X-ray signs of caries, pulpitis, periodontitis, periodontal disease

Roentgenodiagnosis of caries, pulpitis, periodontitis, periodontal diseases

Roentgenodiagnosis of caries

Caries is a pathological process, manifested by demineralization and progressive destruction of hard tooth tissues with the formation of a defect. This is the most common disease of the teeth: the caries affects population by 100%. In erupting teeth, depending on the location, caries fissure, cervical, on the contact (approximate), vestibular and lingual surfaces are distinguished. In molars caries often develops on the masticatory surface, incisors, canines and premolars - on contact surfaces.

Depending on the depth of the lesion, the stage of a spot (carious stain), superficial, middle and deep caries are distinguished. With simple or uncomplicated caries, there are no changes in the pulp. Complicated caries is accompanied by the development of inflammation in the pulp (pulpitis) and periodontitis (periodontitis).

Caries can be affected by individual teeth, multiple teeth (multiple caries) or almost all teeth (systemic damage). Multiple caries can be manifested in the form of a so-called circular and surface caries, which propagates predominantly over the surface. At clinical research it is not possible to diagnose small carious cavities and carious lesions, inaccessible for direct examination. Only a combination of clinical and radiographic research ensures the detection of all carious cavities.

Objectives of X-ray study in caries:

1. Identification of carious cavity and determination of its dimensions, including depth;
2. the establishment of its relationship with the cavity of the tooth;
3. evaluation of periodontal conditions;
4. diagnostics of secondary caries under seals and crowns;
5. control the correctness of cavity formation;
6. assessment of the application of the treatment pad and its adherence to the walls;
7. detection of overhanging or merging seals.

Only carious lesions are radioliologically recognized, in which hard tooth tissues lose at least 1/3 of the mineral composition. The radiological picture of the carious cavity depends on its size and localization.

The shape and contours of carious cavities are variable, which is due to the peculiarities of the spreading of the carious process. When a carious defect is projected onto an unchanged tooth tissue (caries on the vestibular, lingual and masticatory surfaces), it is presented as a rounded, oval, irregular or linear shape of the enlightenment area. The edge-forming carious cavities (located in the approximal, cervical areas and along the incisal edge of the incisors and canines) emerging on the contour change the shape of the crown.

The clarity or fuzziness of the contours of the cavity is determined by the peculiarities of the carious process. On the contact surfaces carious cavities are revealed especially clearly and at certain stages of development in form resemble the letter V, the vertex of which is facing the enamel-dentine border.

There are difficulties in the distinctive recognition of small cervical caries cavities from a variant of the anatomical structure, when there are depressions caused by the absence of enamel in these areas. The sounding of the gingival pocket allows you to overcome the difficulties encountered.

Small carious cavities on the chewing, vestibular or lingual surface of the tooth overlap with unaltered solid tissues of the tooth and do not find reflection on the roentgenogram.

Carious cavities are well recognized clinically, and to X-ray examination in most cases resorted to the diagnosis of hidden carious cavities, inaccessible for visual inspection and instrumental research. These include carious cavities at the root, under seals (secondary caries), crowns and on contact surfaces.

X-ray examination in most cases makes it possible to estimate the depth of spread of the carious process. The stage of the spot is not radioliologically determined. With superficial caries, especially in cases where the cavity is a backbone, a defect is visible within the enamel. With medium and deep caries, dentin is involved in the process to some extent. In view of the slower spread of the process in the enamel on the roentgenogram, a discrepancy between the dimensions of the cavity in the enamel and the dentin is sometimes determined.

Difficulties that arise in determining the relationship between the carious cavity and the cavity of the tooth are due to the location, depth of the carious focus and the features of the projection. On the radiographs executed in compliance with the "bisector rule", the tooth cavity is projectively reduced in height. With average caries, the deformation and decrease of the tooth cavity also occur as a result of the deposition of secondary dentin. The carious focus on the vestibular and lingual surfaces of the tooth is sometimes projected onto the cavity of the tooth. When the carious cavity is located on the masticatory and contact surfaces, the X-ray study makes it possible to estimate quite clearly the thickness of the dentin layer separating the carious focus from the tooth cavity.

