How a Dental Crown Can Be Securely Attached to a Severely Deteriorated Tooth

Sometimes there isn't enough space to attach a crown, so a dentist must lengthen the crown. A tooth's crown is the visible portion of a tooth, above the gum line. A dental crown is a dental restoration—an artificial shell (typically made of porcelain) that encases the tooth's crown to prevent further deterioration. However, a dental crown can only be bonded to a tooth's crown when there's sufficient tooth structure to permit a secure attachment. So how does a dentist fit a dental crown to a tooth which has already lost a significant portion of its overall structure?

Creating a Secure Bond

A lack of structure (usually when decay has resulted in the loss of the tooth's vertical structure) makes it difficult to achieve a secure bond between a dental crown and the underlying tooth. Although a bond might be possible, it won't be stable enough to guarantee the long-term functionality of your dental restoration. For the necessary amount of stability, your dentist must sometimes lengthen the underlying tooth.

Additional Surface Area

Crown lengthening creates more surface area on a tooth, and this additional surface area creates a more stable foundation for the dental crown. This is simply due to the fact that your dentist now has more space to apply the bonding agent (dental cement). The logic is sound, but how does a dentist lengthen a crown?

The Crown-Lengthening Process

Crown lengthening isn't all that invasive, but since incisions will be made in the soft tissues in your mouth, it can be mildly uncomfortable. You will be given local anaesthesia to numb the site, and additional pain relief will be required in the days to come. Your dentist will make small incisions in the gingival tissues at the base of the tooth, exposing more of the tooth's surface area. Your gums are then sutured in their new position with a sufficient amount of the tooth's surface exposed to permit the attachment of your dental crown.

After the Procedure

The dental crown itself will be attached at a subsequent appointment after your gums have had sufficient time to heal and the swelling has subsided). For the interim period, your dentist will have given you aftercare instructions, but this is standard with oral surgery and involves some dietary restrictions along with being careful to avoid strenuous physical activity. The recovery period is brief, and your new crown can be put in place shortly after the lengthening procedure. 

It's not a foregone conclusion that anyone who needs a dental crown will also need crown lengthening. The procedure simply allows for the restoration of a tooth that has lost some of its structure but has still retained enough structure to hold a dental crown.