Zirconia Crowns Preparation Guidelines: A Simple Guide

Hi friends! Today we will talk about zirconia crowns. We will learn how to get them ready for your mouth. This guide will help you know what makes a good zirconia crown.

What Are Zirconia Crowns?

Zirconia crowns are tooth caps made from a very strong material. They look like real teeth and last a long time.

Zirconia can be used in two ways:

• Full zirconia (one solid piece)
• Layered zirconia (zirconia inside with pretty porcelain outside)

When we make a good zirconia crown, it needs to be cut just right. Let’s see how!

Basic Rules for Cutting Teeth for Zirconia Crowns

How Much Tooth to Remove

You need to take off the right amount of tooth:

• Top of tooth: Take off 1.5-2.0 mm
• Sides of tooth: Take off 1.0-1.5 mm
• Make all corners round so the crown won’t crack

Here’s a simple chart:

Edge Shape Matters

The edge where your crown meets your tooth is very important:

• Make a round shoulder or chamfer edge (120-160 μm wide)
• No sharp angles or points
• This helps the crown sit better and not chip

Wall Angle

Your tooth walls should have a slight slope:

• Make walls that lean in at a 6-12° angle
• This helps the crown stay put and lets the cement flow well

Back teeth need extra care when preparing for zirconia crowns.

Different Types Need Different Cuts

Full Zirconia (Monolithic)

For solid zirconia crowns:

• Cut more space for back teeth and people who grind
• Need at least 0.3-0.5 mm extra space all around for polishing
• These are great for strong, long-lasting crowns

Full contour zirconia works well for both front and back teeth.

Layered Zirconia

For pretty front teeth:

• Cut more from the biting edge (up to 2.5 mm)
• This makes room for the porcelain layer on top
• These look more like real teeth but can chip more

Digital Scans Help

When you use computer scans:

• They check if you have enough space (within 0.1 mm)
• Show where you need to cut more
• Help get a better fit

Sticking Zirconia Crowns in Place

Getting the Surface Ready

Before you put in the crown:

• Blast the inside with tiny sand bits (50 μm alumina at 2-3 bars)
• Use a special primer that has MDP in it
• This helps the crown stick better

Picking the Right Glue

The type of cement matters:

• Resin cement (sets with light and chemical) works best for most cases
• RMGI cement is good when the tooth is very short

Here’s what different cements do:

Important Steps

When putting in the crown:

• Keep the area dry
• Clean the crown inside with alcohol
• Wipe away extra cement right away

Professional labs can help ensure your zirconia restorations meet all requirements.

Big Mistakes to Avoid

Watch out for these common problems:

❌ Cutting Too Much Tooth

• Don’t go below 1.0 mm on the sides
• This makes the zirconia too thin and weak

❌ Flat Edges

• Don’t make flat or sharp edges
• They cause tiny cracks that grow bigger

❌ Getting the Crown Wet

• Water ruins the glue
• Keep everything very dry when putting in the crown

Working With Your Lab

Sharing Information

Help your lab make better crowns:

• Send pictures and scans so they see the edges
• Tell them what shade and see-through level you want

Getting Expert Help

• Find labs that give you tips on your tooth cutting
• They can spot problems before the crown is made

Layered zirconia crowns require special communication with your lab for best results.

Case Example

Dr. Smith had a patient with a broken back tooth. He cut the tooth with:

• 1.5 mm off the top
• 1.2 mm off the sides
• Round shoulder edges all around
• 8° wall slope

The zirconia crown fit perfectly and looked great. The patient was happy because it looked like a real tooth and felt strong when chewing.

Final Tips

For the best zirconia crowns:

1. Cut the right amount of tooth
2. Make round edges and corners
3. Use the best glue for your case
4. Keep everything dry when putting in the crown
5. Work closely with your dental lab

Remember: Good cutting + good glue = strong, pretty crown that lasts a long time!

Wrap Up

Now you know the key steps to make a zirconia crown work well. When you follow these rules, you get crowns that:

• Look like real teeth
• Are very strong
• Last many years
• Make your patients happy

Need more help with your dental work? Our lab is ready to help you make the best crowns for your patients!