Why is toothache worse at night?

The inside of a tooth is not solid. In the middle of the hard walls made of enamel and dentine there is a soft tissue called the pulp: blood vessels and the nerve. When this tissue becomes inflamed, it tries to swell, just as tissue does anywhere else in the body. But the pulp cannot swell, because the walls around it do not stretch. Fluid that cannot get out creates pressure in a closed chamber, and that pressure presses directly on the nerve endings. This is where the throbbing, pulse-like character of toothache comes from.

What changes when you lie down is the pressure itself. When you are upright, your head is above your heart and gravity helps the blood in your head drain back. When you lie down, that help disappears and the volume of blood in the vessels of the head and jaw increases. In a nerve that is already on the edge, this small increase tips it over the threshold. The same tooth that gave a dull ache all day starts to throb at night.

The second reason is attention. During the day your brain is constantly busy with something else; the pain signal arrives at the same strength but has to wait its turn. At night the queue empties, and in a quiet room the only signal left is the pain itself. The third is medication: the painkiller you took after dinner wears off in the middle of the night, and that is exactly when you wake up. The fourth is clenching at night; clenching puts extra load on the already inflamed tooth every night.

These explain why the pain gets worse at night, not why it is there. There are several causes, and they all come down to the same thing: inflammation that has reached the nerve. Deep decay reaching the nerve, a broken or cracked tooth, an old filling with decay underneath it, root canal treatment that needs redoing, or an abscess at the root tip. One more possibility lies outside the tooth: with sinusitis, the upper back teeth hurt when you lie down, because the pressure in the sinus cavity also rises when you lie flat.

The character of the pain gives the picture away. Pain that starts when something cold touches the tooth and ends within seconds once the trigger is gone shows that the nerve is still at the irritation stage; that tooth does not hurt on its own at night. Pain that starts on its own, lasts for minutes, gets worse with heat and becomes severe when you lie down is irreversible inflammation of the nerve (irreversible pulpitis): the nerve tissue can no longer cope with the inflammation. Sharp pain when you bite, the tooth feeling as if it has grown longer and swelling in the gum show that the inflammation has come out of the root tip and moved into the bone, in other words an abscess.

Night-time pain on its own is not a reason to go to A&E; a few signs that come with it are. Swelling in the face that is growing, a high temperature, being unable to open your mouth and difficulty swallowing show that the infection has spread into the soft tissue; this picture progresses within hours and does not wait until morning. In every other situation the plan is the same: you manage the night properly and see a dentist the next day.

The decision depends not on how severe the pain is, but on how far the inflammation has reached. The distinction becomes clear after an examination, a vitality test and an X-ray; the tooth with the most severe pain may be saveable, while a tooth that does not hurt at all may be on the verge of extraction.

What follows is not treatment. The aim is to manage the pain until morning without harming the tooth in the meantime. Follow the steps in this order.

1. 1

   Raise your head

   Sleep with two pillows or with the head of the bed raised. When your head stays above the level of your heart, less blood goes to the area and the pressure inside the tooth drops. This is the step that works fastest for night-time pain, and it costs nothing. For the same reason, do not lie on the painful side.

2. 2

   Take a painkiller just before bed

   Take paracetamol or ibuprofen at the dose given on the patient information leaflet, just before you get into bed; this way, the medicine is working during the most painful hours of the night. If you have a condition affecting your stomach or kidneys, or you take blood thinners, ask your pharmacist which one to take.

3. 3

   Use cold, not heat

   Hold ice wrapped in a thin cloth against the outside of your cheek for fifteen minutes, then take a break. A hot compress, a hot shower or a hot towel held to the face increases blood flow to the area: the swelling grows, the pressure rises and the pain gets worse. If there is an abscess, heat speeds up the spread.

4. 4

   Swallow aspirin; do not put it on the tooth

   An aspirin tablet pressed against the painful tooth or the gum does not stop the pain. The acid burns the lining of the mouth and leaves a white, painful sore; the next day the dentist has to deal with both the tooth and the burn. Painkillers only work when swallowed. Do not give aspirin to anyone under 16; in this age group, paracetamol or ibuprofen is used.

5. 5

   Clean the area and rinse with salt water

   Food debris trapped under the gum or in a cavity increases the pressure. Gently clean that area with a soft brush; do not use floss around the painful tooth, as pressing floss into inflamed gum makes the pain and swelling worse. If a piece of debris will not come out from between the teeth, do not fiddle with it yourself; show it to your dentist the next day. Then rinse with half a teaspoon of salt in a glass of warm water. Stopping brushing that area because it hurts makes things worse.

6. 6

   Book an appointment first thing in the morning

   Every night spent getting by on painkillers is time the inflammation gains to progress. Even if the pain has gone by morning, do not cancel the appointment: the pain going quiet often means the nerve has died, and an abscess builds up during that silent period.

The only thing that ends night-time pain is removing the pressure at its source. The options below are listed by where the pain is coming from, with the least invasive first.

We are not writing this to frighten you, but so that you can ask the right question whichever dentist you see. If a dentist does not explain these things without being asked, ask.

The sequence below applies to the path of root canal treatment or draining an abscess. If the tooth has been taken out, the process is shorter and the plan afterwards is longer-term.

1. The first 24 hours

   Once the inflamed tissue is removed and the pressure is relieved, the night-time pain ends; the most noticeable difference is being able to sleep on the first night. The tooth stays tender when you bite for a few days, and this passes as the tissue at the root tip settles down.

2. The first week

   If there is swelling, it goes down after the third day and you need fewer painkillers. If the pain rises again during this week, it shows the procedure has not been completed; let your dentist know without waiting.

3. Covering the top of the tooth

   A tooth whose root canal treatment has been finished is not left for months with a temporary filling. A temporary filling leaks, bacteria get back into the canal and a tooth whose crown is delayed cracks. At that point the whole treatment is wasted and the only option left is extraction.

4. If the tooth could not be saved

   The bone at the extraction site shrinks quickly in the first few months; that is why what will replace the tooth is planned before the extraction. For patients with many missing teeth, we sort out the whole mouth in a single plan: the implants lock mechanically into the hard basal and cortical layer deep in the jaw; the upper area where a conventional implant is placed, the alveolar bone that shrinks with tooth loss, is not used for support. Adding bone and months of waiting do not come into it; at the end of the three clinical days you leave with your final fixed teeth.

We do not give a single figure on this page: a tooth causing pain at night may be sorted out with a single-session filling, or it may extend to root canal treatment, extraction and an implant; the difference between them is large. The right figure can only be given once the X-ray has been seen. These are the items that determine the price:

The source of the pain

A filling, root canal treatment, draining an abscess and an extraction are different procedures, with different timescales, materials and numbers of sessions. A figure given before the source has been identified is bound to change at the clinic.

Where the tooth is in your mouth

A front tooth has a single canal, while a molar has three or four. As the number of canals goes up, so do the time the procedure takes and the materials used.

What goes on top

Crowning a tooth after root canal treatment is an inseparable part of the treatment and a real item of the cost. The material of the crown and the laboratory work have a direct effect on the total.

The next plan if the tooth cannot be saved

A single-tooth implant and a fixed plan covering the whole mouth are calculated separately. For patients who decide before the bone has shrunk, the extra surgery item never comes into play.