MANDIBULAR FRACTURE in plastic surgery.pptx

mandibular fractures

1. MANDIBULAR FRACTURE Dr. S. V. NARAYANA This Photo by Unknown author is licensed under CC BY-SA-NC .

2. INTRODUCTION Mandible is the largest and the strongest bone of the face, fractures often occur due to blunt and penetrating trauma.   Either isolated or a part of panfacial fracture or may be associated with poly trauma involving head, thorax, abdomen,   and other bones and soft tissues of the body.   Mandibular fractures   may cause an imminent threat to airway and   cause malocclusion, joint dysfunction ,   pain,   infection, nonunion , and facial nerve palsy. Pediatric mandibular fractures are managed differently due to the mixed dentition, different anatomy of teeth, and architecture of the pediatric mandible, and growth potential of the mandibular condyle.   Fractures of atrophic, edentulous mandible are also treated differently.

3. HISTORY

4. The Association for the Study of Internal Fixation (ASIF) in Europe, developed the technique of open reduction and rigid internal fixation in the 1970s, which aimed at primary bone healing achieved by absolute stability of the fracture fixation.   Champy et al in France developed the concept of adaptive osteosynthesis based on the belief that compression plates with rigid fixation were unnecessary because of natural strain of compression along the inferior border of mandible produced by masticatory muscles.   They advocated transoral placement of small and thin, stainless steel miniplates with monocortical screws along an “ideal” osteosynthesis line of the mandible popularly called Champy’s line.

5. ANATOMY MANDIBLE BONE It consists of a curved, horizontal portion, the body, and two perpendicular portions, the rami, which unite with the ends of the body nearly at right angles. The body is divided structurally into basal bone and alveolar (tooth-bearing) bone, and consists of the symphysis, parasymphysis , and alveolar bone.   The symphysis is located in the midline, joining the right and left halves of the mandible.   The parasymphyseal region is located on either side of the symphysis, and spans from canine to canine.  

6. The body is the region from the canine to the angle, the non– toothbearing region between the body and the ramus.   The ramus, the vertical portion of the mandible, extends from the angle toward the zygomatic arch, terminating at the coronoid process and condyle separated by a condylar notch.   The condyle articulates with the glenoid fossa, forming the temporomandibular joint (TMJ).  

7. Morphological changes in the mandible with age  Features At birth Adult Old age Mental foramen Near to lower border Midway between upper and lower border Near upper border Angle of mandible Obtuse ~175° Almost right angle ~110–120° Obtuse ~140° Condyle and coronoid Coronoid larger than condyle Both at the same level Condyle above the level of coronoid Mandibular canal Near lower border Parallel to mylohyoid line Close to alveolar margin Symphysis Bone in two halves united by fibrous tissue Faint ridge in upper part Not Recognizable

8.  Muscles involved in various movements of the mandible MOVEMENT MUSCLES INVOLVED Depression Lateral pterygoid, digastric, geniohyoid, mylohyoid Elevation Temporalis, masseter, medial pterygoid Protrusion Lateral pterygoid + medial pterygoid synchronously Lateral movement Lateral pterygoid + medial pterygoid alternatively Retraction Temporalis posterior fibers, masseter, digastric, geniohyoid

9. BIOMECHANICS : Most complex biomechanical property of mandible is due to curved structure supported on its ends by muscular pterygomassetric sling. Masseter and temporalis muscle creates strong bite force. Medial and lateral pterygoid for opening/excursion. Supra hyoid muscles depress the mandible. 

10. In mandibular fractures;  muscle of mastication pulls the posterior segment upwards, suprahyoid muscle pulls the anterior segment inferiorly. During mastication; external downward forces exerted by tooth to tooth contact cause compression balanced by the tension created by upward pull of the muscles of mastication. Areas of tension and compression depends on the site of mandibular load.

11. EPIDEMIOLOGY The mandible is the second most frequently observed bone to be fractured in faciomaxillary injuries, followed by orbital-zygomatic-maxillary fractures.   In India, male to female ratio is 3.7:1,   significantly higher for males. The highest incidence of mandibular fractures is seen in the age group of 21 to 30 years.

