Pathology · patient case with 1 question
Healthy patient with bad breath
Scenario: A patient with BAD BREATH. Very little background information was given other than that she was HEALTHY. What are the contributing factors, EXCEPT?
Question 1
All of the following contribute to halitosis EXCEPT:
Show answer and explanation
Correct answer: C. A diet high in glucose
- A. The posterior tongue dorsum is the single largest source of oral malodour — around 80-90% of cases — because its papillary surface harbours anaerobic bacteria and desquamated cells.
- B. Periodontal disease produces deep anaerobic pockets, and periodontal pathogens generate hydrogen sulphide and methyl mercaptan directly.
- C. Correct — this is the EXCEPTION. Dietary SUGAR drives CARIES, not halitosis. Oral malodour comes from VOLATILE SULPHUR COMPOUNDS produced by anaerobic bacteria breaking down PROTEIN and sulphur-containing amino acids — so a high-protein diet, not a high-glucose one, is the dietary contributor.
- D. Reduced salivary flow removes the natural cleansing and buffering mechanism, allowing anaerobic proliferation. This is why 'morning breath' occurs after a night of reduced salivation.
Note: Roughly 85-90% of halitosis is INTRA-oral in origin. Extra-oral causes worth knowing: tonsilloliths, sinusitis and postnasal drip, GERD, diabetic ketoacidosis (acetone breath), hepatic failure (fetor hepaticus) and renal failure (ammoniacal breath).