Extra coronal restorations and crowns Flashcards
what is a crown
What does taper mean
what is the height of crown mean
what is a core
Build up teeth by composite core
Completely enclose within crown
Build tooth up and then cut it down to accept crown at top
what are the 3 types of crown
what are the advantages of FVC
Look at occlusal reductions
Prepare teeth with different dimensions
Lost wax technique
what are the disadvantages of FVC
what are indications for FVC
what is the FVC die preparation
describe FVC model and die preparation
what is the lost wax preparation
- cusps built up to bring tooth to correct occlusion
- contact points created and cusps added to bring the tooth into the correct occlusion
what are advantages of MCC
what are MCC disadvantages
describe advantages of ACC
describe CAD/CAM workflow
What is a crown in dentistry?
A crown is a restoration that is constructed outside the mouth and designed to encompass the entire tooth, like a helmet for the tooth! 🦷👑🎩
What does “taper” refer to in crown preparation?
Taper is the degree of convergence of the walls of the crown preparation, meaning how much the tooth prep slopes towards the top. 🧰📐
What is the “height” of a crown preparation?
The height is the distance from the margin to the occlusal/incisal surface of the tooth prep. 📏📐
What is the role of luting cement?
Luting cement is used to bond the crown to the tooth, enhancing its strength and stability. 🧴💪💥
What is retention in crown preparation?
Retention refers to designing the prep to prevent the crown from slipping off or twisting. Avoid too much taper! 🚫🔧🔒
What is a composite core in crown preparation?
A composite core is used to build up a tooth to fit better inside the crown. It’s like a foundation to hold the crown in place. 🏗️🛠️
What is a cast post and core used for?
It’s used after Root Canal Treatment (RCT) to give a foundation for a metal-ceramic crown. 🦷💍⚙️
What are the advantages of a Full Veneer Crown (FVC)?
FVCs are strong, have similar hardness to enamel, and require minimal tooth reduction. 💪🦷✨
What are the disadvantages of a Full Veneer Crown (FVC)?
FVCs may lack aesthetics (especially gold crowns), and gold is expensive. Also, gold doesn’t bond to the tooth well. 💰🚫😬
When would you use a Full Veneer Crown (FVC)?
FVCs are ideal for posterior teeth where aesthetics are less of a concern and for teeth with limited height. 🦷💡
Describe the lost wax technique used in FVC manufacturing.
Crown model made from an impression.
Tooth is separated from the model using a thin saw blade to create a single die. 🔪
Trim the die to expose the prepared margin. 🛠️
Add a die spacer in layers to create room for luting cement.
Wax pattern is built up to recreate natural tooth anatomy (making it look like a real tooth!). 🖌️
Sprue former helps molten metal flow into the mold. 🏗️
The wax pattern is placed in a mold and melted away to leave an empty space for the metal. 🔥
The molten metal is forced into the mold, creating a metal alloy version of the wax pattern. 🔩
Lab polishes the unpolished metal crown into a shiny finish. ✨
Contact points checked to make sure everything fits correctly. 🔍
What are the types of crowns?
The main types of crowns are:
Full Veneer Crown (FVC)
Metal-Ceramic Crown (MCC)
All-Ceramic Crown (ACC) 🦷✨
What is the main advantage of a Metal-Ceramic Crown (MCC)?
MCCs are strong and durable, making them ideal for molars. 💪
What is a major disadvantage of Metal-Ceramic Crowns (MCC)?
The porcelain layer must be thicker to cover the metal base, leading to more tooth preparation and potentially a less aesthetic result. 😬
How do you create a Metal-Ceramic Crown?
The process includes:
Creating a wax pattern for the metal substructure. 🖌️
Spruing and trimming the metal. 🔥
Adding porcelain layers for aesthetics. 🎨✨
Cementing the crown onto the prepared tooth. 🦷🛠️
What is an All-Ceramic Crown (ACC) made from?
Lithium disilicate (e.MAX), which is strong, has great aesthetics, and is made using either lost wax technique or CAD/CAM technology. 💎🖥️✨
What is the CAD/CAM workflow for creating an All-Ceramic Crown?
Scan the prepared tooth. 🖥️
Design the crown using computer software. 💻
Mill the crown using a machine. 🏗️
Try the crown on the model, check contacts. ✅
Cement the final crown. 🦷💥
What are the advantages of All-Ceramic Crowns (ACC)?
They are aesthetic, strong, and can be made quickly using CAD/CAM in one visit! 🏃♀️✨🦷
What is the role of luting cement in crown placement?
It bonds the crown to the tooth, making everything stronger and securely in place. 🧴💪💥
What are the types of luting cements used for crowns?
Resin-based: Strong, ideal for ceramic crowns. 💎
Glass Ionomer: Used for temporary crowns. ⏳
Zinc Phosphate: Traditional cement, less used today. ⚙️
What are the steps for crown preparation?
Tooth Reduction: Shape the tooth to fit the crown. 🪓🔪
Impression: Take an accurate impression. 📸👀
Temporary Crown: Place a temporary crown while waiting for the permanent one. 🕰️💍
Why might a partial veneer crown be used?
It covers only part of the tooth, ideal when there’s less damage and for conserving tooth structure. 🌱💎🦷
What is the purpose of the wax pattern in crown manufacturing?
The wax pattern is created to replicate the natural anatomy of the tooth, which is later converted into a metal alloy or ceramic crown. 🖌️🔥💍
What does CAD/CAM stand for?
Computer-Aided Design/Computer-Aided Manufacturing. It allows for digital design and milling of crowns in the dental office. 💻🔧🦷
: What is the main difference between Full Veneer Crowns (FVC) and Metal Ceramic Crowns (MCC)?
FVCs are made entirely from metal (gold or non-precious metal) and are ideal for posterior teeth. In contrast, MCCs have a metal substructure with a porcelain layer for aesthetic appeal, making them better suited for anterior teeth. 🦷💍🦷
How is the All-Ceramic Crown created using CAD/CAM?
Scan the tooth prep. 📸
Design the crown on the computer. 💻
Mill the crown from a ceramic block. 🛠️
Try the crown, check fit. ✅
Cement the final crown. 🦷✨
What happens if too much taper is applied during crown preparation?
If too much taper is applied, the crown might not fit properly, and it can lead to loss of retention. The crown may twist or come off, so it’s important to avoid excessive taper. 🔧⚖️🦷
