Fundamentals Flashcards
If you are taking an aspiration biopsy and aspirate blood, this could be either:
- You hit a vessel
- Haemangioma (benign)
If you perform an aspiration biopsy and are unable to get any fluid this means:
The lesion is solid so most likely a tumour.
Liquid = cyst
What are conventional pathology specimens stored in?
10% neutral buffered formalin
What are most pathology specimens stained with?
Haematoxylin and Eosin (H&E) or PAS
List 6 causes of cellular injury
- Hypoxia
- Chemical agents (CO2, drugs)
- Physical agents (trauma, irradiation, temp)
- Autoimmune reaction
- Nutritional imbalance
- Aging
What is the difference between hypertrophy and hyperplasia of cells?
Hypertrophy = increase in size
Hyperplasia = increase in number
What is cell metaplasia?
Change/replacement of cell phenotype of differentiated cells
If the adaptive capability of a cell is exceeded, what will happen?
Reversible or irreversible cell injurys.
If irreversible will result in cell necrosis or apoptosis.
What is the difference between necrosis and apoptosis
Necrosis - cell death after extenral stimuli - inflammation
Apoptosis - programme cell death. No inflammation
What is inflammation?
A protective response intended to eliminate initial cause of injury as well as necrotic cells and tissues resulting from original insult
What are the two major components of acute inflammation
- Vasodilation - increase blood flow and permeability
- Recruitment and accumulation of leukocytes esp neutraphils
What is the purpose of swelling?
Dilute toxins and provide influx of protective antibodies and proteins that limit infection spread
Pyogenic microbes are usually what type:
Staphylococcus
3 eamples of chronic inflammatory cells:
- Macrophages
- Lymphocytes
- Plasma cells
What are the two requirements in order for necrotic cells to be replaced by regeneration as opposed to scar
- Remaining cells must be capable of dividing
- Collagen Framework must be intact.
What is the difference between labile cells and stable cells?
Labile turnover continuously. So skin vs hepatocytes.
Oral epithelial cells are labile and the basement membrane provides the:
Scaffold
What is the process of healing of a tooth socket.
- Haematoma in socket
- Demolition of Haematoma by MAC and breakdown of necrotic bone by osteoclasts
- Regeneration of epithelial surface
- Clot replaced by granulation tissue (1-3 weeks)
- Production of woven bone
- Remodeling (woven bone replaced by lamellar bone)
List 5 local factors which impair wound healing
- Infection
- Impaired blood sypply (eg nicotine vasoconstriction)
- Foreign bodies
- Mechanical factors
- Size, location, type of wound
List 4 systemic factors which influence wound healing
- Diabetes
- Medications eg corticosteroids
- Nutritional deficiency
- Systemic illness
Why does pulp inflammation often end up being irreversible?
Because the increase of pressure in a confined space leads to vascular ischemia which results in further inflammation and eventual necrosis