Learning Objective

An introduction to periodontal surgery presenting techniques which may be performed by appropriately equipped and educated general practitioners. They should be able to introduce these procedures into daily practice after an additional practical workshop.

The gingival sulcus is the area between the inner surface of the free gingiva and the tooth. Its depth is 0–3 mm in a dog and 0–0,5 mm in a cat.¹ Periodontal pockets are present in many small animal patients, especially older small and toy breed dogs. Any pocket which has a depth greater than is normal for the species is pathological and in need of therapy.

In dogs, pockets between 3 and 5 mm (and possibly up to 6 mm), which are not associated with tooth mobility or other pathology (furcation, root caries), are best treated with scaling/root planing. Pockets deeper than 5 mm and/or those associated with other pathology (especially furcation level II and III exposure) cannot be effectively cleaned without direct root visualization.²

Any dental procedure starts with a complete dental prophylaxis to decrease oral contamination. Then, a complete oral exam is performed. This should include a visual assessment and periodontal probing. Finally, dental radiographs should be taken of the surgical area to document attachment levels.

Periodontal surgery is a part of periodontal therapy and is focused on removing deposits and diseased tissue and regaining attachment with preservation of at least 2 mm of attached gingiva.³ However, without a commitment to consistent homecare and regular rechecks, such surgery will ultimately fail. This should be communicated to the client prior to performing surgery. Most periodontal therapy occurs in older patients and therefore thorough assessment prior to anaesthesia as well as adequate pain management is mandatory.

There are two major methods available for treating minor periodontal pockets: cleaning by hand, which is performed with a curette; and mechanical cleaning, typically performed with an ultrasonic device. The first, known as scaling/root planing is the most commonly used technique in both human and veterinary periodontology. It is highly effective for plaque and calculus removal, as well as removing granulation tissue, which in turn reduces pocket depth and controls infection. The second, mechanical therapy requires access to special tips, which can be used subgingivally. These tips are finer and have a coolant spray directed near the tip of the instrument. When properly performed, ultrasonic debridement may be less traumatic than hand scaling and reduce the duration of anaesthesia.

Equipment

All incisions for periodontal surgery are best accomplished with a number 15 or 11 scalpel blade. Other equipment should include a selection of periodontal elevators, several sharp curettes, 7 x 7 tissue forceps, tissue scissors, suture scissors and small needle holders. Suture material should be swaged on a reverse cutting needle and should be fine and absorbable: 5-0 in most patients or 4-0 in the largest individuals. In cases where bone augmentation is desired/indicated, materials for guided tissue regeneration are necessary. This should include at least an absorbable barrier membrane and bone grafting/augmentation products.

Gingivectomy/Gingivoplasty

These two techniques are usually performed together and they aim to reshape the gingiva to create a physiological state and reestablish the normal depth of the gingival sulcus. There are different techniques available using cold steel, diamond burrs, electro surgery or lasers. Initially, the incision line has to be calculated to achieve a new free gingival margin approximately 1–2 mm coronally to the cemento-enamel junction. As plaque may interfere with wound healing, a careful but disciplined home care must be recommended and tooth brushing should start as early as 14 days postsurgery. Application of oral cleansing gel 2–4 times a day seems to be the best solution for the recovery period.⁴

Periodontal Flaps

Periodontal flaps are required to visualise affected roots, manage effective cleaning, reshape affected tissue and cover damaged surfaces. The most common flap used in periodontal surgery is a full flap with vertical releasing incisions. This allows increased exposure but is somewhat more invasive. The other common flap for periodontal surgery is the envelope flap. This is created along the arcade, without vertical incisions.

Making a flap starts with an incision at the sulcus which creates a reverse bevel. This means that the blade is angled away from the tooth at approximately a 45-degree angle. This is designed to remove the diseased pocket epithelium. Once the reverse bevel incision is performed, the rest of the flap is created.

Envelope Flap

The advantage of this flap is that there is less chance of dehiscence and less suturing than for a full flap. The only disadvantage is that there may not be as much exposure for cleaning the surface of the root. The incision should be made in one motion all the way down to the alveolar bone. This will create a full thickness flap. The incision can be carried to adjacent healthy teeth, if necessary for sufficient exposure.

After the extent of the horizontal flap is created, the flap is elevated from the alveolar bone. This is best performed with a sharp periosteal elevator. Carefully release the full thickness flap to expose the root surface and alveolar bone for cleaning and contouring. After the procedure, the flap is replaced and sutured interdentally in a tension-free manner.

Full Flaps

This procedure is initiated using a reverse bevel incision around the target tooth (teeth). Once accomplished, one vertical releasing incision (triangle flap) or two incisions (trapezoid flap) are created mesial and distal to the exposed area. These incisions should be made very slightly divergent so that the base of the flap is slightly wider. This is important to maintain blood supply. Additionally, the incisions are typically made on line angles of the target teeth. Line angles are theoretical lines where the two edges of a tooth meet. Incisions should never be made mid root as this will damage the periodontal attachment.

After the extent of the flap is created, it is elevated from the alveolar bone using a sharp periosteal elevator. After the procedure, the flap is replaced and sutured in a tension-free manner. The vertical incisions are closed with simple interrupted sutures placed 2–3 mm apart.⁵

Treating the Exposed Root/Bone Surface

Making a flap allows visualisation of the root surface and creation of a smooth and clean tooth surface for reattachment. Initially, this is performed by root planing using both ultrasonic and hand scaling. Then a sharp curette is used to plane the exposed root surface as smooth as possible.

Following the root planing, the remaining alveolar bone is smoothed to produce a knife sharp edge. Additionally, the bone should be scalloped around the tooth. This can be performed with a bone chisel or a finishing burr. Then, root conditioning is performed. This step is designed to clean the root surface as well as to slightly demineralize it to improve reattachment. Classically it was performed with citric acid but EDTA has also been described as a good product. Finally, the conditioner is rinsed from the surface. If bone augmentation is indicated, the material is mixed according to manufacturer's directions and placed in the defect. There are numerous products available and the practitioner must make their own decision based on cost. A barrier membrane should be placed over the surgical site, if bone regrowth is desired. In veterinary medicine, absorbable membranes should be used.^6,7

References

1.  The complete dental cleaning. In: Niemiec BA, eds. Veterinary Periodontology. Wiley and Sons; 2013:129–153.

2.  Advanced nonsurgical therapy. In: Niemiec BA, eds. Veterinary Periodontology. Wiley and Sons; 2013:154–169.

3.  Wiggs B. Periodontology in Veterinary Dentistry Principles and Practice. Lippincott-Raven; 1997:186–231.

4.  Gorrel CE, Hale FA. Gingivectomy and gingivoplasty. In: Verstreate FJM, Lommer MJ, eds. Oral and Maxillofacial Surgery in Dogs and Cats. Saunders; 2012:167–174.

5.  Periodontal flap surgery. In: Niemiec BA, eds. Veterinary Periodontology. Wiley and Sons; 2013:206–248.

6.  Gingerich W, Stepaniuk K. Guided tissue regeneration for infrabony pocket treatment. J Vet Dent. 2011;282–288.

7.  Treatment of the exposed root surface. In: Niemiec BA, eds. Veterinary Periodontology. Wiley and Sons; 2013:249–253.