ABP Periodontal Pathogenesis and Host Response 2

Question 1

Which cytokines are the principal mediators of osteoclast-driven bone resorption in periodontal disease?

Accepted Answer

IL-1β and TNF-α

Answer

IL-4 and IL-10

Answer

TGF-β and IL-13

Answer

IL-6 and IFN-γ

Question 2

As the periodontal lesion progresses from gingivitis to chronic periodontitis, the predominant infiltrating immune cell transitions through which sequence?

Accepted Answer

Neutrophils → T lymphocytes → B cells and plasma cells

Answer

Macrophages → neutrophils → plasma cells

Answer

B cells → T cells → neutrophils

Answer

Plasma cells → macrophages → neutrophils

Question 3

RANKL contributes to alveolar bone destruction in periodontitis primarily by:

Accepted Answer

Activating osteoclast precursor differentiation and osteoclast resorptive activity

Answer

Inhibiting osteoclast apoptosis through TRAP enzyme upregulation

Answer

Stimulating osteoblast differentiation from periodontal ligament cells

Answer

Sequestering osteoprotegerin to prevent it from binding to RANK

Question 4

In active periodontal disease sites, the RANKL-to-OPG ratio is:

Accepted Answer

Increased, tipping the balance toward net bone resorption

Answer

Decreased, favoring net bone formation

Answer

Unchanged compared to periodontally healthy tissue

Answer

Highly variable with no consistent directional change

Question 5

Matrix metalloproteinases (MMPs) contribute to periodontal tissue destruction primarily by:

Accepted Answer

Degrading extracellular matrix components including type I and III collagen

Answer

Stimulating fibroblast collagen synthesis and tissue repair

Answer

Directly activating the classical complement cascade

Answer

Inhibiting osteoclast recruitment to alveolar bone

Question 6

Which complement activation pathway is primarily triggered by bacterial lipopolysaccharide (LPS) present in the periodontal pocket?

Accepted Answer

Alternative pathway via spontaneous C3 hydrolysis amplified by LPS

Answer

Classical pathway initiated by C1q binding to antigen-antibody complexes

Answer

Lectin pathway activated by mannose-binding lectin (MBL)

Answer

Terminal pathway via direct activation of the membrane attack complex

Question 7

Prostaglandin E2 (PGE2) contributes to periodontal bone destruction primarily through:

Accepted Answer

Enhancement of RANKL expression and osteoclast activation

Answer

Inhibition of MMP secretion from gingival fibroblasts

Answer

Direct stimulation of osteoblast bone matrix synthesis

Answer

Blocking pro-inflammatory cytokine production via negative feedback