Module 4 Crowns and Bridges Part 1

What is fixed prosthodontics?

A dental specialty that replaces missing teeth or parts of teeth with restorations that are cemented and cannot be removed by the patient.

What is an indirect restoration?

A restoration fabricated outside the mouth (in a lab or in-office machine) and later cemented in the mouth.

What are examples of indirect restorations?

Inlays, onlays, veneers, crowns, and bridges.

Who performs fixed prosthodontics?

Dentists and prosthodontists (specialists with 3 additional years of training).

Why restore teeth with fixed prosthetics?

• Restores chewing function,

• improves esthetics and self-esteem,

• improves speech,

• promotes oral hygiene,

• prevents tooth movement.

What patient information is needed before planning fixed prosthetics?

Detailed medical/dental history, intra/extraoral exams, diagnostic models, full-mouth X-rays, and photographs.

What are indications for fixed prosthetics?

One or two adjacent missing teeth, healthy tissues, good abutment teeth, good general and oral health, and patient motivation.

What are contraindications for fixed prosthetics?

Poor supportive tissues, no suitable abutment teeth, poor health, poor oral hygiene, or inability to afford treatment.

Are fixed prosthetics direct or indirect restorations?

Indirect.

Why are fixed prosthetics considered indirect restorations?

They require impressions, temporary restorations, lab fabrication, and cementation at a later appointment.

What is an inlay?

An indirect restoration that covers occlusal and proximal surfaces of a tooth.

What is an onlay?

An indirect restoration that covers proximal surfaces and most or all of the occlusal surface, including cusps.

What is a crown?

A single-unit restoration that fully or partially covers a tooth with extensive breakdown or esthetic needs.

When is a crown indicated?

When too much tooth structure is lost for a filling, for esthetic improvement, for endodontically treated teeth, or over implants.

What is a full coverage crown?

A crown that covers the entire coronal surface of the tooth.

What is a partial crown (three-quarter crown)?

A crown that covers three or more surfaces while leaving the facial surface intact.

What is a PFM crown?

Porcelain-fused-to-metal crown: metal base covered with porcelain for strength and esthetics.

What is an all-ceramic/porcelain crown?

A metal-free crown made entirely of ceramic material for high esthetics.

What is a bridge?

A multi-unit restoration that replaces one or more missing teeth by anchoring to adjacent teeth.

What are the benefits of a bridge?

Replaces missing teeth, prevents drifting, maintains bone, restores chewing, and improves esthetics.

What are the components of a bridge?

Units, abutments (retainers), and pontics.

What is a unit in a bridge?

Each tooth or tooth-replacing component counted individually.

What is an abutment (retainer)?

A natural tooth or implant that supports the bridge.

What is a pontic?

The artificial tooth that replaces a missing tooth.

How do you name a bridge based on units?

Count both abutments and pontics (e.g., two abutments + one pontic = three-unit bridge).

What is a Maryland (resin-bonded) bridge?

A bridge with a pontic and metal or resin “wings” bonded to the lingual surfaces of adjacent teeth; ideal for single anterior replacements.

What is a cantilever bridge?

A bridge supported by only one abutment tooth, with the pontic extending off that abutment.

What is the main risk of a cantilever bridge?

Forces may stress the single abutment tooth.

What materials are used for fixed prostheses?

Ceramics (porcelain, zirconia), composites, and metals.

What is the benefit of using metal under a crown (e.g., PFM)?

Provides strength, durability, and support for porcelain.