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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
Infective endocarditis by Actinomyces species: a systematic review
Published in Journal of Chemotherapy, 2023
Petros Ioannou, Stella Baliou, Ioanna Papakitsou, Diamantis P. Kofteridis
Actinomyces species are Gram-positive bacteria that colonize the mouth, colon, and vagina and are the causes of actinomycosis, which is a slowly progressive infection that may mimic malignancy due to the invasiveness of tissues and the ability to form sinus tracts [1]. The most common encountered species associated with actinomycosis is A. israeilii [2]. Other species that may also cause actinomycosis, even though they are less frequently encountered are Actinomyces naeslundii, Actinomyces viscosus, Actinomyces odontolyticus, Actinomyces gerencseriae, Actinomyces graevenitzii, and Actinomyces meyeri [3–9]. With development of newer methods for pathogen identification, such as MALDI-TOF and genotypic methods such as comparative 16S ribosomal RNA (rRNA), new Actinomyces species have been identified from both human and animal specimens [6,10,11]. On the other hand, some Actinomyces species have been reclassified as Trueperella, Actinotignum, or Cellulomonas due to the same pathogen identification methods [6,10–14].
Integrative multiomics analysis reveals host-microbe-metabolite interplays associated with the aging process in Singaporeans
Published in Gut Microbes, 2022
Liwei Chen, Tingting Zheng, Yifan Yang, Prem Prashant Chaudhary, Jean Pui Yi Teh, Bobby K. Cheon, Daniela Moses, Stephan C. Schuster, Joergen Schlundt, Jun Li, Patricia L. Conway
In contrast to many studies investigating the relationships between the gut microbiota and age, the associations of oral microbiota with age have only recently started to attract the attention of researchers. Percival et al. found that the abundance of Actinomyces species, especially Actinomyces naeslundii and Actinomyces oris, are significantly higher in the supragingival biofilm of subjects over 60 years of age.18 Another study demonstrated that compared with young subjects, older people have a higher prevalence of enteric bacilli and Pseudomonas species.19 Accumulating evidence has revealed that the decline in host immunity and general functionality during aging are partially attributed to the composition shift of the oral microbiota and the feedback loop of the transition of oral bacteria to the gastrointestinal tract.13,20 This highlights the necessity to investigate the role of the oral microbiome during the aging process.
Chronic non-bacterial osteomyelitis masquerading as fibrous dysplasia
Published in Modern Rheumatology Case Reports, 2020
Tessa N. Campbell, Bevan Frizzell, Paul MacMullan
She subsequently underwent three separate biopsies of her right jaw over the course of 5 years. Biopsies indicated bony tissue/trabeculae of woven bone in a fibrous stromal background with small pockets of inflammation, most consistent with fibro-osseous dysplasia. Unlike CNO which tends to have patchy fibrosis, fibrous dysplasia usually has uniform fibrosis. An infectious workup revealed scant Actinomyces naeslundii and bacteria consistent with oral flora or likely contamination (scant Streptococcus viridans, scant Coagulase negative Staphylococcus, scant Propionibacterium acnes/avidum, scant Veillonella species, one colony of Rothia dentocariosa). Though the isolation of Propionibacterium acnes has been reported in bone biopsies of some SAPHO patients, antibiotics fail to achieve clinical improvement in most instances, as was the case with our patient. It has therefore been proposed that P. acnes may act as an antigen that triggers an immunological response and leads to inflammation [10,11]. In the absence of a true infection and with suggestive biopsy results, the patient was therefore initially diagnosed with fibrous dysplasia. She did not have any hearing loss, scoliosis, hyperfunctioning endocrinopathies or café au lait skin macules that can be associated with fibrous dysplasia.