Halitosis of Oral Origin

Halitosis is an unpleasant odour of the exhaled breath. In 80 to 90 percent of people with persistent halitosis the source is in the mouth, usually from bacterial putrefaction of sulphur containing proteins on the tongue and in periodontal pockets, releasing volatile sulphur compounds (hydrogen sulphide, methyl mercaptan, dimethyl sulphide).

• Physiological halitosis: morning breath (reduced saliva overnight), fasting, stress, and certain foods (garlic, onion, spices), which resolves with eating, brushing and drinking.
• Oral causes: tongue coating (the commonest, posterior dorsum), periodontal disease and pockets, necrotising gingivitis, pericoronitis, caries with food packing, poor oral hygiene, dental plaque on dentures and appliances, dry mouth, oral infections, ulcers and tumour, tonsilloliths, and smoking and betel nut use.
• Extra oral causes (about 10 percent): upper airway (sinusitis, tonsillitis, post-nasal drip, foreign body in the nose of a child), lower respiratory (bronchiectasis, lung abscess, tumour), gastrointestinal (Helicobacter pylori, reflux, Zenker diverticulum, bowel obstruction), systemic (diabetic ketoacidosis with acetone, uraemia with ammonia, liver failure with fetor hepaticus), drugs (disulfiram, dimethyl sulfoxide, nitrates), and trimethylaminuria.
• Pseudohalitosis (the patient believes in an odour that others cannot detect) and halitophobia need sensitive handling.

• Patient reports (or family notes) bad breath, bad taste, tongue coating, coating of the throat, or a dry mouth; it is often worse on waking, between meals, and with stress.
• Examination: thick white or yellow brown coating of the posterior dorsum of the tongue, gingival inflammation and bleeding, periodontal pockets, calculus, caries, defective restorations, dentures with biofilm, dry mucosa, ulcers, tonsil crypts with white concretions (tonsil stones), and nasal discharge.
• Systemic clues: fruity breath (ketones), fishy or ammonia breath (renal failure), musty breath (liver disease), faecal breath (obstruction), foul nasal discharge.
• Ask about oral hygiene, tongue cleaning, mouthwash use, tobacco, alcohol, diet (including fasting and low carbohydrate diets), medicines, reflux symptoms, nasal symptoms, and psychological distress.

• Organoleptic test: the clinician smells breath from the mouth and nose separately at about 10 cm (score 0 to 5, with 2 or more considered detectable); the patient should avoid garlic and onion for 48 hours, antibiotics and mouthwash for 1 week, and perfume and brushing on the day.
• Instruments: portable sulphide monitor (halimeter; a reading of over 110 to 150 parts per billion suggests halitosis) or gas chromatography.
• Oral examination and periodontal charting; radiographs for caries, bone loss and impacted teeth; saliva flow assessment.
• Investigations for suspected extra oral cause: blood glucose, ketones, urea and creatinine, liver function, H. pylori breath or stool test, sinus imaging, chest X-ray, nasal endoscopy, and ENT or gastroenterology review.
• Differentials: physiological halitosis, pseudohalitosis, halitophobia, delusional disorder, trimethylaminuria (fishy odour from sweat and urine too), and drug related odour.

Mechanical measures (the foundation)

• Brush teeth twice daily for 2 minutes with fluoride toothpaste 1350 to 1500 ppm, clean between teeth daily with interdental brushes or floss, and replace the brush every 3 months.
• Clean the tongue every morning and evening with a tongue scraper or soft brush from the back to the front (10 strokes), taking care not to cause gagging or injury.
• Clean dentures and appliances daily, remove at night, and soak in a denture cleanser.

Treat oral disease

• Scaling and root surface debridement for gum disease, treatment of caries and defective restorations, extraction of hopeless teeth, and treatment of pericoronitis or ulcers.
• Tonsil stones: gargle with salt water, gentle irrigation, low pressure oral irrigator; tonsillectomy only for severe recurrent cases.
• Oral candidiasis: miconazole oral gel 2.5 mL (124 mg) four times daily for 7 days after food and continued for 2 days after healing, or nystatin suspension 100 000 units/mL 1 mL four times daily for 7 days.

Chemical adjuncts

• Chlorhexidine gluconate 0.2 percent mouthwash 10 mL (or 0.12 percent 15 mL) for 1 minute twice daily for 2 weeks at most (staining, taste change).
• Longer term: cetylpyridinium chloride 0.05 to 0.07 percent, or zinc containing mouthwash (zinc chloride or zinc acetate), twice daily; they neutralise volatile sulphur compounds.
• Avoid alcohol based mouthwashes, which dry the mouth and worsen halitosis.

Dry mouth, diet and habits

• Sip water through the day, chew sugar free gum or use xylitol lozenges, avoid long fasting, limit coffee, alcohol and tobacco; stop smoking and betel nut.
• Review medicines that reduce saliva; use saliva substitutes when needed.

Extra oral causes

• Treat the identified disorder: sinusitis, reflux (omeprazole 20 mg daily for 4 to 8 weeks), H. pylori eradication (for example omeprazole 20 mg, amoxicillin 1 g and clarithromycin 500 mg, each twice daily for 14 days), diabetes control, and nasal foreign body removal in children.

Psychological support

• Reassure patients with pseudohalitosis, explain the objective findings, and offer cognitive behavioural therapy for halitophobia; avoid repeated unnecessary treatments.

Follow up

• Review at 2 to 4 weeks with repeat organoleptic scoring; refer to a dentist or periodontist for persistent oral causes and to ENT or gastroenterology for persistent breath odour with normal oral findings.