Complete Genome Sequence of Streptococcus oralis 34

Streptococcus oralis is an early colonizer and one of the most abundant species found in the human oral cavity. We report the complete genome sequence of S. oralis 34 (1,920,884 bp; GC content, 41.3%), commonly used in many oral microbiology studies exploring bacterial attachment and interaction(s) within mixed-species model systems.

A review of in vitro attempts to develop the axenic culture of Treponema pallidum and genomics-based suggestions to achieve this elusive goal

To date, the axenic culture of Treponema pallidum remains a challenge in the field of microbiology despite countless attempts. Here, we conducted a comprehensive bibliographic analysis using several databases and search engines, namely Pubmed, Google scholar, Google, Web of Science and Scopus. Numerous unsuccessful empiric studies have been conducted and evaluated using as criteria dark-field microscopic observation of motile spiral shaped cells in the culture and virulence of the culture through rabbit infectivity. All of these studies failed to induce rabbit infectivity, even when deemed positive after microscopic observation leading to the misnomer of avirulent T. pallidum . In fact, this criterion was improperly chosen because not all spiral shaped cells are T. pallidum . However, these studies led to the formulation of culture media particularly favourable to the growth of several species of Treponema, including Oral Microbiology and Immunology, Zürich medium (OMIZ), Oral Treponeme Enrichment Broth (OTEB) and T-Raoult, thus allowing the increase in the number of cultivable strains of Treponema . The predicted metabolic capacities of T. pallidum show limited metabolism, also exhibited by other non-cultured and pathogenic Treponema species, in contrast to cultured Treponema species. The advent of next generation sequencing represents a turning point in this field, as the knowledge inferred from the genome can finally lead to the axenic culture of T. pallidum .

COMPARATIVE CHARACTERISTICS OF THE MICROBIOLOGICAL PARAMETERS OF THE ORAL CAVITY DURING PROSTHETICS WITH REMOVABLE PROSTHESES BASED ON IMPLANTS

On patients with removable and conditionally removable prostheses supported on implants, the microbiocenosisof the oral cavity was studied in the dynamics of observation. All patients were divided into 2 groups: 1 group consisted of 15 patient’s prosthetics with removable dentures on dental implants; Group 2 consisted of 15 patients prosthetic with conditionally removable dentures on dental implants. The material for the study was a washout from the oral cavity. The study of changes in themicrobiocenosis of the oral cavity in patients with conditionally removable dentures relative to theindicators in the earlystages of prosthetics, showed mainly a decrease in the quantitative indicators of all types of microorganisms.Keywords:implant, prosthesis, conditionally removable prosthetics, microbiocenosis, oral microbiology

Dysbiosis From a Microbial and Host Perspective Relative to Oral Health and Disease

The significance of microbiology and immunology with regard to caries and periodontal disease gained substantial clinical or research consideration in the mid 1960's. This enhanced emphasis related to several simple but elegant experiments illustrating the relevance of bacteria to oral infections. Since that point, the understanding of oral diseases has become increasingly sophisticated and many of the original hypotheses related to disease causality have either been abandoned or amplified. The COVID pandemic has reminded us of the importance of history relative to infectious diseases and in the words of Churchill “those who fail to learn from history are condemned to repeat it.” This review is designed to present an overview of broad general directions of research over the last 60 years in oral microbiology and immunology, reviewing significant contributions, indicating emerging foci of interest, and proposing future directions based on technical advances and new understandings. Our goal is to review this rich history (standard microbiology and immunology) and point to potential directions in the future (omics) that can lead to a better understanding of disease. Over the years, research scientists have moved from a position of downplaying the role of bacteria in oral disease to one implicating bacteria as true pathogens that cause disease. More recently it has been proposed that bacteria form the ecological first line of defense against “foreign” invaders and also serve to train the immune system as an acquired host defensive stimulus. While early immunological research was focused on immunological exposure as a modulator of disease, the “hygiene hypothesis,” and now the “old friends hypothesis” suggest that the immune response could be trained by bacteria for long-term health. Advanced “omics” technologies are currently being used to address changes that occur in the host and the microbiome in oral disease. The “omics” methodologies have shaped the detection of quantifiable biomarkers to define human physiology and pathologies. In summary, this review will emphasize the role that commensals and pathobionts play in their interaction with the immune status of the host, with a prediction that current “omic” technologies will allow researchers to better understand disease in the future.

Probiyotiklerin Diş Çürüklerinin Oluşumu Üzerine Etkisi

According to the report of World Health Organization / Food and Drug Administration, probiotics are expressed as, ‘‘live microorganisms that have a positive effect on the health of the host when consumed in sufficient quantities’’. People use probiotics to treat diseases and to promote general health. Probiotic bacteria should adhere to the tooth surface to prevent and slow down the tooth decay and also should join to the microbial dental plaque bacteria. However, probiotic bacteria should damage and compete with the cariogenic bacteria and prevent the growth of bacteria. In addition, probiotic bacteria should be able to reduce the acid production by affecting the carbohydrate metabolism. Probiotic is a new and interesting research topic in oral microbiology and oral diseases. A wide range of epidemiological investigations will demonstrate the different benefits of probiotics on human health.