MANDIBULAR FRACTURES

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• Mandibular fracture is more common than middle Mandibular fracture is more common than middle third fracture third fracture (anatomical factor)(anatomical factor)

• It could be observed either alone or in combination It could be observed either alone or in combination with other facial fractureswith other facial fractures

• Minor mandibular fracture may be associated with Minor mandibular fracture may be associated with head injury owing to the cranio-mandibular head injury owing to the cranio-mandibular articulationarticulation

• Mandibular fracture may compromise the patency of Mandibular fracture may compromise the patency of the airway in particular with loss of consciousnessthe airway in particular with loss of consciousness

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• Mandible was more sensitive to lateral impact than Mandible was more sensitive to lateral impact than frontal onefrontal one

• Frontal impact is substantially cushioned by Frontal impact is substantially cushioned by opening and retrusion of the jawopening and retrusion of the jaw

• Fracture of condyle regarded as a safety mechanism Fracture of condyle regarded as a safety mechanism to the patientto the patient

• Long canine tooth and partially erupted wisdoms Long canine tooth and partially erupted wisdoms

represent line of relatively weaknessrepresent line of relatively weakness

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Anatomical considerationsAnatomical considerations

Attached muscles:Attached muscles:• MasseterMasseter• TemporalisTemporalis• Medial and lateral Medial and lateral

pterygoidpterygoid• MylohyoidMylohyoid• Geniohyoid and Geniohyoid and

genioglosusgenioglosus• anterior belly of anterior belly of

digastricsdigastrics

Anterior Muscles

Weaker force

Mylohyoid, geniohyoid, genioglossus, platysma, anterior digastric muscles

Muscle action depresses and retracts (open mandible)

Posterior Muscles:

Stronger force

Temporalis Muscle Masseter Muscle

Medial Pterygoid Muscles

Lateral Pterygoid Muscles

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Sites of fracturesSites of fractures• Condyle fractureCondyle fracture

– Intracapsular fractureIntracapsular fracture

– Extracapsular fractureExtracapsular fracture• High condyle neck fractureHigh condyle neck fracture

• Low condylar fractureLow condylar fracture

• Angle/ ramus fractureAngle/ ramus fracture (body (body fracture)fracture)

• Canine regionCanine region (parasymphesial (parasymphesial fracture)fracture)

• Midline fractureMidline fracture (symphesis (symphesis fracture)fracture)

• Coronoid fractureCoronoid fracture (rare) (rare)

Classification by Favorability

Favorable

Unfavorable

Classification by Type of Fracture

Open versus Closed

Fracture Pattern: Communited, oblique, transverse, greenstick

Pathologic: fractures secondary to bone disease (eg, osteogenic tumors, osteoporosis)

Dental Classification

Class I

Class II

Class III

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Clinical assessment and diagnosis Clinical assessment and diagnosis

• History of traumaHistory of trauma (traumatized patients with possible head injury) and facial (traumatized patients with possible head injury) and facial

injuriesinjuries

• Clinical ExaminationClinical Examination▶▶ Extra oralExtra oral

Inspection (assessment of asymmetery, swelling, ecchymosis, Inspection (assessment of asymmetery, swelling, ecchymosis, laceration and cut wounds)laceration and cut wounds)

Palpation for eliction of tenderness, pain, step deformity and Palpation for eliction of tenderness, pain, step deformity and malfunctionmalfunction

▶▶ Intra oralIntra oral bleeding, heamatoma, gingival tear, disturbance of bleeding, heamatoma, gingival tear, disturbance of

occlussion and step deformity and sensory and motor occlussion and step deformity and sensory and motor deficiencydeficiency

• Tongue blade test: have patient bite down while you twist. If no fracture, you will be able to break the blade.

Tongue blade test

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Radiographs Radiographs

• Plain radiographPlain radiograph• OPGOPG• Lateral obliqueLateral oblique• PA mandiblePA mandible• AP mandible (reverse AP mandible (reverse

Townes)Townes)• Lower occlusalLower occlusal

• CT scanCT scan• 3-D CT imaging3-D CT imaging

MANAGEMENT

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Principles of treatmentPrinciples of treatmentsimilar to elsewhere fractures in the bodysimilar to elsewhere fractures in the body

• Reduction of fragments in good positionReduction of fragments in good position

• Immobilization until bony union occursImmobilization until bony union occurs

These are achieved by:These are achieved by:• Close reduction and immobilizationClose reduction and immobilization• Open reduction and rigid fixationOpen reduction and rigid fixation

