Pathology

Question 1

SCC

Answer 1

• twice more in men
• 90% 5 year survival for lip cancer (half for tongue)
• 50% 5 year survival for oral and pharyngeal cancer
• Erythroplakia is more malignant

Question 2

Granuloma vs Cyst

Answer 2

Granuloma (Not vital)

• defined growth that is continuous with PDL due to pulp necrosis (toxins diffuse into PA area)
• This can progress to an acute abscess, phoenix abscess (recrudescent abscess)

Cyst

• Inflammatory response of the PA area from a pre-existing granuloma
• fluid filled, epi lined
• chronic infection

Both are usually asymptomatic, radiolucent with defined borders.

Question 3

Types of Cysts

Answer 3

VITAL teeth

1. cementoma (PA cemental dysplasia) = anterior mandible = radiolucent that calcifies
2. traumatic bone cyst = not a true cyst = scallops roots
3. globulomaxillary cyst (developmental cyst) = junction of globular and maxillary process, btwn LI and canine roots.
4. Lateral Periodontal Cyst = from cystic degeneration of clear cells on dental lamina

NON-vital teeth

1. Apical scar = results from granuloma, cyst or abscess healing = well-circumscribed like their predecessor
2. Radicular cyst = occurs in a pre-existing granuloma

Question 4

Ameloblastoma and Cementoblastoma

Answer 4

Ameloblastoma = benign = locally agressive (root resorption) = multilocular radiolucencies = mand. prevalence

Cementoblastoma = cementoblast proliferation making large cementum-like tissue on roots

Question 5

PA infection bacteria

Answer 5

Strep may initiate infection, but PA pathology is due to anaerobic bugs (Porphyromonas, Bacteroides, Eubacterium, Prevotella, Fusobacterium)

Question 6

All cells in immune system originate where?

Answer 6

BW as hematopoietic stem cells which give rise to:
1. Myeloids (monocytes, MO, granulocytes, histiocytes, PMNs) = Innate = non-pecific

2. Lymphoid (Lymphocytes: T, B cells, NK cells, plasma cells) = Adaptive = specific

Mast cells = lysosomes = histamine + heparin = anaphylaxis
Histiocytes = dermal MO = acute inflam. = Langerhans in subdermal squamous epithelium
PMN, MO (monocytes once they leave the blood) = phagocyte
T cells = antigens are presented to T cells via macrophages.
B cells = bacteria, fungus, virions
NK cells = tumors and viruses

Question 7

3 stages of inflammation AND 2 phases of acute inflammation

Answer 7

1. immediate
2. acute (PMN)
3. chronic (lymphocytes, MO)

Every stage is controlled by WBCs

Phase 1 of acute inflam:

1. Vasoconstriction
2. compliment activation (c3a and c5a cause chemotaxis, where c3b cause opsonization
3. Tissue injury releases bradykinin –> prostaglandins and leukotrienes
4. Vasodilation from histamine (skin redness)

Phase 2

1. Adhesion of WBCs and margination (accumulation to a certain spot)
2. WBC diapedesis (squeeze through endothelial cells)
3. Chemotaxis
4. Phagocytosis

First to arrive are PMNs, then MO. With parasites its eosinophils. With viruses its lymphocytes.

Question 8

Treatment of gingivitis via two ways:

Answer 8

OTC essential oil rinse (Listerine)

Rx 0.12% Chlorohexidine Gluconate (12% EtOH)

Question 9

Dentigerous cyst

Answer 9

Due to degenerative changes in reduced enamel epithelium

Any tooth is associated with it

Unerupting tooth = dentigerous = primordial cyst
- TX: derive and keep it exposed

When its erupting, its called erupting cyst

Question 10

osteomyelitis

Answer 10

starts in the medullary space of trabecular bone

Suppurative (acute, infantile) vs non-suppurative (chronic, sclerosing, Garre, actincomytic) groups

Question 11

Cavernous sinus thrombosis via:

Answer 11

(1) anteriorly through the angular and inferior ophthalmic veins (canine space/deep temporal space infections via ophthalmic veins) and
(2) posteriorly through the transverse facial vein and pterygoid plexus of veins

CN 3,4,5,6 pass through the cavernous sinus

Question 12

malignant lesions

Answer 12

• Bleeds easy
• Paresthesia (painless)
• metastatic = malignant = cancer
• immobile/fixed to tissue
• anaplastic
• Hyperchromatic (Nu)
• pleomorphic
• ulcerated
• erythroplasia
• duration (meaning time)
• induration (surroudning tissue is firm to touch)

Question 13

pin point dots of blood on skin

Answer 13

Petechiae

Question 14

Bone vs Cartilage growth

Answer 14

Cartilage Growth:

1. appositional = recruits chondroblasts to add new surface matrix
2. interstitial = no recruitment needed, chondrocytes already present = mandibular condyle

Bone:
Only appositional growth. Its rigid structure inhibits interstitial growth

NOTE: cartilage is the primary determinant of skeletal growth, where bone follows passively.

Question 15

Ectopic teeth

Answer 15

Max 1M > Mand. Incisors > Mand. 1M
Max > Mand.
Class II patient’s

Question 16

Bone Formation (Not Growth)

Answer 16

messenchyme –> fibrous membrane OR cartilage

1. Intramembranous ossification = occurs in membranes of CT = osteoproginator cells –> osteoblasts –> collagen matrix forms around it to ossify = maxilla, mandible, cranial vault
2. Endochondral ossification = occurs in hyaline cartilage = cartilage cells replaced by bone (osteocytes replace chondrocytes) = short and long bones, cranial BASE (sphenoid, ethmoid, occipital bones)

Cranial vault grows in response to the brain (max in 5 yrs)
Cranial base grows are independent of growth potential
Deposition and reposition may not occur in equal amounts
Remodeling = osteons = endosteal and periosteal surfaces

Question 17

Hutchinson and mulberry teeth

Answer 17

4-6 weeks in utero prior to calcification.

Maxillary incisors and molars are only affected bc they are the only teeth forking during this time