Fracture of the lower jaw: causes, symptoms, diagnosis, treatment

In peacetime, the frequency of damage to the face is 0.3 cases per 1000 people, and the proportion of maxillofacial trauma among all injuries with bone damage in the urban population ranges from 3.2 to 8%. In this case, facial bones fractures are observed in 88.2%, soft tissue injuries in 9.9%, and face burns in 1.9% of cases.

The number of patients with face injuries in peacetime is from 11 to 25% among all hospitalized in the maxillofacial clinic, with damage to the bones of the face accounting for about 15.2% of all bone fractures.

The most common are isolated fractures of the mandible (79.7%), the second place is occupied by the fractures of the maxilla (9.2%), followed by fractures of the bones of the nose (4.6%), followed by fractures of the zygomatic bones and zygomatic arches (4.1%), 2.4% of cases are fractures of both jaws. Among patients with fractures of the jaw, 83.7% were persons with isolated injuries of the mandible, 8% of the maxilla, and 8.3% of the injuries suffered injuries to both jaws.

What causes a jaw fracture?

In peacetime, the causes of fractures of the jaws are most often the blows and bruises obtained from falling, squeezing (industrial trauma), fights, etc. Often jaw fractures occur in road accidents. In rural areas, jaw fractures can occur as a result of a horse's hoof, the handle of an "old" tractor, and so on.

Relatively rare are gunshot jaw fractures, which are usually the result of improper handling of weapons (more often hunting), children's pranks, etc. In recent years, intentional gunshot wounds of a person by intruders have increased.

Among the causes of injuries of the upper jaw is also dominated by domestic trauma, although to a somewhat lesser extent.

Sometimes there are "medical" injuries of the upper jaw in the form of perforation of the bottom of the maxillary sinuses, arising during the extraction of teeth (usually large or small molars).

Combined injuries of the upper and lower jaws and other areas of the body account for 14% of the total number of combined mechanical injuries. Most often they are caused by road accidents (52%), falling from height (25%), household injuries (17%). Industrial injuries account for only 4%, casual gunshot wounds - 1.3%, other causes - 0.7% of cases.

The prevalence of injuries in the maxillofacial area in men compared with women (8: 1, 9: 1) is explained by their greater employment in industrial and agricultural production, transport, and alcohol abuse (13.6-27.3% of cases).

Damage to the bones of the face is most often observed in the summer-autumn months, coinciding with the period of holidays, tourism, and less often - in winter.

Symptoms of a fracture of the lower jaw

Symptoms of fracture of the lower jaw depend on the degree of displacement of fragments, the number of fractures of the jaw, the presence or absence of a concussion or bruise of the brain, damage to the soft tissues of the face and oral cavity, the presence of damage to other bones of the face, skull base,

It should be noted that in the blood of the victims rough biochemical disorders occur immediately after the trauma; the content of ATP, aluminum, titanium, transferrin, activity of ceruloplasmin, alkaline phosphatase, total lactate dehydrogenase increases in proportion to the severity of the fracture and, consequently, the general condition of the patient (VP Korobov et al., 1989). All these and other circumstances (age, background diseases) explain the fact that in most patients the fractures of the lower jaw are characterized by a significant severity of the clinical course, especially when the integrity of the bone is violated in two, three or more places, brain concussion, rupture and crushing of the maxillary maxillary tissues. Therefore, it is necessary to carefully and thoroughly collect an anamnesis (from the words of the patient or an accompanying person), using all available documents: a certificate, an extract from the medical history , a direction, an act on an accident at work.

In single fractures of the lower jaw, patients complain of a feeling of pain that appeared immediately after the injury, the inability to close the teeth, the difficulty of talking, the violation of the act of chewing, the disappearance of the surface sensitivity of the facial skin and the oral mucosa. With more severe injuries (double, triple, multiple), complaints of difficulty swallowing, especially in the position on the back, and even breathing, are attached.

