Benign lesions and cysts Flashcards
(37 cards)
When performing a biopsy what measurements are ideal
Min 3mm
Ideal 4-6mm with 2mm deep due to shrinkage
What is tumor stagings
T= tumor
T0- none, T1- <20mm, T2- 20-40mm, T3 >40mm
N= LN
N0 - none, N1- movable ipsilateral, N2- Movable contralat or bilat, N3- Fixed
M= Distant Met
M0- none, M1- Positive
Odontogenic tumors originate from
Rests of Malassez within the PDL (centrally)
Rests of Serres within the gingiva (peripherally)
What are epithelial tumors
ameloblastoma
Convential Ameloblastoma
CAA
Amyloid Producing Tumor
Convential ameloblastoma
Maxilla
Canine and premolar
Interosseous and cystic 95%
Lysis
Mixed lytic/proliferative
Doesnt infiltrate surrounding bone
Common findings for both CAA and conventional ameloblastoma
Bone lysis
Tooth involvement / Tooth displacement
Cortical bone involvement
Contrast enhancement on CT
Recurrence not observed even with narrow surgical margins or treatment by cyst enucleation
Study suggests that aggressive wide surgical excision margins (> 1cm) may not be necessary
No evidence of metastasis found in any cases → supports understanding of ameloblastomas as benign tumors
CAA
Most common OT in dogs – 45%
Not metastatic
Infiltration of the surrounds bone
Intraosseous is more aggressive
Rostral mandible (51%)
Golden ret, akita, cocker
Tooth displacement
Amyloid producing tumors
Rare
Derived from ameloblasts
slow growing no mets
Middle age dogs
Mesenchymal Tumors (3)
POF
myxoma/myxofibroma
POF
Second most common tumor
Slow growing
2 variants- fibromatous and ossifying
What is the difference between myxoma and myxofibroma
Odontogenic myxomas- mesenchymal tumors that arise from developing dental papilla
Odontogenic myxofibroma- when mesenchymal tumors that arise from developing dental papilla and found in conjunction with a large amount of collagen
Both highly infiltrative
Mixed mesenchymal/epithelial tumor
Odotoma
Feline inductive odontogenic tumor
Odontoma
Benign, inductive
Seen in young dogs, cats
6-18 months
Associated with unerupted tooth, alveolar swelling
Two types
1. Compound odontoma contains tooth-like structures, denticles, orderly pattern of dental tissue
2. Complex odontoma – disorderly dental tissue
FIOT
Young cats (8-18 mo)
termed inductive since odontogenic epithelium induces mesenchymal cells to form aggregated foci of dental pulp-like cells
Raised, submucosal, rapidly expansive, locally destructive, soft tissue mass
Usually unilateral on rostral MX
proliferation of the attached gingiva, often secondary to chronic inflammatory response to plaque, food impaction, dental malposition, dental resorption
Gingival hyperplasia
Breeds: Boxer, collie, Great dane, dalmation, dobie
Drugs that induce GH
- Phenytoin derivatives
Chronic, slow growing
Regrows after sx resection
Usually regresses when drug discontinued - Calcium channel blockers (i.e. amlodipine, nifedipine)
Calcium plays an important role in apoptosis
Gingiva has the highest activity of transglutaminase- calcium dependent enzyme involved in apoptosis
Theorized that decreased CA reduces normal apoptosis causing deregulation of tissue overgrowth - Cyclosporine
cyclosporine developed gingival enlargement
Reversible once drug discontinued
Reactive lesion due to irritation caused by plaque/calculus
Focal fibrous hyperplasia
Rostral maxilla>other regions
Reactive lesion occurring at a specific site on gingiva, response to chronic, low-grade irritation
Pyogenic granuloma
Peripheral giant cell granuloma
Rare (cats>dog)
Response to injury - lymphocytes, plasma cell, macrophages in submucosal stroma
MX>MN
High recurrence
Types of developmental cyst
Dentigerous/follicular
Lateral
Types of inflammatory Cyst
Periodical/radicular
Most common Odontogenic cyst
Dentigerous
Tissue remnants of enamel organ and REE
Brachy overrepresented
MNM1 most affected
Periapical/Radicular cysts
Infrequent
Inflammatory from nonvital teeth
Lateral Cysts
Developmental
ON VITAL TEETH
noninflammatory, nonkeratinized, developmental odontogenic cysts. The LPC occurs lateral to the root of vital teeth, most commonly the mandibular premolars in humans
