Gum Recession

In health, there are two types of gum tissues that surround the tooth. The part that is around the neck of the tooth is firmly attached to the tooth and underlying bone, and is called attached gingiva. The attached gingiva is immovable and tough, and deflects food as it hits the gum. Below the attached gingiva is looser gum, or alveolar mucosa. This tissue contains muscle, and is flexible to allow movement of the cheeks and lips. The muscles in the alveolar mucosa are constantly contracting, which pulls on the bottom edge of the attached gingiva. However, normally the attached gingiva is wide and strong enough to act as a barrier, which prevents the gum from being pulled down (receding).

Some people are born without sufficient attached gingiva to prevent the muscle in the alveolar mucosa from pulling the gum down. In these cases the gum slowly continues to recede over time, even though the patient may be very conscientious with their oral health. This is not an infection, as is seen with periodontal disease, but rather simply an anatomic condition. Unfortunately, bone recession is occurring at the same time the gum is receding. This is because the bone, which is just under the gum, will not allow itself to become exposed to the oral cavity and moves down with the gum.

A lack of attached gingiva is sometimes associated with a high frenum attachment, which exaggerates the pull on the gum margin. A frenum is a naturally occurring muscle attachment, normally seen between the front teeth (either upper or lower). It is normal to have a frenum, but it should not pull on the gum margin or recession will occur. If pulling is seen, the frenum is surgically released from the gum with a frenectomy. Often a new band of hard gum is also added to re-establish an adequate amount of attached gingiva (see below).

With the wear and tear of time, even normal attached gum can be worn away, generally from vigorous brushing. This often happens in people with naturally thin tissues, or when the tissues have been stretched during orthodontics. If there is still adequate attached gum to act as a barrier to the muscle, the treatment for recession is to ensure further damage isn't done when brushing. However, if the attached gum is worn to the point where it cannot resist the constant pull of the mucosa, recession will continue unless a new hard band of gum is placed. Unchecked, the recession can cause tooth loss as the bone recedes with the tissue and tooth support weakens.

The replacement of missing attached gum is called gingival grafting. The muscle that is pulling down on the edge of the gum is first surgically resected and repositioned away from the gum margin. Then a small piece of attached gingiva is taken from an available source, often the roof of the mouth, and transplanted to the site in question. The new tissue reattaches and reforms a new layer of attached gum, which should last a lifetime with proper care. The donor source heals quickly, just like a skinned knee might. With this procedure the root is not covered, and the tissue stays at the same level as before, except with attached gingiva at the margin. These procedures are very easy on the patient, and rarely require more than over-the-counter pain prevention pills post-operatively (ibuprofen). The most difficult part of the surgery is not chewing on the area for 2 weeks. (See Free Gingival Graft-Clinical Case)

Routine gum grafts ("free gingival grafts") do not cover up the exposed root surface - if this is desired, a different technique is used (See Cosmetic Procedures, Root Coverage). Covering the root also makes the tooth stronger, for the bone, which actually holds the tooth in place, and will not change regardless of the new gum level. However, root coverage procedures are primarily done for cosmetic reasons when there is root sensitivity after recession, when there is decay on the root surface or when an old gum line filling needs replacement.

Free Gingival Graft - Clinical Case

The free gingival graft is used when more attached (hard) gingiva must be added around the neck of a tooth. If there is inadequate attached gingiva, spontaneous recession of the gum and bone will occur over time. Typically the normal attached gingiva has been worn away with improper brushing, although some people are born with very little attached gingiva. When a new band of attached gingiva is created with a free gingival graft, the site is stable and, with proper brushing techniques, the results can be expected to last a lifetime. It should be remembered that free gingival grafting is normally not done to re-cover the exposed root. If that is desired, a connective tissue graft is the common procedure used. (See Cosmetic Procedures/Root Coverage)

The first step in grafting is to dissect away the muscle (mucosa) where more attached gingiva is needed. In this case there is a small band of attached gingiva left, but it is not strong enough to prevent the muscle pull from causing recession. The muscle is sutured down away from the tooth, leaving only bone and periosteum (a thin layer of tissue that covers the bone) exposed. The periosteum will supply the graft with blood during healing.

The tissue in the roof of the mouth (palate) is composed of dense connective tissue, similar to attached gingiva. A thin layer is removed from near the teeth, and is transplanted to the site needing attached gingiva. The palate looks similar to a skinned knee when the graft is taken. It is generally covered with a periodontal dressing, and heals very quickly. In several weeks, it will not be possible to detect the donor site.

When the graft is removed, it is trimmed to fit the "bed", and secured in place. It is common to glue the graft into position with medical "super glue", or it may be sutured. A periodontal dressing is usually placed to cover and protect the graft. The patient must stay away from the area for 10-14 days, at which time the dressing is removed. Postoperative discomfort is usually minimal, and the success rate near 100%.

Click here for more information on gum recession from the American Academy of Periodontology.