identical genotypes of C. dubliniensis in different sampling sites (buccal cavity and subgingival areas) in eight of 10 patients except for those derived from two participants who presented presumably unrelated isolates. CONCLUSIONS: On the basis of the findings presented, the origin of the colonization of C. dubliniensis in subgingival biofilm seems to be the buccal cavity in a single patient. Consequently, it may be assumed that most of C. dubliniensis in these sites arise from the endogenous commensal strains.

Survival of Staphylococcus aureus on fomites.

The aim of this study was to evaluate duration of survival of Staphylococcus aureus on contaminated standardized fomites, such as sterilization paper (SP) and polyester previously sterilized in a steam autoclave, and to determine the potential inhibitory effects of the substrates (fabrics used to manufacture garments and special wrapping paper used in the dental setting) using the bacteriostasis test. The test was performed on two types of sterile standardized samples (T1 and T2). Sterility of the samples was validated following the protocol in use at the Department of Microbiology, after which the samples were inoculated with 50 microl of a calibrated suspension of Staphylococcus aureus (reference strain ATCC 25923) in the exponential growth phase, in a final concentration of 10(7) cfu/ml and 10(6) cfu/ml). The samples were incubated at 27 degrees C and survival and concentration of microorganisms attached to the surface of the substrates was determined at the following experimental time points: immediately post-contamination, and 3 hours, 24 hours, 3 days, and 7 days post-contamination. Recovery was determined and expressed as a percentage; the bacteriostasis test was performed and showed negative results. Our results suggest that the quantity of recovered microorganisms varies according to the type of substrate and that there is a relation between survival and incubation time of the inoculated substrate serving as an artificial niche.

Subgingival distribution of yeast and their antifungal susceptibility in immunocompetent subjects with and without dental devices.

Yeasts colonize the subgingival biofilm, which becomes a reservoir that favors their reproduction. The purpose of the present work was to determine the prevalence of yeasts of the Candida genus in the subgingival biofilm of gingivoperiodontal disease patients, including users and non-users of dental devices, and their susceptibility to fluconazole and voriconazole. Samples of subgingival pockets of immunocompetent nonsmokers showing gingivitis and periodontitis were inoculated in a differential chromogenic medium. Sixty three percent of subjects used dental devices. Yeasts were identified and susceptibility to fluconazole and voriconazole was tested following CLSI M44-A standards. The prevalence of yeasts in the subgingival biofilm was 40% CI 95% (30.5-50.3); 10% were patients who did not use dental appliances. The most frequently observed yeasts were C. albicans, and C. parapsilosis, C. dubliniensis, C. tropicalis and C. guilliermondii. Only C. dubliniensis and C. guilliermondii showed resistance to azoles. The use of dental devices significantly increased the prevalence of yeasts in periodontal pockets inpatients presenting gingivitis. It is noteworthy that non albicans Candida species, such as C. dubliniensis and C. guilliermondii, considered emerging species, which have a diminished susceptibility to antifungal agents were found in the crevicular fluid of immunocompetent patients.

Subgingival distribution of yeast and their antifungal susceptibility in immunocompetent subjects with and without dental devices

Las levaduras del genero Candida colonizan el biofilm subgingival.Su hallazgo constituye un reservorio favorable para su multiplicación. El propósito de éste trabajo fue investigar la presencia de levaduras del género Candida en el biofilm subgingivalde individuos con enfermedad gingivoperiodontal a fin de establecer la prevalencia de especies y los perfiles desusceptibilidad a fluconazol y voriconazol de las mismas. Se obtuvieron muestras del biofilm subgingival en cien pacientes inmunocompetentes, no fumadores, con salud gingivoperiodontal, gingivitis y periodontitis, con y sin aparatologíabucal. Las muestras se sembraron en medio cromogénico diferencial y las levaduras aisladas se identificaronmediante micromorfología y pruebas bioquímicas. Los estudios de sensibilidad a fluconazol y voriconazol se realizaron según las normas CLSI M44-A. La prevalencia de levadurasen el biofilm subgingival fue del 40 por ciento IC95 por ciento (30.5-50.3) siendo el 10 por ciento y 30 por ciento la frecuencia de las mismas para los pacientes sin y con aparatología bucal respectivamente.C. albicans fue la levadura más frecuente. Encontramos otras especies como C. parapsilosis, C. dubliniensis, C. tropicalis, C. guilliermondii y C. sake. Solo se observó resistencia a los azoles en C. dubliniensis y C. guilliermondii. El tratamiento con aparatología bucal incrementó la prevalencia de levadurasen bolsa periodontal en forma significativa. Es importante destacar la presencia en el fluido subgingival de especies de Candida no albicans consideradas emergentes y con sensibilidad disminuida a los antifúngicos como C. dubliniensisy C. guilliermondii (AU)

Yeasts colonize the subgingival biofilm, which becomes a reservoir that favors their reproduction. The purpose of the present work was to determine the prevalence of yeasts of the Candida genus in the subgingival biofilm of gingivoperiodontal disease patients, including users and non-users of dental devices, and their susceptibility to fluconazole and voriconazole. Samples of subgingival pockets of immunocompetent nonsmokers showing gingivitis and periodontitis were inoculated in a differential chromogenic medium. Sixty three percent of subjects used dental devices. Yeasts were identified and susceptibility to fluconazole and voriconazole was tested following CLSI M44-A standards. The prevalence of yeasts in the subgingival biofilm was 40% CI 95% (30.5-50.3); 10% were patients who did not use dental appliances. The most frequently observed yeasts were C. albicans, and C. parapsilosis, C. dubliniensis, C. tropicalis and C. guilliermondii. Only C. dubliniensis and C. guilliermondii showed resistance to azoles. The use of dental devices significantly increased the prevalence of yeasts in periodontal pockets inpatients presenting gingivitis. It is noteworthy that non albicans Candida species, such as C. dubliniensis and C. guilliermondii, considered emerging species, which have a diminished susceptibility to antifungal agents were found in the crevicular fluid of immunocompetent patients.(AU)

Subgingival distribution of yeast and their antifungal susceptibility in immunocompetent subjects with and without dental devices

Las levaduras del genero Candida colonizan el biofilm subgingival.Su hallazgo constituye un reservorio favorable para su multiplicación. El propósito de éste trabajo fue investigar la presencia de levaduras del género Candida en el biofilm subgingivalde individuos con enfermedad gingivoperiodontal a fin de establecer la prevalencia de especies y los perfiles desusceptibilidad a fluconazol y voriconazol de las mismas. Se obtuvieron muestras del biofilm subgingival en cien pacientes inmunocompetentes, no fumadores, con salud gingivoperiodontal, gingivitis y periodontitis, con y sin aparatologíabucal. Las muestras se sembraron en medio cromogénico diferencial y las levaduras aisladas se identificaronmediante micromorfología y pruebas bioquímicas. Los estudios de sensibilidad a fluconazol y voriconazol se realizaron según las normas CLSI M44-A. La prevalencia de levadurasen el biofilm subgingival fue del 40 por ciento IC95 por ciento (30.5-50.3) siendo el 10 por ciento y 30 por ciento la frecuencia de las mismas para los pacientes sin y con aparatología bucal respectivamente.C. albicans fue la levadura más frecuente. Encontramos otras especies como C. parapsilosis, C. dubliniensis, C. tropicalis, C. guilliermondii y C. sake. Solo se observó resistencia a los azoles en C. dubliniensis y C. guilliermondii. El tratamiento con aparatología bucal incrementó la prevalencia de levadurasen bolsa periodontal en forma significativa. Es importante destacar la presencia en el fluido subgingival de especies de Candida no albicans consideradas emergentes y con sensibilidad disminuida a los antifúngicos como C. dubliniensisy C. guilliermondii

