All of the following are seen in patients who smoke EXCEPT:

Correct answer: B. Increased gingival crevicular fluid flow

• A. IS true. Nicotine causes vasoconstriction, so smokers show less erythema, less oedema and notably LESS BLEEDING on probing — which is exactly why their disease is so often underestimated at examination.
• B. CORRECT — this is the EXCEPTION. Smokers show REDUCED gingival crevicular fluid flow, not increased. Nicotine-mediated vasoconstriction and the suppressed vascular inflammatory response reduce fluid exudation into the sulcus. This is part of the same phenomenon that MASKS periodontal disease in smokers.
• C. IS true. Smoking is the strongest modifiable risk factor for periodontitis after plaque, with two to seven times the risk of attachment and bone loss, and a characteristic pattern of deeper anterior and palatal pockets.
• D. IS true. Smokers respond less well to both non-surgical and surgical therapy, show less pocket depth reduction and attachment gain, and have higher implant failure rates.

Note: Clinical trap: absence of bleeding on probing in a smoker does NOT mean health. Rely on probing depths, attachment levels and radiographs rather than bleeding indices.