Appointment 1 – Preparation
Firstly, we take photographs and x-rays of your existing tooth to check the roots of your tooth and the health of the bone and surrounding teeth. If we discover that your tooth has extensive decay, or if there is a risk of infection or injury to your tooth’s pulp, it may be necessary to first perform a root canal treatment.
Next, we find the tooth shade for the crown so we can blend it in with your other teeth.
Next, we meticulously make a mould of your existing tooth so we can make a temporary crown. You’ll wear a temporary crown while your crown is being made at the laboratory. This helps protect the underlying tooth while the permanent crown is being made.
Preparing Your Tooth
Depending how strong your tooth is, we may place a post in your tooth to help support the crown. We use materials that are strong and flexible, similar to dentine (inner part of teeth). This post lowers the risk of root fracture and is set before the crown preparation begins.
Next we carefully contour the tooth to make room for the crown to fit on it. The amount of tooth we remove depends on the type of crown we’ll use. For example, metal crowns are generally thinner and need less of your tooth removed. Modern, aesthetic all-ceramic E-max crowns bond directly to your tooth and often require minimal tooth shaping as well.
We then place a fine braided cord around the base of your tooth. This cord gently pushes your gum away from the tooth. This allows us to take a detailed impression of the tooth, including margins for the crown. We remove it just before we take the impression.
Making the Mould
We then use two specially shaped impression trays over your upper or lower teeth. It takes two stages using impression material to make one complete impression for the crown.
Firstly, the dental assistant places a putty-like impression material called poly-vinyl-siloxane (PVS for short) into the impression tray.
While the dental assistant is filling the tray, the dentist places the thinner, flowable material over the prepared tooth and surrounding area. Then we carefully place the tray, filled with impression material, over the flowable material on the prepared tooth. This combined impression takes a few minutes to set.
The final impression shows all the surrounding teeth and the prepared tooth. The impression of the prepared tooth will show the details of the gum and every part of the prepared tooth.
Making the Temporary Crown
While we work on preparing your tooth for a dental crown, you are most welcome to enjoy a DVD, listen to music, and basically relax as we take care of the entire process.
Your dentist then makes a temporary crown using the template taken earlier. We place a thick, tooth-coloured material in the new template, and seat it onto the prepared tooth.
After the material sets. we remove the template, with the hardened material, now in the shape of a tooth.
Then we trim and polish the temporary crown. We also check your bite to ensure the crown fits properly.
Now we’re ready to cement the temporary crown into place to protect the preparation from breaking or chipping. This also protects your prepared tooth from sensitivity, as we may have had to remove some of the enamel coating of your tooth during the preparation process.
Normally the temporary cement is effective in holding the temporary crown to the prepared base. However, very hard or sticky foods can cause the temporary crown to come off.
Unfortunately it is not possible to cement a temporary crown with permanent cement. The temporary crown must be able to be easily removed so the finished crown can be placed. Using permanent cement might damage the tooth base during the removal of the temporary crown. This means the new crown might not fit properly.
The Crown Is Made
We now send the crown impression, any photographs taken and information about the tooth shade to the laboratory to create a perfectly fitting dental crown. We have crowns made by a local dental technician, whom we have worked with for many years. He uses only high-quality Australian or European materials, so only the best materials go into your crown. His years of experience producing excellent crowns means you have peace of mind knowing you’re getting a first rate product and service.
Approximately 2 weeks later, the new crown returns from the laboratory. We check it for quality, finish and fit on the model.
Appointment 2 – Fitting the Crown
We gently remove the temporary crown from the prepared base, along with any remaining cement residue.
We try the crown on the prepared tooth to check the fit, correct shade and bite (occlusion). Sometimes it is necessary to make a few minor adjustments e.g. to ensure you can floss between the crown and the surrounding teeth, or to make sure your bite is correct.
We then remove the crown and clean both the crown and the tooth with a solution to ensure the surfaces are free of any contaminants or moisture.
Finally, we apply permanent cement to the inside of the crown and place the crown on your prepared tooth. We check to be sure it is seated correctly into position.
If there is any excess cement, we remove it as this can be a potential irritant to your gum and hampers cleaning and flossing.
We check your bite one final time, ensuring your teeth are meeting comfortably.
We discuss with you the care of your crown and any special precautions you may need to take to ensure its long life and health.
How can I help ensure the crown is successful?
It is very important to keep teeth clean and free of plaque and calculus. As they accumulate, they can inflame your gums. This can then lead to loss of the ligaments that hold the teeth in their sockets.
Periodontal pockets then form (deep openings down beside the tooth). They trap bacteria and can become infected. This causes the gums to shrink away from the teeth, leaving the crown on an unsteady tooth base or vulnerable to decay on the softer tooth root. Regular flossing and gum care is essential to maintain the crown’s success.
Just like a filled tooth, bacteria collecting along the crown margin can cause decay if not cleaned thoroughly and if your diet contains moderate to high amounts of sugar.
Irregular occlusion (bit) can cause discomfort or may make the crown vulnerable to chipping. When the occlusion is misaligned, it creates damage risks to the crowns from uneven pressure. Having your crown’s occlusion checked on a regular basis maintains your optimal biting relationship and does not pose damage risks to the crown from uneven pressure.
It may take a few days to settle in. There may be mild discomfort from the treatment process.
Very few patients have any form of discomfort after a new crown is placed. Most comment that they can’t feel the crown and sometimes they cannot even point out which tooth is the new crown!
We take great care to make sure the tooth pressure is adjusted correctly. If the bite (occlusion) is not meeting properly, the crowned tooth may be under excess pressure when you chew or close your teeth together. This can cause discomfort, pain or aching. The tooth ligaments become stretched and bruised. The constant pressure may cause the pulp of the tooth to become reactive and painful.[/accordion-item]