Semi-Precious

Semi-Precious Alloy Restorations (DBS – Dental Basic Science)
Features:
Strong and durable
Versatile for various dental applications
Clinically proven for over 60 years
Available in high noble, noble (semi-precious), or non-precious alloys
Benefits of Semi-Precious Alloy Restorations
Excellent Marginal Integrity

Provides a tight seal at restoration margins, reducing microleakage and secondary caries risks.
Ensures long-term stability with precise fit.
High Strength and Durability

Suitable for high-stress areas, including posterior crowns and long-span bridges.
Resistant to fractures and chipping, unlike all-ceramic restorations.
Long Lifespan

With proper oral hygiene, restorations can last 30+ years.
Well-established and trusted material in clinical dentistry.
Certified and Reliable Alloys

Tried-and-tested materials conform to international standards.
Reliable for both natural teeth and implant-supported restorations.
Indications (When to Use Semi-Precious Alloy Restorations)
Indication Application
Anterior/Posterior Crowns Provides strength and function while allowing esthetic porcelain layering.
Bridges (Any Span) Suitable for short and long-span bridges, ensuring stability and durability.
Implant Crowns Ideal for implant abutments, offering long-term precision and stability.
Crown Under Partial Denture Works well as a support for removable partial dentures.
Contraindications (When Not to Use Semi-Precious Alloys)
Contraindication Reason
Highly Translucent Adjacent Teeth or All-Ceramic Crowns Semi-precious alloys require opaque porcelain, which may not match natural translucency.
Alloy Sensitivity or Metal Allergies Patients with metal allergies (e.g., nickel sensitivity) should consider alternatives like zirconia.
Tooth Preparation Guidelines
Area Reduction Required
Incisal/Occlusal 2.0 mm – Provides space for porcelain layering and strength.
Facial/Lingual 1.5 mm – Ensures proper material thickness.
Cervical Margin 1.2 mm – Recommended shoulder or chamfer for better adaptation and longevity.
Note: Proper preparation ensures optimal fit, strength, and durability while minimizing risks like pulp exposure.

Cementation Protocol
Recommended Cementation Materials
Conventional cementation is preferred for semi-precious alloy restorations:
Zinc phosphate cement – Time-tested reliability
Glass ionomer cement (GIC) – Fluoride release, good retention
Resin-modified glass ionomer cement (RMGI) – Stronger bond, better moisture resistance
Advantages of Conventional Cementation for Semi-Precious Alloys:
No need for adhesive bonding like all-ceramic restorations.
Ensures long-term retention with proper preparation design.
Less technique-sensitive than resin bonding.
Comparison with Other Materials
Feature Semi-Precious Alloy Zirconia (All-Ceramic) Non-Precious Alloy
Aesthetics Moderate (requires porcelain layering) High (natural translucency) Poor (visible metal color)
Strength & Durability High – withstands occlusal forces Very High – extremely strong but brittle in thin sections Moderate – prone to corrosion over time
Biocompatibility Good – low allergenic potential Excellent – ideal for sensitive patients Lower – may contain nickel or beryllium
Cost Moderate Higher – premium material Lower – budget-friendly option
Longevity 20-30 years 20-30 years 10-20 years
Best Use Case Crowns, bridges, implants Aesthetic zones, anterior crowns Budget restorations, posterior crowns
Final Recommendations
Semi-precious alloy restorations remain a reliable, durable, and cost-effective option in modern dentistry. They are ideal for:

✅ Patients needing long-lasting posterior restorations

✅ Bridges requiring strong framework support

✅ Implant crowns needing precise fit and function

✅ Cases requiring a balance of cost and performance

However, for highly aesthetic zones or patients with metal allergies, all-ceramic restorations (e.g., zirconia or lithium disilicate) may be better alternatives.