Oral Bacteria: Friends and Foes?

Dear Colleagues,

A human oral cavity harbors more than 700 microbial species. These microbes form a complex and diverse microbial community and inhabit different niches as oral biofilms. In a healthy state, the oral biofilm and the host tissue maintain a delicate balance and form a symbiotic relationship. Upon environmental stresses, for example, poor oral hygiene, the biofilm community can shift from homeostasis to dysbiosis, represented by an outgrowth of pathogenic species and a reduction in beneficial species, leading to a breakdown of the abovementioned symbiotic relationship, and eventually oral infections, including dental caries, periodontitis, and peri-implantitis. This ecological concept indicates that not all resident oral microbes are foes, but some might be friends of the host. Some of them might be opportunistic, switching from friends to foes and vice versa, depending on the environment.

The conventional strategies for preventing or treating oral infections have been focused on oral biofilm killing. The commonly used mouth rinses often contain broad-spectrum antimicrobials. The indiscriminative killing of the entire microbial population by antimicrobials may suppress the friends of the host and perturb the oral ecology, consequently jeopardizing the long-term clinical treatment effect. The attention for oral biofilm control should turn to the restoration of a health-compatible microbial community.

This Special Issue aims to discuss the roles of both beneficial and pathogenic bacteria in oral infections and explore novel ecological approaches to control oral biofilms. It welcomes original papers and reviews that investigate and discuss at least one of the following: (1) Molecular insights on the roles of oral beneficial and pathogenic bacteria in oral infections; (2) interaction between oral bacteria (beneficial/pathogenic) and host; (3) interaction between oral beneficial bacteria and pathogenic bacteria; (4) application of microbiome modulation to maintain oral health; and (5) novel strategies to control oral polymicrobial biofilms.

Dr. Dongmei Deng
Dr. Lei Cheng
Dr. Alessandra Nara de Souza Rastelli
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Pathogens is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• oral beneficial bacteria
• oral pathogenic bacteria
• host–microbe interaction
• oral microbiome
• oral biofilms
• microbiome modulation