Non-Precious

1. Zirconia Crowns and Bridges
Overview:
Zirconia is a durable ceramic material with remarkable physical properties, making it one of the most sought-after materials for crowns and bridges. Known for its combination of strength, aesthetic appeal, and biocompatibility, it is often chosen for patients who need both functional and natural-looking restorations.

Key Features:
Strength and Durability: Zirconia is known for its high flexural strength, making it suitable for posterior restorations, which endure greater masticatory forces.
Aesthetic Appeal: Unlike metal-based restorations, zirconia mimics the natural translucency of teeth, making it ideal for more visible areas like the anterior (front) teeth.
Biocompatibility: Being metal-free, zirconia promotes a healthy response from gum tissue and reduces the risk of allergic reactions, making it perfect for sensitive patients.
Low Coefficient of Thermal Expansion (CTE): This feature prevents the material from expanding or contracting too much with temperature changes, thereby reducing the potential for cracking or dislodging.
CAD/CAM Technology: Zirconia is often milled with CAD/CAM systems, ensuring a high degree of precision and reducing human error.
Benefits:
Long-Term Reliability: The material is designed to last, with proper oral hygiene, a zirconia crown can endure for 30+ years.
Healthy Tissue Integration: Due to its biocompatibility, zirconia crowns often lead to less irritation and inflammation in the gums.
Natural Look: Its translucent properties allow zirconia to blend seamlessly with natural teeth, making it an excellent choice for aesthetic restorations.
Hypoallergenic: Unlike metals, zirconia is suitable for patients with allergies or sensitivities to certain metals, particularly nickel or palladium.
Indications:
Posterior Crowns and Bridges: Zirconia is ideal for restoring teeth in the back of the mouth due to its strength and resilience.
Bruxism Patients: For patients who grind their teeth, zirconia can withstand the intense pressure caused by bruxism, offering a solution that reduces the risk of fracture.
Implants and Maryland Bridges: Zirconia can be used effectively for implant crowns and other partial bridges, providing both functional strength and aesthetic value.
Contraindications:
Highly Translucent Teeth: Zirconia might not be suitable for very translucent natural teeth, particularly for anterior restorations in the aesthetic zone. The material can appear too opaque, affecting the natural look.
Alloy Sensitivities: Zirconia is a metal-free ceramic, so it is suitable for individuals with sensitivities to metal-based restorations. However, patients who require metallic restoration may not benefit from zirconia.
Preparation and Cementation:
Prep Guidelines: To ensure that zirconia crowns fit perfectly, specific tooth reduction dimensions are essential:
Incisal/Occlusal: 2mm
Facial/Lingual: 1.5mm
Cervical: 1.2mm
Cementation: Standard conventional cementation techniques are typically used for zirconia crowns and bridges. These materials bond effectively with the cement, ensuring a strong and secure fit.
2. Metal-Alloy Crowns and Bridges
Overview:
Metal-alloy crowns and bridges have been a reliable choice in dentistry for over 60 years, primarily due to their durability, strength, and long-term performance. These restorations are made from a range of alloys, including high noble (precious), noble (semi-precious), and non-precious metals.

Key Features:
Strength and Durability: Metal alloys, especially high noble and noble alloys, provide exceptional strength and wear resistance. This makes them particularly suitable for posterior teeth that undergo significant stress from chewing.
Longevity: Metal restorations can last for decades with good oral hygiene, making them ideal for patients seeking long-lasting solutions.
Versatility: Alloys can be used for a variety of restorations, including single crowns, bridges, and implant crowns. Their strength makes them suitable for long bridges, even with multiple missing teeth.
Benefits:
Exceptional Durability: Metal alloys can withstand heavy occlusal forces and last for up to 30 years or more with proper care. This makes them one of the most durable dental restoration options.
Good Marginal Fit: Metal alloys provide a tight seal, reducing the risk of secondary caries (decay beneath the restoration).
Tried and Tested: With decades of use in dentistry, metal alloys are a proven solution that dental professionals trust for both aesthetic and functional purposes.
Affordable Option: Compared to ceramic restorations, non-precious alloys are a more cost-effective choice for patients on a budget while still providing robust performance.
Indications:
Anterior and Posterior Crowns: Both regions of the mouth benefit from metal alloys’ strength and durability, particularly when patients are dealing with larger restorations.
Bridges of Any Span: Metal alloys can be used for bridges that replace multiple missing teeth, especially in the posterior where high forces are involved.
Implant Crowns: Metal is often the go-to choice for crowns placed on dental implants due to its strength and ability to withstand the forces of mastication.
Crowns under Partials: Metal restorations are ideal for patients with partial dentures, as they provide the necessary support and function for the prosthesis.
Contraindications:
Aesthetic Concerns: Metal alloys can be opaque and may not blend well with highly translucent natural teeth, making them less ideal for anterior restorations.
Alloy Sensitivities: Some patients may be allergic to certain metals (like nickel), which would make them unsuitable candidates for non-precious alloys.
Preparation and Cementation:
Prep Guidelines: Similar to zirconia, metal alloys require precise tooth preparation:
Incisal/Occlusal: 2mm
Facial/Lingual: 1.5mm
Cervical: 1.2mm
Cementation: Metal alloys are typically cemented using conventional cementation techniques. Standard cements are used to ensure the long-term retention of the restoration.
Conclusion:
Both Zirconia and Metal-Alloy crowns and bridges are reliable, durable, and offer distinct advantages. Zirconia stands out for its aesthetic appeal and biocompatibility, making it ideal for patients with specific needs for appearance and those with sensitivities to metals. Metal alloys, on the other hand, offer unmatched strength and longevity, making them the go-to choice for patients who prioritize function and durability, particularly in the posterior regions of the mouth.

The decision between these materials depends on several factors, including the location of the restoration, the patient’s esthetic expectations, the bite forces, and whether the patient has any allergy concerns. A skilled dental professional will assess these factors to make the best choice for the patient’s unique situation.