Teeth abnormalities, TMD, cleft lip, surgery Flashcards
(136 cards)
contraindications to orthognathic surgery
BMI >30 Bleeding problems Bisphosphinates Severe mental health issues small condyles/TMJ problems increase risk of relapse
Steps to orthognathic surgery
[4]
- Joint clinic and facial planning
- Pre-surgery ortho (2yrs)
- Surgery
- Post-surgery ortho (6months)
What is involved in pre-orthoganthic surgery orthodontics
- Extractions
- Remove dental compensation (anterior teeth) - will make class 3 and 2 patients look worse
- close gaps and align teeth
- coordinate arch widths
- level the arches
- place rigid fixation wires
What is involved in post-orthoganthic surgery orthodontics
Elastics and fixed wires used to close the gaps between the arches and secure everything in place in the new ICP.
Different orthognathic surgery techniques - list
- Bilateral sagittal split osteotomy
- Le Fort 1 osteotomy
- surgically assisted rapid maxillary expansion SARME
- Genioplasty
what is the risk of numbness to the lower lip after orthognathic surgery
30-40% permanent
How is cleft lip/palate caused
lack of mesenchyme or failure to fuse in vitro
Cleft lip and palate aetiology
Genetic + environmental
Genetic - 40% FH
Environmental - nutritional deficiency, anaemia, alcohol, smoking, obesity, anti-convulsant medication
What is a subcutaneous cleft palate/signs
translucent/blue area, bifid uvula, eating problems - where the mucosa is normal but overlying a cleft palate
Most common cleft/lip palate presentations
50% Cleft lip and palate
30% Cleft palate
20% Cleft lip
Syndromes/disorders associated with cleft lip/palate
Van der Woude
Pierre Robin
Stickler
Foetal alcohol spectrum
Pierre robin syndrome
Cleft palate, floppy tongue, mandibular retrognathia = Difficulties eating and breathing = nasopharnygeal and feeding tubes.
Can be associated with Sickler syndrome.
Stickler syndrome
Connective tissue disorder causing cardiac and retinal problems - associated with Pierre Robin sequence and cleft plate
Van der Woude syndrome
Cardiac problems, cleft palate, invaginations in lip, hypodontia
Foetal alcohol spectrum disorder
small head, low body weight, learning difficulties, coordination problems, cleft lip and palate
Neonatal cleft lip/palate management inc surgery details
Special bottle for feeding that doesn’t rely on suckling
Wait until babies are thriving and then surgery for cleft lip (3 months) and cleft palate (6 months).
Cleft lip - make muscles lie horizontally like lip
Cleft palate - nasal epithelium, muscles and oral epithelium closure (3 layers)
Alveolar defect not fixed
Remove any neonatal teeth
Young cleft lip/palate children management
Class 3 incisors due to previous surgery
Dental anomalies - missing teeth, displaced/ectopic teeth, microform teeth, fused teeth, hypoplastic enamel
Poor OH - painful surgery sites, fistulas so poor diet, altered saliva, tongue movement, hard to clean displaced teeth, hospital burnout
Speech therapy and hearing therapy
Speech therapy for cleft lip/palate patients
Nasal speech because of fistulas
Can’t pronounce T sounds etc bc tongue avoids the roof of the palate where surgery was
For all patients
Hearing tests for cleft lip/palate patients
Can get glue ear if the defect affects the middle ear draining through the Eustachian tube. May need to place a tube to drain ear (Grommets), or hearing aid or child can grow out of it w age.
Cleft lip/palate older children management
9-11 years old Fix alveolar defects with grafts to close fistulas, align maxilla so teeth can erupt normally. Unfavorable skeletal growth e.g. class 3 can affect options- may need orthognathic surgery but need to consider previous surgeries, scars and effects on speech.
Any gaps that can’t be fixed with bone grafts may need to be accepted or use restorative dentistry to improve aesthetics.
GDP considerations when managing cleft lip/palate patients
- High caries risk
- Limited access
- Multiple appointments with other health care professions
- other syndromes and complex MH
Bone involved in the TMJ
Bones involved
- Temporal bone (mastoid process, styloid process, external auditory meatus, mandibular/glenoid fossa, articular eminence of zygomatic arch)
- Zygomatic bone
- Maxilla
- Mandible (condyle, mandibular notch, coronoid process, neck, ramus, angle, body)
Muscles of mastication + accessory muscles
MoM
- temporalis (temporal fossa and coronoid process)
- masseter (attaches to zygomatic arch and angle of the jaw)
- Lateral pterygoid (lateral pterygoid plate and inner border of the angle of mandible and articular disc, 2x heads and fuses at the mandible)
- Medial pterygoid (medial pterygoid plate and inner border of the angle of mandible, 2x heads and fuses at the mandible)
Accessory
- geniohyoid (attaches to the chin and hyoid bone)
- digastric (chin, hyoid and mastoid)
- buccinator
Normal movement of the TMJ
- Hinge movement - Rotates in mandibular/glenoid fossa
- Forward and downwards translation
Articular disc inbetween the condyle and glenoid fossa - concave and divides joint into upper and lower.
- Upper = translation movements
- Lower = hinge/rotation
The normal opening is 35-50mm
Reinforced with fibrous articular capsule and ligaments e.g. TMJ ligament which limits posterior and lateral movements of TMJ.