Review: modulation of the oral microbiome by the host to promote ecological balance

Abstract

The indivisible relationship between the human host and its oral microbiome has been shaped throughout the millennia, by facing various changes that have forced the adaptation of oral microorganisms to new environmental conditions. In this constant crosstalk between the human host and its microbiome, a bidirectional relationship has been established. The microorganisms provide the host with functions it cannot perform on its own and at the same time the host provides its microbes with a suitable environment for their growth and development. These host factors can positively affect the microbiome, promoting diversity and balance between different species, resulting in a state of symbiosis and absence of pathology. In contrast, other host factors can negatively influence the composition of the oral microbiome and drive the interaction towards a dysbiotic state, where the balance tilts towards a harmful relationship between the host and its microbiome. The aim of this review is to describe the role host factors play in cultivating and maintaining a healthy oral ecology and discuss mechanisms that can prevent its drift towards dysbiosis.

Environmental factors and periodontal microbiome

“…Studies investigating possible modulation by diet have mainly focused on a pathologic perspective and the effects on oral microbiome remain largely obscure. 9 Dietary intake directly affects endogenous nutrients in the oral cavity through systemic circulation. 104 Possible relationships between microbial diversity in saliva and specific diet types such as carnivore, omnivore, and vegan were investigated in 161 individuals but none were found.…”

“…A reciprocal and dynamic balance between the human host and its microorganisms determines oral health. 9…”

Oral Microbiome Metabarcoding in Two Invasive Small Mammals from New Zealand

“…These may include genetic and physiological factors, as well as differences in the environment prior to capture. These need to be taken into consideration to better understand the complexity of microbiome diversity [85][86][87][88]. Diet has been suggested as one of the major determinants of oral microbial diversity [75][76][77][78].…”

A Study Protocol to see Change of Nasal and Oropharyngeal Microbiome with Prolonged Use of Medical Masks during the COVID-19 Outbreak in Healthy Participants

“…Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Spirochaetes, and Fusobacteria form the major community structure of our oral microbiome, while 4% of species belong to other phyla [7]. A crosstalk goes on between the microbiome and its host, and that is highly in uenced by various lifestyles and behaviors like dietary preferences, substance consumption -such as tobacco or drugs, oral hygiene practices [8]. The microbiome constituents of the upper respiratory tract are different in adults and infants, but there is a similarity in the niche characteristics.…”