Dental Crown (Tooth Cap) Overview
A dental crown is a tooth-shaped cap that covers a damaged, decayed, or weakened tooth to restore its shape, size, strength, and appearance.
What is a Dental Crown?
A dental crown is a permanent restoration that encases the entire visible portion of a tooth above the gum line. 1 The crown essentially becomes the tooth's new outer surface, providing protection and restoring function. 2
Types of Crowns Available
Metal-Ceramic Crowns
- Most commonly selected restoration combining the strength of cast metal with the aesthetic qualities of porcelain 3
- Offers great flexibility in metal selection for color or strength 3
- Provides excellent versatility for both single units and fixed partial dentures 3
All-Ceramic Crowns
- Excellent choice when anterior esthetics are the prime concern 3
- Multiple systems available depending on strength demands and esthetic needs 3
- Newer reinforced ceramics (like lithium disilicate) allow for more conservative preparation designs 4
Stainless Steel Crowns (Preformed Metal Crowns)
- Primarily used for primary (baby) teeth in children 5
- Can be fitted conventionally or using the Hall Technique (no tooth preparation required) 5
- May have white veneer covers for improved aesthetics 5
When Crowns Are Needed
For Permanent Teeth
- After root canal therapy on mature teeth - crowns are the standard restoration following pulp treatment 6, 7
- Crown-root fractures requiring orthodontic extrusion and subsequent restoration 6
- Teeth with extensive decay or large fillings that compromise structural integrity 1
- Severely broken down teeth requiring full coverage 2
For Primary (Baby) Teeth
Crown Placement Process
Tooth Preparation Requirements
- Adequate shoulder width and emergence profile must be created 2
- Sufficient tooth structure removal to accommodate material thickness while preserving as much healthy tooth as possible 4
- Balance between adequate preparation for material strength and enamel preservation 4
- Preparation design is crucial for restoration longevity 4
Material Selection Considerations
- Strength requirements - posterior teeth with heavy occlusal forces need stronger materials 3
- Esthetic demands - anterior teeth may prioritize appearance over maximum strength 3
- Amount of remaining tooth structure 3
- Degree of tooth discoloration (heavy staining requires more opaque core materials) 3
- Laboratory support availability 3
Clinical Outcomes and Success
For Primary Teeth
- Crowns show significantly lower risk of major failure compared to fillings (RR 0.18,95% CI 0.06 to 0.56) in long-term follow-up 5
- Lower risk of pain in the long term compared to conventional fillings (RR 0.15,95% CI 0.04 to 0.67) 5
- Hall Technique crowns cause less discomfort during placement than fillings (RR 0.56,95% CI 0.36 to 0.87) 5
For Permanent Teeth
- All-ceramic crowns demonstrate high clinical success rates 4
- Veneer crowns (extended veneers covering entire tooth) show promising outcomes with proper case selection 4
Important Considerations
Case Selection Factors
- Occlusal forces - ceramic crowns work best in anterior regions with lighter forces 3
- Absence of parafunctional habits (grinding, clenching) for ceramic restorations 3
- Adequate remaining enamel substrate, especially for bonded restorations 4
- Patient's canine guidance occlusion pattern 4
Common Pitfalls to Avoid
- Do not confuse crown-root fractures with simple root fractures - crown-root fractures require fragment removal first, not splinting 6
- Insufficient preparation depth compromises material strength 4
- Over-preparation removes excessive healthy tooth structure 4
- Using ceramic crowns in high-stress posterior areas without proper case selection 3
Follow-Up Monitoring
Monitor for these complications: