Mandibular fractures.
I/ Introduction: Mandibular fractures characterized by a rupture of the continuity solution of the mandible bone occupy an important place in cases of maxillofacial trauma which are increasingly frequent. They generally affect young subjects, male, most often victims of road accidents or fights.
II/ Anatomy : The mandible is a bone of membranous origin, mobile, unpaired and median. It is a flat and long bone, curved on the flat to form the mental symphysis and on the field to form the angles. These folds constitute areas of weakness.
The mandibular vascularization is of the terminal type, dependent on the inferior alveolar artery. It is supplemented by a supply from the periosteum. Innervation is provided by the inferior alveolar nerve, terminal branch of the mandibular nerve, third branch of the trigeminal nerve (V3), running in the mandibular canal, within the spongy bone.
The mandible articulates with the base of the skull by the two temporomandibular joints, but also with the facial mass via the dental articulation. The head of the mandibular condyle, ovoid in shape flattened from front to back, is supported by a narrowed neck constituting a zone of weakness that yields more easily to trauma, thus protecting the base of the skull. By undergoing the mechanical constraints imposed by the masticatory forces, it reacts as a physiological pseudarthrosis with reactions of resorption and periosteal apposition.
The basic movements performed by the mandible are: elevation, lowering, propulsion, retropulsion and diduction. Two groups of muscles are involved:
- the elevators constituted by the masseter, temporal and medial pterygoid muscles; the most powerful muscles of the masticatory system, they are inserted into the posterior part of the mandible, on the ramus, protect it from direct shocks, and exert considerable forces on the posterior bony and dental structures;
- the depressors, which are the geniohyoid, mylohyoid and digastric muscles; more fragile muscles, they are inserted into the anterior part of the mandibular arch; they tend to open this arch on its upper edge when it is fractured.
III/ Factors favoring mandibular trauma
- Anatomo-pathological factors: The mandible has areas of weakness and areas of resistance. The areas of weakness are represented by: the incisor region, the premolar region, the angle region, the mandibular neck. On the other hand, there is resistance in the molar region.
- Histopathological factors:
- Bone consistency and architecture:
- Compact bone: The mandible contains a very large portion of it. This very hard and compression-resistant bone responds less well to flexion, especially in areas of curvature. This characteristic is very important on the consequences of a blow.
- Wisdom teeth: Impacted or impacted teeth weaken the maxillary and mandibular bones.
- Other factors :
- .Age and sex of the subject: Most mandibular fractures occur in men aged 20 to 30 years.
- The practice of certain sports: boxing, football, etc.
- Certain dento-maxillary dysmorphoses: a person with mandibular prognathism or maxillary retrognathism will be more exposed to the risk of mandibular fractures.
IV/Physiopathology
1. The mechanism of fractures : The mechanism can be direct or indirect.
– Direct mechanism: The fracture is located at the point of impact.
– Indirect mechanism: The fracture line is located at a distance from the point of impact. Condylar fractures are most often found in this mechanism.
2. Displacements: The displacements encountered in cases of mandibular fractures are a function of the force and orientation of the impact, the fracture line, the dental articulation, and especially the concomitant action of muscular forces on the fractured fragments. There are several types of displacement:
– Lateral movements or shifts,
- Angles,
- Axial rotations,
- Shortenings by overlapping,
V/ Etiologies of mandibular fractures
– Road accidents
– Work accidents
– Sports accidents
– Ballistic trauma
– Fractures caused by animals (kicks from “hooves”)
– Pathological fractures: post-radiation osteitis, osteomyelitis, osteo-chemionecrosis, cysts and tumors that develop at the expense of the mandibular bone), osteoporosis, etc.
Mandibular fractures.
V/ Classification of fractures
- Classification according to anatomical-clinical forms
- Symphyseal and parasymphyseal fractures :
- These are fractures that extend from canine to canine. They most often occur after a direct impact on the chin, which is sometimes accompanied by a condylar fracture. But they can also occur during a lateral impact on the horizontal branches or angles. These fractures can be median, paramedian, vertical, oblique or lambdoid.