12. ETIOPATHOGENESIS The main cause is road traffic accidents followed by falls, assaults, and sports-related injuries.   Worldwide, the condyle region is the most common site of fracture followed by body fractures. In India parasymphyseal fractures are the most frequent, followed by angle and condyle fractures in occurrence.   Mandibular angle fractures are also found mostly to be associated with assault victims. The most commonly associated injuries are head injuries followed by lower limb fractures.   Multiple mandibular fractures, fracture para symphysis + sub condyle is the commonest followed by fracture body + angle.

13. In infants and preschool children, the most common sites are the condyle, symphysis, and mandibular body.  In edentulous patients, there is a higher percentage of body fractures and lower incidence of angle and symphyseal fractures.     two to threefold increased risk of mandibular angle fracture with the presence of a third molar.   Structurally, the mandible is weak at the neck of the condyle, the angle, especially if a third molar is present, and the mental foramen, where fractures are likely to occur.   The presence of teeth, particularly those with long roots such as the canines, or of unerupted teeth also produce lines of weakness in the mandible.

14. CLASSIFICATION OF MANDIBULAR FRACTURES DINGMAN AND NATVIG CLASSIFICATION According to them, fractures are classified on various basis: According to the direction of the fracture:   Horizontal or vertical and whether it is favorable or unfavorable for treatment. According to the severity of the fracture:   Simple, closed, or compound—toward the oral cavity or the skin.   According to the type of fracture:   Greenstick, complex, comminuted , impacted, or depressed.  

15. According to the presence or absence of the teeth in the jaws:   Dentulous, partially edentulous, edentulous .   According to the location: Region of symphysis. Canine region. Region of body. Region of angle. Region of ramus. Region of condylar process. Region of coronoid process.

16. KAZANJIAN AND CONVERSE CLASSIFICATION

17. FAVORABLE AND UNFAVORABLE FRACTURES OF THE   MANDIBLE The action of various muscles attached to the mandible sometimes helps the fracture segments to stay in place ( favorable ) and sometimes pulls the two segments away ( unfavorable ).   This depends on the direction of the fracture line in horizontal or vertical planes. Horizontally favorable fractures: If the fracture line runs downward and forward, muscles help in preventing displacement at the fracture line. Horizontally unfavorable fractures: If the fracture line runs down- and backward, muscles in this case will pull the segments apart and cause displacement.

18. CLINICAL FEATURES Diagnosis can often be made by clinical features alone; however, further imaging is usually needed for precise assessment of the fracture and excludes multiple fractures. SYMPTOMS Fracture of the mandible may be associated with the following symptoms: Pain. Abnormal bite. Numbness. Bleeding. Swelling. Dyspnea .

19. SIGNS Examination of head, neck, and oral cavity may reveal the following signs: Deformity: External deformity may be difficult to Appreciate clinically due to swelling. Deviation of mouth. Restricted function: Mouth opening may be restricted. Lateral deviation on opening the jaw. Intraoral examination may reveal a step deformity or a gap in dentition, open bite deformity, and malocclusion.

20. Tears in mucosa and ecchymosis often indicate underlying fractures.  There can be significant bleeding, of condylar fractures, producing visible  hemorrhage , sublingual hematoma , and swelling, due to associated soft tissue injury. Tenderness:  Fracture sites are tender to palpation, and Crepitus:  Crepitus may be produced by the grating of   the rough surfaces when the bony ends come into contact   with each other.

21. Contusions over the chin or preauricular area, hemotympanum, and malocclusion should raise the suspicion of condylar fractures. Sensory disturbances: Fractures of the inferior alveolar canal can cause temporary or permanent anesthesia of the lip, teeth, and gingiva due to injury to inferior alveolar nerve.   The lingual nerve lies close to the lingual cortex near the mandibular third molar. Injury may cause temporary or permanent anesthesia to the ipsilateral tongue and gingiva. Airway compromise: posterior tongue displacement in bilateral mandibular fractures producing “flail mandible” or sublingual hematomas or traumatic tongue muscle avulsion.

22. OCCLUSAL EVALUATION Changes in occlusion are highly suggestive of a mandibular fracture.   Mesial: Toward the midline of the dental arch   Distal: Toward the back of the dental arch (or away from the midline.

23. ANGLE’S CLASSIFICATIONS OF MALOCCLUSION: Class I (or neutrocclusion ): In this normal relationship, the maxillary first molar is slightly posterior to the mandibular first molar; the mesiobuccal cusp of the maxillary first molar is directly in line with the buccal groove of the mandibular first molar. The facial profile is termed mesognathic . Class II (or distocclusion ): the buccal groove of the mandibular first molar is distal to the mesiobuccal cusp of the maxillary first molar. The facial profile is termed retrognathic. Class III (or mesiocclusion ): the buccal groove of the mandibular first molar is mesial to the mesiobuccal cusp of the maxillary first molar. The facial profile is termed prognathic  

24. Modalities of Diagnosis ORTHOPANTOMOGRAM ( PANOREX ) This is a panoramic tomographic scan that shows the entire mandible, including condyles, on one film   If well taken, the orthopantomogram (OPG) will show most of the fractures except those located in the symphyseal region An excellent screening tool offers benefits of low radiation, low cost, and excellent detail. Orthopantomogram (OPG) showing bilateral condylar fracture, undisplaced on right and displaced on the left side.

25. PLAIN RADIOGRAPHS Three films are used to image isolated mandibular fractures: A posteroanterior (PA) showing a PA view of angle and ramus fractures. A reverse Towne of a PA view, showing medial/lateral displacement of condylar and subcondylar fractures Bilateral oblique views for body and angle fractures.

26. CT SCAN A high-resolution computed tomography (CT) is currently the imaging procedure of choice for most facial fractures. CT scans are 100% sensitive for mandibular fractures compared with 86% for panoramic radiographs.   CT is generally the preferred method of imaging for multiple mandibular fractures and is especially helpful in patients requiring images of the cervical spine, cranium, and carotid arteries.   A CT scan with three-dimensional (3D) reconstruction can aid in the diagnosis and treatment planning of complex facial fractures. A cone beam CT (CBCT) is effective for the diagnosis of suspected mandibular fractures with equivocal clinical and radiological signs.

27. MRI SCAN Magnetic resonance imaging (MRI) is better for evaluating soft tissue disease, such as hematoma and complications of trauma.

28. TREATMENT Mandibular fractures are often just a part of polytrauma.   Such a patient is best managed by Advanced Trauma Life Support (ATLS) protocol.   Once airway, breathing, circulation, and cervical stabilization have been addressed, the secondary survey is initiated     This starts with the “AMPLE” history ( A llergies, M edications, P ast illnesses, L ast meal, E vents/environment/mechanism of injury), followed by a detailed head-to-toe examination. T he patient is maintained on a soft diet, Medication for pain control, and antibiotics for all open fractures (including fractures involving tooth roots).

29. Principles of treatment of mandibular fractures include the following: To establish preinjury occlusion. Rapid restoration to full function and mobility.   Pain-free articular apparatus at rest and during function. To achieve healing without infection or complications.

30. ANTIBIOTIC PROPHYLAXIS Fractures through tooth-bearing regions are considered open and should receive antibiotics as soon as possible after diagnosis.   Numerous studies have shown that administrating antibiotics before the operative procedure reduces the rate of postoperative infection in fractures of mandible

31. INDICATIONS OF CLOSED AND OPEN REDUCTION OF FRACTURE MANDIBLE Type of Fracture Reduction Indications Closed reduction Nondisplaced favorable fractures Coronoid fractures Condylar fractures Pediatric fractures Open reduction Displaced unfavorable fractures through the angle of the mandible Complex facial fractures requiring a stable mandibular base Condylar fractures not suitable for closed reduction Atrophic edentulous mandibles

32. CLOSED REDUCTION Mandibular fractures with good dentition on either side of the fracture line may be treated in some cases by a period of MMF. Erich arch bars are considered the standard in MMF . Once the arch bars are fitted on both maxillary and mandibular dentition, placement of wires or elastics is done in maximum intercuspation. Intermaxillary fixation (IMF) screws are used for minimally displaced fractures when the patient has a full dentition.  

33. They are 2.5-mm stainless steel self-tapping screws in 8- to 12-mm length positioned superior to   the maxillary and inferior to the mandibular tooth roots and are inserted either medial or lateral to the long axis of the canine roots. 

34. OPEN REDUCTION Surgical approach depends on the associated soft tissue injury and type of bony injury.   Existing lacerations: Soft tissue injuries often accompany facial fractures and can be used to directly access the fractured bone for open repair. Intraoral approach: Intraoral incisions avoid external scars. Labial sulcus incision: Symphysis and parasymphysis fractures are easily accessed through a labial sulcus incision. Vestibular incision: Body, angle, ramus, and condyle fractures can be accessed through a vestibular incision that may extend past the external oblique line to the midramus . This can be used with transbuccal trocar approach for screw placement.

