AGD Periodontics and Gum Disease 4 — Questions and Answers
Question 1: According to the 2017 World Workshop classification, Stage III periodontitis is distinguished from Stage II by:
- The presence of bleeding on probing
- Tooth loss due to periodontitis or complexity factors like vertical bone loss ≥33% (Correct answer)
- Probing depths exceeding 4 mm
- The presence of furcation Class I involvement
Correct answer: Tooth loss due to periodontitis or complexity factors like vertical bone loss ≥33%
Stage III introduces complexity factors such as vertical bone loss ≥33%, furcation Class II or III, or tooth loss attributable to periodontitis, distinguishing it from Stage II.
Question 2: Chlorhexidine gluconate reduces supragingival plaque primarily through which mechanism?
- Inhibiting bacterial DNA replication
- Disrupting bacterial cell membranes by binding to negatively charged sites (Correct answer)
- Chelating calcium ions required for plaque calcification
- Reducing salivary pH to inhibit bacterial growth
Correct answer: Disrupting bacterial cell membranes by binding to negatively charged sites
Chlorhexidine is a cationic bis-biguanide that binds to negatively charged bacterial cell membranes, causing cytoplasmic leakage and cell death.
Question 3: A connective tissue graft placed under a coronally advanced flap is the gold standard for treating which type of gingival recession?
- Miller Class III recession
- Miller Class I and Class II recession (Correct answer)
- Miller Class IV recession
- Recession associated with active periodontitis
Correct answer: Miller Class I and Class II recession
Miller Class I and II recessions have intact interdental bone and tissue, allowing predictable complete root coverage with a subepithelial connective tissue graft under a coronally advanced flap.
Question 4: Enamel matrix derivative (Emdogain) is derived from which biological source and promotes periodontal regeneration by:
- Bovine bone; stimulating osteoblast differentiation
- Porcine enamel; mimicking cementogenesis and PDL fiber formation (Correct answer)
- Human amnion; providing growth factor scaffolding
- Coral; offering a calcium phosphate lattice
Correct answer: Porcine enamel; mimicking cementogenesis and PDL fiber formation
Emdogain contains amelogenin proteins derived from developing porcine teeth that mimic the developmental process of cementum and PDL formation to promote periodontal regeneration.
Question 5: Which systemic condition most directly impairs neutrophil chemotaxis and is strongly associated with early-onset severe periodontitis in children?
- Type 2 diabetes mellitus
- Papillon-Lefèvre syndrome (Correct answer)
- Cyclic neutropenia
- Down syndrome
Correct answer: Papillon-Lefèvre syndrome
Papillon-Lefèvre syndrome involves mutations in cathepsin C causing severe neutrophil dysfunction and results in aggressive periodontal destruction and premature tooth loss in children.
Question 6: The critical probing depth at which surgical treatment tends to result in better attachment level gains than non-surgical treatment is generally:
- 2–3 mm
- 4–5 mm
- Greater than 5–6 mm (Correct answer)
- Greater than 8 mm
Correct answer: Greater than 5–6 mm
Evidence suggests that surgical therapy produces greater attachment level gains than non-surgical treatment at initial probing depths greater than 5–6 mm.
Question 7: Which term describes the distance from the free gingival margin to the mucogingival junction?
- Biologic width
- Keratinized tissue width (Correct answer)
- Clinical attachment level
- Probing depth
Correct answer: Keratinized tissue width
The width of keratinized tissue is measured from the free gingival margin to the mucogingival junction, encompassing both free and attached gingiva.
AGD Periodontics and Gum Disease 4
According to the 2017 World Workshop classification, Stage III periodontitis is distinguished from Stage II by: