Lost a Filling or Crown? 5 Steps to Protect Your Tooth Until You See a Dentist

A filling or crown coming loose can be an unsettling experience, particularly if it happens unexpectedly whilst eating or during the night. You may notice a sudden change in the way your tooth feels, increased sensitivity, or a gap where the restoration once sat. Whilst the situation can feel urgent, understanding what has happened and taking a few simple precautions can help protect the tooth until you are able to see a dentist.

This guide explains why dental fillings and crowns can become dislodged, what happens to the tooth once a restoration is lost, and practical steps you can take at home to reduce discomfort and minimise the risk of further damage.

Why Do Fillings and Crowns Come Loose?

Fillings and crowns are designed to restore the structure and function of a damaged tooth, but they are not permanent fixtures. Over time, the bond between a restoration and the underlying tooth can weaken for a number of reasons.

General wear and tear is one of the most common causes. The forces generated during chewing, grinding, or clenching place continuous stress on restorations, and over the course of several years this can gradually compromise the seal. Secondary decay — new decay that develops around the margins of an existing filling or beneath a dental crown — can also undermine the fit of a restoration, causing it to loosen or fall out.

Biting into particularly hard or sticky foods, trauma to the mouth, or habitual teeth grinding (bruxism) can also contribute. In some cases, the tooth structure itself may have weakened over time, reducing the support available for the restoration.

What Is Dentin and Why Does Exposure Matter?

Beneath the hard outer enamel of a tooth lies a layer called dentin. Dentin is a porous, yellowish tissue that makes up the bulk of the tooth's structure. Unlike enamel, which is highly mineralised and acts as a protective shield, dentin contains thousands of microscopic tubules — tiny channels that connect to the nerve at the centre of the tooth.

When a filling or crown is lost, the dentin that was previously protected becomes exposed. This exposure can result in heightened sensitivity to temperature changes, sweet foods, and pressure. More importantly, exposed dentin is softer and more porous than enamel, which means it can be more susceptible to bacterial penetration and the progression of decay.

Without the protective barrier of a restoration, bacteria from the mouth may begin to accumulate in the exposed area. Over time, this can lead to further decay, infection of the dental pulp, or in some cases, the development of an abscess. The longer the tooth remains unprotected, the greater the risk of complications that may require more extensive treatment.

Is a Lost Filling or Crown a Dental Emergency?

A lost filling or crown is not always classified as an emergency in the same way as uncontrolled bleeding or facial swelling, but it does generally warrant timely attention. The exposed tooth is vulnerable, and delaying assessment can sometimes allow a manageable situation to become more complex.

If you are experiencing significant pain, signs of infection such as swelling or a persistent bad taste, or if a large portion of the tooth has broken away, it may be appropriate to seek an urgent assessment from an emergency dentist in London. In less severe cases, booking an appointment within a few days is often a reasonable approach, provided you take steps to protect the tooth in the meantime.

5 Steps to Protect Your Tooth at Home

Whilst professional treatment is always the appropriate solution for a lost filling or crown, there are several practical measures you can take at home to protect the tooth and manage discomfort until your appointment.

Step 1 — Keep the Area Clean

Gently brush the affected tooth and the surrounding area to remove food debris and reduce bacterial accumulation. Use a soft-bristled toothbrush and be careful not to apply excessive pressure, as the exposed surface may be sensitive. Rinsing with warm salt water — approximately half a teaspoon of salt dissolved in a glass of warm water — can also help keep the area clean and may provide mild soothing relief.

Step 2 — Avoid Hot, Cold, and Sugary Foods

Exposed dentin is particularly responsive to temperature extremes and sugar. Hot drinks, ice-cold beverages, and sweet foods can trigger sharp discomfort through the exposed tubules in the dentin. Sticking to lukewarm foods and drinks, and avoiding sugary items, can help reduce sensitivity and limit the conditions that encourage bacterial activity.