35. Submental and submandibular approach: This approach can be used to treat fractures of the anterior mandibular body and symphysis. Retromandibular approach: This will give access to the ramus and subcondylar region of the mandible. It facilitates the reduction and fixation of subcondylar fractures and is generally preferred to preauricular approach .   Preauricular approach: The preauricular approach is excellent for exposure to the TMJ. It is sometimes combined with retromandibular approach.

36. OSTEOSYNTHESIS Osteosynthesis is the reduction and fixation of a bone fracture with implants. Wire Osteosynthesis it can be used for limited definitive fixation in combination with rigid fixation.   It is sometimes used for helping to align fractured segments before rigid fixation. The wire is prestretched soft stainless steel to reduce stretching and loosening postoperatively.   Plate Osteosynthesis Internal fixation for mandibular fractures can be divided into two categories: load-bearing and load-sharing fixation.

37. Load-bearing fixation  denotes a fixation that is capable of bearing all of the load generated by mandibular   function so that the fracture site is not exposed to any functional load.  Typically, this is achieved by a large reconstructive plate applied to the inferior border of the mandible.  This is beneficial when there is insufficient bone stock at the fracture site, for instance, pathological fractures, comminuted fractures, and fractures in atrophic mandibles.   Load-sharing fixation on the other hand where the functional load is shared between the fixation hardware and the bone at the fracture site. Champy popularized the load-sharing miniplate fixation along the ideal lines of osteosynthesis.

38. Load-sharing fixation can further be divided into  rigid  and  nonrigid  (functionally stable) fixation.  The main difference between rigid and nonrigid fixation  centers   on interfragmentary mobility. Nonrigid fixation allows micromotion at the fracture site but provides sufficient stability to allow bone healing with callous formation.   Examples include a single miniplate along the oblique ridge of the mandible for angle fractures or a single miniplate and an arch bar for body or symphyseal fractures.   R igid fixation restricts micromotion and allows primary bone healing without callus formation.   Examples include two miniplates, multiple lag screws, or small reconstruction plate.   Load-sharing fixation is suitable only for isolated simple fractures with good bone-to-bone contact at the fracture line.

39. Locking versus Nonlocking Plates Tightening screws on a nonlocking plate that is poorly adapted pulls the bone segments toward the plate, which may affect alignment and thus occlusion.   Locking plates do not do this because the screw head is threaded, which engages a complimentary thread in the plate hole. Therefore, locking plate should prevent malocclusion They also preserve cortical bone perfusion and are less likely to loosen from the plate.

40.   Lag Screw Fixation Lag screw fixation was first described by Brons and  Boering , who postulated that lag screw not only immobilizes the fracture fragments but also produces a constant compression of the fracture area. The near cortex is drilled drill should ideally be at 90 degrees to the fracture plane. Generally, two screws are   necessary to achieve stable fixation.  Lag screw technique is   indicated in noncomminuted symphysis or  parasymphysis   fractures 

41. Specific Treatment Based on Fracture Locations An algorithm for the treatment of noncondylar mandibular fractures was presented by Ellis

42. SYMPHYSIS AND PARASYMPHYSIS Mandibular symphysis undergoes twisting (torsion) forces. Simple fractures can be treated with arch bars and 4 to 6 weeks of MMF alone.   Plate osteosynthesis requires two straight miniplates or a reconstruction plate.   The farther apart (superior–inferior) the plates, the more stable the fracture site.   Reduction can be assisted by inferior border wire or monocortical screws/clamp. Mental nerve and tooth root injury must be avoided.   Lag screws placement can provide a low-cost treatment for noncomminuted symphysis or para symphysis fractures.

43. BODY Simple body fractures can be treated with arch bars and 4 to 6 weeks of MMF alone.   They can also be treated with MMF with miniplate fixation. Plate osteosynthesis requires two straight miniplates.   Comminuted fractures may require reconstruction plate fixation.

44. ANGLE Mandibular angle fractures are associated with the highest complication rate of all mandibular fractures. To avoid complications and achieve good functional outcome, management should be based on understanding the biomechanics at the site of fracture.   As a result of contraction of muscles producing jaw function, tension occurs at the level of the dentition, whereas compression occurs along the lower border of the mandible.

