A dental crown is a tooth shaped ‘cap’ that is placed on top of a tooth which restores the tooth to it’s original anatomy.
The purpose of a dental crown is to reinforce the tooth which may be fragile following a root canal therapy or to protect a tooth from further cracks. Cracks are common in teeth that have previously been restored using an amalgam filling in the past. Dental crowns may also be used to repair a decayed tooth that has lost a lot of it’s original tooth structure.
A dental crown is usually done over two appointments, in the first appointment the dentist will remove approximately 1mm of the outer layer of your tooth and take a mould of your mouth so it can be sent to a lab to be made, if the crown is being made a front tooth, the dentist may also take some photos so the crown can be painted/stained to look as similar as possible to your adjacent teeth. The crown will be the same thickness as the layer removed so it will sit flush with your natural tooth. Most materials can be designed to look like your natural tooth colour, however, if a the crown is made of gold the colour cannot be changed.
The dentist will place a temporary crown on which will prevent the tooth from becoming sensitive to hot and cold, it will also stop the tooth from moving while the crown is being made by the technician as teeth can move quite quickly and it may be difficult to seat the crown correctly if this tooth erupts and further or the teeth on either side drift slightly.
Once the crown comes back from the lab, the dentist will remove the temporary crown and cement the permanent crown on.
Dental crowns can last for many years if they’re cared for properly, although a crown is made from an artificial material and cannot decay, the tooth which supports the crown can still decay so this tooth should be brushed and flossed like any other to reduce any risk of decay or inflammation of the gum surrounding this tooth. If a tooth that has a crown becomes decayed, the crown may need to be removed in order to remove the decayed and replaced with a new crown. Regular dental check-ups and diagnostic x-rays can reduce this risk as the dentist/dental hygienist can see areas where calculus is building up below the gum line and areas that have started to decay but may still be reversed before a filling is required.
A dental bridge is a form of tooth replacement that involves a crown on the tooth either side of a space which supports a false tooth that fills the gap between these teeth. A dental bridge can be used to fill a space where one or more teeth have been removed, it is a fixed alternative to a denture. Dental bridges are a great fixed option, especially if your adjacent teeth will benefit from being reinforced by crowns.
The preparation for a dental bridge is very similar to that of a dental crown, the main difference is that 2 teeth are ‘prepared’ for a crown in the same appointment therefore the appointment would be longer. Once the teeth have been prepared, the dentist would take a mould of your teeth and place a temporary crown/bridge on the teeth that have been prepared. If the bridge is being made a front tooth, the dentist may also take some photos so the bridge can be painted/stained to look as similar as possible to your adjacent teeth. For a front tooth, the dentist may also be able to place a temporary bridge using a soft material to fill the gap and improve the aesthetics while waiting for the permanent crown to come back from the lab. For a back tooth, the dentist would generally place 2 temporary crowns on the teeth that have been prepared and the space would remain empty until the permanent bridge is cemented on.
A dental crown is also used as part of the restoration phase of a dental implant, in this case there is a screw place through the center of the crown which secures it to the titanium implant. For more information on dental implants please click here.