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Oral Board Review Textbook > Orthognathic Surgery, OSA > Flashcards

Orthognathic Surgery, OSA Flashcards

1
Q

What are the indications for orthognathic surgery?

A

When dentofacial deformities cannot be corrected by conventional orthodontic compensation, including growth modification and camouflage techniques as well as for treatment of OSA

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1
Q

What are the approximate AP, vertical and transverse discrepancies that would require orthognathic surgery to correct?

A

-AP: OJ 5 mm or more, or zero to negative value. Molar discrepancy of 4 mm or more
-Vertical: 2 standard deviations from normal, open bite or 2 mm posterior open bite, deep overbite with irritation of tissues, supraeruption of dentoalveolar segment
-Transverse: 2 or more standard deviations from normal. 3 mm or greater unilaterally or 4 mm bilaterally. Need to differentiate between dental tipping

-3 mm or greater of any asymmetry

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2
Q

What are the goals of presurgical orthodontics?

A

-Decompensation of teeth
-Arch alignment and leveling
-Bolton analysis
-Arch coordination
-Final presurgical orthodontic preparation

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3
Q

What are the goals of decompensation of teeth?

A

-House teeth within alveolous
-Maxillary incisors: 102 degrees to SN
-Mandibular incisors 90-95 degrees to mandibular plane

-Class II patients have retroclined upper incisors and proclined mandibular incisors
-Class III patients usually have proclined upper incisors and proclined mandibular incisors

-May require extractions to make space

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4
Q

What are the goals of arch alignment and leveling?

A

-Teeth aligned
-Adjust for tooth size discrepancy (Bolton’s analysis)
-Create divergence of roots for planned osteotomy sites
-Lingual cusps of mandibular posterior teeth should be 1 mm below the buccal cusp
-Palatal cusps of maxillary posterior teeth should be 1 mm below the buccal cusps

-Plunging cusps can create open bites post-op

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5
Q

What is a Bolton’s analysis?

A

-Determined the disproportion of the size of the permanent maxillary and mandibular teeth
-Overall ratio takes the sum of mesio-distal width of 1st molar to 1st molar
-Mandibular / Maxillary
-91.3% is ideal. If less than 91.3%, maxillary teeth are too big
-Anterior ratio (canine to canine) should be 77.2%

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6
Q

What are the goals of arch coordination?

A

-Dental arches should be reasonably compatible with one another at time of surgery to allow for maximum intercuspation post-surgically
-Need SARPE or segmental osteotomy if transverse greater than 5 mm

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7
Q

What are the goals of final presurgical orthodontic preparation?

A

-Need full dimension rectangular steel arch wire that fills the bracket slow (Ball hook)
-No movement of teeth for 4 weeks prior to models
-Passive stabilizing wire
-Surgical hooks (ball hooks)

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8
Q

What anatomical mandible shape supports a vertical ramus osteotomy vs a BSSO

A

-V shaped mandible: IVRO for setback
-U shaped mandible: BSSO for setback

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9
Q

Describe your upper facial third evaluation.

A

From trichion (hairline), to glabella.
Look for craniofacial deformity
Assess eyebrow shape, position and symmetry

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10
Q

Describe your middle facial third evaluation.

A

From glabella to subnasale.
-Look at eyes, nose and cheeks
-Scleral show and flattening of cheek bones/paranasal region may indicate midface deficiency
-Nose, center of lips, middle of chin should fall on true vertical line
-Cheek bone-nasal base lip contour line, evaluates harmony of the structures of midface and paranasal area of lip

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11
Q

Describe your lower facial third evaluation.

A

From subnasale to menton
Also subdivided into subnasale to stomion superius and stomion inferius to menton (Ratio is 5:6)

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12
Q

Describe your transverse facial fifth evaluation.

A

-Outer canthi should coincide with gonial angle
-Medial canthi should coincide with alar bases of nose
-Interpupillary distance should coincide with corners of mouth

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13
Q

What is normal tooth show at repose and smiling?

A

-2-4 mm at repose
-Full crown length smiling (men), 2 mm gingiva (female)

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14
Q

What are potential causes of excessive tooth display at rest?

A

-Short philtrum height
-Vertical maxillary excess
-Excessive crown height
-Lingually tipped incisors

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15
Q

Describe the cheek in a sagittal view.

A

-Lateral orbital rim lies 8-12 mm behind the globe
-The globe projects 0-2 mm ahead of infraorbital rim
-Malar eminence should be 10-15 mm lateral and 15-20 mm inferior to the lateral canthus

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16
Q

Describe normal measurements in Steiner analysis

A

-SNA: 82 (Greater than 82 means maxillary protrusion, less than 82 means maxillary retrusion)
-SNB: 80 (Greater means mandibular protrusion, less means mandibular retrusion)
-ANB: 2 (Class 3 is less, class 2 is greater)

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17
Q

What is Wits appraisal?

A

-AP relationship between maxilla and mandible not influenced by cranium
-Drop a perpendicular line from A point and B point to occlusal plane
-In male, BO 1 mm ahead of AO
-In female AO and BO equal

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18
Q

Describe the holdaway ratio.

A

-Extend NB line to inferior border of mandible
-Measure to incisal edge and pogonion
-Ideal 1:1 ratio (slightly less in females)
-Lower incisor must be in proper position

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19
Q

How can you eval growth on a lateral ceph?

A

-Cervical vertebrae
-Start developing concavity
-This indicates they are past stage 3/4 (growth likely stopped)

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20
Q

Describe your steps in a Lefort I osteotomy.

A

-GA with nasal intubation, discuss permissive hypotension
-K wire
-Full thickness flap, 5 mm of nonkeratinized mucosa
-Expose maxilla (nasal aperture, infraorbital nerve, pterygoid plates)
-Dissect anterior nasal spine
-Make osteotomy
-Lateral nasal wall osteotomies
-Nasal septum
-Pterygoid plates
-Downfracture 60 MAP
-Mobilize
-Splint, remove interferences
-Seat condyles
-Plate
-Suture

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21
Q

What are potential sources of bleeding with a Lefort I osteotomy?

A

-Pterygoid plexus
-PSA
-Greater palatine artery
-Terminal branches of maxillary artery
-Internal maxillary artery (25 mm superior to base of junction of pterygoid plate)

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22
Q

How would you treat a bleed during a Lefort I?

A

-Pressure packing with gauze or hemostatic agent
-Thrombin (Promotes clot formation through activated bovine prothrombin, activates IIA, converts fibrinogen to fibrin)
-Surgicel (oxidized cellulose that binds platelets, negative pH precipitates fibrin)

-Try to identify vessel for cautery
-Consider IR for embolization

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23
Q

How do you treat an anterior open bite after MMF release?

A

-Likely condyles not seated or area of premature bony contact
-Remove fixation
-Check bony interferences
-Ensure passive condylar positioning, replace fixation