Yeasts colonize the subgingival biofilm, which becomes a reservoir that favors their reproduction. The purpose of the present work was to determine the prevalence of yeasts of the Candida genus in the subgingival biofilm of gingivoperiodontal disease patients, including users and non-users of dental devices, and their susceptibility to fluconazole and voriconazole. Samples of subgingival pockets of immunocompetent nonsmokers showing gingivitis and periodontitis were inoculated in a differential chromogenic medium. Sixty three percent of subjects used dental devices. Yeasts were identified and susceptibility to fluconazole and voriconazole was tested following CLSI M44-A standards. The prevalence of yeasts in the subgingival biofilm was 40% CI 95% (30.5-50.3); 10% were patients who did not use dental appliances. The most frequently observed yeasts were C. albicans, and C. parapsilosis, C. dubliniensis, C. tropicalis and C. guilliermondii. Only C. dubliniensis and C. guilliermondii showed resistance to azoles. The use of dental devices significantly increased the prevalence of yeasts in periodontal pockets inpatients presenting gingivitis. It is noteworthy that non albicans Candida species, such as C. dubliniensis and C. guilliermondii, considered emerging species, which have a diminished susceptibility to antifungal agents were found in the crevicular fluid of immunocompetent patients.

Aislamiento de Candida dubliniensis en un adolescente con estomatitis protésica / Isolation of Candida dubliniensis in a teenager with denture stomatitis

Objetivos: Utilizar varios métodos que permiten la diferenciación entre Candida albicans y Candida dubliniensis en un intento deconocer si C. dubliniensis puede ser aislada de la cavidad oral de adolescentes con prótesis ortopédicas orales. Materiales y métodos: Se aislaron 12 cepas de género Candida procedentes de mucosa palatina y de soporte de prótesis de 12 pacientes adolescentes portadores de prótesis ortopédicas orales. Para la diferenciación entre C. albicans y C. dubliniensis se utilizaron varias pruebas fenotípicas (la asimilación de fuentesde carbono con el método comercial ID 32C, el crecimiento enagar glucosado de Sabouraud a 45 ºC, la producción abundante de clamidosporas en agar caseína, y la reactividad mediante inmunofluorescencia indirecta con un antisuero específico para C. dubliniensis) y la reacción en cadena de la polimerasa(PCR). El serotipado de C. albicans se realizó con el anticuerpo monoclonal B9E. Resultados: Los 12 pacientes estudiados presentaron una estomatitis protésica tipo 2 de Newton y en todos los casos se aislaron las mismas especies de la muestra de mucosa y de la de prótesis del mismo paciente. El CHRO Magar Candida y la prueba de la filamentación en suero permitieron diferenciar los aislamientos que daban lugar a colonias de color verde y filamentaban de los que daban colonias violetas y no lo hacían. Unicamente el aislamiento del paciente 8 fue positivo con el antisuero específico para C. dubliniensis y produjo abundantes clamidosporas en agar caseína, mientras que ocho aislamientos no presentaron crecimiento a 45 ºC. La identificación de todos los aislamientos se consiguió con la prueba ID 32C, identificándose C. albicans en el75% de los pacientes, C. glabrata en el 16,6% y C. dubliniensis en el 8,3%. La PCR con iniciadores específicos para el tipadode C. dubliniensis permitió la identificación del aislamiento del paciente 8 como C. dubliniensis genotipo 1. Conclusión: C. dubliniensis puede ser aislada de la cavidad oral de adolescentes con estomatitis asociada a prótesis ortopédicas y es posible, y técnicamente asequible, la diferenciación entre C. albicans y C. dubliniensis mediante la realización de pruebas como el ID 32C, la observación de abundantes clamidosporas en agar caseína, la reactividad con un antisuero específico para C. dubliniensis y la PCR

Objectives: Test several methods that allow the differentiation between Candida albicans and Candida dubliniensis, in an attempt to assess whether C. dubliniensis can be recovered from the oral cavity of teenagers wearing orthopedic oral prostheses. Material and Methods: Twelve Candida strains were isolated from the prosthesis as well as the palatal mucosa in contact with the dental prosthesis from 12 teenager patients wearing orthopedic oral prostheses. Differentiation between C. albicans and C. dubliniensis was achieved by a number of phenotypictests (carbon assimilation by the commercially available ID32C test, growth at 45ºC on Sabouraud glucose agar, abundant chlamydospore production on Casein agar, and reactivity with a C. dubliniensis antiserum) and the polymerase chain reaction(PCR). Serotyping of C. albicans was performed with monoclonalantibody B9E. Results: All 12 patients studied presented a Newton`s type 2 denture stomatitis and in every patient the same Candida species were isolated from the prosthesis and the palatal mucosa in contact with the dental prosthesis. CHRO Magar Candida and the germ tube test allowed the differentiation of isolates giving green colonies and a positive germ tube test from those giving violet colonies and a negative germ tube test. Only the isolate from patient 8 was stained by the C. dubliniensis antiserum and showed abundant chlamydospore production on Casein agar. Eight isolates did not grow at 45 ºC. Identification of all isolates was obtained by the ID 32C test. C. albicans was identified in 75% of patients, C. glabrata in 16,6% and C. dubliniensis in 8,3%. By using specific primers for typing C. dubliniensis, PCRallowed the identification of patient´s 8 isolate as C. dubliniensisgenotype 1. Conclusion: C. dubliniensis can be isolated from the oral cavity of teenagers wearing orthopedic oral prostheses and it is possible and technically amenable, the differentiation between C.albicans y C. dubliniensis using the ID 32C test, the observation of abundant chlamydospore production on Casein agar, there activity with a C. dubliniensis antiserum and the PCR

Isolation of Candida dubliniensis in a teenager with denture stomatitis.

OBJECTIVES: Test several methods that allow the differentiation between Candida albicans and Candida dubliniensis, in an attempt to assess whether C. dubliniensis can be recovered from the oral cavity of teenagers wearing orthopedic oral prostheses. MATERIAL AND METHODS: Twelve Candida strains were isolated from the prosthesis as well as the palatal mucosa in contact with the dental prosthesis from 12 teenager patients wearing orthopedic oral prostheses. Differentiation between C. albicans and C. dubliniensis was achieved by a number of phenotypic tests (carbon assimilation by the commercially available ID 32C test, growth at 45 grades C on Sabouraud glucose agar, abundant chlamydospore production on Casein agar, and reactivity with a C. dubliniensis antiserum) and the polymerase chain reaction (PCR). Serotyping of C. albicans was performed with monoclonal antibody B9E. RESULTS: All 12 patients studied presented a Newton s type 2 denture stomatitis and in every patient the same Candida species were isolated from the prosthesis and the palatal mucosa in contact with the dental prosthesis. CHROMagar Candida and the germ tube test allowed the differentiation of isolates giving green colonies and a positive germ tube test from those giving violet colonies and a negative germ tube test. Only the isolate from patient 8 was stained by the C. dubliniensis antiserum and showed abundant chlamydospore production on Casein agar. Eight isolates did not grow at 45 grades C. Identification of all isolates was obtained by the ID 32C test. C. albicans was identified in 75% of patients, C. glabrata in 16,6% and C. dubliniensis in 8,3%. By using specific primers for typing C. dubliniensis, PCR allowed the identification of patient s 8 isolate as C. dubliniensis genotype 1. CONCLUSION: C. dubliniensis can be isolated from the oral cavity of teenagers wearing orthopedic oral prostheses and it is possible and technically amenable, the differentiation between C. albicans y C. dubliniensis using the ID 32C test, the observation of abundant chlamydospore production on Casein agar, the reactivity with a C. dubliniensis antiserum and the PCR.

Viable spore counts in biological controls pre-sterilization.

The aim of the present study was to evaluate the total count of viable spores in standardized inoculated carriers pre-sterilization. Samples of "Bacterial Spore Sterilization Strip" (R Biological Laboratories) (well before their expiry date) were divided into Group A (B. subtilis) and Group B (B. stearothermophylus). Twenty-four strips were tested per group. The strips were minced in groups of three, placed in chilled sterile water and vortexed for 5 minutes to obtain a homogenous suspension. Ten ml of the homogenous suspension were transferred to two sterile jars, i.e. one jar per group. The samples were then heated in a water bath at 95 degrees C (Group A) or 80 degrees C (Group B) for 15 minutes and cooled rapidly in an ice bath at 0- 4 degrees C during 15 minutes. Successive dilutions were performed until a final aliquot of 30 to 300 colony-forming units (CFU) was obtained. The inoculums were placed in Petri dishes with culture medium (soy extract, casein agar adapted for spores, melted and cooled to 45-50 degrees C) and incubated at 55 degrees C or 37 degrees C. Statistical analysis of the data was performed. A larger number of spores were found at 48 hours than at 24 hours. However, this finding did not hold true for all the groups. The present results show that monitoring viable spores pre-sterilization would guarantee the accuracy of the data. Total spore counts must be within 50 and 300% of the number of spores indicated in the biological control. The procedure is essential to guarantee the efficacy of the biological control.