Collecting an anamnesis from a victim who is in a state of intoxication should take into account possible inaccuracies (intentional or unintentional) regarding the time, circumstances of the trauma, the duration of loss of consciousness, etc. It should be remembered that for the subsequent work of the representative of the investigative authorities in the medical history should be recorded the following information: the exact time of injury; the surname, name, patronymic of the injured and witnesses to this; where, when, by whom, first aid and nature were rendered; what medicines the victim took inside, subcutaneously or intramuscularly, and so on.

When a patient with a complicated trauma enters the hospital (osteomyelitis, sinusitis, suppurative hematoma, phlegmon, pneumonia, etc.), it is necessary to find out when the complication arose, what measures against him were used, where and by whom; while the doctor must observe deontological delicacy, especially when examining a severe patient with a high body temperature, difficulty breathing, speech, etc. Collect an anamnesis should be as quickly as possible in order to prevent the deterioration of the patient and not miss the time necessary to take effective measures against complications.

Symptoms of a fracture of the lower jaw:

1. asymmetry of the face due to soft tissue edema or hemorrhage in the area of the proposed fracture;
2. tenderness in the palpation of the bone;
3. as a rule, to a more or less pronounced displacement and mobility of fragments (with careful bimanual examination);
4. malocclusion;
5. increased electrical excitability of teeth.

If the patient has injuries not only to the jaw and face, but also to other organs, the examination should be carried out in conjunction with the necessary specialists (otolaryngologist, ophthalmologist, neurologist, therapist, etc.) in order to minimize the time of examination to the necessary skilled care. Inspection, palpation, sounding of wounds and wound fistulas should be performed in the dressing room, strictly observing the requirements of aseptic and antiseptic and trying to spare the patient as much as possible.

Inspection allows you to determine:

1. the nature of the asymmetry of the face - due to damage to bones and soft tissues, hematoma, infiltration or edema (the boundaries of which, as well as the violation of bite should be clearly described in the medical history);
2. presence of ruptures of the mucosa of the gums, tongue, and bottom of the mouth;
3. congestion of blood clots in the face, mouth, nasal passages;
4. the outflow of cerebrospinal fluid from the ears and nose.

With the help of palpation, you can find out the cause of the asymmetry of the face (swelling, bone fragments displacement, infiltration, phlegmon, abscess, emphysema). To detect a fracture of the lower jaw allows the next palpatory procedure: the thumb of the right hand of the doctor should cover the right half of the body of the lower jaw, and the index finger - the left one; with a slight pressure on the chin, there is pain in the area of fracture of the body, angle or branch of the lower jaw. Entering the index fingers into the external auditory passages of the patient (by palm surface of the distal phalanges forward) and asking the patient to open and close his mouth or move the chin to the left and right, the doctor can determine the degree and symmetry of mobility of the lower jaw heads. If one of them under the finger is not probed, this indicates an anterior dislocation of the lower jaw, or a fracture-dislocation of the condylar process. With bilateral dislocation of the head of the lower jaw is not probed on both sides.

Data obtained from an objective examination of the patient (examination, palpation, tonometry, thermometry, determination of the pulse rate, auscultation, percussion, etc.) are entered in the medical history. Having established a preliminary diagnosis, the doctor prescribes additional studies (if necessary) and treatment.

Since fractures of the lower jaw are often combined with a concussion of the brain or a bruise of its severe or mild degree, every patient with a fracture of the lower jaw should consult a neurologist.

When examining a patient with a trauma in the maxillofacial area, attention should be paid to the state of the pulse, the amount of blood pressure. To suspect craniocereberal trauma in these cases allows the presence of such symptoms as a disturbance of consciousness, amnesia, headache, dizziness, nausea and vomiting.

In addition, patients with fractures of the lower jaw often have traumatic neuritis of the trigeminal nerve branches, which is caused by degenerative changes in nerve fibers and is characterized by paresthesia, hyper- or anesthesia of the teeth, lower lip, etc.