Secondary caries under the seal is presented in the form of a defect of various sizes, a band of enlightenment appears between the filling and the dentin. A similar picture takes place when sealed using pads that do not absorb X-rays. Uneven, fuzzy, undermined contours of the cavity indicate secondary caries. A comparison with an X-ray taken before the filling can help in the diagnosis.

X-ray examination allows you to assess how the cavity is formed, the quality of sealing, the fit of the filling material to the walls, the overhang of the seal between the teeth and in the gingival pocket.

Fillings from amalgam and phosphate-containing filling materials are defined as a high-intensity shadow on the background of tooth tissues. Fillings made of silicate cement, epoxy material and plastics are X-ray negative, therefore, the prepared cavity and the linear shadow of the gasket adjacent to the walls are visible in the photograph.

In children, caries occurs even in the stage of teething. The highest frequency of its development is observed at the age of 7-8 years and after 13 years. On the milk teeth, caries affects mainly the contact surfaces, is characterized by rapid progression of the process and complications in the form of pulpitis and periodontitis.

Multiple caries of infant teeth, due to metabolic disorders, are sometimes localized symmetrically on the teeth of the same name. Changes in hard tissues of the tooth also occur in non-carious lesions: hypoplasia, fluorosis, wedge-shaped defects, pathological erosion.

The wedge-shaped defect is located on the vestibular surface of the crowns in the region of the necks. On the roentgenogram is determined in the form of lumen strips in the cervical region, which run parallel to the cutting edge.

Pathological abrasion can be caused by bad habits (holding in the mouth of foreign objects - nails, mouthpiece of the tube). When erasing, a dentin can be formed, causing a decrease in the height of the tooth cavity. In the region of the apexes of the teeth, the secondary cement is stratified (a picture of hypercementosis).

Spotted defects in fluorosis, as a rule, do not find reflection on radiographs.

Common in the dental practice, the X-ray examination method with the ray centering on the tip of the tooth in connection with the resulting projection distortions is the least effective in diagnosing caries. The interproximal technique, which excludes the projection of the contact surfaces of adjacent teeth, is more effective. The future in this respect is for radiography with a parallel beam of rays from a large focal length, in which the size and shape of the crown are not distorted. On direct panoramic radiographs, premolars and molars crowns are superimposed, this does not occur on orthopantomograms, but difficulties arise in assessing the condition of the front teeth.

Radiation injuries of teeth

According to G.M. Barer, 4 months after the remote gamma-therapy of malignant tumors of the maxillofacial region, destruction of hard tissues of teeth included in the volume of irradiation was observed in 58.4% of cases. There are cervical and multiple foci of crown destruction, intensive erasure of cutting and chewing surfaces occurs. There is a higher incidence of lower incisors and canines. Features of the clinical manifestation and the nature of the flow make it possible to identify radiation lesions of the teeth as an independent nosological unit.

Among the etiological factors, there is an effect of hyposalization, changes in the crystal lattice, denaturation and demineralization of enamel, dentin and cement.

X-ray diagnosis of pulpal diseases

The inflammatory process in the pulp usually does not cause changes in hard tissues that limit the tooth cavity and root canals, and does not have direct radiographic signs.

An indirect sign of pulpitis is the deep carious cavity defined on the roentgenogram, communicating with the cavity of the tooth. However, the final diagnosis of pulpitis is established only on the basis of a complex of clinical data, the results of sounding and the determination of the electroexcitability of the pulp.

Dystrophic processes in the pulp can lead to the formation of denticles, located at the walls of the cavity of the tooth and the root canal (parietal denticles) or freely in the pulp (free denticles). On the roentgenogram, denticles are defined as rounded single or multiple dense shadows against the background of the tooth cavity or root canal.

Sometimes there are pains of a neuralgic nature due to infringement of the nerve fibers of the pulp with denticles. In these cases, the diagnosis is established only after performing an X-ray study.

