A crown is a cap placed over a tooth and held in place by dental adhesive or cement. Crowns are fabricated in the laboratory using a variety of different materials including plastic, ceramic, metal alloys or zirconia. These materials make it possible to maximise strength and simulate the appearance and colour of natural teeth.

Crowns are used for several reasons:

• As a protective cover for badly decayed or fractured teeth
• As a permanent restoration for teeth with large fillings
• To correct minor problems in natural teeth (e.g. spacing, irregular shape, discolouration)

At the first appointment, the dentist conducts a thorough clinical examination using radiographs. The suitability for crowns is assessed and any preparatory work is carried out.

Your dentist will also be able to advice on material choices, treatment sequence and any other concerns you may have.

At the second appointment, the teeth to be crowned are prepared. This involves reduction of the tooth size (usually under local anaesthesia) followed by an impression or mould of the prepared tooth.

This trimming of the tooth is required to create space for the crown to be fitted.

The mould is then sent to a laboratory where skilled technicians will fabricate the crown. Meanwhile, a temporary crown is made and fitted onto the trimmed tooth.

At the third appointment, the temporary crown is removed and the tooth surfaces cleaned. The completed crown is put on for fit, harmony with the bite and appearance. The crown is finally cemented onto the prepared tooth with dental cement.

Daily brushing and flossing are essential for good oral health.

Crowns – Treatment Outcomes 

A study[1] done in 2020 evaluated the survival and success rates of crowns placed in patients who had root canal treatment done on premolars at NDCS. These were teeth that were badly broken down and needed an additional foundation in order to be retained. Patients were examined 7 years after crown placement.

Out of 329 teeth examined, 25 teeth were lost and 40 crowns had failed with complications requiring the tooth to be extracted. 88.6% of these teeth were still in function after 7 years but some had complications not requiring an extraction. Common complications observed include recurrent gum disease, caries, porcelain chipping, and tooth fracture.

75.1% of these compromised teeth remained intact and maintained the same condition as when they were first placed with no complications.

While tooth loss, crown failure and complications may be expected in the long term for badly broken down teeth, crown placement is still a viable treatment to help to extend the time the tooth can be kept.

[1] Phang ZY, Quek SHQ, Teoh KH, Tan KBC, Tan K. A Retrospective Study on the Success, Survival, and Incidence of Complications of Post-Retained Restorations in Premolars Supporting Fixed Dental Prostheses with a Mean of 7 Years in Function. Int J Prosthodont. 2020 Mar/Apr;33(2):176-183. doi: 10.11607/ijp.6090. PMID: 32069342.