In the long-term traumatic neuritis often leads to the destruction of bone in the fracture zone, and in remote areas from it. Therefore, timely detection (neurological and electro-odonto-diagnostic methods of investigation) and treatment of neurological disorders are of great importance.

It is equally important to determine the sensitivity of microflora to antibiotics when the fracture is open , since all fractures of the lower jaw within the lower dental arch are infected with the pathogenic microflora of the oral cavity, mainly staphylococci and streptococci, which in half of the patients are resistant to bacteriostatic drugs.

Classification of fractures of the lower jaw

Non-fire fractures of the lower jaw can be opened outward and into the oral cavity. Fractures localized within the dental arch are usually open in the mouth as a result of a gum rupture that fits snugly to the alveolar process. They can also be closed, especially if they are localized within the mandibular branch.

Allocate the following types of fractures: complete and incomplete (fracture); single, double and multiple; one- and two-sided; linear and comminuted; with the presence of teeth on the fragments and in the absence of teeth. Non-fire fractures are almost never accompanied by the formation of a bone substance defect.

According to the literature and our clinic, fractures of the lower jaw most often occur in the area of its angles (57-65%), condylar processes (21-24%), small molars and canines (16-18%), large molars (14 -15%) and most rarely in the area of incisors.

In practice, a fracture of the lower jaw can occur in any part of it, so a schematic representation of the predominant localization of fractures of the lower jaw in the angle and chin holes, as well as other places of "least resistance", is conditional.

The significant incidence of fractures in the condylar processes and mandibular angles can be explained by the prevalence of the current trauma at the present time, in which the impact mainly falls on the chin and the angles of the lower jaw, i.e. In the antero-posterior and lateral directions. The lower jaw is a flat bone, however, it is impossible to talk about the presence of places of least resistance of its individual parts only on the basis of the anatomical structure, not taking into account the direction and place of application of the traumatic force.

The lower jaw has the shape of an arch; in the region of angles, large molars, branches and bases of condylar processes, its cross section is very thin, and in the antero-posterior direction the section of these sections is almost 3 times larger. Therefore, with lateral impacts, a fracture of the mandible in these places is possible, and as a result of applying a relatively small force, and with lateral impacts in the region of the angle, the wisdom tooth weakens the resistance of this part of the bone, and, when striking, from front to back, increases its strength, "working "On the contraction.

The area of the canine is the place of the least resistance of the lower jaw only with lateral impacts, because because of the considerable length of the root, the mass of bone substance here is reduced, especially from the lingual and vestibular sides.

In front-back attacks, the canine tooth, like the wisdom tooth, "working" on compression, increases the strength of the bone and exerts a resistance to the mechanical force of the impact.

The region of the upper part of the condylar process, the cross section of which is wider than in the antero-posterior part, is the place of weak resistance to shocks directed from front to back. In lateral attacks, fractures here are very rare; they are usually localized at the base of the condylar process and have an oblique direction: from top to bottom and from the inside outwards, that is, they correspond to the structure and direction of the cortical layers of this region.

Thus, to the anteroposterior impacts and lateral impacts, the condylar processes (base and neck area) are least resistant, the corners of the lower jaw and the socket of 83/38 teeth.

With an industrial trauma, the traumatized object moves at a much higher speed than with the household one. Therefore, the lower jaw is damaged directly in the place of application of the acting force, and the rest of its sections do not undergo significant deformations due to inertia, fracture or compression. Because of this, production fractures are usually straight with a fragmentation of the jaw. If the traumatic effect is relatively slow (compression of the jaw), the fracture occurs as in the case of domestic trauma, i.e., not only at the site of application of force, but also in remote areas, even on the opposite side (reflected fractures).

Traumatic (household or other etiology) fracture of the lower jaw sometimes occurs in areas with reduced strength due to bone destruction by the above pathological processes; fractures in the zone, for example, of the radicular cyst can be either linear or fragmented.