45. A zone of no tension or compression is found between the   superior and inferior borders known as the  neutral  zone. The use of a single miniplate along the tension zone prevents separation at the fracture site, whereas if the plate is located in the zone of compression, the plate will be stressed in line and bend, creating an unstable osteosynthesis 

46.   Recommended treatment to stabilize mild to moderately displaced favorable fractures are application of a single plate along the oblique ridge.   For moderate to severely displaced unfavorable fractures, two lateral border plates or fixation using 3D plate is generally preferred.   Application of a single miniplate along the oblique ridge is associated with the lowest number of complications and is the easiest operation to perform. For additional stability, a second inferior border plate via transcutaneous trocar technique can be added to a superior border plate but, in practice, results not good

47. Complex fractures may require reconstruction plate fixation using submandibular approach.   Mandibular angle fractures can occur in combination with many other mandibular fractures, most commonly contralateral parasymphysis or body.   One of the two fractures must be treated with rigid fixation, and then the other can be treated with a single miniplate.   The most accessible f racture (i.e., the symphysis or body fracture) can be fixed with  thicker, stronger plate, two miniplates, lag screws, or a combination of these, and then the angle fracture can be treated with a single miniplate.

48. CONDYLE Condylar fractures are one of the most controversial in terms of treatment. Condylar fractures include fractures of condylar head, condylar neck, and subcondylar region. Apart from this, the degree of displacement, dislocation, and angulation of fractured segments also dictates optimum treatment.   Ellis proposed a simple classification system based on location of the fracture: Condylar head fracture: Intracapsular fracture.   Condylar neck fracture: Fracture below the condylar head, but on or above the lowest point of the sigmoid notch.   Condylar base fracture: Fracture in which the fracture line is located below the lowest point of the sigmoid notch.  

49. The AO Foundation expanded on Ellis’ classification by subclassifying neck fracture into “high-neck” and “low-neck” Strasbourg Osteosynthesis Research Group (SORG) classification defines three main types of condylar fractures.   This classification describes “Line A,” a perpendicular line through the lowest point of sigmoid notch to the tangent of the ramus. Diacapitular fracture (through the head of the condyle): The fracture line starts in the articular surface and may extend outside the capsule   Fracture of the condylar neck: The fracture line starts somewhere above Line A and runs above Line A for more than half of its length   Fracture of the condylar base: The fracture line extends behind the mandibular foramen and runs below Line A for more than half of its length They also defined “minimal displacement” as a displacement of less than 10 degrees or overlap of the bone edges by less than 2 mm, or both.

50. Fractures of the condylar neck are more common and result in more, clinically apparent malocclusion.   MMF with elastics is recommended to be applied for a period of 4 to 6 weeks in most cases.   Open access may be external, transoral, or transoral endoscopic-assisted ORIF. Facial nerve monitoring and endoscopic-assisted reduction with internal fixation can reduce the risk.   Majority of unilateral condylar fractures can be treated closed with MMF with arch bars and application of elastic MMF for 4 to 6 weeks In case bilateral fractures, treating at least one of these fractures by ORIF may be the best form of treatment.

51. A bsolute indications for the open treatment of condylar fracture. A dequate occlusion cannot be obtained through closed reduction. Condylar fractures in conjunction with significant comminuted midface fractures. Mechanical obstruction of jaw opening. A nterior open bite.

52. CORONOID Coronoid fractures are not treated unless a severe dislocation of the fractured coronoid is observed or it impinges on the zygomatic arch.   Conservative treatment, together with the ORIF of associated fractures.   The crucial point is to prevent ankylosis, which may be prevented by correct and early postoperative physiotherapy and mandibular function.   Operative treatment In case malocclusion, and severe displacements.     The surgical technique employed is removal of the fractured segment and immediate postoperative exercises.   Malunion of coronoid may require transoral coronoidectomy .

53. ATROPHIC FRACTURES OF MANDIBLE Atrophic fractures are generally categorized as those with less than 15 mm of bone height at the fracture site.   An atrophic mandible is more vulnerable to fracture because of the decreased bone volume.   Current recommendations include using a small reconstruction plate.   The use of 2.4-mm reconstruction plates and bicortical screws.   Ellis and Price recommend the use of 2-mm locking plates with a subperiosteal extraoral approach using immediate bone grafts

54. PATHOLOGICAL FRACTURES OF THE MANDIBLE Occur in regions where bone has been weakened by an underlying pathological process . These are rare, accounting for fewer than 2% of all fractures of the mandible. Osteoradionecrosis ,   Following third molar removal or implant placement,   Secondary to osteomyelitis, bisphosphonate-related osteonecrosis of the jaw, because of cystic lesions, benign, malignant, or metastatic tumors .   Management of pathological fractures is aimed initially at systemic issues, followed by focusing on site-specific issues.  