Other objective of mandible fracture treatment:Other objective of mandible fracture treatment:• Control of bleedingControl of bleeding

• Control of infectionControl of infection

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Definitive treatment Definitive treatment Soft tissue repairSoft tissue repair• DebridmentDebridment• Irrigation with saline and antibioticsIrrigation with saline and antibiotics• Closure in layersClosure in layers• Dressing Dressing

Reduction and fixation of the jawReduction and fixation of the jaw▶▶ Close reduction and IMF (traditional Close reduction and IMF (traditional

method by means of manipulation)method by means of manipulation)▶▶ Open reduction and semi-rigid fixation Open reduction and semi-rigid fixation

(using inter-ossous wirings)(using inter-ossous wirings)▶▶ Open reduction and rigid fixation (using Open reduction and rigid fixation (using

bone palates osteosynthesis)bone palates osteosynthesis)

2020

Close reductionClose reduction

Bonded bracketsBonded brackets

IMF screwsIMF screws

Dental wiring:Dental wiring:• Direct wiringDirect wiring• Eyelet wiringEyelet wiring• Local anesthesia orLocal anesthesia or

sedationsedation

• Minimal displacementMinimal displacement• IMF for 6 weeksIMF for 6 weeks Treatment can be performed Treatment can be performed

under GA or LA and when under GA or LA and when surgery is contraindicatedsurgery is contraindicated

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Close reductionClose reduction

• Arch barsArch bars

▶▶ IMF prior to rigid fixationIMF prior to rigid fixation

▶▶ For the purpose of close For the purpose of close reductionreduction

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Gunning’s splintGunning’s splint

• Old modalityOld modality• Edentulous patientEdentulous patient• Rigid fixation is not Rigid fixation is not

possiblepossible• To establish the To establish the

occlusionocclusion

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Open reduction and fixationOpen reduction and fixation

• Intraoral approachIntraoral approach

• Extraoral approachExtraoral approach

▶▶ Submandibular Submandibular approachapproach

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Rigid fixationRigid fixation

• Intraossous wiringIntraossous wiring• Plates and screwsPlates and screws• Kirchener wireKirchener wire• Lag screwsLag screws

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Reconstruction palateReconstruction palate

Severe trauma

Loss of part of the bone

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Condylar fracturesCondylar fractures

• Intraoral approachIntraoral approach

Ramus incisionRamus incision

• Extraoral approachExtraoral approachPreauricular approachPreauricular approach

Retromandibular approachRetromandibular approach

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Fracture mandible in childrenFracture mandible in children

• Close reductionClose reduction• Open reduction and Open reduction and

fixationfixation• Plating at the inferior Plating at the inferior

borderborder• Resorbable platesResorbable plates

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Teeth in the fracture lineTeeth in the fracture line

• The fracture is compound into the mouthThe fracture is compound into the mouth

• The tooth may be damaged or lose its The tooth may be damaged or lose its blood supplyblood supply

• The tooth may be affected by some The tooth may be affected by some preexisting pathologypreexisting pathology

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Management of teeth retained in fracture Management of teeth retained in fracture lineline

• Good quality intra-oral periapical radiographGood quality intra-oral periapical radiograph• Insinuation of appropriate systemic antibiotic Insinuation of appropriate systemic antibiotic

therapytherapy• Splinting of tooth if mobileSplinting of tooth if mobile• Endodontic therapy if pulp is exposedEndodontic therapy if pulp is exposed• Immediate extraction if fracture becomes Immediate extraction if fracture becomes

infectedinfected• Follow up for 1 year and endodontic therapy if Follow up for 1 year and endodontic therapy if

there is a loss of vitalitythere is a loss of vitality

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Absolute indicationsAbsolute indications• Longitudinal fractureLongitudinal fracture• Dislocation or subluxation from socketDislocation or subluxation from socket• Presence of periapical infectionPresence of periapical infection• Infected fracture lineInfected fracture line• Acute pericoronitisAcute pericoronitis

Relative indicationsRelative indications• Functional tooth that would be removedFunctional tooth that would be removed• Advanced caries or periodontal diseases Advanced caries or periodontal diseases • Tooth in untreated fracture presenting more than 3 Tooth in untreated fracture presenting more than 3

days after injurydays after injury

Surgical Complications

Chin and Lip Hypesthesis Osteomyelitis Malunion Nonunion Plate Exposure Marginal Mandibular Nerve Injury Necrosis of Condylar Head (Aseptic Necrosis) TMJ Ankylosis Dental Injury