With chronic granulomatous pulpitis, an "internal granuloma" can develop, causing destruction of the tooth adjacent to the dentin cavity. This lesion is more common on the front teeth. On the roentgenogram, a clearly defined, rounded, round-shaped bleaching is defined, projecting onto the tooth cavity. There are difficulties with distinctive recognition with caries on the lingual or buccal surface of the tooth. Internal granuloma can be complicated by a pathological fracture of the tooth.

X-ray diagnostics of periodontitis

In order to diagnose periodontitis, intraoral contact radiographs are widely used, performed according to the rules of isometric projection. To assess the relationship between the roots and the bottom of the maxillary sinus, panoramic lateral radiographs and orthopantomograms are produced, and in the absence of special equipment, we developed extraoral contact radiographs in an oblique projection.

Acute apical periodontitis. Despite the pronounced clinical picture, an insignificant expansion of the periodontal cleft at the apex of the root, caused by periodontal inflammation, is usually not possible to detect radiographically. Diagnosis of acute periodontitis is established practically on the basis of clinical data. Acute process, lasting from 2-3 days to 2 weeks, can go to chronic.

Chronic granulating periodontitis. The morphological process is characterized by proliferation of granulation tissue, which causes intensive resorption of hard tooth tissues (cement, dentin), cortical plate of the wall of the dental alveolus and spongy bone tissue. On the roentgenogram, the normal image of the periodontal cleft at the apex of the affected root is absent, the compact plate of the dental alveolus is destroyed. At the apex of the root, a lesion of bone tissue of irregular shape with uneven fuzzy contours is determined. As a result of resorption of cement and dentin, the surface of the root that emerges on the contour is eroded, sometimes the root of the tooth becomes shorter.

Chronic granulomatous periodontitis. Depending on the morphological features of granulomatous periodontitis, the tooth granuloma, complex dental granuloma and cystogranuloma are isolated. In a complex granuloma, along with the granulation tissue, epithelial strands proliferate, and it becomes a cystogranulum. As a result of degeneration and decay of the epithelium, a cavity is formed, lined with epithelium from within. On the roentgenogram at the tip of the tooth, the focus of enlightenment is rounded or oval with clear, even, sometimes sclerotized contours. Cortical plate of the hole in this area is destroyed. Occasionally, hypercementesis develops and the apex acquires a clavate shape. Radiographically distinguish a simple granuloma from cystogranuloma is not possible. However, it is believed that with the size of the lesion site more than 1 cm, the presence of cystogranuloma is more likely.

Chronic fibrous periodontitis. This kind of periodontitis arises as the outcome of acute or other chronic forms of periodontitis; can also develop with prolonged traumatic effects on the tooth. In this case, as a result of productive reactions, periodontium is replaced by coarse-fibrous structures of ruby tissue; there is a thickening of periodontal, excessive formation of cement (hypercement) in the region of the apex or along the entire surface of the tooth.

On the roentgenogram, the extension of the periodontal cleft is determined at the apex of the root. A compact plate of the dental alveoli is preserved, sometimes sclerosed. The root at the apex is clavate thickened due to hypercementosis.

When projecting some anatomical formations to the top of the root (incisors and chin holes, large bone cells), difficulties arise with distinctive recognition. The integrity of the terminal cortical plate of the socket makes it possible to exclude the diagnosis of chronic granulomatous and granulating periodontitis. In radiography with a change in the course of the central beam of rays, as a rule, the anatomical formations in these photographs are projected separately from the apex of the root.

Chronic low-level inflammatory processes can cause excessive production of bone tissue with the formation of small lesions of sclerosis. More often it is observed in the roots of the lower molars. When analyzing images, difficulties arise in the differentiation of these foci with small osteomas or fragments of the root.

Diagnosis of chronic periodontitis in the acute stage is established on the basis of clinical manifestations of acute periodontitis and an x-ray picture of chronic periodontitis (granulating or granulomatous). Chronic fibrous periodontitis in the stage of exacerbation is sometimes regarded as acute periodontitis.

