Mandibular Fractures - Part 1

Mandibular Fractures - Part 1

• The mandible is the largest, heaviest, and strongest bone in the face.
• It plays a crucial role in airway, facial contour, chewing, swallowing, and speech.
• It is highly susceptible to injury due to its prominent position.
• The mandible's body is horseshoe or parabolic shaped.
• Two rami project upward from the posterior aspect of the body.
• The condylar processes articulate with the temporal bone to form the temporomandibular joints (TMJs).
• The central blood supply is the inferior alveolar artery.
• The peripheral blood supply is the periosteum.

Classification of Mandibular Fractures

• Kruger's General Classification:
  • Simple (closed): Linear fracture, no communication with the exterior or the interior.
  • Compound (open): Fracture with communication to the exterior (skin) or interior (mucosa/periodontal membrane).
  • Comminuted: Bone is splintered or crushed into multiple pieces.
  • Complicated/Complex: Fracture associated with vital structure damage, impacting treatment and prognosis.
  • Impacted: One fragment is firmly driven into another, showing minimal or no clinical movement.
  • Greenstick: Incomplete fracture often seen in children due to the bone's resilience.
  • Pathological: Spontaneous fracture resulting from pre-existing bone pathology or mild injury.

Classification Based on Anatomical Location

• Rowe and Killey's Classification:

  • Dentoalveolar: Fractures not involving the basal bone.
  • Basal Fractures: Fractures involving the basal bone, subdivided into: single unilateral, double unilateral, bilateral, or multiple.

• Dingman and Natvig Classification: Classifies based on specific anatomical regions like symphysis, canine region, body, angle, ramus, coronoid, condylar region, and dentoalveolar region.

Classification Based on Relation to Site of Injury

• Direct Fractures: Fracture occurs at the site of impact.
• Indirect (Countrecoup) Fractures: Fracture occurs opposite the site of impact.

Classification Based on Completeness and Direction of Fracture

• Complete/Incomplete Fractures: Indicates if the entire width of the bone is fractured or just a portion.
• Favorable/Unfavorable Fractures: Describes the fracture line's orientation relative to the treatment and healing potential. This is based on the horizontal or vertical direction of the fracture line.

Mandibular Fractures in Children

• Incidence is less than 2% in children before age 5.
• Factors that contribute to lower fracture incidence in children include:
  • Sheltered environments.
  • Less facial mass.
  • Soft, pliable bone.
  • Protective function of buccal and lingual plates.
  • Tight periosteum.

Clinical Symptoms of Fractures in Children

• Pain
• Swelling
• Malocclusion
• Abnormal mobility in the dental arch
• Step deformity in the dental arch

Treatment - Conservative Therapy

• Indicated for crack or greenstick fractures without malocclusion.
• No need for fixation is required.
• Fluids and soft food are advised for 10-14 days.

Treatment-Conservative Therapy with Splints

• Lateral compression splints are prepared and fixed using circummandibular wiring.
• Used in children's complete deciduous dentition or mixed dentition.

Treatment - Open Reduction

• Surgery is rarely necessary, usually reserved for displaced and multiple fractures.
• Intraosseous wiring or bone plating used in these cases, avoiding harm to developing teeth.

Management of Mandibular Fractures in Adults - Closed Reduction

• Dental arch wires or arch bars adjust for occlusion, followed by IMF (intermaxillary fixation).
• Immobilization period is usually 6 weeks, with a potentially longer period in older/edentulous adults.

Closed Reduction - Indications

• Nondisplaced favorable fractures.
• Grossly comminuted fractures.
• Severely atrophic edentulous mandible.
• Insufficient soft tissue coverage over the fracture.
• Fractures in children with growing teeth.
• Coronoid process fractures.

Closed Reduction - Advantages

• Relatively simple.
• Low cost.
• Noninvasive.

Management of Mandibular Fractures in Adults - Indications for Open Reduction

• Displaced unfavorable fractures.
• Multiple fractures.
• Associated midface fractures.
• Associated condylar fractures
• When IMF (intermaxillary fixation) is contraindicated or not possible.
• To preclude the need for IMF.
• To facilitate the patient's early return to work.

Management of Mandibular Fractures in Adults - Contraindications for Open Reduction

• General anesthesia or long procedure are not advisable.
• Severe commination with loss of soft tissue.
• Gross infection at the fracture site.
• Patient refusal.

Surgical Approaches to the Mandible

• Intraoral: Symphysis & Parasymphysis, Body, Angle, Ramus
• Transbuccal incision: Body, Angle, Ramus
• Extraoral: Submandibular (Risdon's incision).

Explore the anatomy and classification of mandibular fractures in this quiz. Understand the importance of the mandible in various functions and its susceptibility to injury. Test your knowledge on the different types of fractures and their characteristics.