A periodontal disease is a disease of the supporting tissues of the teeth. The main cause of these disorders is dental plaque. In addition, other factors can influence the severity and course. Two disorders play a role in periodontal abnormalities, namely periodontal inflammation and periodontal degradation.
First we discuss the environmental factors that can cause a deviation. These are the local or exogenous (from outside the body) factors. Next, we discuss the factors that come from the body and that can influence the development of periodontitis. These are called system factors or endogenous factors.
Local or exogenous factors
Dental plaque is the most important cause of the development of periodontal abnormalities and caries. The dental plaque is a soft, sticky layer that deposits on the teeth during the day. Dental plaque consists of 70-80% bacteria. In addition, there are leukocytes (white blood cells), macrophages and epithelial cells built into an adhesive. The adhesive is made from sugars by the bacteria in the plaque and in the mouth.
Dental plaque often has the same color as the teeth and is therefore hardly noticeable. Unlike débris or materia alba (loose food residues on the teeth and gingiva), plaque can no longer be removed by vigorous rinsing of the mouth. Plaque can only be removed by mechanical removal with a toothbrush and interdental aids.
When a tooth has been cleaned, a layer of glycoproteins already forms on the surface after a few seconds. We call this layer pellicle. After two hours, bacteria and food residues adhere to this and dental plaque develops. Plaque formation is constantly taking place, with the composition also changing. The older and thicker the plaque, the more anaerobic bacteria settle in it. These are bacteria that do not need oxygen to survive. After fourteen days it is "fully grown", which means that the composition no longer changes. Predilection plates of dental plaque are:
- In pits and fissures of the (pre) molars;
- Cervical along the gingival border;
- On root surfaces;
- Under the edges of overhanging fillings.
In periodontal disease, it is especially the plaque that occurs along the gum line and interdental that is important, because here the bacteria are in contact with the gingiva.
Bacteria in the plaque form toxins. Toxins enter the gingiva via the sulcus and trigger immune responses from the body. This has the result that the periodontal tissue is broken down. As long as the plaque remains in the sulcus, this process will continue.
Nutrition can affect the amount and composition of the plaque formed. On the one hand, certain tough foods, due to heavy chewing, can stimulate the cleansing effect through saliva, lips, tongue and cheeks. On the other hand, food can be sticky, which in turn promotes the formation of plaque. Dental plaque formation takes place in everyone. Yet there are differences between people in the bacterial composition and the speed with which plaque is formed. This appears to have an influence on the origin and course of the periodontal degradation.
If plaque is not removed regularly or not properly, calcification of the plaque can occur under the influence of saliva. This is called tartar. Tartar deposits on dental elements, crowns and bridges, prostheses and orthodontic equipment.
A distinction is made between saliva or supragingival tartar and serum or subgingival tartar. The speed at which tartar is formed is highly dependent on oral hygiene, but differs individually.
Supragingival or salivary tartar is above the gingiva, is usually white or yellow in color, brittle and easy to remove, because the adhesion to the tooth surface is low. The saliva contains minerals that are necessary for the creation of tartar. Most deposits of supragingival tartar take place at the exits of the salivary glands:
- Lingual of the lower incisions (exits of the glandulae submandibulares and sublinguales);
- Buccal of the first upper molars (exit from the parotis glandula, the ear salivary gland) (See image below).
Subgingival or serum tartar is tartar that is under the gums. It is hard and brown-black in color, adheres strongly to the surface of the elements and is difficult to remove. The deposition is a slow process that occurs everywhere in the mouth; there are no preferred places. Minerals that cause subgingival tartar come from the fluid present in the sulcus.
Tartar itself does not or hardly have a damaging effect on elements and supporting tissues. It does, however, increase the retention options for plaque. This can lead to tissue changes (see image below).
Micro-organisms play an important role in periodontal abnormalities. Many different types of bacteria are naturally present in the oral cavity (mouth flora). Various bacteria have been shown to have a clear influence on the development and course of a periodontal disease. We mention a few here.
- Streptococcus sanguinis is important because it adheres to the pellicle on the elements and can produce polysaccharides from sucrose.
- Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia (abbreviated to Aa, Pg and Pi, respectively) and spirochetes may play a role in the development and course of periodontal disease.
The composition of the mouth flora differs between people.
Certain habits can cause a chronic abnormality of the periodontium. As soon as the habit is stopped, the abnormality disappears, provided that the person in question is healthy. Examples of these habits are grinding teeth, nail biting, certain professional habits (eg tailors bite off a thread) or cracking nuts and opening bottles with the teeth. This also includes overloading the periodontium due to incorrect occlusion and articulation. Certain irritants, such as heavy smoking and the use of chewing tobacco, can also influence paradontal disorders
Mouth breathing is counted among the traumatic habits. This is often caused by poor patency of the nose or by the position of the front elements. Mouth breathing is often accompanied by chronic marginal gingivitis of the upper front. The surface of the gingiva dries out and therefore the resistance of the fabric is reduced. Mouth breathing itself does not cause periodontal problems; this is only the case in combination with poor oral hygiene.
Other factors that promote the retention of dental plaque are:
- Overhanging restorations;
- Bad or no contact points between elements;
- Deepened pockets;
- Accessible or fully accessible root splits (furcations, which may result in food penetration (see image below).
Endogenous or system factors
In addition to the exogenous factors, there are factors in the body that can influence the development of periodontal problems. We call these the endogenous or system factors. These endogenous factors can aggravate periodontal disease. Because the resistance of the periodontal tissues is changed by the general factors, they become more susceptible to irritating influences. Examples of system factors are:
- Poor general physical condition;
- Altered hormonal status (pregnancy);
- Specific diseases (diabetes, leukemia, AIDS, cardiovascular disease);
- Psychological factors (chronic stress);
- Nutritional factors;
- Use of medication (eg diphantoin in epilepsy).
Endogenous factors cannot in themselves cause periodontal abnormalities. Only if there is insufficient oral hygiene and therefore plaque accumulation can already existing periodontal abnormalities worsen (see image below).