- clinical
– pain
– painful lower genial swelling
– speech disorders
– sensory disturbances
– very frequent association of a contralateral condylar fracture
2- Fractures of the horizontal branch region:
- These are fractures located in the premolar and molar regions. They occur during direct and indirect impacts. Usually, a fracture of the contralateral condyle is observed. These fractures most often present displacements. If there is a significant overlap, the inferior dental nerve risks being severed.
- Clinical
- Without displacement: radiologically diagnosed,
- With displacement: we note either
An overlap: and or deviation of the inter-incisal point on the fractured side.
A discrepancy: anterior open bite, premature molar contact.
An angulation: lingo or vestibulo version of the incisors and molars
3- Fractures of the mandibular angle :
- These are fractures that are caused by a violent shock. They occur during a side impact, but also during a violent impact on the chin. The presence of an included wisdom tooth doubles the possibility of having a fracture line.
- Clinical
Anteroposterior pressure on the chin triggers pain at the fracture site.
Very tight trismus.
Deviation of the interincisal point and the chin towards the fractured focus
4- Fractures of the ascending branch :
- These are so-called closed fractures. They are rare and generally there is no displacement because it is a region protected by a significant muscular strap.
- Clinical
lockjaw
pain on palpation.
articulation disorder due to shortening of the BM
5-Coronoid fractures: They are rare and often unrecognized. The diagnosis can be made on panoramic X-ray and on the depressed maxilla.
- The fracture line is generally located at the base of the coronet.
- Clinical
Opening and closing movement of the oral cavity is painfulPain on palpation at the bottom of the vestibule
6- Fractures of the condylar region
They can be:
- intra-articular: condylar or capital
- extra-articular: high or low subcondylar.
- capitals: They are most often due to a vertical shock. The entire top of the condylar head is fractured. Sometimes, there may be a bursting of the condylar head. The clinical picture is marked by painful palpation of the joint. There may be otorrhagia due to fracture of the anterior wall of the external auditory canal.
- High subcondylar fractures: These are extra-articular and occur during an impact on the chin, or from a lateral impact which fractures the neck of the condyle.
The fracture line starts from the neck
Same symptoms as the low subcondylar fracture
Articulation disorder
Shortening of the healthy side
- Low subcondylar fractures: These are extra-articular fractures and they pass at the base of the neck.
The fracture line starts from the sigmoid notch
Pre-tragic ecchymosis
Limitation of mouth opening
No articulation disorder
- Comminuted fracture of the condyle
- Classification by terrain
- In the totally edentulous: The mandible of the elderly subject is characterized by the
frequency of edentation and osteoporosis which lead to resorption of alveolar bone and bone fragility
- Mandible fracture in children: The mandible is relatively less voluminous and more set back in relation to the craniofacial skeleton. Its greater elasticity explains the “greenstick” fractures. The presence of the germ of the permanent teeth weakens the mandible.
VI/ Clinical study
1. Clinical examination
- Examination of the trauma patient: The first thing to do in the presence of a trauma patient is to assess the emergencies. To do this, it is necessary to:
- Ensure airway is clear:
- By removing blood, clots;
- By removing avulsed teeth, foreign bodies, dental prostheses from the oral cavity;
- By avoiding tongue ptosis;
- Controlling bleeding:
- Skin and mucous membrane wounds are carefully cleaned
- and hemostasis
- Beware of pneumothorax:
- Questioning the injured person and those around him: This allows us to clarify:
- The circumstances and time of the accident,
- The mechanism of trauma,
- The age and gender of the injured person,
- The injured person’s background,
- His general condition,
- Any allergies,
- Current treatments,
- The status of tetanus vaccination.
- Exo-oral examination:
- Inspection It allows to show:
- The condition of the skin: erosions, hematomas, skin wounds, loss of substances. Possible deformation of the facial mass. Fluid discharges (blood, saliva, cerebrospinal fluid, etc.)
