Root caries is a pathological destructive process characterized by the destruction of hard tissues of the intraosseous (root) part of the tooth. The disease can be completely asymptomatic or manifest as a cosmetic defect, provoke pain during meals, brushing teeth. Carious root lesion can be suspected already at the stage of examination of the oral cavity and confirmed with the help of thermal tests, instrumental diagnostics (dental x-ray, EDI). The main methods of treatment are filling of the carious focus, remineralizing therapy.
Root caries is widespread on all continents and affects all segments of the population, the incidence of it is almost total ‒ 80-98%. The prevalence of root caries (cement caries) correlates with age and ranges from 4% in patients under 30 years of age to 35-50% in the group over 65 years of age. The lesion is more often detected in persons with impaired dentoalveolar attachment ‒ patients suffering from periodontal diseases, and elderly people with age-related bone atrophy. A particularly aggressive course is observed in those who receive radiation to the head and neck area. Cement caries can occur on any tooth, but molars are more often affected by it.
Modern researchers identify three main conditions that provoke the appearance of a carious focus in the area of the tooth root ‒ the disease develops only in the case of their complex simultaneous exposure. That is, none of these causes alone (in the absence of the other two) is capable of inducing the onset of the pathological process:
Cariesogenic microflora. Among the various kinds of microorganisms colonizing the oral cavity, bacteria dominate. Some of them, for example, Mutans streptococci, actinomycetes and certain types of lactobacilli, produce organic acids from carbohydrates coming from food, which cause the demineralization of cement. This leads to an increase in its permeability, the appearance of a carious focus.
The use of simple carbohydrates. Sucrose has the greatest cariesogenicity, the main source of which is refined sugar. Bacteria break it down by synthesizing acid and glucan, a substance involved in the formation of plaque. Other carbohydrates are also dangerous: for example, fructose and starch. To start producing organic acids, carbohydrates need to stay on the cement surface for a while so that bacterial cells have time to absorb them.
Reduction of caries resistance. This is a deterioration in the resistance of tooth tissues and the body as a whole to the occurrence of a carious process. Many reasons can lead to such a condition: a decrease in the calcium content in the structure of hard root tissues, insufficient salivation, bad habits, etc. There is a decrease in the strength of cement and dentin, the process of natural cleaning of the dental surface with saliva is disrupted.
The likelihood of developing the disease increases in the presence of predisposing factors. The risk of carious lesions of the root zone increases in people over 60 years of age, when bone atrophy and exposure of dental roots occur due to age. Root caries is often exposed to persons with periodontitis, periodontal disease, gum recession, in which there is a violation of dental attachment. The danger increases due to non-compliance with oral hygiene, a decrease in local immunity of the mucous membrane.
When eating foods containing sucrose or other cariesogenic carbohydrates, the microflora of plaque ferments these substances, forming organic acids: pyruvic, lactic, formic, etc. This leads to a violation of the acid-base balance on the surface of the tooth, in particular, in the cervical zone. If the root is exposed, the cement covering it is exposed to acids, which, due to the concentration gradient, penetrate into it and dissociate, causing demineralization.
In the future, the pathology may progress and affect the dentin, causing the appearance of a carious cavity. It is usually filled with food residues, microorganisms, elements of oral fluid and destroyed dental tissues. The dentin lining the walls of the defect is demineralized, infected, its deeper layers are sclerosed, gradually passing into intact tissue.
In the central part of the root of the tooth there is a root canal with vessels and nerves. It is surrounded by dentin, which is covered with cement on the outside. Both of these tissues, consisting of mineral salts and organic compounds in different ratios, can undergo a carious process. Depending on the depth of the lesion in therapeutic dentistry , there are three forms of root caries:
- Initial. It is characterized by partial destruction of cement, but the border with dentin remains. At the same time, a brown or dark spot may appear on the surface of the root.
- Superficial. The cement-dentine joint is destroyed, a shallow brown defect is formed, surrounded by an upper layer of dentine. The depth of the cavity does not exceed 0.5 millimeters.
- Deep. This form is distinguished by the spread of the process to a depth of more than 0.5 millimeters. The carious cavity is separated from the pulp chamber only by a thin layer of dentin.
The process is able to proceed asymptomatically, especially at the initial stage, but it can provoke pain during brushing, taking sour, salty or sweet food, which quickly pass after the stimulus is eliminated. Sometimes hot or cold foods cause unpleasant sensations. If a pathological focus in the form of local darkening of cement is located on the labial surface of the front teeth, the patient complains of unsatisfactory aesthetics. Sometimes the stain practically merges with the surface of the root or hides under plaque or stone.
When the carious process reaches the cement-dentine junction, penetrating into the surface layers of dentine, the cavity becomes deeper, filled with dead tissues, food or dental floss gets stuck in it. Short-term pain is also induced by chemical, temperature and mechanical factors, but may not be present at all. If caries affects the dentin layers bordering the tooth cavity, pain often occurs during hot or cold meals. Otherwise, the symptoms of a deep form of caries are similar to those in its previous stages.
If you do not attempt to treat root caries, the process can reach the tooth cavity and provoke pulpitis. At the same time, the pain can be so unbearable that it becomes impossible to postpone going to the doctor any longer. If you endure a pulse pain, then it can disappear on its own, which indicates the chronization of the process. In the future, the infection is highly likely to provoke inflammation of the connective tissue ligament of the tooth ― periodontitis, and this, in case of untimely treatment for medical help, is fraught with destruction of the underlying bone and loss of the tooth.
The presence of tooth root caries is detected by a dentist-therapist. Diagnosis is carried out in stages at the first clinical appointment. The examination process is aimed at clarifying the patient’s complaints: the presence of pain, its nature and accompanying circumstances. Additionally, various tests and studies are performed:
- Tooth probing. Examination of the dentition is carried out with the help of a dental mirror and a sharp probe. When examining a rapidly progressing carious lesion, its soft or “leathery” consistency and uneven, sharp edges are noted. The surface of the pathological focus at the stage of remission is usually shiny, smooth, hard with smooth, dense edges.
- Temperature tests. To distinguish deep tooth root caries from pulpitis, cold water and heated wax are used. At the same time, pay attention to the duration of pain: if the unpleasant sensations disappear immediately or quickly after the removal of the irritating agent, as a rule, a carious lesion is diagnosed.
- Electrodontometry. With the help of a special device, the condition of the tooth pulp is determined depending on its reaction to an electric current of a certain strength. In the case of root caries, the sensitivity of the dental tissue to the current is in the range of 2-6 µA (sometimes more), with pulpitis ― about 20-90 µA. Indicators over 100 mica cause suspicion of pulp death and the development of periodontitis.
- X-ray examination. The patient is given an intraoral sighting of one or two or three diseased teeth. The size and depth of the hearth are well visualized on it, which makes it possible to assess the integrity of the border between dentin and cement. Special attention is paid to the distance from the bottom of the carious cavity to the pulp chamber.
The treatment regimen is developed based on the stage and speed of the carious process, the number of affected teeth. At the same time, the condition of the entire oral cavity (mucous membrane, bite) and the presence of concomitant pathology in the patient are necessarily taken into account. The main modern techniques used to eliminate root caries include:
- Remineralizing therapy. This method as the only method of treatment is suitable only for the initial stage of the disease. Tooth cement is exposed to local or general preparations with a high content of calcium and fluoride, which eliminate or stabilize the focus of demineralization. Remotherapy as an auxiliary method is also indicated for rapidly progressive caries, when the pathological process affects a large number of teeth in a short period of time.
- Preparation and filling. If the cement-dentine border is damaged, the carious focus is gradually opened under local anesthesia, treated with borons. Then the formed cavity is filled with a seal. In modern medical institutions, polymer-based sealing materials are the most common – light-curing composites.
Patients are often recommended to visit a surgeon and a periodontist to close the exposed root with a gingival flap and treat periodontal diseases. If the cement is protected by gum tissue, bacteria and carbohydrates will not be able to penetrate to its surface. The patient may also be referred to a gastroenterologist or endocrinologist, since gastrointestinal diseases and endocrine disorders are risk factors for carious lesions.
Prognosis and prevention
The prognosis of properly treated tooth root caries can be considered favorable. However, a secondary carious process often occurs around the sealed cavity, the appearance of which depends on the patient’s state of health, his approach to the implementation of oral hygiene. Currently, new filling materials are being developed and clinically tested, which are able to permanently prevent the recurrence of the disease.
In order for sealed and intact teeth to remain healthy for many years, you need to regularly use dental floss, brush your teeth with a paste twice a day after the first and last meal. During the day after eating (especially confectionery products, sweet fruits), it is recommended to rinse your mouth with alkaline mineral water. Also, for 5-10 minutes after eating up to 3-5 times a day, you can use chewing gum without fruit fragrances, if there are no contraindications.