Dentistry — Oral Health and Dentistry, NMC MBBS licence examination syllabus (Nepal Medical Council).
Oral Health for the Medical Doctor
A patient with toothache is usually not an emergency. Occasionally they are about to lose their airway.
You are not going to fill a cavity. But dental problems arrive in medical clinics and emergency departments constantly — often because dental care is unaffordable or unavailable — and three of them matter enormously to a doctor.
The infection that stops being dental. The ulcer that is a cancer. And the mouth as a place where systemic disease announces itself before anything else does.
The dental infection that becomes an airway emergency
Most dental pain is exactly what it appears to be: a localised problem needing dental treatment, analgesia, and sometimes drainage. It is not a medical admission.
The exception is what you must be able to recognise. Infection from a lower tooth can spread into the tissue spaces of the floor of the mouth and the neck. As those spaces swell, the tongue is pushed upwards and backwards — and the airway narrows from a direction that is difficult to see and difficult to instrument.
The features that change this from a dental complaint to an emergency: swelling under the jaw or in the neck, a tongue that appears raised, drooling or inability to swallow saliva, trismus, a muffled voice, and any difficulty breathing. These are the same airway red flags met in the sore throat section — because they are describing the same problem from a different starting point.
Do not wait for stridor. Stridor means the airway is already substantially narrowed, and in this situation deterioration can be rapid. Senior and anaesthetic help is called early, while the airway can still be managed in a controlled way.
The mouth as a window onto systemic disease
Looking in the mouth costs nothing and is routinely skipped. Several findings should prompt a search for something else.
Oral candida in an adult is the most useful. In a healthy adult it is uncommon, so it asks a question: is there diabetes, HIV, malignancy, immunosuppression, recent broad-spectrum antibiotics, or inhaled steroid use without rinsing? Candida in a baby is ordinary; candida in a previously well adult is a finding.
Bleeding gums are usually gingivitis from plaque. But consider vitamin C deficiency, a clotting disorder, and leukaemia — gum infiltration and bleeding can be a presenting feature.
A sore, smooth, depapillated tongue points to iron, B12 or folate deficiency. It is worth recognising because it may be the visible sign that leads you to the anaemia.
A dry mouth is very often iatrogenic — a great many drugs cause it — but also occurs with dehydration, poorly controlled diabetes and autoimmune disease. A dry mouth is not trivial: saliva protects teeth, so a persistently dry mouth causes rapid dental decay.
The ulcer that must not be dismissed
Most mouth ulcers are benign and heal within a couple of weeks. The rule that matters is about the ones that do not.
Any oral ulcer persisting beyond a few weeks requires assessment, and the trap is that early oral cancer is frequently painless. A patient will not necessarily complain about it, and a painless ulcer feels reassuring when it should not.
Ask about the risk factors rather than assuming them:
Tobacco in any form — smoked, or chewed and held in the mouth.
Betel quid and areca nut, with or without tobacco. This matters particularly in South Asia and is often not volunteered, because it is not thought of as a drug.
Alcohol, and the risk from combining alcohol with tobacco is greater than either alone.
White or red patches that do not rub off are premalignant lesions rather than infections — the fact that they cannot be wiped away distinguishes them from candida. Red patches carry the higher risk of malignant change. Both need referral, not reassurance.
💡 The reason this is worth a doctor's attention: oral cancer is visible. Unlike almost every other malignancy, it sits in a place you can see with a torch, and it is curable when small. It is nonetheless commonly diagnosed late — because nobody looked. Examining the mouth of a patient with tobacco or betel habits takes under a minute.
A knocked-out tooth
This arrives in emergency departments and there is a genuinely time-critical correct answer, which most doctors do not know.
For an avulsed permanent tooth:
Hold it by the crown, never the root. Delicate cells on the root surface are what allow the tooth to reattach, and handling or scrubbing destroys them. If it is dirty, rinse gently — do not scrub.
Replant it immediately if you can, into the correct socket and the right way round, and have the patient bite gently on a cloth to hold it.
If replanting is not possible, transport it in milk or in the patient's own saliva. Not in water, and not dry — water damages the cells and drying kills them.
Get to a dentist urgently. The chance of the tooth surviving falls with every minute out of the socket.
Two important exceptions. Do not replant a baby tooth — pushing it back risks damaging the developing permanent tooth in the bone above it. And always account for a missing tooth: if it cannot be found, it may have been swallowed or inhaled, which needs a chest X-ray rather than a shrug.
Prevention, and why it belongs in a medical consultation
Dental caries is an infectious disease driven by diet. Bacteria in plaque metabolise sugar to acid, and the acid dissolves enamel.
The counter-intuitive point that makes advice useful: it is the frequency of sugar exposure, not the total quantity, that matters most. Each exposure starts an acid attack, and the mouth needs time to neutralise it. So sipping a sweet drink slowly over an afternoon does far more damage than drinking the same amount in one go with a meal.
That single fact makes dietary advice concrete: reduce the number of times sugar enters the mouth.
Never put a baby to bed with a sweetened bottle. Saliva flow falls during sleep, so sugar sits against the teeth for hours with nothing to wash it away. This causes severe early childhood caries and is entirely preventable by advice — advice a doctor is often better placed to give than a dentist, because the doctor sees the child first.
Fluoride reduces caries, but concentrations and schedules are set by national policy and vary with the local water supply, so none is quoted here.
Putting it together
Swelling under the jaw, a raised tongue, drooling or trismus turns a toothache into an airway emergency — call for help before stridor appears.
Oral candida in a previously well adult asks a question about diabetes, HIV or immunosuppression.
An ulcer lasting beyond a few weeks needs assessment, and early oral cancer is often painless.
Ask about tobacco, betel quid and alcohol — betel is frequently not volunteered.
Avulsed permanent tooth: hold the crown, replant or transport in milk, go fast — and never replant a baby tooth.
Frequency of sugar beats quantity, and no sweetened bottle at bedtime.
No antibiotic regimens, fluoride concentrations or analgesic doses appear here: dental prescribing and fluoride policy differ between countries and with the local water supply. Use your national guideline.
Syllabus points
When toothache becomes an airway emergency
Do not wait for stridor
Oral candida in an adult asks a question
Bleeding gums, smooth tongue, dry mouth
The ulcer lasting weeks; painless is not harmless
Tobacco, betel quid and alcohol; white and red patches
Avulsed tooth — crown, milk, speed; never a baby tooth
Frequency of sugar beats quantity; the bedtime bottle
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