The fistula, located parallel to the long axis of the root, is visible on the roentgenogram in the form of a narrow band of enlightenment from the apical center of destruction to the alveolar margin of the jaw. In the other direction, the fistula in the picture is usually not visible.

Repeated radiographs are most often performed during treatment with a needle to determine the patency and in the end - to assess the quality of root canal filling. After the mechanical and chemical treatment of the root canals, root needles are introduced into them and an X-ray is made to evaluate the patency of the canal. On the roentgenogram, insufficient opening of the tooth cavity, canopies, in particular over the mouth of the root canal, thinning and perforation of the walls of the cavity, root, bottom, the presence of a fragment of the instrument in the channel is determined. Gutta-percha pins are clearly visible in the channels. To identify the perforation, X-rays with the inserted root needle are performed. The false course is better seen with its medial-lateral direction, worse - with the cheek-lingual. An indirect sign of perforation is the destruction of the cortical plate adjacent to it.

To determine changes in the size of periapical foci after treatment, it is necessary to perform repeated identical radiographs that exclude projective distortions. The identity of the shots of the frontal teeth is ensured by performing direct panoramic radiographs in compliance with standard research conditions (the position of the patient and the tube in the oral cavity). For the study of premolars and molars, lateral panoramic radiographs and orthopantomograms are performed. Complete or partial restoration of bone tissue in most patients occurs within the first 8 - 1 2 months after treatment.

With inadequate filling of the root canal, exacerbation of chronic periodontitis is possible. In these cases, the radiograph is needed to assess the extent of the canal filling and the nature of the filling material.

X-ray diagnostics of chronic periodontitis in children. In small children, even average caries can be complicated by chronic periodontitis. There is mainly primary-chronic granulating periodontitis, localized in molars in the bifurcation region.

In connection with the proximity of the rudiments of permanent teeth, especially in molars, a number of complications may arise:

1. death of the follicle due to the germination of the granulation tissue into the growth zone;
2. violation of calcification of enamel due to penetration of the infection into the follicle;
3. displacement of the rudiments of permanent teeth;
4. acceleration of the eruption of the permanent tooth;
5. development of the follicular cyst.

In children with chronic periodontitis of lower molars on panoramic radiographs, ossified periostitis is sometimes detected in the form of a linear shadow parallel to the cortical layer along the lower edge.

In children and adolescents, the growth zone in the region of unformed apex should not be confused with granuloma. In the growth zone, a periodontal slit of uniform width, a compact plate of the socket is not broken, the tooth has a wide root canal.

X-ray diagnostics of periodontal diseases

A complex of periodontal tissues - the periodontium includes a circular ligament of the tooth, gum, bone tissue of the alveoli and periodontium.

In the study of periodontal preference is given to panoramic tomography and interproximal images. Under the standard conditions of the study, the techniques ensure the performance of identical images, which are necessary, in particular, for evaluating the effectiveness of the treatment measures. Informative and panoramic radiographs, the performance of which, however, is associated with high radiation load.

Intraoral contact radiographs, produced with observance of the isometric rules, create a false impression of the state of the cortical closure plate, because the buccal and lingual divisions are projected separately. The implementation of contact radiographs in the dynamics sometimes leads to an incorrect evaluation of the treatment measures.

The first radiologic symptoms of changes in the interalveolar septa are not early, so radiographic examination can not be a preclinical diagnostic measure.

Gingivitis. There are no changes in the interdental partitions. With ulcerative necrotic gingivitis in children and adolescents on the roentgenogram, the widening of the margins of the periodontal gap and the osteoporosis of the vertices of the cortical plates of the interalveolar septa are determined.

Periodontitis. When periodontal lesions occur in the area of one or more teeth, limited, or local, periodontitis is diagnosed, with the involvement of the periodontium of all the teeth of one jaw or both jaws - diffuse periodontitis.

