Temporary crowns: what are they for, how long do they stay, and what if one falls out?

The Oral Health Foundation explains that a crown is usually made over two appointments: at the first, the tooth is shaped to make room for the crown, an impression or digital scan is taken and a temporary crown is fitted to protect the tooth; the real crown is made in the laboratory. At the second appointment, the temporary crown is removed, the fit and comfort of the new crown are checked and it is cemented permanently. According to the Foundation, some ceramic crowns can be designed by computer and made on the same day; in that case a temporary crown is not needed at all.

A prepared tooth cannot be left exposed. For a crown, enamel and dentin are removed from the outer surface of the tooth, and in a living tooth the tiny channels leading to the nerve inside are exposed. A review published from Japan lists the job of a temporary restoration as follows: protecting the tooth to be crowned and the gum around it until the permanent crown arrives, maintaining chewing function and the shape of the tooth, and preserving the bite relationship with the opposing tooth. Without a temporary crown, the tooth becomes sensitive to cold, heat and sweet things, plaque builds up at its edges and the gum becomes irritated.

Preserving the bite is the least known but most important job. When a prepared tooth does not touch the opposing tooth, teeth can drift into the gap over time, or the opposing tooth can over-erupt. Even within a few weeks this can be enough to spoil the fit of the real crown made in the laboratory; when the crown arrives, it does not seat or it is too high when you bite. The same review stresses that even though a temporary restoration is used for a short time, when its importance is overlooked, the success of the real crown is affected too.

A temporary crown also has a trial function. A review in an American dental journal states that temporary restorations are both a diagnostic aid and a biological and mechanical part of treatment, and that on front teeth they are also used to assess how the real crown will look. If you do not like the length, colour or shape of a temporary crown on a front tooth, tell your dentist; this information can be reflected in the design of the real crown.

A temporary crown is deliberately cemented weakly. The dentist uses a temporary cement so that it can be removed a few weeks later without harming the tooth. Its material is also a resin that is softer and more brittle than the real crown. This is why it falling out, cracking or wearing at the edge can be considered normal; but when it is left in the mouth for a long time, these weaknesses work against the tooth. The Oral Health Foundation gives the same warning for temporary fillings: they last less long, can wear down or fall out, and should not be used in place of permanent treatment.

On what to do when one falls out, the fact sheet prepared for pharmacists by Health Education England sets out a clear sequence. The pharmacist first asks whether the crown sits comfortably on the tooth without falling off, whether the tooth has broken inside the crown and whether the sharp edge of the remaining tooth is causing a sore on the cheek or tongue. If the crown sits firmly, it can be re-cemented with a temporary crown cement kit, or the exposed part of the tooth can be covered with a temporary filling kit. The fact sheet states that this is the least preferred option, that assessment by a dentist is needed in every case and that with severe pain, swelling or infection, urgent dental advice is essential.

In implant treatment, temporary teeth mean something a little different. In conventional implant treatment, the implants are left unloaded for 3 to 8 months so that they fuse with the bone; during this time the patient usually wears a temporary denture or a temporary crown and bridge, and the permanent teeth are made after fusion. In Implant72's full-mouth protocol, by contrast, the implants and the final fixed teeth are completed in 3 days, and the teeth fitted on day 3 are the final teeth; they are not removed months later and replaced with a permanent bridge. The temporary crown described above is the interim solution used when a crown is being made for a single natural tooth.

The first list shows situations you can manage at home for a short time until you reach your dentist, and the second list situations that need same-day or emergency assessment. Every problem with a temporary crown is ultimately for your dentist to deal with; it is the field not of this clinic but of the dentist who made the crown.

The sequence first separates out an emergency, then shows what can safely be done at home and what you should have with you when you go to the dentist.

1. 1

   First, check for emergency signs

   If there is swelling around the eye or in the neck, or difficulty swallowing, speaking or breathing, call 112 or go to A&E. If there is severe pain, a fever or swelling in the cheek, contact a dentist the same day.

2. 2

   Find, clean and keep the crown

   If you have not swallowed it, find the crown, gently clean any food debris and old cement from inside it and keep it in a small container. An intact temporary crown can often be reused; take it to your dentist.

3. 3

   Try whether it seats

   Place the crown on the tooth and, without biting, check whether it seats fully in place. This is the first question in the pharmacist fact sheet: does the crown sit comfortably without falling off? Do not force it; if it does not seat, the tooth may be broken.

4. 4

   If needed, cement it temporarily with a pharmacy kit

   If the crown sits firmly, it can be cemented back in place with a temporary crown cement kit sold in pharmacies; if it does not seat or has been lost, the exposed surface of the tooth can be covered with a temporary filling kit. Follow the kit's instructions. Do not use superglue or household glue; these can damage the tooth and the gum and make the crown harder to remove later. These kits are mentioned in the pharmacist fact sheet in England; in Turkey, whether pharmacies stock them may vary. If you cannot find one or are not sure, keep the crown, call your dentist and wait for the appointment.

5. 5

   For pain

   The fact sheet and the NHS mention painkillers such as ibuprofen or paracetamol; the NHS notes that children under 16 should not take aspirin and that a pharmacist can help with the dose. The American Dental Association also says that aspirin should not be placed on the aching tooth or gum.

6. 6

   Call your dentist

   The fact sheet states that assessment by a dentist is the best option in every case, and that because of pain and the risk of infection an appointment should be made as soon as possible. Your dentist can re-cement the crown, make a new one or, if the crown is ready, fit the real crown straight away.

A temporary crown is not the only option in every case. The following are different routes you can discuss with your dentist; which one is suitable depends on the condition of the tooth and the type of crown.

Because a temporary crown is a small piece, it is not taken seriously. The mistakes below can affect the fit of the real crown and the tooth itself.

The course below is a general framework for a conventional crown over two appointments. Timings vary with the type of crown and the laboratory; the date your dentist gives you takes priority.

1. The day it is fitted

   Do not eat until the numbness has worn off. The Oral Health Foundation recommends not chewing on that side for the first few hours with temporary fillings; the same care is sensible for a temporary crown.

2. The first few days

   There may be slight sensitivity to hot and cold. Do not stop brushing; clean gently around the crown with a soft brush and slide the floss out sideways.

3. The waiting period

   The real crown is being made in the laboratory. During this period, avoid hard, sticky foods and biting on that side; if it falls out or breaks, call your dentist without waiting.

4. Fitting the real crown

   The temporary crown is removed, the surface of the tooth is cleaned, and the fit and bite of the new crown are checked before it is cemented permanently.

We do not give figures here. A temporary crown is usually planned as part of crown treatment; whether a separate procedure is needed is decided by the items below:

Whether it is made in the chair or in the laboratory

Short-term temporaries are usually made in the mouth during the appointment; those that will stay in for a long time can be made in the laboratory.

How many times it has fallen out or broken

Re-cementing it or making a new temporary may need an extra appointment.

The waiting period

The real crown arriving late increases the chance of the temporary crown wearing out and needing to be replaced.

The same-day crown option

If the crown is made in a single appointment, a temporary crown is not needed at all; the Oral Health Foundation states that this often increases the cost.