Histopathology and Pathogenesis

Question 1

What is pristine gingiva?

Answer 1

• intact layer of epithelium lining the gingival crevice
• no inflammatory cells in the connective tissue
• continuous sparse migration of neutrophil leucocytes into the coronal part of the junctional epithelium and gingival crevice

Question 2

What is normal healthy gingiva?

Answer 2

• a small number of inflammatory cells in the junctional epithelium and connective tissue
• gingivitis is not clinically detectable, but inflammatory changes can be detected microscopically

Question 3

What is early gingivitis?

Answer 3

• seen after 10-20 days of plaque accumulation
• increased number of inflammatory cells in the tissue
• increased number of neutrophils emigrating into the gingival crevice
• junctional epithelium becomes thicker
• gingival connective tissue becomes more heavily infiltrated with inflammatory cells and dilated blood vessels

Question 4

What is established gingivitis?

Answer 4

• more dense infiltration of inflammatory cells in the connective tissue
• plasma cells much more evident
• collagen loss increases due to an outpouring of collagenase enzyme
• epithelium lining the gingival crevice continues to increase in thickness

Question 5

What is periodontitis histopathologically?

Answer 5

• apical migration of junctional epithelium
• first stage of attachment loss
• dense infiltrate of inflammatory cells can be seen with plasma cells now dominant
• bone loss begins to occur

Question 6

What are predisposing factors to necrotising disease?

Answer 6

• poor OH
• cigarette smoking
• raised stress levels
• malnutrition
• fatigue
• immune dysfunction or suppression
• pre-existing gingivitis
• systemic conditions e.g. leukaemia or HIV

Question 7

What are the clinical features of necrotising gingivitis?

Answer 7

• visible change in gingival contour
• loss of knife edge margin
• bleeding
• pain
• loss of apex of papilla giving punched out appearance
• a grey pseudomembranous slough
• unpleasant odour (foetor oris)
• swollen lymph nodes
• pyrexia (fever)
  May form a sequestrum

Question 8

What is a sequestrum?

Answer 8

Fragment of dead bone, caused by destruction/necrosis of periodontal ligament and bone, rapid and may lead to interproximal or facial bone

Question 9

How is necrotising diseases treated?

Answer 9

• OHI
• smoking cessation
• debridement, easiest to use an ultrasonic
• hydrogen peroxide: mouth rinse or applied directly to ulcerated tissue, beneficial due to mechanical cleansing properties, ability to release oxygen into the area, damaging the anaerobic infecting organisms
• chlorhexidine mouthwash: reduces plaque growth, patient may not be able to brush effectively due to pain but cannot penetrate pseudomembranous slough
• systemic antibiotics if pt is generally unwell: metronidazole 400mg 3X daily for 3-7 days, penicillin and tetracyclines also effective

Question 10

What is acute herpetic gingivostomatitis?

Answer 10

• presents with pyrexia, lymph gland involvement, flu-like symptoms, stomatitis, oral ulceration especially on keratinised tissue, gingivitis and pain
• caused by herpes simplex virus
• highly contagious, spread by oral lesions
• Tx: maintaining adequate fluid intake, antipyretics, topical antiseptics
• antiviral drugs such as aciclovir are not normally prescribed unless immunocompromised

Question 11

What are the different abscesses of the periodontium?

Answer 11

• gingival abscess: caused by trauma form a foreign body
• periodontal abscess: arising from an established periodontal pocket
• pericoronal abscess: flap of gum overlying partially erupted 3rd molar

Question 12

Name some bacterial complexes present in dental plaque, likely to cause periodontal disease:

Answer 12

• Porphyromonas gingivalis
• tannerella forsythus
• treponema denticola
• prevotella intermedia
• fusobacterium nucleatum