Teeth play an important role in chewing, speaking and maintaining the appearance of your smile. However, decay, fractures, wear and tooth loss can affect their function and appearance.

Dental crowns and bridges are commonly used to restore damaged teeth and replace missing teeth. Although both are fixed restorations, they serve different purposes.

What are dental crowns and bridges?

Dental crowns and bridges are fixed prosthetic restorations designed to restore or replace teeth. They are usually made in a dental laboratory or using digital dental manufacturing techniques and are fitted by a dentist.

• Crown: Covers and restores an individual damaged tooth or an appropriately prepared dental implant abutment.
• Bridge: Replaces one or more missing teeth by connecting an artificial tooth to supporting teeth or implants.

What is a dental crown?

A dental crown is a custom-made restoration that covers the visible portion of a tooth. It is designed to restore the tooth's shape, strength, appearance and chewing function.

A dentist may recommend a crown in situations such as:

• A tooth with extensive decay and insufficient structure for a predictable direct filling.
• A tooth weakened by a large existing restoration.
• A fractured or severely worn tooth that can still be restored.
• Selected teeth following root canal treatment.
• Improving the shape or appearance of a suitable tooth.
• Restoring a dental implant with an implant-supported crown.

What is a dental bridge?

A dental bridge is a fixed restoration used to replace one or more missing teeth. In a conventional tooth-supported bridge, the artificial replacement tooth, called a pontic, is supported by crowns placed on prepared teeth on either side of the gap.

Depending on the clinical situation, bridges can also be supported by implants or designed using other configurations.

Potential benefits include:

• Replacing missing teeth with a fixed restoration.
• Restoring chewing function.
• Improving the appearance of the smile.
• Helping restore the dental arch and tooth contacts.
• Providing an alternative to a removable partial denture in selected cases.

A bridge requires careful assessment of the supporting teeth, gum health, bite, span length and available bone if implant support is being considered.

What is the difference between a crown and a bridge?

The main difference is their purpose. A crown restores or covers a tooth, while a bridge replaces a missing tooth or teeth.

• A crown is generally used to restore an individual damaged tooth.
• A bridge replaces a gap using one or more artificial teeth.
• A conventional bridge uses supporting natural teeth, which usually need preparation.
• An implant-supported bridge uses dental implants for support instead of relying on natural teeth as bridge abutments.

What are the different types of dental crowns?

Crowns are available in several materials. The choice depends on the tooth's location, available space, bite, aesthetic expectations, remaining tooth structure and individual clinical requirements.

1. Zirconia crowns

Zirconia is a high-strength ceramic material used for dental crowns and bridges. It is available in different formulations, including monolithic and layered designs.

• Good strength and fracture resistance for suitable indications.
• Metal-free restorative option.
• Available in different shades and translucencies.
• Can be used for selected anterior and posterior restorations.

2. E.max or lithium disilicate crowns

Lithium disilicate is a glass-ceramic material known for its optical properties and natural-looking appearance. It is commonly considered for aesthetic restorations, especially in suitable anterior and selected posterior cases.

• Excellent aesthetic potential.
• Can be adhesively bonded in appropriate cases.
• Available in different translucency options.

3. Porcelain-fused-to-metal crowns (PFM)

PFM crowns have a metal substructure covered by a layer of porcelain. They combine a metal framework with a tooth-coloured outer surface and have been used in restorative dentistry for many years.

• Established restorative option.
• Can provide good strength and aesthetics.
• The metal framework may become visible near the gum line if recession occurs.

4. Full metal crowns

Full metal crowns are made from dental alloys and are known for their durability and wear resistance. They may be considered for selected posterior teeth where appearance is less important.

What are the different types of dental bridges?

1. Conventional fixed bridge

This bridge uses crowns on supporting teeth to hold the replacement tooth or teeth in place. It may be considered when suitable adjacent teeth are available and the clinical conditions are favourable.

2. Cantilever bridge

A cantilever bridge is supported by an abutment or abutments on only one side of the missing tooth space. Because it can create unfavourable leverage, case selection and bite assessment are particularly important.

3. Maryland or resin-bonded bridge

A resin-bonded bridge generally uses a replacement tooth attached through metal or ceramic wings bonded to the back surfaces of neighbouring teeth. It can be a conservative option in carefully selected cases, particularly in the anterior region.

4. Implant-supported bridge

An implant-supported bridge is supported by dental implants rather than natural teeth. It can replace multiple missing teeth, depending on the number and position of implants and the restorative plan.

How are dental crowns and bridges placed?

The treatment process varies depending on the restoration selected. A conventional crown or bridge commonly involves the following stages:

1. Examination and treatment planning

Your dentist evaluates the tooth or missing tooth space, gum health, bite and supporting structures. Dental X-rays or other investigations may be recommended when clinically indicated.

2. Tooth preparation

For a conventional crown or bridge, the supporting tooth or teeth are shaped to create space for the restoration. The amount of preparation depends on the material, design and condition of the teeth.

3. Impression or digital scan

An impression or digital scan is recorded to capture the prepared teeth and surrounding structures. This information is used to fabricate the custom restoration.

4. Temporary restoration

A temporary crown or bridge may be placed to protect the prepared teeth and maintain function while the final restoration is being made.

5. Trial and final placement

The dentist checks the fit, contacts, appearance and bite of the restoration. Once suitable, it is cemented or bonded using the appropriate technique.

Why might a tooth need a crown after root canal treatment?

Root canal treatment removes inflamed or infected pulp tissue from inside a tooth. The tooth may already have significant structural damage from decay, fractures or previous restorations.

In teeth with substantial loss of structure, a crown or another suitable cuspal-coverage restoration may help protect the remaining tooth against fracture during chewing.

However, a crown is not automatically required after every root canal treatment. The decision depends on the tooth's location, remaining structure, crack status, restoration design and functional demands.

How long do dental crowns and bridges last?

Crowns and bridges can function for many years, but no restoration lasts forever. Their longevity depends on several factors:

• The material and quality of the restoration.
• Accuracy of fit and clinical execution.
• Oral hygiene and gum health.
• Biting forces and teeth grinding.
• Decay around the margins or supporting teeth.
• Regular dental reviews and timely maintenance.

A crown or bridge may need repair or replacement if it fractures, becomes loose, develops recurrent decay or loses adequate support. Regular dental examinations help identify problems early.

How should you care for dental crowns and bridges?

Good daily oral hygiene is essential to maintain the health of the teeth and gums supporting your restoration.

• Brush twice daily using fluoride toothpaste.
• Clean between natural teeth every day.
• Use floss threaders or interdental brushes to clean beneath conventional bridges.
• Avoid chewing ice or very hard objects.
• Discuss a night guard with your dentist if you grind your teeth.
• Attend regular dental check-ups.
• Report looseness, discomfort, bleeding gums or changes in your bite.

Are dental crowns and bridges painful?

The procedure is generally performed under local anaesthesia when needed, so tooth preparation should be comfortable. Some temporary sensitivity or gum tenderness may occur after treatment.

Once the final restoration is placed, it should feel comfortable when biting. If you experience persistent pain, a high bite, looseness or swelling, contact your dentist for assessment.

Frequently asked questions

Final thoughts

Dental crowns and bridges are important restorative options for rebuilding damaged teeth and replacing missing teeth. Choosing the right restoration requires careful evaluation of tooth structure, supporting tissues, bite and aesthetic needs.

With appropriate treatment planning, good oral hygiene and regular dental maintenance, these restorations can help restore comfortable chewing and improve the appearance of your smile.

This article is for general patient education and does not replace a clinical examination, diagnosis or individual treatment advice.