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-1β and TNF-α are the dominant pro-inflammatory cytokines that upregulate RANKL expression and directly stimulate osteoclastogenesis, driving alveolar bone loss in periodontitis.

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

Per Page and Schroeder's staging, the initial/early lesions are dominated by neutrophils and T lymphocytes, while the established/advanced lesion is characterized by B cells and plasma cells as the primary infiltrate.

Question 3

RANKL contributes to alveolar bone destruction in periodontitis primarily by:

Accepted Answer

Activating osteoclast precursor differentiation and osteoclast resorptive activity

Answer

RANKL binds to RANK on osteoclast precursors, triggering their differentiation into mature osteoclasts and activating their bone-resorbing capacity, a process blocked by the decoy receptor osteoprotegerin (OPG).

Question 4

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

Accepted Answer

Increased, tipping the balance toward net bone resorption

Answer

Periodontitis sites show elevated RANKL and suppressed OPG production from PDL fibroblasts and osteoblasts, resulting in a high RANKL:OPG ratio that favors osteoclastogenesis and bone loss.

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

MMPs, particularly MMP-1, -2, -8, and -13, cleave fibrillar collagens and other ECM proteins in the periodontal ligament and connective tissue, irreversibly destroying the structural attachment apparatus.

(ABP) American Board of Periodontology Practice Test

(ABP) American Board of Periodontology Practice Test

ABP Periodontal Pathogenesis and Host Response 2