55. PEDIATRIC MANDIBULAR FRACTURES   Approximately 40% of pediatric facial fractures, as a result of motor vehicle accidents and falls.   The condyle being the most common site involved The most important difference is the dentition, which guides the decision-making while managing these fractures.   Pediatric teeth have poor retentive qualities, making them poor candidates for circumdental wire and arch bar fixation.   Condyle is the growth center for the mandible ,trauma may cause growth retardation, malocclusion, and facial asymmetry.

56. MANAGEMENT OF PEDIATRIC MANDIBULAR FRACTURES The clinical presentation very deceptive, the chief complaint is simply a chin laceration and jaw pain.   It is easy to overlook the fracture, and a high index of suspicion is essential for diagnosis.   A preoperative panoramic radiograph is useful in evaluating the position of the developing tooth buds.   Radiographs should also be taken postoperatively to ensure that none of the screws is transfixing a tooth bud.   If this is seen, the plate should be removed as soon as the fracture has healed.

57. Treatment options should be weighed against the risk of causing further harm to facial development Before 2 years of age, a child’s jaws are often edentulous and a fracture reduction would require an acrylic splint also known as a gunning splint fixed with circummandibular wires. At ages 2 to 5 years, deciduous teeth are present and conical in shape. Interdental wiring may be used for fixation. Arch bars are difficult to secure. Between 6 and 12 years, the mixed dentition, primary teeth are resorbing and often are loose.   Strong deciduous or permanent teeth can be used, but when dentition is not available, splints may be used. At ages 9 to 12 years, MMF using arch bars is possible

58. PEDIATRIC CONDYLAR FRACTURES Condylar fractures are the most common pediatric mandibular fracture and present bilaterally in 20% of cases.     Condylar fractures are classified into three groups: Intracapsular (articular cartilage) condylar fractures: Common in children younger than 6 years causing hemarthrosis, subsequent bony ankylosis, and affect mandibular growth. High condylar fractures: Occur above the sigmoid notch. Low subcondylar fractures: Usually are greenstick fractures in children and are the most common type of pediatric mandibular fracture overall.

59. TREATMENT OF PEDIATRIC CONDYLAR FRACTURES The two main goals for treatment in such patients are preservation of function and maintenance of ramus height.   Most condylar fractures in children are treated nonoperatively with early treatment, including analgesics, soft diet, and early progressive range-of-motion exercises. Comminuted and displaced fractures of the head and condyle and those causing malocclusion are immobilized in MMF for 7 to 10 days.   Bilateral fractures causing open bite, severe movement limitation, or deviation are immobilized in MMF for 2 to 3 weeks followed by early progressive range-of-motion exercise to avoid ankylosis.

60. OPEN REDUCTION IS INDICATED  : Dislocation of the mandibular condyle into the middle cranial fossa. Condylar fractures prohibiting mandibular movement. In bilateral condylar fractures causing reduced ramus height and anterior open bite. Depending on the fracture site, the open surgical approach to the pediatric condyle is similar to that of the adult condyle.

61. POSTOPERATIVE CARE Diet: patient can have any meal by adding a liquid like water or broth to suck through a straw and through the teeth. Oral hygiene: Regular rinsing and daily brushing of the teeth and arch bars should be stressed.   Brushing is avoided for a week if there is an intraoral incision. Emergencies: In case of emergencies, such as patient becoming unconscious and requiring assistance with the airway, wires between the arch bars will need to be cut.   In case the patient feels to vomit, bending the head forward will allow the vomitus to flow out of mouth and nose.   Sharp wires: Dental wax can be used to protect the buccal mucosa from the sharp edges of the wires and arch bars

62. COMPLICATIONS Mandibular fracture complication rates range from 7 to 42 % and have been correlated to fracture severity. Implant Failure and Migration   Infection Nonunion Malunion and Malocclusion   Nerve Injuries TMJ Ankylosis

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