Step 3 — Chew on the Opposite Side

Directing chewing forces away from the affected tooth can help prevent further damage. A tooth that has lost its restoration may have weakened walls, and biting down on hard foods could cause additional fracturing. Using the opposite side of the mouth for eating is a simple but effective precaution until the tooth has been professionally assessed.

Step 4 — Use Sugar-Free Gum as a Temporary Cover

If the cavity left by the lost filling is causing significant sensitivity, a small piece of sugar-free chewing gum can be gently pressed into the space as a temporary barrier. This is not a substitute for professional treatment and should be regarded as a very short-term measure only — typically to provide relief for a few hours or overnight until you can see a dentist. Do not use regular chewing gum, as the sugar content could contribute to further decay.

Step 5 — Save the Crown If Possible

If a crown has come off intact, keep it in a clean, safe place and bring it to your dental appointment. In some cases, a dentist may be able to re-cement the existing crown, provided the underlying tooth structure remains sound. Avoid attempting to glue the crown back in place yourself using household adhesives, as these can damage the tooth and the restoration. Over-the-counter temporary dental cement, available from most pharmacies, can be used as a short-term measure if recommended by your dental practice.

How Long Can a Tooth Be Left Without a Filling?

There is no fixed timeframe, as the risk depends on several factors including the size of the cavity, whether the tooth is causing symptoms, and the patient's overall oral health. However, leaving a tooth unprotected for an extended period is generally not advisable.

Without a restoration, the exposed dentin is continuously vulnerable to bacteria and mechanical forces. In some cases, decay can progress relatively quickly, particularly if oral hygiene is compromised or the diet includes frequent sugar exposure. What may initially require a straightforward filling replacement could, over weeks or months, develop into a situation requiring root canal treatment, a crown, or in more advanced cases, extraction.

Seeking assessment within a few days of losing a filling or crown is generally a sensible approach. If pain, swelling, or signs of infection develop, earlier assessment may be appropriate.

What Professional Treatment May Involve

The treatment required after losing a filling or crown depends on the condition of the underlying tooth. During your appointment, a dentist will examine the tooth, assess any decay or structural damage, and discuss the most appropriate options.

If the tooth remains structurally sound and there is no significant new decay, a replacement filling — commonly a tooth-coloured composite restoration — may be all that is needed. For a lost crown, the dentist may be able to re-cement the original crown if it is undamaged and the tooth beneath is intact.

In cases where decay has progressed or the tooth has fractured, more extensive treatment may be recommended. This could include a new crown to restore strength and protection, or root canal treatment if the pulp has become infected or inflamed. The dentist will explain the available options and provide a clear treatment plan before proceeding.

When Should I See an Emergency Dentist?

Whilst a lost filling or crown can often be managed within a routine or short-notice appointment, certain symptoms may indicate that more urgent assessment is appropriate. You may wish to seek prompt dental advice if:

• You are experiencing severe or worsening pain that is not controlled by over-the-counter pain relief
• There is visible swelling of the gum, face, or jaw
• You notice a persistent unpleasant taste or discharge from the affected tooth
• A large portion of the tooth has broken away, leaving sharp edges
• The affected tooth has become very loose

These signs can sometimes indicate infection, pulp involvement, or structural compromise that may benefit from earlier intervention. If you are uncertain about the severity of your situation, contacting a dental practice for advice is always a reasonable step.

Summary

Losing a filling or crown is a common dental occurrence that, with prompt and appropriate care, can usually be resolved without complication. The key priorities are to protect the exposed tooth from further damage, manage sensitivity through simple at-home measures, and arrange a professional assessment within a reasonable timeframe.

Understanding that exposed dentin is vulnerable to bacteria and decay can help you appreciate why timely attention matters, even if the situation does not feel immediately painful. The five steps outlined in this guide — keeping the area clean, avoiding temperature extremes and sugar, chewing on the opposite side, using sugar-free gum as a temporary cover, and saving a dislodged crown — can provide practical protection in the short term.