NBDHE NBDHE Periodontal Assessment and Treatment 4 — Questions and Answers
Question 1: Which of the following best describes 'junctional epithelium'?
- Epithelium lining the outer surface of the gingiva
- Non-keratinized epithelium that attaches the gingiva to the tooth surface (Correct answer)
- Epithelium covering the alveolar mucosa
- Keratinized epithelium that forms the oral sulcular epithelium
Correct answer: Non-keratinized epithelium that attaches the gingiva to the tooth surface
Junctional epithelium is a non-keratinized epithelium that forms the epithelial attachment at the base of the gingival sulcus, attaching to the tooth via hemidesmosomes.
Question 2: During a periodontal examination, a patient shows 4 mm probing depths with no bone loss radiographically and bleeding on probing. This finding is consistent with:
- Healthy periodontium
- Gingivitis on a reduced periodontium
- Initial periodontitis (Stage I)
- Plaque-induced gingivitis on an intact periodontium (Correct answer)
Correct answer: Plaque-induced gingivitis on an intact periodontium
Probing depths of up to 4 mm with bleeding on probing but no radiographic bone loss or CAL indicates plaque-induced gingivitis, which is reversible with proper plaque control.
Question 3: The principle behind guided tissue regeneration (GTR) is to:
- Eliminate pocket depth by resecting bone to a more apical level
- Use a membrane to exclude epithelium and allow periodontal ligament cells to repopulate the defect (Correct answer)
- Graft bone from a donor site to fill the defect
- Apply growth factors to stimulate cementum formation only
Correct answer: Use a membrane to exclude epithelium and allow periodontal ligament cells to repopulate the defect
GTR uses barrier membranes to exclude fast-growing epithelium and connective tissue, allowing slower-growing periodontal ligament and bone cells to repopulate the defect for true regeneration.
Question 4: Which oral hygiene aid is most recommended for cleaning under a fixed partial denture (bridge) pontic area?
- Standard dental floss
- Superfloss or floss threader (Correct answer)
- Interdental brush only
- Water flosser exclusively
Correct answer: Superfloss or floss threader
Superfloss or a floss threader allows patients to thread floss under the pontic of a fixed bridge to clean the gingival surface of the pontic and adjacent abutment margins.
Question 5: What is 'biologic width' and why is it clinically significant in restorative dentistry?
- The distance between the contact point and the alveolar crest, important for papilla preservation
- The combined dimension of junctional epithelium and connective tissue attachment, which must not be violated by restorative margins (Correct answer)
- The minimum amount of keratinized gingiva needed for implant stability
- The distance from the CEJ to the mucogingival junction
Correct answer: The combined dimension of junctional epithelium and connective tissue attachment, which must not be violated by restorative margins
Biologic width (~2 mm) is the combined height of junctional epithelium (~1 mm) and supracrestal connective tissue (~1 mm); placing restorative margins within it causes chronic inflammation and bone loss.
Question 6: A patient presents with gingival enlargement associated with phenytoin (Dilantin) use. What is the most appropriate initial dental management?
- Gingivectomy as the first treatment
- Prescribe systemic antibiotics
- Optimize oral hygiene and perform thorough scaling and root planing (Correct answer)
- Refer immediately for medication change without providing dental treatment
Correct answer: Optimize oral hygiene and perform thorough scaling and root planing
Drug-influenced gingival enlargement is exacerbated by plaque; improving oral hygiene and performing SRP often reduces enlargement significantly before considering surgery.
Question 7: Which component of the periodontal ligament (PDL) inserts into cementum on the tooth side and alveolar bone on the other?
- Resting cells
- Sharpey's fibers (Correct answer)
- Oxytalan fibers
- Intermediate plexus cells
Correct answer: Sharpey's fibers
Sharpey's fibers are the embedded portions of principal PDL fiber bundles that insert into both cementum and alveolar bone, anchoring the tooth in the socket.
NBDHE NBDHE Periodontal Assessment and Treatment 4
Which of the following best describes 'junctional epithelium'?