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24
How do you treat a palatal mucosa cut/tear in a multi-piece lefort?
-Repair small tear with single suture -Large tear consider replacing maxilla back to original position to avoid avascular necrosis -Local irrigation, cover with non-compressive splint -Formal closure when revascularization is confirmed
25
How do you treat a vertical posterior maxillary wall fracture?
-Check globe for increased pressure -Re-direct fracture with osteotome -Check globe post-op (IOP, visual acuity, proptosis), consider optho consult
26
How do you treat an intra-op midline discrpancy?
-Etiology: Error in work-up, mounting or splint fabrication -Attempt to reposition maxilla using facial midline or dental midline/stable jaw
27
How would you treat decreased maxillary perfusion intra-op?
-Poor capillary refill or purple gingiva -Replace and fixate maxilla to original position -Keep area clean and prevent infection (antibiotics, chlorhexidine) -Consider hyperbaric oxygen
28
How would you treat a post-op nose bleed?
-Pack nose with nasal packing -Consider OR for maxilla take-down and control bleeding -Consider embolization
29
What would you do if the heart rate dropped intra-operatively?
-Likely trigeminocaridac reflex -Stop stretch on maxilla -Anesthesia may need to treat with atropine or glycopyrrolate
30
How would you treat post-op epiphora?
-More common in high Lefort osteotomies due to damage to nasolacrimal system -May see naasoseptal deviation or swelling -May self-resolve in up to 6 weeks -CT scan to r/o source -May require dacryocystorhinostomy or nasoseptoplasty
31
How would you treat a post-op pseudoaneurysm?
-CT angio, IR consult
32
How do you treat nasal septum deviation or buckling?
-Suture septum to the ANS to prevent deviation -Trim cartilaginous septum or crest for buckling -Post-op try to straighten, consider post-op surgery septoplasty
33
How do you treat a post-op infection of a Lefort?
-Imaging, antibiotics, I&D, debridement -If hardware is source, must remove
34
How do you treat hardware failure?
-Replace hardware, consider more rigid fixation
35
How much transverse space can be obtained from dental tipping?
-5 mm -High relapse
36
How much transverse space can be obtained with a segmental lefort?
-7 mm -More posterior expansion
37
Where is most expansion during a SARPE?
-At canines
38
What is a key aspect of a SARPE to allow for expansion?
-Remove bony interference at buttress
39
How much latency is required in a SARPE
5-7 days
40
What is the rate of expansion, how long of a consolidation phase?
-0.5 mm/day -4 months consolidation
41
How do you manage periodontal compromise between central incisors after a SARPE?
-Decrease appliance back a few notches, reduce rate of expansion
42
How do you manage an asymmetric expansion after a SARPE?
-Happens from incomplete release of pterygomaxillary junction on one side -Half of time this corrects itself -May require segmental osteotomy to correct the asymmetry 4 weeks after SARPE
43
How do you manage inadequate expansion after a SARPE?
-Adequate mobilization and removal of bony interferences
44
What is the Hunsuck modification?
-Medial osteotomy does not extend to the posterior ramus -Allows for shorter split, less soft tissue stripping, improved mandibular contour
45
What is the Dal Pont modification?
-Advanced the vertical osteotomy on the buccal cortex between the first and second molar -Allows for greater advancement and more bony contact
46
What is the Epker-Schendel modification?
-Reduced stripping of the masseter and soft tissue of the medial ramus -Cut at inferior border to extend to lingual side, including entire inferior border in the proximal segment -Decreased post-op swelling, hemorrhage and manipulation of neurovascular bundle -Easier repositioning of TMJ, reduction of relapse and more blood flow to proximal segment
47
Describe your BSSO technique.
-Incision over anterior border of ramus, 5 mm non-keratinized tissue cuff -Dissection and exposure of mandible -Medial dissection above lingula, ID mandibular foramen -Make corticotomies with oscillating saw (medial, sagittal, vertical) -Chisel, split mandible -J stripper to remove medial pterygoid attachment -Splint, remove interferences -Seat condyle -Fixate (positional screws)
48
