His Face Dropped in the Chair and It Was Not the Injection

Quick answer: A facial droop during a dental appointment can be a local anaesthetic effect, Bell's palsy, or a stroke, and the three are distinguished within a minute. If the forehead still wrinkles and the arm or speech is affected, treat it as a stroke and call emergency services immediately. Time is the only variable anyone in the room controls.

The call

He was in the chair for two fillings on the lower left. The anaesthetic had been given twenty minutes earlier and was working normally.

Reuven, 71, from Beit Shemesh, a regular patient with high blood pressure and atrial fibrillation, had been talking about his grandchildren between instruments.

Then his speech changed mid-sentence. Slurred, effortful, and he seemed to know it.

What we found

The right side of his face had dropped. The wrong side. The anaesthetic had been given on the left.

That single observation is what turned this from a dental appointment into a medical emergency, and it took about three seconds.

The distinctions, made immediately:

Local anaesthetic affecting the facial nerve is a recognised complication — anaesthetic solution deposited too far back can reach the parotid gland and affect the facial nerve, producing a droop and an inability to close the eye on that side. It is temporary, resolves within a few hours, and is alarming rather than dangerous. But it occurs on the side that was injected, and there are no other symptoms. His was on the opposite side.

Bell's palsy affects the whole side of the face including the forehead, comes on over hours rather than seconds, and does not affect the arm or speech.

A stroke typically spares the forehead, because of how the forehead muscles are innervated from both sides of the brain. It comes on suddenly and commonly affects the arm and speech as well.

The check, done in under a minute:

• Face — could he smile? The right side did not move. Could he wrinkle his forehead? He could, on both sides. The forehead was spared.
• Arms — could he raise both and hold them? The right arm drifted downward within seconds.
• Speech — slurred and hesitant, and he was aware of it, which was distressing for him.
• Time — onset was known precisely, because we had been talking to him. That is unusually valuable information and it was recorded.

Forehead spared, arm weak, speech affected, sudden onset, in a 71-year-old with atrial fibrillation. That is a stroke until proven otherwise.

What we did

Emergency services called immediately, before anything else and before any further assessment. The call was made by the nurse while the assessment continued, not after it.

The exact time of onset given, which is the single most important piece of information transmitted, because eligibility for clot-busting treatment depends on it. We knew it to the minute.

His medical history and medication list read out from the notes to the ambulance crew, including the atrial fibrillation and the anticoagulant he was taking. That is directly relevant to how a stroke is treated and dental records had it to hand.

The treatment abandoned. The rubber dam removed, the tooth left with a temporary dressing, and nothing else attempted. A half-finished filling is irrelevant.

He was kept sitting up, not laid flat, monitored, kept warm, and someone stayed talking to him the entire time. Nothing to eat or drink, because swallowing is often impaired and the risk of aspiration is real.

His wife was phoned from his records while we waited.

The ambulance arrived in eleven minutes and he was at hospital shortly after.

What we did not do: we did not wait to see whether it settled, we did not give aspirin, and we did not drive him ourselves. Waiting is the commonest and most costly error. Aspirin is contraindicated until a bleed has been excluded by scanning. Driving a patient bypasses the pre-alert that gets the stroke team assembled before arrival.

The outcome

He had an ischaemic stroke and received thrombolysis within the treatment window, which was possible because the onset time was known exactly and the ambulance was called within two minutes.

He spent eleven days in hospital and several months in rehabilitation. He has a residual weakness in his right hand and his speech recovered almost fully.

He came back for the two fillings four months later, and made a point of asking who had made the call.

The reason to tell this story is not that dental practices see strokes often. It is that a facial droop in a dental chair has an obvious innocent explanation available, and reaching for it is the mistake. The forehead test and the wrong-side observation are what prevented that.

What to do if this happens to you

1. Call emergency services first. Do not assess further, do not phone a relative, do not wait.
2. Note the exact time symptoms started. It determines which treatments are possible.
3. Check the forehead. If it still wrinkles, that points away from Bell's palsy and towards a stroke.
4. Check the arms and the speech, not only the face.
5. Give nothing by mouth, including aspirin.
6. Do not drive them. An ambulance alerts the hospital before it arrives.

Sudden face droop, arm weakness or slurred speech is an emergency — call emergency services immediately, not a dental practice. For dental care after a stroke, Ramat Beit Shemesh Urgent Dental Care can plan around it. 055-985-8845 · WhatsApp https://wa.me/972559858845 · Harav Kook 28/1, Beit Shemesh

This is a composite clinical story. It reflects a presentation we see regularly in Beit Shemesh and Ramat Beit Shemesh; the name and details are illustrative and are not those of a real patient.