The oral flora is the totality of microorganisms that colonize the oral cavity of humans. A functioning oral flora forms an important prerequisite for dental health.
What is the oral flora?
The oral flora is the totality of microorganisms that colonize the oral cavity of humans. Oral flora refers to all microorganisms that colonize the human oral cavity. The term flora goes back to the earlier assumption that microorganisms such as bacteria belong to the plant kingdom. In modern times, the oral flora within dentistry is called a microorganism society or microorganism community. The colonization of the oral flora of humans takes place immediately after birth. Among the first bacterial species to populate the mouth are streptococci. Prior to this, the oral cavity of the growing fetus is still free of microorganisms. Only after the birth process do the germs have the opportunity to colonize the oral cavity. In the course of time, the oral flora becomes more and more complex. If teeth are lost in old age, it is possible that the oral flora will regress again. A distinction can be made between resident and transient oral flora, which depends on whether the oral cavity is colonized by the microorganisms permanently or only temporarily.
Function and task
The microorganisms that make up the oral flora primarily include hundreds of different species of bacteria as well as yeast fungi. These include, for example, streptococci such as Streptococcus salivarius, Streptococcus sanguis and Streptococcus mitis, lactobacilli, actinomycetes, neisseria as well as Veillonella parvula. Some bacterial species of the oral flora such as Streptococcus mutans are also responsible for the development of caries. They are referred to as cariogenic microorganisms. Fungi such as molds, yeasts or dermatophytes settle only on the surface of the skin and mucous membrane in healthy people. Some Candida species also occur as harmless saprophytes in the human throat region. They could be detected in about 70 percent of all persons examined. The skin and mucous membrane colonizations by the Candida fungi bear the collective name candidiasis. The oral flora is important for the protection of the human oral cavity. Thus, the tissue there is protected by some bacterial species from harmful influences, whereby they support the immune system. The microorganisms are located like a biofilm on the tongue, mucous membranes and teeth. After taking meals, the bacteria take over the first digestive processes. Thus, a healthy oral flora also contributes to a positive process of human digestion. In total, there are about 600 species of bacteria and billions of bacteria in the human oral cavity. Scientists are constantly discovering new subtypes. A healthy oral flora results in less tartar on the teeth. Thus, some species of bacteria clean the teeth together with saliva. In this way, inflammation is also counteracted. Therefore, a healthy oral flora is extremely important for the teeth. The bacteria find excellent conditions for their survival and reproduction in the mouth. These include warm temperatures, optimal humidity, and nutrients from food residues that are well suited for microorganisms. Some types of bacteria have special properties. These include attachment mechanisms, which allow the bacteria to adhere well to the teeth, oral mucosa and tongue.
Diseases and ailments
If there is an imbalance of oral flora, this can have harmful consequences for the oral cavity. Thus, not all types of bacteria that belong to the oral flora are benign. These are primarily the lactobacilli (lactic acid bacteria), the fusobacteria (pus bacilli) and the Streptococcus mutans subspecies. They have a favorable effect on the development of caries and feed mainly on food residues containing sugar. Since the bacteria are mainly found on the teeth, their metabolic products can attack these and the neighboring gums. As a result, caries and periodontitis develop. Other types of bacteria, which are located on the tongue, in turn cause foul-smelling bad breath. Even in a healthy oral flora, these harmful microorganisms are present.For this reason, consistent and regular cleaning of the teeth is important so that the germs cannot cause any damage. It is particularly important to remove the plaque that is on the teeth. Plaque, which is a regular source of bacteria, can only be removed mechanically, as with a toothbrush. In order to effectively reduce the amount of plaque, it also requires the use of small interdental brushes, dental floss and possibly mouth rinses. There are several causes that can throw the oral flora out of balance. These include diet, nicotine consumption, the consumption of alcohol, inadequate oral hygiene and orthodontic treatment. But also the intake of antibiotics or some diseases such as diabetes mellitus (diabetes) and cancer are sometimes responsible for disturbances in the oral flora. Due to the disturbed balance, harmful germs multiply undisturbed. Bite injuries represent another health problem in connection with the oral flora. There is a risk of infection from bites by humans or animals, as harmful microorganisms from the oral flora enter the wound. Deep injuries located near a joint are particularly affected. The annual infection rate from bite wounds varies between 15 and 20 percent. Human bites account for the highest risk, at about 50 percent.