How do you manage a nerve transection during a BSSO?
-Epineural repair with 7/0 non-resorbable suture (nylon)
49
How do you manage a buccal or lingual plate fracture during a BSSO?
-Complete osteotomies -Set to planned occlusion -Fixate fractures with plates and screws (bicortical positional screw can be used for a lingual plate fracture) -Stabilize as planned to new position -If segment is small and attached to periosteum, consider leaving it
50
How is a subcondylar fracture managed during a BSSO?
-Complete osteotomies -Set to planned occlusion -Fixation with plates and screws vs IMF
51
How is a post-op infection managed from a BSSO?
-Review imaging for hardware/screw loosening -Antibiotics, incision and drainage, debride, or hardware removal if needed
52
How is a malocclusion managed from a BSSO?
-Peri-op: Remove fixation, ensure condyles seated and replace fixation -Post-op: Evaluate, consider going back to OR vs close with ortho
53
How is condylar sag managed from a BSSO?
-Manifests as unilateral malocclusion after removing IMF -Remove fixation -Reposition condyle -Reapply fixation
54
How is condylar resorption managed from a BSSO?
-Associated with skeletal class 2 deformities with high mandibular plane (female predilection) -Treat with bite splint therapy and anti-inflammatory medications -More severe cases may warrant synovectomy, costochondral grafting or TMJ replacement
55
How is a non-union managed from a BSSO?
-Re-operation of the site -Freshen bony margins -Remove fibrous tissue -Apply more rigid fixation -Consider bone grafting -Consider period of IMF
56
When should a bilateral intraoral vertical ramus osteotomy be considered?
-Mandibular set-back -Best for V-shaped mandible (divergent ramus pattern) -Less likely to have paraesthesia (both short and long term) -Thin mandible with little marrow space -Pt with symptomatic TMD
57
What are potential consequences of an IVRO?
-If CCW movement is planned, proximal end of distal segment will rotate inferiorly and may pull on proximal segment -Can create splaying of proximal bony segment and create fullness in mandibular angle
58
What is the technique for an IVRO?
-Incision over anterior border of the ramus into the mandibular vestibule -Full thickness flap exposing the lateral ramus and inferior border up to the sigmoid notch -Bauer retractors into the sigmoid notch and along inferior border of mandible -Identify the antilingula (anterior limit of osteotomy) or 7-10 mm anterior to posterior border -Make vertical cut using oscillating saw blade -Make superior osteotomy last as risk for bleed from masseteric artery -Develop a subperiosteal pocket on medial aspect of mandible to accept the overlapping segment -Manipulate proximal segment laterally -Trim excess inferior portion of bony proximal segment -Establish occlusion with MMF x6 weeks -If segments are passively positioned and in approximation, rigid fixation with two or three screws can be completed through trochar
59
How is an infection managed s/p IVRO?
-Antibiotics, I&D, debridement as needed
60
How is bleeding managed during an IVRO?
-Most likely from internal maxillary artery branches (massetric branch at sigmoid notch; 8 mm above sigmoid notch and 25 mm from anterior border of ramus) -Direct pressure with gauze -Consider hemostatic agents -Identify bleeding vessel, consider hemoclips -If uncontrolled, consider embolization
61
How is a displaced proximal segment managed during an IVRO?
-Distract mandible anteriorly and reposition -Evaluate for medial bony interferenced and reduce as necessary
62
How is distraction of the condylar segment managed during an IVRO?
-May occur early in treatment or weeks after surgery -Aggressive elastic traction should be attempted -May require revision and placement of fixation/wire
63
How is an inadvertent subcondylar osteotomy managed during an IVRO?
-Place pt in IMF x6 weeks -Complete surgery after establishment of bony union
64
What is the procedure called to advance airway during genioplasty, what must be included in the osteotomy?
-Anterior mandibular osteotomy with genioglossus advancement -Need to include the genial tubercles
65
Describe the surgical technique of a genioplasty.
-Incision is half the distance between the vestibule and the wet line of the lip from canine to canine -Incise through mucosa, submucosa, through mentalis then to bony mandible -Subperiosteal dissection, identify mental nerves bilaterally -Mark midline of chin -Make osteotomy (5 mm below foramina and 5 mm below apicies of teeth), also need 10 mm above inferior border of mandible at midline -Bony chin mobilized and repositioned (bone plate) -Closure in layers (mentalis to prevent ptosis of the chin), then mucosa
66
How is chin ptosis managed s/p genioplasty?
-Avoid complication: ensure reapproximating the mentalis and aggressive soft tissue dissection -Reopen wound and reapproximate mentalis -Placement of pressure dressing
67
How is a malposition of the chin managed s/p genioplasty?
-Remove plate and realign
68
How are injured root apicies managed s/p genioplasty?
-Observe, possible root canal in future
69
How is a nerve injury managed s/p genoiplasty?
-Ensure dissection is 5-6 mm away from mental formaina -Epineural repair with 7/0 suture for observed transection
70
How is a malunion managed s/p genioplasty?
-Debride interposing fibrous tissue and reposition with new hardware -Consider bone grafting
71
How are infections/hardware failure managed s/p genioplasty?
-I&D, antibiotics, debridement, remove hardware possibly -Hardware failure: Remove hardware and replace if no evidence of union
72
What is the hierarchy of stability in orthognathic surgery?
-Maxilla up -Mandible forward -Maxilla forward -Maxilla up/mandible forward -Maxilla forward/mandible back -Mandible back -Maxilla down -Maxilla wider
73
Who are the members of the cleft lip/palate team?
-Patient care coordinator -Pediatrics/primary care/geneticist -Surgeon (OMFS, plastic, ENT) -Pediatric dentist -Orthodontist -Speech pathology -Audiology -Psychology -Social work
74
What is timing of orthognathic surgery?
-When growth is complete (same as normal) -Before secondary nasal revision
75
What are treatment planning considerations (in diagnosis) and how is this translated in planned surgery?
-Primary deficiency is maxillary hypoplasia -Try to address this, limit mandibular setback -May need to do distraction osteogenesis to achieve desired outcome
76
What are intubation considerations in a cleft orthognathic surgery procedure?
-Patient may have had a velopharyngeal flap procedure -Need to ensure atraumatic placement of nasal tube through a lateral port of the pharyngeal flap -Can pass red rubber catheter for visualization and safe pull-through -Endoscopic or fiberoptic guidance -NPA to guide bougie and pass ETT along bougie
77
What are incision design considerations in a cleft orthognathic surgery procedure?
-Want to maximize blood supply -Shortened circumvestibular incision leaving a large buccal soft tissue pedicle -An anterior midline pedicle can be left with a vertical incision at midline and two lateral vestibular incisions
78
Where is most of the blood supply to the mobilized maxilla derived from in a cleft orthognathic patient?
-Palatal tissues
79
What are considerations of osteotomy and down fracture in the cleft orthognathic patient?
-Greatest areas of buttressing in the maxilla are pyriform and pterygomaxillary buttresses. Care must be taken when completing the osteotomy -Unfavorable fracture to skull base or orbit from poor osteotomy/seperation. -Too much pressure can lead to fracture of thin grafted alveolar bone and transverse instability
80
How is the nasal floor managed after downfracture for a cleft orthognathic?
-Examine for: Residual oronasal fistula, septal deviation, enlarged inferior turbinates, alar support -Close any residual fistula, place any bone graft needed -Pt may need septoplasty -Inferior turbinectomy can be considered at this juncture as well -Take time to stretch soft tissue to allow for planned moves
81
Describe fixation and bone grafting considerations in cleft orthognathic patient?
-Likely need bone graft because you want good bony contact -Rigid fixation with largest/strongest system
82
Describe rigid external maxillary distraction technique/principals.
-Orthodontist makes an intra-oral splint that attaches to orthodontic appliances with extra-oral extensions -Lefort I osteotomy the same -Adequate mobilization is critical -Cranial halo placed with an external adjustable distraction screw system. A rigid down-rod is attached to the halo which is used to attach wires to the extra-oral component of the splint -Latency 5-7 days, activation and consolidation