- Functional impotence: limitation of mouth opening.
- Palpation: It must be bilateral and comparative. It allows:
- To assess the integrity or otherwise of the bony reliefs (mandibular arch, zygomatic arches, malars, orbital frame).
– To look for painful points and areas of skin hypoesthesia.
- Control of sensitivity in the trigeminal nerve territory.
To check the normal mobility of the condyles by placing the little fingers in the external auditory canal (EAC).
- Endo-oral examination: allows:
- Search for wounds and hematomas
- Examination of the teeth: loss of teeth, fractures, condition of remaining teeth, existence of prostheses.
- Examination of the dental articulation: anterior or lateral open bites, abnormal diastemas, premature contacts, etc.
- Look for dental fractures and dislocations.
- Assessment of mobility, displacement or deformation of fragments.
NB/ Research the pulp vitality of the teeth located on either side of the fracture site by thermal or electrical tests ?????
Mandibular fractures.
VII/ Radiological assessment: This complements the clinical examination and allows clinically diagnosed bone lesions to be ruled out or confirmed. Different incidences are used depending on the type(s) of fracture suspected and range from retro-alveolar radiography to CT scan.
- Retro-alveolar radiography: allows the detection of alveolo-dental lesions (coronary, root and alveolar fractures). It thus allows a more detailed analysis of the alveolo-dental ligament.
- Orthopantomogram or panoramic radiography: examination for unraveling in maxillofacial imaging. It is a standard image in maxillofacial imaging for the detection of mandibular fractures.
- The Low Face incidence: It allows the study of the condylar region, the ascending branch, the mandibular angles, the posterior part of the horizontal branch and the mandibular symphysis.
- Blondeau incidence: allows visualization of the mandibular arch and the coronae. This is the basic incidence in maxillofacial traumatology.
- The Maxillary Parachute incidence: allows the horizontal branch, the mandibular angles, the ascending branches and the condyle to be studied in lateral view.
- The Schüller incidence: It allows visualization of the condylar region.
- Hirtz incidence: allows the diagnosis of zygomatic fractures.
- Tomography: with the mouth open and with the mouth closed, allows the temporomandibular joint to be highlighted.
- CT Scan: The Ideal Cliché
VIII/Complications of mandibular fractures
1. Immediate complications
– Obstruction of the upper aerodigestive tract by glossoptosis.
- Hematoma from wound of facial vessels.
- Vascular complications due to arterial dissections
- bleeding from arterial laceration or vascular injury
2. Secondary complications :
– Infection in dental foci: cellulitis, osteitis
– Delayed consolidation and pseudo-arthrosis.
– Neuralgia or labiomental anesthesia secondary to a lesion of the inferior dental nerve.
3. Late complications
– Vicious calluses,
– Occlusal disorders in case of poorly reduced fractures.
– Temporomandibular ankylosis.
Mandibular fractures.
IX./Treatment of mandibular fractures
.1. Purposes of processing
– Restoration of the dental articulation, support of the occlusion,
– Perfect anatomical reduction of the fracture site(s),
– Ensure free mandibular play.
Mandibular fractures.
2. Principles of processing
– Restoration of masticatory function,
– Rehabilitation of mandibular play in the event of joint fractures.
3. Therapeutic means
- Medical treatment:
- Antibiotic therapy is systematic in cases of mandibular fractures. Beta-lactams remain the antibiotics of choice.
- Anti-inflammatory drugs were prescribed in case of associated edema.
- An on-demand analgesic is prescribed in combination with a high-protein liquid diet.
- Oral health by brushing, mouthwashes, extraction of remaining roots is an essential prerequisite.
- tetanus vaccination in the patient.
