100. Palate Flashcards
differentiation of the nasal and oral epithelium
nasal: pseudo stratified ciliated columnaroral: stratified squamous
what bones make up the hard palate
palatineincisivemaxillary
blood supply to the palate
maxillary artery—major palatine artery that travels through major palatine foramen (feeds hard palate)maxillary artery–minor palatine artery (feeds soft palate)
innervation of palate
major palatine branch (hard palate) and minor palatine branch (soft palate) of the maxillary division of the TRIGEMINAL NERVE (sensory information)motor comes from glossopharyngeal (9) and vagus (10)
muscle responsible for elevating the caudal soft palate to protect the nasopharynx during eating, swallowing, or vomiting
levator veli palatine muscle
two functions of the soft palate
- prevents aspiration by elevating the caudal soft palate to protect the nasopharynx during eating, swallowing, or vomiting2. stimulates sensory nerves to help trigger swallow mx
typical side of unilateral cleft lip and hard palate clefts
unilateral cleft lips: often left sided with or without defects in the secondary palatehard palatal defects: midline usually associated with soft palate cleft
at what stage in gestation/fetal development can intrauterine stress or insult result in cleft defects
25-28th day in dogs
ideal age for surgical repair of a congenital cleft palate
3-4 monthstoo young and the tissues are too friable and delicatetoo old and the defects are too largebest chance to repair is at FIRST surgical intervention
surgical goals of closing cleft defects
–tension free (two layer, closure not over the middle of defect)–well vascularized–separation of oral and nasopharyngeal mucosa
recommended length of flaps created to close palatal defects
1.5 times larger than the defect itself
techniques for defect repair
- simple sliding procedures (rarely done bc no underlying support)2. local advancement, transposition, rotation flaps from labial or buccal mucosa +/- tooth extraction3. overlapping flap technique4. medially positioned flap technique (soft vs hard palate)5. split palatal U flap technique (caudal defects)6. prosthetics—temporary or permanent palatal obturators, titanium plate7. distant axial pattern flaps (angularis oris, caudal auricular, superficial cervical)8. free tissue transfer (auricular cartilage)9. tongue flap
if repair fails, how long should you ideally wait before next attempt
wait until all healing has ceased ~4-8 weeks
which is reported to be more reliable to repair a midline hard palate defect: the overlapping flap technique or the medial positioned glad technique
overlapping flap technique is more reliable bc with the medially positioned flap technique the suture line is over the defectalso a lateral oronasal fistula may result with a medially positioned flap technique
best example to use a labial based mucoperiosteum flap
oronasal fistula repair from previous dental extraction or severe dental disease
common side effect with palatal prosthetic obturators
halitosis
factors leading to dehiscence
–poor preservation of the blood supply–too much tension–inadequate tissue mobilization–traumatic tissue handling or from initial injury–inadequate flap size–did not close in two or more layers–poor suture or needle choice
airway resistance met in a normal dog
75-80% NOSE15-20% lower airways5% larynx
breathing pattern assessed by tidal breaking flow volume loops were consistent with……..
FIXED upper airway obstruction in brachycephalic dogs
poiseuille’s law
increased resistance due to decreased airway radiuslaw = Q=( pi(pressure change) r ^4)/8 nLQ= flowr = radius of airwayn = viscosity of gasL - length of airwayFLOW IS PROPORTIONAL TO RADIUS TO THE FOURTH POWERincrease radius, increase flowflow is inversely related to resistanceincrease flow decrease airway resistance resistance is inversely related to radiusincrease radius decrease airway resistance
pathophysiology changes in response to upper airway obstruction or increased resistence
- hering breuer reflex (increase vagal stimulation to control resp rate and depth–muscle contract longer, prolonging inspiration)2. decr PaO2 and incr PaCO2 chemical feedback to increase respiration effort (previous studies of laryngeal paralysis show chronic hypoxia but not hypercapnia)3. noncardiogenic pulmonary edema4. GI signs (>80-90%) brachycephalic dogs have GI signs
concurrent cardiac abN common in BCAS english bulldogs
pulmonic stenosis
tracheal diameter to thoracic inlet ratio in normal vs brachy breeds
english bull dogs 13% (0.13)nonbrachy breeds 20%abN if < 16% (0.16)
proposed level of planned staphylectomy
- mid to caudal border of palatine tonsil2. tip of epiglottis
surgical options for repair of an elongated soft palate
- cut and sew2. bipolar VSD3. CO2 laser4. fold palatoplasty
