Mouth breathing subjects show a significant 4 times higher risk to develop Streptococcus mutans (S. mutans) and an increased level of plaque index (PI). Plaque is a sticky substance from leftover food particles. A build up of plaque is not good for dental health and can cause gum disease.
The group of mouth breathers may retain a greater amount of bacteria in their mouth, possibly due to the evaporation of water from the saliva of constant mouth breathers.
Mummolo S, Nota A, Caruso S, Quinzi V, Marchetti E, Marzo G. Salivary Markers and Microbial Flora in Mouth Breathing Late Adolescents. Biomed Res Int. 2018 Mar 5;2018:8687608. https://pubmed.ncbi.nlm.nih.gov/29693018/
