Periodontics and Gum Health Flashcards

Which growth factor, released from platelet-rich plasma (PRP), is MOST important for stimulating periodontal ligament cell proliferation?

Answer: Platelet-derived growth factor (PDGF)

PDGF is the primary mitogen released from platelets that stimulates PDL fibroblast proliferation and wound healing in periodontal regeneration.

The 'critical probing depth' concept in periodontal maintenance suggests that sites with probing depths below this threshold will GAIN attachment after SRP, while deeper sites will lose attachment. This threshold is approximately:

Answer: 2–3 mm

Research by Lindhe and others identified approximately 2–3 mm as the critical depth where shallow sites tend to lose and deeper sites tend to gain attachment after SRP.

Emdogain (enamel matrix derivative) promotes periodontal regeneration primarily by:

Answer: Mimicking Hertwig's epithelial root sheath proteins to stimulate cementogenesis and new attachment

Emdogain's amelogenin proteins recapitulate root development signals, inducing new cementum, periodontal ligament, and alveolar bone formation.

A patient undergoing periodontal maintenance should ideally be recalled at what interval to prevent disease recurrence in susceptible individuals?

Answer: Every 3 months

Evidence supports a 3-month recall interval for periodontal maintenance patients, as subgingival pathogen repopulation peaks by approximately 9–11 weeks post-debridement.

Which type of bone graft material carries the HIGHEST risk of disease transmission but also has the highest osteogenic potential?

Answer: Autograft

Autografts contain living osteogenic cells making them the gold standard for osteogenic potential, but autologous harvesting carries surgical morbidity rather than disease transmission risk; however, among graft types, they uniquely provide live cells.

In the Periodontal Risk Assessment (PRA) model, which factor is NOT used to calculate a patient's risk category?

Answer: Patient's income level

The Lang and Tonetti PRA model uses BOP%, residual pockets, tooth loss, bone loss/age ratio, systemic conditions, and smoking — not socioeconomic status.

Which suture technique is preferred for closing papillae after interproximal bone grafting to maximize primary closure?

Answer: Vertical mattress suture

Vertical mattress sutures evert wound edges and provide tension-free primary closure of papillae over graft material, reducing membrane/graft exposure.