Viable spore counts in biological controls pre-sterilization.

The aim of the present study was to evaluate the total count of viable spores in standardized inoculated carriers pre-sterilization. Samples of [quot ]Bacterial Spore Sterilization Strip[quot ] (R Biological Laboratories) (well before their expiry date) were divided into Group A (B. subtilis) and Group B (B. stearothermophylus). Twenty-four strips were tested per group. The strips were minced in groups of three, placed in chilled sterile water and vortexed for 5 minutes to obtain a homogenous suspension. Ten ml of the homogenous suspension were transferred to two sterile jars, i.e. one jar per group. The samples were then heated in a water bath at 95 degrees C (Group A) or 80 degrees C (Group B) for 15 minutes and cooled rapidly in an ice bath at 0- 4 degrees C during 15 minutes. Successive dilutions were performed until a final aliquot of 30 to 300 colony-forming units (CFU) was obtained. The inoculums were placed in Petri dishes with culture medium (soy extract, casein agar adapted for spores, melted and cooled to 45-50 degrees C) and incubated at 55 degrees C or 37 degrees C. Statistical analysis of the data was performed. A larger number of spores were found at 48 hours than at 24 hours. However, this finding did not hold true for all the groups. The present results show that monitoring viable spores pre-sterilization would guarantee the accuracy of the data. Total spore counts must be within 50 and 300

of the number of spores indicated in the biological control. The procedure is essential to guarantee the efficacy of the biological control.

Long-term sterility of orthodontic-surgical appliances.

The aim of this study was to evaluate the long-term sterility of new dental appliances according to the non rigid wrapping employed and assess the effectiveness of sterilization in a steam autoclave at 134 degrees for 20 minutes using physical, chemical, and biological indicators. All the experimental (E) samples and the control samples (C) were assigned to one of three groups according to the type of packaging: paper bag (E1), paper/plastic pouch (E2), nylon tubing bag (E3). Each bag contained standardized orthodontic wires and brackets and sterility indicators. The samples were evaluated at the following experimental times: immediately, and 6, 12, 24 and 30 months post-sterilization. The samples were analyzed under aerobic and anaerobic conditions in keeping with the protocol currently in use at the Department of Microbiology, School of Dentistry, University of Buenos Aires. The group of control, non-sterilized samples (C1, C2, C3) were analyzed prior to the onset of the study, and were found to be contaminated. None of the sterilized samples in any of the three experimental groups evidenced contamination at any of the experimental times. The results showed that, under the present conditions, the packages and orthodontic appliances remained sterile for 30 months. These results show the importance of controlling sterility and the storage conditions over time for all the orthodontic/surgical appliances used in invasive treatments.

Long-term sterility of orthodontic-surgical appliances.

The aim of this study was to evaluate the long-term sterility of new dental appliances according to the non rigid wrapping employed and assess the effectiveness of sterilization in a steam autoclave at 134 degrees for 20 minutes using physical, chemical, and biological indicators. All the experimental (E) samples and the control samples (C) were assigned to one of three groups according to the type of packaging: paper bag (E1), paper/plastic pouch (E2), nylon tubing bag (E3). Each bag contained standardized orthodontic wires and brackets and sterility indicators. The samples were evaluated at the following experimental times: immediately, and 6, 12, 24 and 30 months post-sterilization. The samples were analyzed under aerobic and anaerobic conditions in keeping with the protocol currently in use at the Department of Microbiology, School of Dentistry, University of Buenos Aires. The group of control, non-sterilized samples (C1, C2, C3) were analyzed prior to the onset of the study, and were found to be contaminated. None of the sterilized samples in any of the three experimental groups evidenced contamination at any of the experimental times. The results showed that, under the present conditions, the packages and orthodontic appliances remained sterile for 30 months. These results show the importance of controlling sterility and the storage conditions over time for all the orthodontic/surgical appliances used in invasive treatments.