Orthognathic/Craniofacial/OSA Flashcards
Describe APGAR score
Apgar scores of 0-3 are critically low, especially in term and late-preterm infants
Apgar scores of 4-6 are below normal, and indicate that the baby likely requires medical intervention
Apgar scores of 7+ are considered normal (1, 3)
Incidence of CLP per 1000
- Asian 3.2
- Caucasian 1.4
- African 0.43
What gestational age can CLP be diagnosed
16 weeks via ultrasound
What screening tool should be employed for infant with CLP
Echocardiogram
R/o valve disease or great vessel transposition
CLP laterality prevalence
2:1 on left
When does cleft lip (CL) develop
During 3rd-7th weeks
When does cleft palate form?
During 5th-12th weeks
What processes fail to fuse in CL?
CL = failed fusion of medial nasal and maxillary processes
What fails to attach / align in CP?
CP = failed attachment and alignment of levator veli, tensor veli palatini, uvular, palatopharygeus, and palatoglossus muscles
What forms primary palate? Secondary Palate?
Primary palate = premaxila = lip, alveolar arch, palate anterior to incisive foramen
Secondary palate = hard and soft palates posterior to incisive foramen
Rule of ten’s for safe infant anesthesia
- 10 weeks old
- >10lbs
- Hg >10
When is primary lip repair performed?
Advantages for later repair?
10-14 weeks
- More prominent landmarks
- Easier
- Better esthetic outcome
When is CP repair done?
What developmental milestone guides timing?
What are advantages for later repair?
9-18 months
Speech development. If child has mental delay and speech is anticipated much later, than CP repair should be delayed
- Decreased incidence of maxillary hypoplasia
What is incidence of VPI following CP repair?
20% VPI
diagnosed 3-5 years old
When is alveolar grafting performed?
Mixed dentition age 8-11
Canine root 2/3 formed
When is orthognathic surgery performed
If needed it is done age 14-18
When is lip and nasal revision surgery done?
After age 5 and only for severe deformities
What is most common technique for unilateral CL repair?
Millard rotation-advancement technique
- 3 layers
- Orbicularis oris muscle is made to form continous sphincter
- Incisions lie in natural contours
https://www.youtube.com/watch?v=kVZ0vlW3c7Y
When is rhinoplasty done?
6-12 months after orthognathic surgery, if needed. This is because maxillary advacement often improves nasal esthetics.
What can be done during CL repair to lengthen columella or create nasal sill?
C-flap
https://www.youtube.com/watch?v=eZfQXT_A8Jo
Upper facial 1/3 exam
- Female eyebrow form/dimensions
- Superior orbital rim relation to cornea
- Female eyebrows slope upward, peaking about 10 mm above the supraorbital rims
- The superior orbital rims should project about 10 mm in front of the cornea
- Normal nasolabial angle
- Lateral orbital rim relation to cornea
- 100 +/- 10. Greater in females
- 10mm posterior to cornea
- Upper incisor show at rest
- Racial variance on incisor show
- Changes with age on incisor show
- What percent of lower facial heigh is occupied by upper lip?
- Lower lip?
- Ratio of Bizygomatic width to Bigonial width?
- Chin throat angle?
- 5mm Females>males
- Whites show more than > Asians > Blacks
- Decreases with age
- Upper lip 30% lower facial height
- Lower lip 25% lower facial height
- Bigonial width 30% less than bizygomatic width
- Chin throat angle 110
Steiner analysis
- What assesses maxilla position? Normal range
- Mandible position? Normal range
- Max - Mand relationship? Normal range
- What assesses maxilla position - SNA 79-84 deg
- Mandible position - SNB 76-82 deg
- Max - Mand relationship - ANB 4-0 deg
Ricketts Analysis
- What assesses maxilla position?
