NBDHE Test Periodontal Assessment and Treatment 1 — Questions and Answers
Question 1: In Glickman's classification of furcation involvement, a Class II furcation is best described as a defect in which:
- The probe detects a slight horizontal component but cannot enter the furcation
- The probe enters the furcation but does not pass through to the opposite side (Correct answer)
- The probe passes completely through the furcation from buccal to lingual
- The furcation involvement is visible clinically without instrumentation
Correct answer: The probe enters the furcation but does not pass through to the opposite side
Class II furcation involvement means the horizontal probe penetrates into the furcation but is blocked before exiting the other side. Class I is a slight entry only; Class III is through-and-through; Class IV is through-and-through with visible recession.
Question 2: During a periodontal reassessment, the absence of bleeding on probing (BOP) is clinically most valuable as:
- A positive predictor of current active bone loss
- A reliable negative predictor of continued attachment loss (Correct answer)
- Confirmation that the patient has achieved optimal plaque control
- An indicator that periodontal maintenance can be discontinued
Correct answer: A reliable negative predictor of continued attachment loss
Research consistently shows that absence of BOP is a strong negative predictive value (approximately 98%) for periodontal stability — sites that do not bleed are very unlikely to be losing attachment. It does not, however, confirm perfect oral hygiene or allow discontinuation of maintenance.
Question 3: The primary clinical feature that definitively distinguishes periodontitis from plaque-induced gingivitis is:
- Presence of bleeding on probing
- Clinical attachment loss (CAL) (Correct answer)
- Increased probing depths greater than 3 mm
- Radiographic evidence of calculus deposits
Correct answer: Clinical attachment loss (CAL)
Gingivitis involves gingival inflammation without attachment loss — the junctional epithelium remains at the CEJ. Periodontitis is defined by irreversible loss of clinical attachment and supporting alveolar bone. BOP and increased probing depths can occur in both conditions.
Question 4: On a full-mouth series of radiographs, the most common pattern of alveolar bone loss associated with generalized chronic periodontitis is:
- Angular (vertical) bone loss
- Horizontal bone loss parallel to the CEJ (Correct answer)
- Hemiseptal defects with three-wall components
- Fenestration defects at the buccal plate
Correct answer: Horizontal bone loss parallel to the CEJ
Horizontal bone loss, in which the alveolar crest is reduced in height but remains roughly parallel to a line connecting adjacent CEJs, is the most prevalent radiographic pattern in generalized chronic periodontitis. Vertical/angular defects are less common and often associated with localized aggressive disease or specific risk factors.
Question 5: According to the 2017 World Workshop classification, periodontitis Grade C (rapid rate of progression) is supported by which indirect evidence finding?
- Bone loss of less than 25% relative to root length
- Radiographic bone loss percentage to patient age ratio greater than 1.0
- Heavy supra-gingival calculus deposits with minimal attachment loss (Correct answer)
- Absence of systemic modifying factors such as diabetes or smoking
Correct answer: Heavy supra-gingival calculus deposits with minimal attachment loss
Indirect evidence for Grade C includes a bone loss %/age ratio > 1.0, which suggests bone is being lost faster than expected for the patient's age. Direct evidence includes ≥ 2 mm of bone loss within 5 years. Heavy deposits with low destruction suggest Grade A (slow progression).
Question 6: For a patient who has completed active periodontal therapy and has a confirmed history of Stage II generalized periodontitis, what is the standard recommended interval for periodontal maintenance appointments?
- Every 6 months, consistent with a routine recall schedule
- Every 3–4 months throughout the patient's lifetime (Correct answer)
- Every 12 months once clinical stability is achieved
- Every 2 months for the first year, then annually thereafter
Correct answer: Every 3–4 months throughout the patient's lifetime
Evidence-based guidelines recommend periodontal maintenance every 3–4 months for patients with a history of periodontitis, as the subgingival microbiome can re-establish pathogenic levels within approximately 9–11 weeks after professional debridement. Annual or 6-month intervals are insufficient to maintain stability in this population.
NBDHE Test Periodontal Assessment and Treatment 1
In Glickman's classification of furcation involvement, a Class II furcation is best described as a defect in which: