Periodontal pocket reduction surgery limited to the gingival tissues only and not involving the underlying osseous structures, without the use of flap surgery, can be classified as gingival curettage and gingivectomy. The current understanding of disease etiology and therapy limits the use of both techniques, but their place in surgical therapy is essential.
The word curettage is used in periodontics to mean the scraping of the gingival wall of a periodontal pocket to remove diseased soft tissue. Scaling refers to the removal of deposits from the root surface, whereas planing means smoothing the root to remove infected and necrotic tooth substance. Scaling and root planing may inadvertently include various degrees of curettage. However, they are different procedures with different rationales and indications. Both should be considered separate parts of periodontal treatment.
Curettage in periodontics has been defined as gingival and subgingival curettage (Figure 56-1). Gingival curettage consists of the removal of the inflamed soft tissue lateral to the pocket wall and the junctional epithelium. Subgingival curettage refers to the procedure that is performed apical to the junctional epithelium and that severs the connective tissue attachment down to the osseous crest.
It should also be understood that some degree of curettage is accomplished unintentionally during scaling and root planing and is referred to inadvertent curettage. This chapter refers to the intentional curettage performed during the same visit as scaling and root planing or as a separate procedure to reduce pocket depth by enhancing gingival shrinkage, new connective tissue attachment, or both.
Curettage accomplishes the removal of the chronically inflamed granulation tissue that forms in the lateral wall of the periodontal pocket. This tissue, in addition to the usual components of granulation tissues (i.e., fibroblastic and angioblastic proliferation), contains areas of chronic inflammation, and it may also contain pieces of dislodged calculus and bacterial colonies. The latter may perpetuate the pathologic features of the tissue and hinder healing.
This inflamed granulation tissue is lined by epithelium, and deep strands of epithelium penetrate into the tissue. The presence of this epithelium is construed as a barrier to the attachment of new fibers in the area.
When the root is thoroughly planed, the major source of bacteria disappears, and the pathologic changes in the tissues adjacent to the pocket resolve with no need to eliminate the inflamed granulation tissue by curettage. The existing granulation tissue is slowly resorbed, and the bacteria present in the tissue without replenishment of their numbers from the plaque in the pocket are destroyed by the defense mechanisms of the host. Therefore, the need for curettage to eliminate the inflamed granulation tissue appears to be questionable. (This should not be confused with the elimination of granulation tissue during flap surgery. The reason for the latter is to remove the bleeding tissue that obstructs visualization and prevents the necessary examination of the root surface and the bone morphology. Thus, the removal of granulation tissue during surgery is accomplished for technical rather than biologic reasons.) It has been shown that scaling and root planing with additional curettage do not improve the condition of the periodontal tissues beyond the improvement that results from scaling and root planing alone.
Curettage may also eliminate all or most of the epithelium that lines the pocket wall and the underlying junctional epithelium. Curettage for this purpose is still valid, particularly when an attempt is made for new attachment, as occurs in intrabony pockets. However, opinions differ with regard to whether scaling and curettage consistently remove the pocket lining and the junctional epithelium. Some investigators report that scaling and root planing tear the epithelial lining of the pocket without removing either it or the junctional epithelium.33 Others claim that both epithelial structures6,7,32 and sometimes the underlying inflamed connective tissue34 are removed by curettage. Some investigators have reported that the removal of the pocket lining and the junctional epithelium by curettage is not complete.51,54,57
An awareness of aesthetics in periodontal therapy has become an integral part of care in the modern practice of periodontics. In the past, pocket elimination was the primary goal of therapy, and little regard was given to the aesthetic result. Rapid shrinkage of the gingival tissue was the goal to eliminate the pocket. Currently, aesthetics is a major consideration of therapy, especially in the maxillary anterior area (teeth #6 through #11), and every effort is made to minimize gingival tissue shrinkage and to preserve the interdental papilla.
Compromise therapy is feasible in the anterior maxilla. This therapy consists of thorough subgingival root planing while attempting to not detach the connective tissue attachment beneath the junctional epithelium. Gingival curettage should be avoided. The granulation tissue in the lateral wall of the pocket, in an environment that is free of plaque and calculus, becomes connective tissue, thereby minimizing gingival shrinkage. Thus, although complete pocket elimination is not accomplished, the inflammatory changes are reduced or eliminated, and the interdental papilla and the aesthetic appearance of the area are preserved.
There are many instances in which a surgical flap is necessary for access to the root surface for scaling and root planing. A surgical technique that has been specially designed to minimize gingival recession and preserve the interdental papilla is the papilla preservation technique (see Chapter 59).
Another important precaution is to avoid root planing apical to the base of the pocket to the osseous crest. The removal of the junctional epithelium and the disruption of the connective tissue attachment exposes the nondiseased portion of the cementum. Root planing and the removal of the nondiseased cementum may result in excessive shrinkage of the gingiva, which results in increased gingival recession.