83
What are the advantages of rigid external maxillary distraction?
Advantages: -Adjustable vector of distraction throughout activation phase -Does not require secondary surgery for removal Disadvantages: -Psychosocial aspect of wearing a large extra-oral appliance -Does not offer retention and requires use of reverse ull headgear after removal
84
What are the advantages/disadvantages of internal maxillary distraction?
Advantages: -No halo device needed -Reverse pull head gear not necessary (leave device in place with removal of activation arm Disadvantages: -Unidirectional vector that cannot be altered -Second surgery required for removal
85
What is OSA?
-A sleep disorder characterized by obstructive apneas and hypopneas caused by collapse of the upper airway during sleep
86
What is central sleep apnea?
-The absence of respiration associated with an absence of respiration effort
87
What is PSG?
Polysommography is a diagnostic test used for the evaluation of sleep disorders. -Includes EEG, EOG, EMG, ECG and pulse ox with or without video recording of the subject
88
What is apnea and hypopnea?
-Apnea: Cessation of airflow at the nostrils and mouth for at least 10 seconds -Hypopnea: Reduction in airflow resulting in a drop in oxygen saturation followed by arousal
89
What is the apnea/hypopnea index?
-Average number of apnea and hypopnea events per hour
90
What are Cheyne Stokes Breathing?
-Breathing pattern marked by crescendo-decrescendo changes in airflow and respiratory effort that often ends with apnea (typical in central apnea syndrome)
91
What is Muller's maneuver?
-Inhalation with nasal passages occluded and mouth closed with an endoscope inserted through one nostril to observe the location of airway collapse
92
How is OSA classified?
Fujita Classification: -Indicates level of obstruction identified by nasopharyngoscopy in conjunction witha Mueller's maneuver during sleep induced nasopharyngoscopy. Useful guide to determine surgical interventions may be helpufl
93
How is OSA graded with AHI values?
-Normal: 0-4 AHI -Mild OSA: 5-15 AHI -Moderate: 15-30 AHI -Severe: >30 AHI
94
Describe Fujita Type I-III.
-Type I: Upper pharynx to include the palate, uvula, and tonsils -Type II: Upper and lower pharynx -Type III: Lower pharynx to include the tongue base, lingual tonsils and supraglottic region
95
What are the stages of sleep?
N1, N2, N3 and REM (phasic/tonic).
96
What is the pathophysiology of OSA?
-Increased sympathetic tone tone leads to autonomic arousals -Hypoxia leads to sleep fragmentation and restriction -Hypoxia followed by oxygenation can lead to free radicals and endothelial damage (hypoxia repurfusion injury), also activation o f PMNs and inflammatory mediators -Leads to chronic inflammatory state -Most common in males aged 18-60
97
What are medical co-morbidities associated with OSA?
-CV: HTN, arrhythmias, CHF -Neuro: Stroke, parkinsons, seizure -Endocrine: DM -Psychatric: Cognitive function, depression -Pulmonary: Pulmonary hypertension -Digestive: Acid reflux -Other: Decreased wound healing, headaches, immune system impairment
98
What subjective screening tools can be used in the diagnosis/work-up of OSA?
STOP BANG questionnaire, Epworth Sleepiness Scale
99
What is the STOP BANG questionnaire?
-Snore loudly -Tired or fatigued -Observed apneas -Pressure (HTN) -BMI >35 -Age >50 -Neck circumference >16" -Gender (male) 1 point each, 5-8 points high risk
100
What is the Epworth sleepiness scale?
- 0-3 scale of chance of dozing during situations - 8 situations: Sitting/reading, watching TV, sitting in public place, passenger in car, lying down to rest, sitting and talking, sitting after lunch, in car while driving stopped in traffic 11-24 excessive daytime sleepiness
101
What are pertinent physical exam findings with OSA?
-BMI >30, neck/waist circumference -Fat deposition in uvula, tonsils, tongue, lateral pharyngeal wall -Neck circumference bigger than 17 (16 in female) -Decreased FRC
102
Describe the airway examination in an OSA patient.
-Look at occlusion (clinical and lateral ceph) -Class II from retrognathia may have narrow posterior airway space -Macroglossia -Elongated uvula/soft palate, nasal septal deformities, enlarged turbinates, tonsillar hypertrophy -Evaluate mallampati score
