Basic Periodontal Flaps
Robert Wiggs United States
With the large number of patients requiring periodontal therapy, some will need periodontal surgical intervention to various degrees. Most often, these treatments will be in the form of gingivoplasties, various flaps, and in some special cases, guided tissue regeneration. The goals of periodontal therapy involve removing calculus or diseased tissue and minimizing pocket depth while preserving at least 2 mm of attached gingiva to protect alveolar bone and mucosa from eroding.
If root surfaces are exposed or if the pocket depth is less than five mm, closed root planing and subgingival curettage may be performed. Using a curette subgingivally with overlapping strokes in horizontal, vertical, and oblique directions, root planing removes calculus, debris, and necrotic cementum to provide a clean, smooth surface. The curette can also be angled slightly to engage the gingival surface for removal of diseased or microorganism-infiltrated tissues. When pocket depth exceeds 5 mm, or other pathology exists, more invasive procedures are warranted.
Occasionally, significant local or generalized increases in pocket depths without attachment loss will occur with conditions such as gingival hyperplasia or associated with an epulis. In these cases, gingivectomy removes redundant gingiva to reduce the suprabony pseudopocket depths to facilitate the cleaning of tooth surfaces while maintaining at least 2 mm of attached gingiva. Pocket depth is measured and a corresponding bleeding point is made with the probe at several junctures around the affected teeth. A beveled incision is made with a scalpel blade connecting the bleeding points, maintaining a scalloped edge gingival appearance and preserving adequate tissue.
When pocket depths exceed 4 mm but with minimal bone loss or diseased soft tissue that needs removal, a simple flap allows access and improved visibility for open curettage and root planing. Inserting the scalpel blade into the sulcus and following the scalloped contour severs the epithelial attachment. For large areas requiring treatment, vertical-releasing incisions can be made at the mesial and distal ends of the initial incision. Using a periosteal elevator, the gingiva is reflected to expose the root surfaces. A polishing of the root surfaces and irrigation with dilute chlorhexidine follows thorough root planing and subgingival curettage. After repositioning the flap, it is sutured interdentally with absorbable, interrupted sutures. While this procedure is most commonly performed on facial and lingual surfaces, deep pockets on the palatal aspect of the maxillary cuspid teeth can be exposed using a similar technique for treatment.
When the pockets are greater than 4 mm with bone loss and significant amounts of compromised pocket epithelium, a reverse bevel flap is employed to remove the affected gingiva and provide access for thorough cleaning, as long as sufficient attached gingiva is present. With the scalpel blade angled to the alveolar bone, the incision is made into the gingiva leaving a thin collar of marginal tissue. The flap is elevated (sometimes exposing the alveolar crest) if osteoplasty is warranted. The collar of diseased tissue is removed with a curette and the root surfaces are completely cleaned, polished, and irrigated. Interdental sutures help reposition the gingiva.
For more involved lesions of deep intrabony pockets greater than 5–6 mm with bone loss and minimal attached gingiva, open curettage with an apically repositioned flap is desired. As in the simple flap technique, similar incisions are made at the epithelial attachment and for vertical release, allowing sufficient exposure to provide for the root planing and curettage. Often bone margins are sharp, irregular, or necrotic, and require remodeling. The main goal is to reposition the gingiva so it overlies the alveolar bone with the margin extending 2 mm coronally. This margin should not lie apical to adjacent mucogingival lines, however.
Other periodontal procedures may involve pedicle or free gingival grafts to insure that at least 2 mm of attached gingiva is present at a particular site. Bone defect management and guided tissue regeneration strive to return the periodontal structures to a more normal state, and periodontal splinting allows stabilization of loose teeth to encourage reattachment.
Guided tissue regeneration (GTR) in dentistry normally deals with the reestablishment and regeneration of periodontal tissues lost due to disease or injury. Tissue regeneration has been demonstrated with alveolar bone, cementum, and the periodontal ligament in specific situation with specific types of therapy.
Research has supported the theory that the category of periodontal reaction and attachment being dependent upon the type of tissue that first repopulates the root surface. Based upon this theorem, there are basically four tissues that can repopulate the root surface, each resulting in various periodontal effects. These tissues are gingival epithelium, gingival connective tissue, alveolar bone, and periodontal ligament. In this theory, each cellular type of the above results in a different attachment consequence. Gingival epithelial cells, which migrate along the gingival connective tissues down to the root surface, result in long junctional epithelial attachments. If gingival connective tissue is first to repopulate the root surface, then root resorption usually occurs. Should the cells to repopulate originate from bone then one of two repercussions occurs, either root resorption or ankylosis. But when periodontal cells are the first to repopulate the root surface, new attachment results. The periodontal cells have the ability to redevelop cementum on the root surface and a healthy attachment may be generated.
The fundamentals are to place a physical barrier between the instrumented root surface and the gingival flap. The barrier acts as a deterrent to exclude the gingival epithelium or gingival connective tissue from populating the root structure. This barrier then provides an area for the progenitor cells of the periodontal ligament and/or alveolar bone to have free access for migration. As the soft tissues of the periodontal ligament develop faster than bone, it is hoped that this migration and growth happens prior to bony incursion. It is generally believed that periodontal cells have the greatest potential to promote new attachment but that bone also plays a significant role. Studies have suggested that GTR barriers should be in place and intact for 28 to 42 days for desired effect.
Post operatively vigorous home care and plaque control is essential. Antibiotics for up to three weeks post-surgery are generally recommended.
Home care is one area in which the entire staff can play an important role. Client education about the proper methods and materials for dental hygiene is crucial to the process. Staff members should be well versed in available home care products and techniques so they can aid in demonstrations for the pet owner. Client education can start at a very early stage by introducing new puppy and kitten owners to the concept of brushing as part of a regular grooming and hygiene program. Some pets may be difficult to treat and the risk of injury to the owner should be assessed in recommending home care.
Even though hard crunchy objects provide chewing exercise that can help reduce plaque and calculus accumulation, care should be taken with certain objects. Hard crunchy food and treats definitely have benefits but some of the harder chew toys can possibly cause some damage. Real bones, rocks, and even ice should always be avoided.
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