- Normal range
- What assesses maxilla position? NA - FH
- 86-94 deg
McNamara Analysis
- What assesses maxilla position? Normal range
- Mandible position? Normal range
- Max - Mand relationship? Normal range
- What assesses maxilla position? N perpendicular to A
- Normal range 0-1mm
- Mandible position? N perpendicular to Pog
- Normal range mixed dentition -7mm
- Normal range female -4 to 0
- Normal range male -2 to +2
- Max - Mand relationship?
- Midface length (Condylion to A) - mandible length (Condylion to Pog)
- Normal range mixed dentition 19-21mm
- Normal range female 25-27mm
- Normal range male 30-33mm
Downs Analysis
- Mandibular position reference points
- Normal range
- Similar to what analysis scheme for maxillary AP position
- FH to N-Pog
- 86-94 deg
- Rickets uses FH to N-A point for maxilla
Steiner Facial Type Analysis
- How to assess facial type with Steiner
- Normal range
- Intersection of Mandibular Plane with SN
- 30-34 deg
Panorex findings of Long face
- Vertical growth, mandible rotated open, short ramus height, obtuse gonial angle
Panorex findings of Short face
Long ramus, acute gonial angle, horizontal growth, over-closed mandible, decreased lower facial height.
Growth cessation
- C-spine findings on lateral ceph
- Mature C-spine
- Rectangular shape (instead of triangular)
- Inferior body curved (instead of flat)
Lefort Measurements
- Incision distance above MGJ
- Distance from piriform rim to DPA
- Incision 3-5mm superior to MGJ
- DPA 34mm posterior to piriform
Advantages of interdental cuts between 2s/3s
Advantes of interdental cuts between 3s/4s
2s/3s
- Less chance for root injury (2 single roots)
- Often don’t need ortho to separate roots
- Can manage inclination of incisors
3s/4s
- Larger segment with blood suppy
SARPE
- Indications
- Used when which suture has closed?
- What does expansion start?
- Rate of expansion?
- >10mm transverse deficiency
- Midpalatal suture
- 5-7 days postop
- 0.5mm day
LeFort Complications
- What can cause blindness during LeFort?
- What can be done to minimize bleeding?
- What can limit anterior movement of maxilla?
Blindness
- Skull base fracture
- Optic artery hypoperfusion
- Arterial aneurysm
Bleeding
- Hypotension
- Afrin
- Reverse Trendelenburg
Limited Anterior Movement
- Horizontal fracture through pterygoid plates leaving medial pterygoid m. attached. Manage by separating tuberosity from pterygoid plates
3 reasons for mandibular surgery first
- Unable to place patient in CR for planning purposes (micrognathia, condylar erosion, muscular dystonia)
- Clockwise mandible movement is beyond pure rotation (planning software can’t account for translation)
- Thin maxillary bone (if maxilla is cut and plated first, the plates may weaken during mandibular surgery due to bite blocks)
2 reasons for maxilla first surgery
- Thin ramus, other concerns that make a bad split likely (unstable mandible puts maxilla in wrong position)
- If planning a VRO
Idiopathic Condylar Resorption
Management options
Advantages/Disadvantages
OSA Prevalence
2-4%
What number is abnormal Epworth Sleepiness Scale
Score of 9 or greater
RDI numbers / AHI numbers
Mild
Moderate
Severe
Airway Eval with Lateral Ceph
- List 3 areas
- Average dimensions
- Soft palate length 35mm
- Posterior airway space: 11mm
- Hyoid to Mandibular plane <15mm
Fujita Classification
List 3 types
- Narrow oropharynx: large tonsils/uvula, pillar webbing
- Oral and hypopharyngeal obstruction: flat palate, large tongue
- Hypopharyngeal obstruction: retrognathia, floppy epiglottis, large lingual tonsils
Prevalence of Fujita Classifications
- Percent of OSA with discrete Type II (Oro/Hypopharyngeal)
- Percent of OSA with discrete Type I (Oropharynx)
- 20% discrete Type II
- 10% discrete Type I
