Chapter 87 Soft Tissues of the Oral Cavity Flashcards
What is meant by the following:
Oral cavity
Oropharynx
Oral cavity proper
Oral vestibule
Oral cavity: Area bounded by lips, hard palate, tongue/underlying mucosa
Oropharynx: Area bounded by soft palate, root of tongue and pharyngeal wall
Oral cavity proper: Area bounded by dental arcades
Oral vestibule: Area/potential space between teeth and lips
List thethree most common oral tumours in dogs
And cats
Dogs: Malignant melanoma > SCC > Fibrosarc
Cats: SCC > Fibrosarc > Lymphoma
What nerve provides motor innervation to lips
And sensory
Motor: Facial n (VII)
Sensory: Trigeminal n (V)
What is main arterial supply to upper and lower lip?
Upper lip:
- Infraorbital artery rostrally (from maxillary artery)
- Superior labial caudal half (from facial artery)
Lower:
- Inferior labial artery caudally (from facial artery)
- Middle and rostral mental arteries rostrally (from inferior alveolar, from maxillary)
In dogs, the facial artery is a terminal branch of the external carotid artery and is approximately 3 cm long and 1.5 mm in diameter. It arises at the angle of the mandible 1cm from the lingual artery and gives rise to multiple terminal branches. The facial artery is surrounded by the masseter muscle dorsally and laterally, the digastricus muscle ventrally and the styloglossal muscle medially. The facial artery terminates in the face as multiple labial arteries. The facial artery bifurcates into the inferior labial artery and superior labial artery. The angularis oris artery branches ventrally from the superior labial artery and courses rostrally and ventrally. The superior labial artery anastomosis with the terminal branches of the infraorbital artery, the lateral nasal artery and rostral septal branches of the infraorbital artery.
Label the diagram
General view of the oral cavity of the dog.
1, Vestibule;
2, canine tooth;
3, hard palate;
4, soft palate;
5, tongue;
6, sublingual caruncle;
7, palatoglossal arch;
8, palatine tonsil;
9, frenulum;
10, philtrum.
Label the diagram
Which salivary gland(s) empty into the oral vestibule?
Parotid and zygomatic
What are the three ‘geogrphical’ parts of the tongue
Root: Anchors to oropharynx
Body: From root and along attachment of frenulum
Apex: Distal free portion
What are the mucosal ridges either side of the lingual frenulum called?
What is their significance
Sublingual fold
Ends at sublingual caruncle which is where sublingual ducts course and open
What are the three extrinsic muscles of the root of the tongue
What is their origin and insertion:
What nerve controls their movement?
-
Styloglossus (three subdivisions)
- Origin: Stylohyoidbone
- Insertion: Spanventral apspect of tongue
-
Genioglossus
- Origin: Medial aspect of each mandible, immediately caudal to symphysis
- Insertion: separates into three bundles as it fans caudodorsally
- Rostral portion of ventral tongue (vertical bundle)
- Ventral region of caudal tongue (oblique bundle)
- Caudal third of tongue (straight bundle)
-
Hyoglossus
- Origin: Basihyoid bone
- Insertion: Caudal 2/3rds of tongue
Hypoglossal nerve (CN XII)
Label the diagram
How are the intrinsic muscles of the tongue classified (re units of fibre)
The intrinsic muscles are responsible for protrusion of the tongue. Which nerve controls motor function?
- Superficial longitudinal
- Deep longitudinal
- Transverse
- Perpendicular
Hypoglossal nerve (CV XII)
N.B. Hypoglossal is a somatic only CN
What is the central tubelike structure of the tongue called
Lyssa
(muscle, fat, sometimes cartilage)
Function unclear
What is the epithelium of the tongue
Cornified squamous
NAme the 5 papillae of the tongue.
Which are gustatory (i.e. tastebuds?)
FUn VALhalla FOLk
cant taste
FILo CONtaining pastry
Gustatory:
- Fungiform
- Vallate (means raised edge)
- Foliate
Non-gustatory
- Filiform
- Conical
What is the implication of ligation of one side of lingual artery
What is lingual a. a branch of
None as lots of anastomoses throughout parenchyma
Lingual a. is a branch of external carotid
What vein does lingual vein drain into
(Linguo) facial
What are the muscles of the soft palate (5)
- Tensor veli palatini (opens eustachean tube btw)
- Levator veli palatini
- Palatine
- Pterygopharyngeal
- Palatophryngeal (extend laterally and become palatopharyngel arches)
Which nerves control the muscles of the palate?
Glossopharyngal (IX) and vagus (X)
What is the main blood supply to the soft palate Bramch of what artery?
Minor palatine arery, branch of maxillary
How many tonsils does the dogs have (and what are they?)
And cats
Dogs have 4:
- Paired palatine tonsils
- Single lingual tonsil (not grossly appreciable)
- Single pharyngeal tonsil (roof of nasopharynx)
Cats have 6:
- In addition to above, paired paraepiglottic (craniolateral to base of epiglottis)
What is blood supply to palatine tonsis?
Tonsillar artery (branch of lingual artery!)
What LNs do tonsils drain into
And more generally speaking - which LNs shoudl be checked with oral cavity neoplasia
Mandibular and medial retropharyngeal
Mandibular, medial retropharyngeal, and parotid, they drain into superficial cervcal so check that too. Check bilaterally too as vessels of head and neck can cross midline
What is another owrk for the cricopharyngeal stage of swallowing
Pharyngooesophageal
What nerves provide sensory and motor to muscles of mastication, soft palate and tongue
V
VII
XII
Which nerves conrtrol pharyngeal phase of swallowing?
