final Flashcards
AA nn fiber
mylienated, position/fine touch
AB fiber
mylienated, proprioception
AD fiber
thin myelin, superficial pain/temp
C fiber
unmyleinated, deep pain/temp
Levels ABC nn testing
level A testing tests
Two Point Discrimination Testing
Level A Test - This test is used to determine the response of the slowly adapting larger myelinated fibres (A-α)
The patient’s ability to discriminate between two points is measured using caliper with increasing D
WNL; 6mm
Brush Stroke Directional Discrimination
* This test is used to determine the response of the slowly adapting larger myelinated fibres (A-α) and A-β myelinated axons.
* The sensory modalities for these receptors are vibration, touch and flutter.
use of camel brush
Level B testing
contact detection
LEvel C testing
pain/temp
Surgical Nerve Repair.. How you do it?
Surgical Nerve Repair.. How you do it? How you put the segmented nerve back together?
8-0 nylon epineural
Graft if not tension free (sural or greater auricular)
Conduits up to 5 mm spacing, option for decell nn allograft
best nn for graft
Sural (BEST)
or greater auricula
seddons class for nn injury
neuropraxia, axonemtesis, neurometesis
neuropraxia
Neurapraxia: It is a Conduction block resulting from mild insult to nerve trunk.
Temporary paralysis of a nerve caused by lack of blood flow or by pressure on the affected nerve with no loss of structural continuity.
There is no axonal degeneration, and sensory recovery is complete and occurs in a matter of hours to several days.
The sensory deficit is usually mild and characterized by paresthesia
axonemetis
Neural tube intact, but axons are disrupted.
Axonotmesis: It is a more severe injury as compared to Neurapraxia. Afferent nerve fibers undergo degeneration, but the nerve trunk is grossly intact.
Sensory recovery is good but incomplete.
The period of recovery is related to the rate of axonal regeneration and usually takes several months.
The sensory deficit is characterized by severe parasthesia
neurotmesis
Neurotmesis: This is the most severe kind of nerve injury where complete disruption of the nerve takes place.
The sensory deficit is characterized by anesthesia.
Injuries are likely permanent without repair
The neural tube is severed
sunderlands class and relation to seddon
I: neuropraxia
II-IV: axonotmesis
V: neurotmesis
What’s in the incident of Inferior alveolar nerve injury vs Lingual nerve injury (Know the average?)
What’s in the incident of Inferior alveolar nerve injury vs Lingual nerve injury (Know the average?)
IAN - 1.2%
Lingual - 0.9%
How do you injury inferior alveolar nerve and Lingual nerve? In another word, what procedure or
movement you have to do to CUT and mess it up? Dude, you are the one with the 15 blade so don’t tell
me “I don’t know what happened”.
Injure lingual cortex, Pathology, Local anesthetic, flap, 3rd molar extraction (MC) , implants, RCT
canal usually buccal and inferior to roots (IAN)
There are several criteria need to meet before performing Secondary Alveolar Bone grafting. (Slide 89/93?)
what does this provide
Before canine eruption (1/2-2/3 root formation)
Age 9-11
3 layer closure (nasal, bone graft, oral layer)
- Provide bone for the eruption and/or orthodontic repositioning of
teeth
- Provide bone for the eruption and/or orthodontic repositioning of
- Closure of oro-nasal fistulas
- Support and elevation of the alar base
- Stabilization of the pre-maxilla in bilateral cases
- Provide continuity of the alveolar ridge
VPI Velopharyngeal Incompetence. What is it? Why do you need to do Pharyngoplasty procedure?
(Slide 83/93)
Cannot separate oral and nasal cavities during swallowing and speech with velopharyngeal mechanism. Hypernasality.
Recommended to resolve
velopharyngeal incompetence after patients prove unable to
achieve significant speech improvements through speech therapy
alone.
* Other requirements to qualify for
* The goals of surgery are to eliminate the symptoms of
hypernasality and eliminate audible nasal emissions without
causing complete obstruction of the velopharyngeal port,
allowing for nasal breathing and nasal resonance.
* The pharyngeal flap has been the most common method for secondary management of VPI . the surgery include a short and immobile or easily fatigued palate.
Age 6-9
What’s special about Palatoplasty? There are layered closure. What are the layers?
what time is it done?
11-12 months
Nasal, muscle, oral
palatoplasty techniques
- Various Techniques available
- Von Langenbeck Technique and it’s modifications
- Wardill Technique
palatoplasty scarring
Trend is towards less scarring and less tension on the palate.
* Scarring of the palate may cause impaired midfacial growth
(Alveolar arch collapse, midface retrusion, malocclussion)
* Facial growth may be less affected if surgery is delayed until 18 -24
months, but feeding, speech, socialization may suffe
how can midface hypoplasia be tx
lefort 1
OMFS timeline for CLP pts
3-4 months: Primary lip closure
11-12 months: Primary palate closure
6-9 years: Pharyngoplasty
9-11 years: Alveolar bone grafting
14 years: Orthodontics
18 yrs: orthognathic
….
What is the most commonly used surgical technique to close a cleft lip….
Millard’s Rotation Advancement Flap
Left lip develops when there is a failure of fusion of what fetal structures?
Medial nasal process and maxillary process
Anatomical classification of the CLP is based on?
Location, completeness, extent
Incidence of CLP in USA according to different ethnic groups are?
Native North American, Asians, Caucasians, Africans (NACA)
in this order