JDV 2019 #3 Anatomy of the Brachycephalic Canine Hard Palate & Tx of Acquired Palatitis Using CO2 Laser; Regalado Ibarra, Legendre Flashcards
Palatal abnormalities common in some breeds- ie boxers, bulldogs-
Prominent palatal rugae, increased depth of rugae= entrapment of debris-plaque, food, hair –> acquired palatitis or granulomatous lesions
Cause of excessive prominence & indentation of palatal rugae in brachycephalic breeds
Maxillary shortening without adjustment of soft tissue structures
Space b/w abnormal folds is wider at the bottom & narrow at top thus entrapment
DDx for ulcers on the hard palate
Oral trauma, FB reaction, acquired fistula, neoplasia (T cell lymphoma, melanoma), chemical/electric burns, CCUS, uremia, immune mediated (pemphigoid disorders, lupus eruthematosus), EOG
Advantages of CO2 laser tx
high absorption coefficient of water, precision cutting, hemostatic effect, reduction in pain/inflammation, wound sterilization, immed moderate tissue contraction, useful for cutting or vaporization of tissue
Key descriptive terms for palatal rugae
Main ridge- numbered palatine ridges from rostral to caudal (vary b/w 6-10)
Incisive papilla
Median Raphe- midline palatine raphe, overlies the median palatine suture, may be complete, incomplete or absent
Ridge angles- anteriorly forward, horizontal-perpendicular, or posteriorly backward in relation to median raphe
Shapes of rugae- straight, irregular/wavy, forking/curved, or forming circular islands.
Crest or ridge- tallest area
2 aspects of the fold- face (rostral) and backside (caudal) which can be concave, convex or sloping
Embryologic origin of the primary & secondary palate=
First pair of pharyngeal arches
From this, the dorsal maxillary prominences extend bilaterally
Then the MX prominences fuse to form the primary palate (rostral portion of palate). From the same MX prominences bilateral palatine shelves emerge expanding medially and mergine at midline forming the secondary palate. The secondary palate is initially only membrane that then ossifies to form hard palate.
What are the 3 osseous components of the palate?
- Rostral paired palatine process of the incisive bone
- central palatine process of the MX bone
- caudal horizontal plate of the palatine bone
Blood & nerve supply of the palate & pathway
paired major palatine arteries, branches of the maxillary arteries. Similarly innervated by the major palatine nerve a branch of the maxillary nerve.
Palatine bundle or plexus travel from the pterygopalatine fossa through the palatine canals to emerge onto the hard palate by major palatine formaina then run rostral in the palatine grooves
Authors’ observations of when/where palatitis lesions are more common
folds are more than 5mm depth
middle section between the palatine raphe and lateral border
between incisive papilla and MRg 1,2,3 and 4
Goal of CO2 laser therapy for palatal rugae
- Reduce the fold depth by inducing a zone of contraction at the face and backside of each fold. (Continuous wave laser beam approx 2mm dorsal to the valley produce 1.24-1.5mm of tissue contraction. Multiple passes (rastering) may be necessary)
- Debridement of granulation tissue at the bottom of folds by vaporization (incr fibrosis, destroy bacteria, protective coagulum)