Orthognathic Surgery Basics

Question 1

What causes facial ‘abnormalities’?

Answer 1

• Congenital
• Trauma
• Psychological = body dysmorphia, hyperchondriacal neurosis
• Racial characteristic
• Familial traits

Question 2

What is examined E/O?

Answer 2

• Aesthetic proportions
  
  • -> Lip and nose morphology
• Vertical, horizontal AP

Question 3

What special investigations are carried out?

Answer 3

RADIOGRAPHS

• OPT
• Cephs (lat = assess jaw bones to base of skull, PA = asymmetry vertical and lateral)
• PA
• Occlusals
• CT

STUDY MODELS
- Face-bow, wax bite, articulator

CLINICAL PHOTOS

• Resting, smiling
• Profile (R & L)
• Teeth

Question 4

Who is apart of the MDT?

Answer 4

• Psychologist
• Orthodontist
• Orthognathic surgeon
• Anaesthetist
• Specialised nurse
• Restorative dentist
• Periodontal dentist
• Speech and language therapist

Question 5

What diagnoses are there for the maxilla?

Answer 5

• Prognathic
• Retrognathic
• Asymmetry
• Vertical excess/ deficiency

Question 6

What diagnoses are there for the mandible?

Answer 6

• Prognathic
• Retrognathic
• Asymmetry

Question 7

What surgical procedures are performed on the maxilla?

Answer 7

• Le Fort I osteotomy +/- distraction (superior, inferior, anterior- cannot move back due to pterygoid plate)
• Anterior maxillary osteotomy (posterior)

Question 8

What surgical procedures are performed on the mandible?

Answer 8

• Advancement
  
  • -> Bilateral sagittal split osteotomy (BSSO)
  • -> Inverted ‘L’ ramus osteotomy
• Set-back
  
  • -> Bilateral sagittal split osteotomy (BSSO)
  • -> Body osteotomy

Question 9

What surgical procedures are performed on the chin?

Answer 9

• Advancement
• Set-back
• Rotation
• Augmentation
• Reduction