Introduction to Fixed Prosthodontics
- Branch of prosthodontics focused on permanently affixed dental prostheses
- Examples include crowns, bridges, inlays, onlays, and veneers
- Prosthodontists are dentists specialised in fixed prosthodontics
- Advantages include improved strength in large restorations and aesthetic appearance
- Selection of suitable repair involves consideration of materials, tooth destruction, placement, and neighboring teeth

Preparation Techniques and Dimensions
- Irreversible removal of tooth structure during crown preparation
- Restorations have impaired structural and functional integrity compared to natural teeth
- Treatment planning and recommendations may vary among dentists
- Crown and bridge work traditionally requires multiple visits
- Benefits of intervention generally outweigh the drawbacks
- Amount of tooth structure removal depends on the restoration material
- Full gold crown requires minimum tooth reduction of 0.5mm
- Porcelain application to gold crown requires additional 1mm of tooth structure removal
- Porcelain or ceramic crowns require 2mm of tooth reduction
- Insufficient tooth structure may require build-up material or post and core

Taper and Margin
- Prepared tooth needs a certain degree of taper for proper placement of the restoration
- No undercuts should be present on the prepared tooth surface
- Excessive taper limits the grip of the crown on the tooth
- Recommended taper is 3° around the entire circumference of the prepared tooth
- Combined taper of 6° provides proper fit and grip for the crown
- Margin is the most coronal position of untouched tooth structure
- Margin should be smooth and well-defined for proper adaptation of the restoration
- Acceptable distance from tooth margin to restoration margin is 40 to 100 nm
- Margin placement in aesthetic zone should be as apical as possible
- Violation of biologic width may occur if the margin is placed too subgingivally

Ferrule Effect
- Incorporation of the ferrule effect is crucial when restoring with a crown
- The crown should envelop a certain height of tooth structure to protect the tooth
- Similar to the grasping of bristles by a ferrule on a broomstick

Restoration Types
- Crowns are used to cover teeth and may be referred to as caps
- Teeth to be crowned are prepared by a dentist
- Dental technician constructs the crown using models and impressions
- Crowns can be made of gold, porcelain, or a combination of the two
- Zirkonia Oxide crowns are gaining popularity due to their translucency and durability
- Bridges are used to span edentulous areas by connecting to adjacent teeth
- Teeth supporting the bridge are called abutments
- Bridges can also refer to single-piece multiple-unit fixed partial dentures
- Part of the bridge replacing a missing tooth is known as a pontic
- Some cases may have several pontics for multiple missing teeth
- Inlays are restorations that lie within the cusps of teeth
- Considered more conservative than onlays or crowns
- Less tooth structure is removed during preparation
- Used when tooth destruction is less than half the distance between cusp tips
- Onlays cover, protect, or reinforce one or more cusps of teeth
- Indirect method for restoring teeth
- Used for extensive tooth destruction due to caries or trauma
- Provide more coverage than inlays
- Preserve more natural tooth structure compared to crowns

Fixed prosthodontics is the branch of prosthodontics that focuses on dental prostheses that are permanently affixed (fixed). Crowns, bridges (fixed dentures), inlays, onlays, and veneers are some examples of indirect dental restorations. Prosthodontists are dentists who have completed training in this specialty that has been recognised by academic institutes. Fixed prosthodontics can be used to reconstruct single or many teeth, spanning tooth loss areas. The main advantages of fixed prosthodontics over direct restorations are improved strength in big restorations and the possibility to build an aesthetic-looking tooth. The concepts utilised to select the suitable repair, as with any dental restoration, include consideration of the materials to be used, the level of tooth destruction, the orientation and placement of the tooth, and the condition of neighboring teeth

A good source of information about this subject can be found at The Journal of Prosthetic Dentistry

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