103
What is nasopharyngoscopy and how is it used in OSA?
-Use of flexible fiberoptic laryngoscope to examine the lumen of nasal passages, oropharynx and vocal cords -Used with Mueller's maneuver to identify potential sites of obstruction, can be performed supine or sitting positions -Can be performed in office setting
104
What is drug induced sleep endoscopy (DISE) and how is it used in OSA?
-Nasopharyngoscopy performed on a patient undergoing sedative induced sleep -Anesthetic agents blunt negative pressure reflex and mimic conditions of REM sleep -Usually performed in OR (may need to take over airway) -Can identify specific areas of collapse in the pharynx and direct site specific surgical intervention
105
What is polysomnography and how is it used in OSA?
-Full night, in lab PSG is considered gold standard in diagnosis -Negative result should be viewed with skepticism with patient's with high suspicion of OSA (difficult to fully translate info due to environment)
106
What is home sleep apnea testing?
-High sensitivity in appropriate patients, sleep study done at home -Useful in patients suspicious of moderate to severe sleep apnea -Often underestimates AHI
107
How is posterior airway space (PAS) measured on a lateral ceph?
-A line that bisects B point and gonion through the posterior airway space. -A PAS less than 11 may indicate base of tongue obstruction (pt therefore a poor candidate for upper airway surgery)
108
What does a decreased posterior airway space correlate to?
-PAS less than 11 -May indicate base of tongue obstruction -Patient would be a poor candidate of UPPP
109
How is the length of the soft palate measured on a lateral ceph?
-P to PNS -Length of soft palate measured from the posterior nasal spine to the tip of the soft palate -Normal measurement is 37 -Increased length associated with OSA
110
How is the position of the hyoid measured on a lateral ceph?
-H to MP -Distance of the hyoid bone to the iinferior border of the mandible along a line perpendicular to the mandibular plane angle -Normal is 15 mm -An inferior positioned hyoid is indicative of a longer airway and UPPP failure
111
How can a CBCT be used in the diagnosis of OSA?
-Can examine airway in axial, coronal and sagittal planes -Can allow for volumetric 3D reconstruction of the airway
112
How can MRI be used in diagnosis of OSA?
-Can be done under sedation to detect site of obstruction -Can give anatomic detail of the soft tissues surrounding the airway and can detect fatty deposits around the pharynx
113
What are non-surgical therapies for OSA management?
-Weight reduction: Can reduce severity of OSA, lower pressure of CPAP, can offer resolution. -Oral appliances
114
Describe oral appliances in the management of OSA.
-Can be used for patients with mild-moderate OSA -Can be used in severe OSA as adjunct to CPAP -Adverse effects: Retroclined maxillary teeth, proclined mandibular teeth, bruxism, dry mouth, TMJ -Need q6 month dental follow-up x1 year followed by yearly
115
What is the Stanford Protocol for OSA management?
-Surgical approach aimed at standardizing OSA procedures among surgeons -Not a cookbook approach, merely classifies as Phase I or Phase II of where surgery is performed, not timing of surgery -Surgery should be addressed to the site of obstruction
116
What are Phase I surgeries for OSA and where is the obstruction addressed?
-Nasal obstruction: Septoplasty, turbinectomy, alar collapse, valve deformities -Retropalatal Obstruction: UPPP with tonsillectomy -Retrolingual Obstruction: Genioglossus advancement
117
What are phase II surgeries and where is the obstruction addressed?
-MMA (Global airway surgery) -Tracheostomy (100% success rate)
118
What are considerations of MMA for OSA?
-Patient may not have a dentoskeletal malocclusion (may not require ortho) -Need to counsel patient on change in appearance -May need arch bars during/after surgery -Maximize movement (10 mm), may need CCW movement -May have had previous soft tissue surgeries, may be difficult to get full movement -High relapse, consider bicortical screws/heavier plates to reinforce osteotomies -Consider bone grafts -Post-op ICU with continuous pulse ox

Oral Board Review Textbook (26 decks)

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