Generalised bleeding on probing with an isolated 8 mm CAL loss on #23

Correct answer: D. Generalized gingivitis with localized gingival recession on tooth #23

• A. Necrotizing disease presents with punched-out, cratered interdental papillae, pain, a pseudomembrane and fetid halitosis.
• B. Periodontitis in the 2018 classification requires INTERDENTAL CAL at two or more non-adjacent teeth, or buccal/lingual CAL of 3 mm or more with pocketing over 3 mm at two or more teeth. Neither is met by a single labial defect with 2-3 mm pockets.
• C. Stage III would require interdental CAL of 5 mm or more with a generalised pattern and probable tooth loss — none of which is present.
• D. Correct. Probing depths of 2-3 mm everywhere means there is NO periodontitis — no pocketing, no interproximal attachment loss. Bleeding on probing at 80-90% of sites in the absence of attachment loss defines GENERALIZED GINGIVITIS (over 30% of sites). The isolated 8 mm CAL on the LABIAL of #23 is RECESSION, which is attachment loss of NON-PERIODONTITIS origin.

Note: KEY PRINCIPLE: attachment loss confined to the BUCCAL/LABIAL surface with normal interproximal attachment is RECESSION, not periodontitis. The 2018 classification is built on INTERDENTAL attachment loss.

Correct answer: B. Adult prophylaxis with oral hygiene instruction

• A. Scaling and root planing is the therapy for PERIODONTITIS with subgingival calculus and pocketing; with 2-3 mm probing depths it is not indicated.
• B. Correct. Because there is gingivitis without periodontitis, treatment is a PROPHYLAXIS — supragingival scaling and polishing — together with oral hygiene instruction, with particular attention to correcting the traumatic brushing technique that produced the recession.
• C. Open flap debridement is a surgical procedure for residual deep pockets after non-surgical therapy fails.
• D. Periodontal maintenance is the recall protocol for a patient PREVIOUSLY TREATED for periodontitis — this patient has never had periodontitis.

Correct answer: B. Mechanical abrasion from traumatic toothbrushing

• A. Occlusal trauma widens the periodontal ligament space and increases mobility; it does not by itself cause gingival recession.
• B. Correct. Isolated recession on the LABIAL surface of a prominent canine, in a mouth that is otherwise periodontally healthy with no tooth loss, is the signature of MECHANICAL ABRASION — aggressive horizontal brushing with a hard brush. The canine's prominent root position and thin overlying buccal plate make it the most commonly affected tooth.
• C. Orthodontic movement can cause recession by moving a root through the buccal plate, but the case gives no orthodontic history.
• D. Plaque-induced attachment loss produces INTERPROXIMAL bone loss and pocketing across multiple teeth, not an isolated labial defect with normal probing depths.

Note: Other contributors worth listing: thin gingival biotype, prominent roots and dehiscences, high frenal attachment, and lip or tongue piercings.