Crown Lengthening

There are two situations in which crown lengthening is commonly performed: to improve appearance, and to allow a dentist better access to decay or provide enhanced tooth structure for a dentist to restore a tooth. However there are two main categories of crown lengthening:

  1. Functional Crown Lengthening including Biologic Shaping
  2. Esthetic Crown Enhancement

Functional Crown Lengthening

Functional crown lengthening is often times performed to provide enhanced access at decay which may extend below the gum line. If the dentist is unable to reach decay that is deep under the gum, the tooth could be in jeopardy of being lost. As a rule, simply trimming back the gum is not sufficient, as the underlying bone would be exposed. Rather, the periodontist must expose the bone and modify it in order to allow for access to the decay. The tissue is then replaced with dissolving sutures at a lower position from where it started.

Most crown lengthening procedures are very straightforward, and there is little or no post-operative discomfort. Sutures and any dressing are removed after about 2 weeks. Complete healing, however, generally takes between 8-12 weeks. This time frame allows the tissue to heal at a microscopic level where it is as strong as before the surgery. At this time, we will perform an exit exam/outcome assessment and ensure proper and complete healing has taken place. At that time, any further provisionalization can be performed or the final impressions can be pursued.

When there is a restorative commitment (such as a crown), we generally request that teeth planned for crowns be “provisionalized” (ie. temporary crown) with core build ups prior to surgery. This provides more predictable and accurate surgery and healing to be ensured.

Biologic Shaping

Biologic shaping is an option to the traditional method of crown lengthening which is performed when invasion of the junctional and/or connective tissue attachment associated with a tooth has occurred. Biologic shaping involves reshaping the existing tooth surface in combination with conservative removal of the supporting alveolar bone to create the width needed for the dental restoration to be biologically acceptable.

Biologic shaping accomplishes several goals: 

  1. Minimum supporting bone is removed.
  2. Deleterious root surface anatomy, such as grooves, concavities, and cementoenamel projections, can be diminished or removed completely.
  3. A smooth root surface that is more biologically acceptable to soft tissue is created.
  4. Class I and II furcation lesions (mild to moderately-advanced bone loss between the roots of molar teeth) may be decreased or eliminated improving the long-term prognosis of these compromised teeth.
  5. Improved gingival contours and space for restorative materials can be created in situations where close root proximity between teeth is present. This technique aims to optimize the periodontal health of a tooth to receive a crown and maximize the long-term outcome of the dental restoration for the patient. Scroll down to view two cases where this technique was utilized to enhance the restorative doctor’s outcome in providing a predictable, periodontally healthy, and optimal result long-term for the patient.

Esthetic Crown Enhancement

The part of the tooth that is seen above the gum is called the clinical crown. Sometimes a patient may not have enough of the crown showing above the gums which can lead to the appearance of a “gummy smile” or short, boxy teeth. This often results in an esthetic compromise and a patient who is unhappy with his/her smile. This is a biologic consequence of failure of the tissue and bone complex to migrate to the proper position whereby the full extent of tooth enamel would be exposed. This condition can be managed by manipulating the bone and gingival complex so that the appropriate amount of the tooth is exposed and the biologic parameter are properly in place thereby creating a more natural smile. Esthetic crown enhancement allows for the complete clinical crown to be exposed which allows for better plaque control, a more esthetically pleasing smile and better gingival health.

Below is an example of how the procedure works to enhance the esthetics of a smile.

Click here for case examples on esthetic crown enhancement in our periodontal and surgury case reports.

Please feel free to ask us if there is anything you have questions on: office@periodontalmedicine.org