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Dental Caries: Dietary and Microbiology Factors
Published in Lars Granath, William D. McHugh, Systematized Prevention of Oral Disease: Theory and Practice, 2019
William H. Bowen, Dowen Birkhed
The microbial flora in plaque is diverse. Its composition is dependent on, for example, site of the tooth, age of plaque, and composition of the diet. Although S. mutans is a most important constituent it rarely dominates the plaque flora. S. sanguis and S. mitior are the predominant streptococci in plaque. Actinomyces spp. including Actinomyces naeslundii, A. viscosus, and A. israelii are frequently found in large numbers. The lactobacilli which are among the most aciduric organisms found in dental plaque are usually present in low numbers. However, as carious lesions develop and progress, they constitute an increasingly large proportion of the flora within the lesions. Neisseria and Veillonella are consistently isolated from dental plaque. The latter are unique in that they can use lactate as a source of energy. Recently increasing attention has been given to the Peptostreptococci which can play an important role in the nitrogen metabolism of dental plaque. All the available evidence suggests that any dental plaque is clearly potentially cariogenic; whether the potential is realized is heavily dependent of the frequent ingestion of sugars.26
Bacterial Infections of the Oral Cavity
Published in K. Balamurugan, U. Prithika, Pocket Guide to Bacterial Infections, 2019
P. S. Manoharan, Praveen Rajesh
Most Actinomyces are soil organisms, the potentially pathogenic species are commensals of the mouth in humans and animals. A number of Actinomyces species are isolated from the oral cavity. These include A. israelii, A. gerencseriae, A. odontolyticus, A. naeslundii (genospecies I and 2), A. myeri, and A. georgiae. They are gram-positive filamentous branching rods that are non-motile, non-sporing, and non-acid-fast. Clumps of the organisms can be seen as yellowish “sulfur granules” in pus discharging from sinus tracts, or the granules can be squeezed out of the lesions. The colonies resemble breadcrumbs or the surface of “molar” teeth. Sulfur granules in lesions are a clue to their presence. When possible, these granules should be crushed, gram-stained, observed for gram-positive and branchin filaments, and also cultured in preference to pus (Samaranayake, 2006).
Cervicofacial Infections
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
Actinomycosis is caused by Gram-positive non-spore forming bacteria. The most common human pathogen is Actinomyces israelii but there are several other species which can rarely be pathogenic. Approximately 50% of cases are cervicofacial. Actinomyces are normal commensals in the oral cavity and infections arise from a breach of the mucosa (e.g. dental extraction). The most common presentation is a slow-growing painless mass near the mandible. Local lymph nodes may be involved and in a small number of cases metastasis of disease to liver or brain may occur. Untreated, the mass progresses to fibrosis and chronic suppuration with draining sinuses. A less common presentation is with an acute, warm, tender mass with fever. The presence of sulphur granules on pathological examination is suggestive but not diagnostic. If the diagnosis is suspected, special culture conditions increase the chance of culturing this organism. Most cases are treated by surgical excision followed by prolonged antibacterial therapy, usually penicillin for up to 6 months.
Infective endocarditis by Actinomyces species: a systematic review
Published in Journal of Chemotherapy, 2023
Petros Ioannou, Stella Baliou, Ioanna Papakitsou, Diamantis P. Kofteridis
The mean age of patients diagnosed with Actinomyces spp. IE in this study was 48.3 years, which is lower than the age in other cohorts of patients with IE, where mean age is about 70 years [54–56]. A male predominance among patients with IE by Actinomyces spp. was noted, which is also the case in IE in the general population by other microorganisms [54,56]. A prosthetic valve was present in 12.9% of patients with IE by Actinomyces spp., which was comparable to the rate noted in other studies of IE where that rate was up to 50% [54–56]. A previous episode of IE in the present study was found to be present in 9.7%, and the same was the rate of patients that had rheumatic fever which are both similar as in other studies in patients with IE in the literature [55,56].
Mucoid-producing lesion following hip arthroplasty
Published in Baylor University Medical Center Proceedings, 2022
Rachel Vopni, Katherine E. Dowd, Erin T. Bird
The manifestation of this patient’s fistula as a mucoid-producing bladder tumor made etiological identification difficult. Focal bladder masses that may mimic malignancy are a diagnostic dilemma.5 In this case, the etiology of the bladder lesion was neither malignant nor a focal bladder mass, supporting the unusual nature of this patient’s bladder lesion etiology and the relative difficulty in diagnosis. Additionally, late THA infection by A. israelii is unusual and due to hematogenous seeding from endogenous sites, like the genitourinary system and colon where there can be colonization.6 Following its introduction with disruption of normal mucosal barriers through trauma, surgery, or infection, the Actinomyces genus has demonstrated the ability to invade tissue layers, causing formation of abscesses and fistulae.7 Based on this case and similar cases, orthopedists should be aware of potential long-term bladder complications in post-THA patients, and urologists should consider the patient’s orthopedic history in the evaluation of unusual urological symptoms that do not resolve with standard therapies.
Oral prosthetic microbiology: aspects related to the oral microbiome, surface properties, and strategies for controlling biofilms
Published in Biofouling, 2021
Douglas Roberto Monteiro, Victor Eduardo de Souza Batista, Anne Caroline Morais Caldeirão, Rogério de Castilho Jacinto, Juliano Pelim Pessan
In cases of peri-implant diseases, increased levels of Actinomyces spp., Prevotella nigrescens, P. gingivalis, N. mucosa, Fusobacterium spp. and Capnocytophaga ochracea are detected in mucositis patients. On the other hand, increased levels of Actinomyces spp., Fusobacterium spp., P. gingivalis, P. intermedia, Streptococcus gordonii, Streptococcus sanguinis, T. forsytha, T. denticola, F. nucleatum, and V. parvula were found in peri-implantitis patients (Máximo et al.2009; Costa et al.2019). Taxonomic characterization by next-generation sequencing has shown differences in the microbiome of patients rehabilitated with dental implants, both under healthy or diseased conditions, as recently revised by Belibasakis and Manoil (2021).