2. Curettage can be attempted as a nondefinitive procedure to reduce inflammation when aggressive surgical techniques (e.g., flaps) are contraindicated in patients as a result of their age, systemic problems, psychologic problems, or other factors. It should be understood that, in these patients, the goal of pocket elimination is compromised, and their prognosis is impaired. The clinician should attempt this approach only when the indicated surgical techniques cannot be performed and both the clinician and the patient have a clear understanding of its limitations.
3. Curettage is also frequently performed on recall visits45 as a method of maintenance treatment for areas of recurrent inflammation and pocket depth, especially where pocket reduction surgery has previously been performed. Careful probing should establish the extent of the required root planing and curettage.
Curettage does not eliminate the causes of inflammation (i.e., bacterial plaque and deposits). Therefore, curettage should always be preceded by scaling and root planing, which is the basic periodontal therapy procedure (see Chapter 46). The use of local infiltrative anesthesia for scaling and root planing is optional. However, gingival curettage will always require some type of local anesthesia.
The curette is selected so that the cutting edge is against the tissue (e.g., Gracey no. 13 or 14 for mesial surfaces, Gracey no. 11 or 12 for distal surfaces). Curettage can also be performed with a 4R-4L Columbia Universal curette. The instrument is inserted to engage the inner lining of the pocket wall, and it is then carried along the soft tissue, usually in a horizontal stroke (Figure 56-2). The pocket wall may be supported by gentle finger pressure on the external surface. The curette is then placed under the cut edge of the junctional epithelium to undermine it.
During subgingival curettage, the tissues attached between the bottom of the pocket and the alveolar crest are removed with a scooping motion of the curette to the tooth surface (Figure 56-3). The area is flushed to remove debris, and the tissue is partly adapted to the tooth by gentle finger pressure. In some cases, the suturing of separated papillae and the application of a periodontal pack may be indicated.
The excisional new attachment procedure has been developed and used by the US Naval Dental Corps.40,62,63 It is a definitive subgingival curettage procedure that is performed with a knife. The excisional new attachment procedure technique is as follows:
1. After adequate anesthesia, make an internal bevel incision from the margin of the patient’s free gingiva apically to a point below the bottom of the pocket (Figure 56-4). Carry the incision interproximally on both the facial and the lingual side, and attempt to retain as much interproximal tissue as possible. The intention is to cut the inner portion of the soft-tissue wall of the pocket all around the tooth.
2. Remove the excised tissue with a curette, and carefully perform root planing on all exposed cementum to achieve a smooth, hard consistency. Preserve all connective tissue fibers that remain attached to the root surface.
The use of ultrasonic devices has been recommended for gingival curettage.35 When applied to the gingiva of experimental animals, ultrasonic vibrations disrupt tissue continuity, lift off the epithelium, dismember collagen bundles, and alter the morphologic features of fibroblast nuclei.20 Ultrasound is effective for debriding the epithelial lining of periodontal pockets. This results in a narrow band of necrotic tissue (microcauterization), which strips off the inner lining of the pocket.
The Morse scaler-shaped and rod-shaped ultrasonic instruments are used for this purpose. Some investigators found ultrasonic instruments to be as effective as manual instruments for curettage35,50,64 and that such tools resulted in less inflammation and less removal of underlying connective tissue. The gingiva can be made more rigid for ultrasonic curettage by injecting anesthetic solution directly into it.10
Since early in the development of periodontal procedures,53,61 the use of caustic drugs has been recommended to induce a chemical curettage of the lateral wall of the pocket or even the selective elimination of the epithelium. Drugs such as sodium sulfide, alkaline sodium hypochlorite solution (Antiformin),8,24,26 and phenol4,9 have been proposed and then discarded after studies indicated their ineffectiveness.5,18,26 The extent of tissue destruction with these drugs cannot be controlled, and they may increase rather than reduce the amount of tissue to be removed by enzymes and phagocytes.
Immediately after curettage, a blood clot fills the pocket area, which is totally or partially devoid of epithelial lining. Hemorrhage is also present in the tissues with dilated capillaries and abundant polymorphonuclear leukocytes, which appear on the wound surface. This is followed by a rapid proliferation of granulation tissue with a decrease in the number of small blood vessels as the tissue matures.
The restoration and epithelialization of the sulcus generally require 2 to 7 days,27,34,37,57 and restoration of the junctional epithelium occurs in animals as early as 5 days after treatment. Immature collagen fibers appear within 21 days. Healthy gingival fibers that are inadvertently severed from the tooth and tears in the epithelium are repaired during the healing process.33,46 Several investigators hav/>