It is very important to find out whether the fracture of the lower jaw is single or multiple, since multiple fractures (double, triple, etc.) are particularly difficult to treat. Single fractures occur in 46.7%, double fractures in 45.6% (in the overwhelming majority - one fracture on the right and left), triplicates in 4.7%, multiple fractures in 2.1% of the affected; isolated fractures of the alveolar process are 0.9% of the cases. As for the victims with combined injuries of the face, jaws and other areas of the body, among them, individuals with fractures of the lower jaw are only 12.7%, upper jaws - 10.3%, both jaws - 4.5%, zygomatic bones - 12.4%, bones of the nose - 4.8 %, but only soft tissues of the face, teeth, tongue - 55.3%.

Single fractures of the lower jaw are usually localized between the 7th and 8th teeth, in the region of corners, condylar processes, between the 2nd and 3rd teeth.

Double fractures are most common in the canine and condylar processes, the canine and the angle of the lower jaw, small molars and the angle of the lower jaw.

Triple fractures are more often localized in the region of both condylar processes and in the region of the canine or both condylar processes and between the central incisors.

[1], [2]

Diagnosis of fracture of the lower jaw

Diagnosis is based on the location of the fracture and the nature of the displacement of fragments; the displacement depends on the degree of imbalance in the thrust of the masticatory muscles, the direction of the fracture, the number of teeth left on the jaw fragments, and other factors.

To clarify the diagnosis of a fracture of the lower jaw, it is necessary to perform radiography in two projections (anterior-posterior and lateral) or orthopantomography. This examination is especially important for fractures of condylar processes, branches and angles of the lower jaw, since fractures of this localization occur in every second or third victim and are often poorly contoured on radiographs, overlapping the cervical vertebrae, the mandibular branch and the skull base bone .

In many cases of condylar fractures, the correct diagnosis is established only after radiographic examination of the patient; while the higher the fracture line on the process, the more indicative the layered radiography is.

To clarify the nature of the fracture and the disease of the condylar process of the lower jaw, it is very useful to apply computer tomography on the CPT-100 apparatus (EN Ryabokon, 1997), to visualize the temporomandibular joint on the MRI imager Obraz-1 (manufactured by the NGO "Unit").

In isolated lesions of the alveolar process, only limited areas of the dental arch are displaced, which is well identified by intraoral radiography.

When establishing the diagnosis of a "jaw fracture", it is necessary to accurately determine its localization, character (linear, comminuted), the presence or absence of displacement of bone fragments. It is unacceptable, for example, to formulate the diagnosis as: "fracture of the body of the lower jaw to the right", "central fracture of the lower jaw", "fracture of the upper jaw", etc. Diagnosis always determines the method of treatment. Some of the term "central fracture" is understood as a fracture between the central incisors, and others - a fracture within the four incisors. Where does the body of the jaw begin and where does it end? According to the anatomy data, the jaw's body is all of its horizontal part from the left to the right angle. And some authors believe that the body of the jaw starts from the canine and ends at the tooth of wisdom. As for fractures in the jaw of the jaw, they are often called central fractures.

Depending on the location, these types of fractures should be identified.

1. median - passing between the central incisors;
2. incisive - between the first and lateral incisor;
3. canine - passing along the line of the canine;
4. mental - passing at the level of the chin opening;
5. the body of the jaw - most often within the wells of the 5th, 6th, 7th teeth and the medial margin of the socket of the 8th tooth;
6. angular, or angular, that is, passing behind or near the socket of the lower 8th tooth, i.e. Within the lower third of the jaw branch;
7. jaw branches - within its middle and upper thirds;
8. bases of the condylar process;
9. cervical, or cervical, passing in the region of the neck of the condylar process of the lower jaw;
10. fracture-dislocation - a combination of a fractured condylar process with a dislocation of the head of the lower jaw;
11. Coronary - in the region of the coronoid process of the lower jaw.

Calling the fracture of the lower jaw, in parentheses it is necessary to specify its localization by the conventional designation of the tooth, in the hole of which it passes, or the teeth between which the fracture is localized.

[3], [4], [5], [6]