IX and X
What pre-op considerations with oral problems
- Excisioon of biopsy tract
- Difficult intubation - have airway stuff/trach tube stuff ready
- Airway protection - cuffed tube of appropriate size and gauze + suction before removal
- Pharyngostomy tube?
- Feeding tube
- Mouth gag (not spring loaded)
Why shoudl spring loaded mouth gag not be used (esp cats)
Can occlude maxillary arteries –> blindness and neuro deficits
What breed gets tight lip syndrome
3 options for management
Shar pei (only!)
- Inscise lip mucosa at gingival margin
- Excise segment of skin on chin to pull lip margin ventrally
- Deepen rostarl and lateral vestibule
What 3 lip tumours have been remorted in cats
SCC, fibrosarc and MCT
What is met rate for canine oral malignant melanoma
And non-tonsillar SCC
And SCC in cats
Malignant melanoma: 12.9 - 59%
SCC: 0 - 37.5%
SCC in cats: 31%
What is ankyloglossia
Which breed
Tongue tie
Anatolian shepherd
What is second most common place for calcinosis circumscripta?
What % of cases occured here?
Tx:
Tongue (23%)
(hind feet most common)
Tx:
Only if clinical –> excision
How is juvenile oral papillomatosis treated
And if adult
Wait 4-8 weeks - usually resolves
If adult - look for immunosupression. Dont excisie - liekly to come back.
Can try azithromycin and recombinant vaccine
DDX for Burmese cat with pawing at mouth etc but no lesions to be found
Tx?
Feline oral pain syndrome
(precipitated by tooth eruption, oral lesions, environmental anxiety)
Tx: Pheno
What are the three most common oral sites of neoplasia in dogs
And in cats
Dogs: Gingiva > tonsils and lips
Cats: Gingiva and tongue
What % of feline oral tumours does SCC make up
70 - 80%
(61% of lingual tumours)
What dog breeds are at risk of oral malignant melanoma?
And SCC
Maligant melanoma: Pigmented tongues; Chow chow, Shar Pei
SCC: White haircoat; Poodles, Lab, Samoyed. Females
List 2 non-neoplastic ddx for oral lesion in cat
- Eosinophilic granuloma
- Plasmacytic stomatitis
List 3 environmetal risk factors for development of feline oral SCC
- Fed mainly canned food diet
- Regular canned tuna
- Wearing flea collars
What % of malignant melanomas are amelanotic
33%
What % of canine lingual neoplasia is malgnant
Almost all
(64 - 93%)
For ligual tumours managed by excision, what was met rate and MST?
Malignant melanoma
SCC
Malignant melanoma:
- 29% mets
- 241d MST
SCC
- 10-14% mets
- 216d MST
What is recommended margin for lingual tumur
What was recurrence rate in dogs undergoing glossectomy
>2cm
28%
Define the different types of glossectomy
- Partial glossectomy: excision or amputation of any portion, or all, of the oral (free) tongue rostral to the frenulum.
- Subtotal glossectomy: removal of the entire free tongue and a portion of the genioglossus muscles, geniohyoid muscles, or both, caudal to the frenulum.
- Near total glossectomy: resection of > 75% of the entire tongue.
- Total glossectomy: Amputation or excision of the entire tongue
What % of tongue resection is tolerated in dogs without need for any management modification
50%
How can dogs with oral dysphagia be assisted
Raise bowl, deep bowl
(wont help for pharyngeal or cricopharyngeal dysphagia)
List the three “classifications” of things causing dysphagia
-
Structural congenital abnormalities
- Ankyloglossia
- Palate defect
- Macro-/microglossia
- Tight lip syndrome
- Congenital hyoid bone abnormalities
-
Space occupying masses
- Pharyngeal sialocoele (or lingual)
- Thyroglossal cyst
- Abcess
- Neoplasia
- Enlarged LN
-
Functional abnormalities
- Idiopathic
- Neuro disorder; MG, peripheral neuropathy, brainstem lesion
- Crichopharyngeal achalasia or asychrony
Aside from surgeyr, name a reported method for retrieval of penetrating stick FBs
Rigid endoscopy
List 5 non-neoplastic causes of enlarged tonsils
- Primary tonsillitis
- Chronic antigenic stimulation
- BOAS
- Cleft palate
- Periodontaldisease
And for mass lesion
- Lymphangiomatous polyp
- Cyst
What is % metastasis in tonisllar SCC
73%
Name a proposed risk factor for tonsiallr SCC development
Living in area of higher atmospheric pollution
Aside from SCC, what other tonsillar neoplasias have been reported
Lymphoma
Melanoma
Adenocarcinoma
What is MST in dogs with tonsillar SCC undergoing:
Tonsillectomy alone
Chemo +- surgery
Chemo + and radiation +- surgery
- Tonsillectomy alone: 2-5 months
- Chemo +- surgery: 7 months
- Chemo + and radiation +- surgery: 12 months
Name an approach for exploration of pterygoid muscle
Paramedian submandibular approach (Gettinger, JAAHA, 2017)
I.e. ventral approach medial to mandible, digastricula laterally, cut myelohyoid, avoid penetration of oral mucosa and reach pterygoid
What is normal intramuscular compartmental pressure in dogs?
When is fasciotomy recommended?
Normal -4 - 0 mmHg
Fasciotomy if within 30 mmHg of diastolic BP
