Periodontology
Periodontology tests plaque-induced periodontal disease, classification, diagnosis, and treatment. The exam expects accurate use of probing depth, clinical attachment level, staging, and grading.
Core rules
- Gingivitis is reversible inflammation limited to gingiva; periodontitis involves attachment loss and bone loss.
- Clinical attachment level equals probing depth plus recession, or probing depth minus gingival enlargement.
- Staging uses severity and complexity; grading uses progression rate and risk factors such as smoking and diabetes.
- Scaling and root planing is the initial treatment for periodontitis; antibiotics are adjuncts, not substitutes.
- Smoking and poorly controlled diabetes worsen periodontal risk.
Worked example
A tooth has probing depth 5 mm on the mesial aspect and 2 mm of recession. The clinical attachment level is 7 mm. If bone loss extends to the middle third of the root and the patient smokes, the case is not just gingivitis. The correct reasoning combines CAL, bone loss, and risk factors to assign periodontitis stage and grade, then plan nonsurgical therapy and reassessment.
Traps
- Do not equate probing depth with attachment loss when recession or enlargement is present.
- Calculus is a plaque retentive factor, not the direct cause of periodontitis.
- Antibiotics alone do not remove biofilm; mechanical debridement is essential.
- Aggressive periodontitis is not diagnosed from a single deep pocket.