Local periodontitis. Local periodontitis is characterized by the destruction of the interdental septum of one degree or another. On the roentgenogram, as a rule, the cause of its appearance is visible: "overhanging" seals, improperly made artificial crowns, foreign bodies, large marginal carious cavities, subgingival deposits. The depth of the periodontal pocket reaches 3-4 mm.

The main symptoms of diffuse generalized periodontitis are osteoporosis and a decrease in the height of the interdental septa. Depending on their severity, the following degrees (stages) are radically differentiated:

• initial - cortical closing plates of vertices of interdental septa absent, osteoporosis of interdental septum without decrease in height;
• I - decrease in the height of the interdental partitions by 1/5 of the root length;
• II - the height of the interdental septum is reduced by 1/2 the length of the root;
• III - the height of the interdental partitions is reduced by 1/3 of the length of the root.

The spread of inflammation to the periodontium radiographically manifests itself in the form of an extension of the periodontal gap in the marginal regions. With the complete destruction of the cortical plate of the socket around the root, a spongy bone with a uneven contour is visible.

Different groups of teeth of the same patient show a decrease in the height of the entire interalveolar septum (horizontal type) or destruction of the septum in one tooth, while a decrease in its height in the neighboring tooth is not so significant (vertical type).

The severity of destructive changes in the margins of the alveolar processes and the degree of mobility of the teeth are not always comparable. In this case, the ratio between the size of the root and the crown is important: teeth with long roots and multi-rooted teeth with divergent roots retain stability for a long time even with pronounced bone changes.

The repeated radiographs allow us to judge the activity of the flow or the stabilization of the process. The appearance of the sharpness of the contours of the marginal parts of the alveolar processes, the stabilization of osteoporosis or the normalization of the radiographic picture indicate a favorable course of the process.

In diabetics, changes in the margins are similar to those observed with periodontitis.

Paradontosis. With paradontosis, there is a sclerotic reconstruction of the bone pattern - the bone marrow spaces become smaller, individual bone beams thicken, the pattern acquires a shallow character. The elderly street is similarly restructured in other parts of the skeleton.

The degree of decrease in the height of the interdental septum is the same as for parodontitis. In case of joining the inflammatory process on the roentgenogram, signs of periodontitis and periodontitis are revealed.

Parodontolysis develops with a rare genetically inherited disease - keratoderma (Papillon-Lefevre syndrome). Progressive resorption of the marginal parts of the alveolar process leads to loss of teeth. The disease begins during the eruption of milk teeth, causing their loss. Temporary stabilization is replaced by progressive osteolysis of the alveolar process with eruption of permanent teeth.

Histiocytosis the X. Of the three varieties of histiocytosis (eosinophilic granuloma, or Taratynov's disease, Hend-Schüller-Crischen disease and Letterter-Sieve disease), eosinophilic granuloma is most common. The etiology of these diseases is still unknown. It is believed that they are different forms of the same process. Morphological substrates are specific granulomas that cause destruction of the involved bones in the process. The disease proceeds painlessly, sometimes with an increase in body temperature. When the jaw is injured, the X-ray picture sometimes resembles that of parodontitis.

Eosinophilic granuloma most often develops in children and young men (under the age of 20 years), men get sick 6 times more often. Affects mainly flat (skull, pelvis, ribs, vertebrae, jaws) and femurs. Histologically, intraosseous proliferates (granulomas) are detected from histiocytic, plasmocyte cells and eosinophils. In the later stages, xanthomous changes occur with the accumulation of cholesterol and the Charcot-Leiden crystals in the cytoplasm. In the area of the former foci of destruction, with a favorable course of the disease, scar tissue is formed, and sometimes bone.

With an eosinophilic granuloma, as a rule, changes are found not only in the jaws, but also in the flat bones of the cranial vault - rounded, crisp defects, as though punctured. In the jaws, granulomas often occupy a marginal position, involving the upper and lower alveolar processes in the pathological process-teeth that lack bone structure, as it were, hang in the air ("floating teeth"). After the loss of teeth, the wells do not heal for a long time. In children, granulomas located near the periosteum can cause a picture of ossifying periostitis.