classification and histopathololgy Flashcards
What does pulp development involve?
External enamel epithelium Stellate reticulum Ameloblasts Dental papilla Hertwigs root sheath
What does normal pulp anatomy involve?
Odontoblasts Cell-free zone Cell-rich zone (fibroblasts and nerves) Pulpal fibrous tissues (fibroblasts, blood vessels and nerves) Predentine Mineralised dentine Lymphatics Small nos of macrophages and lymphocytes Stem cells
What is secondary dentine?
Physiological
Laid down throughout life
Regular tubular structure
Pulp gets smaller
What is tertiary dentine?
Reactionary and reparative
Response to insult to pulp
Structure varies
What pulp stones are there?
True- composed of dentine
False- amorphous calcifications
They increase in no and size w age
How is pulp pathology classified?
Inflammatory- pulpitis
Degenerative- fibrosis, calcifications, internal resorption
What are dentine defence reactions to pulpitis?
Dentine sclerosis and reactionary dentine formation
How is pulpitis classified?
Acute- open(exposure tooth fracture) or closed(trauma)
Chronic- open(open caries) or closed(caries)
What are the causes of pulpitis?
Caries secondary to- fracture, lateral root canals, canals in furcation, invaginate odontome
Bacteraemia
Physical/chemical/mechanical trauma
Secondary to attrition/abrasion/erosion
What are the clinical features of pulpitis?
Poorly localised pain May radiate to face, neck, jaw Continuous or intermittent Reversible Symptomatic irreversible Asymptomatic irreversible
Why are the patterns of pulpitis?
Starts as localised lesion relating to proximity of caries
Inflammation spreads through pulp
Rate varies between teeth and individuals
What are the protective responses for pulpitis?
Tertiary dentine due to caries increases distance of pulp from irritant
(Increased blood flow and small increase in neutrophils, lymphocytes, plasma cells and macrophages)
What is the response to established dentine caries?
Acute inflammation-
- vasodilation
- inflammatory exudate
- accumulation of neutrophils
- death of odontoblasts
What is the problem with pulp?
Pulpitis is in a closed environment
~inflammatory exudate causes rapid rise in tissue pressure
~venous circulation collapses
~blood flow stops
~tissue hypoxia
~local tissue necrosis
~inflammatory mediators released
~more inflammation and neutrophil accumulation
~forms pus- pulp abscess (can be localised and surrounded by granulation tissue)
How might the inflammation spread?
Could involve whole pulp
Pus can drain into oral cavity if pulp exposure
Total necrosis may follow
What is a pulp polyp?
Chronic hyperplastic pulpitis Usually first permanent molars in kids ~open apices so good blood supply ~open caries with pulp exposure ~surface ulcerated and covered by fibrin and neutrophils ~may become covered by epithelium by either saliva or gingival crevice? ~clinically red and bleeds easily ~often painless