- Orthopedic treatment: The techniques of closed reduction and blocking of the mandible are varied. The most used
- Ivy ligatures: These are made between two adjacent teeth that are solid. A loop is made by bending the wire on a smooth instrument 2 to 3 mm in diameter and one or two twists are made. The two heads are then introduced from the outside to the inside into the chosen interdental space, then they are brought back separately into the vestibule and one of the wires is passed either behind the loop preferably, or into the twist.
- Arches: These are metal arches fixed to each dental arch by ligatures with steel wires 0.3 or 0.4 mm thick. They can be flat, round, oval or half-ring section. Example: Duclos arch
- Orthodontic Braces: In mixed dentition, the blocks can be obtained from “Brackets” glued to the vestibular faces of certain teeth.
- Surgical treatment: This is open reduction with the use of internal fixators (osteosynthesis)
X/Indications: Indications depend on the type of fracture
- Symphyseal fractures :
- Non-displaced fractures are treated by intermaxillary blocking with mandibular arches or Ivy ligatures. The intermaxillary blocking is maintained for 45 days.
- In case of displaced fractures, reduction and intermaxillary blocking with mandibular arches or osteosynthesis.
2. Fractures of the horizontal branch :
- The treatment consists of performing an intermaxillary blockage using arches and ligatures which will be maintained for 45 days. Osteosynthesis using steel wires or a screwed plate can be performed in the event of significant displacements.
- In children, osteosynthesis is contraindicated due to the presence of dental germs.
- In edentulous patients, osteosynthesis can be performed.
3. Fractures of the mandibular angle : In general, treatment consists of intermaxillary blocking or osteosynthesis with steel wires or a mini screwed plate. Intermaxillary blocking can be associated with osteosynthesis. It is possible to abstain from any therapy in the event of non-displacement
4. Fractures of the ascending branch: Displacements in this region are very rare. Non-displaced fractures are treated with an intermaxillary block for 45 days. On the other hand, displaced fractures can be treated either by osteosynthesis with steel wires associated with an intermaxillary block for 2 to 3 weeks or by osteosynthesis with a screwed plate.
5. Condylar fractures: Treatment of fractures of the condylar region depends on the location of the fracture.
– Articular fractures (capital and condylar) require short-term intermaxillary blocking (approximately 10 days) associated with elastic traction or the use of molar wedges to facilitate reduction of shortening.
Secondly, we carry out a mobilization that aims to recover the function
articular.
– The treatment of extra-articular fractures (upper and lower subcondylar) is identical to that of fractures of the ascending branch. It is necessary to associate it with mandibular gymnastics as early as possible.
6. Fractures of the coronal region: If there is no displacement and no occlusal disorder, drug therapy based on analgesics and anti-inflammatories combined with physiotherapy may be sufficient. In the event of occlusal disorder, a 15-day intermaxillary block is performed.
7. Condylar fractures associated with a fracture of the mandibular arch: Treatment is conditioned by the condylar fracture. Some authors recommend osteosynthesis of the fracture of the mandibular arch, which allows early mobilization of the joint.
Mandibular fractures.
Bibliography
- Dia, M. Fractures of the mandible. About 54 observations collected at the Stomatology Department of Aristide le Dantec University Hospital in Dakar. Thesis. Dental Surgery. Dakar. 1999.
- Rocton S. Mandible fractures: epidemiology, therapeutic management and complications of a series of 563 cases. Rev Stomatol Chir Maxillofac 2007;108:3-12.
- Frison L., Larbi A., Abida S., Goudot P., Yachouh J. Fractures of the mandible. EMC (Elsevier Masson SAS, Paris), Oral medicine, 28-500-V-10, 2011.
Mandibular fractures.
Sensitive teeth react to hot, cold or sweet.
Sensitive teeth react to hot, cold or sweet.
Ceramic crowns perfectly imitate the appearance of natural teeth.
Regular dental care reduces the risk of serious problems.
Impacted teeth can cause pain and require intervention.
Antiseptic mouthwashes help reduce plaque.
Fractured teeth can be repaired with modern techniques.
A balanced diet promotes healthy teeth and gums.