Periodontal Debridement
World Small Animal Veterinary Association World Congress Proceedings, 2006
Loic Legendre, DVM, FAVD, DAVDC, EVDC
Northwest Veterinary Dental Services, Ltd
North Vancouver, BC, Canada

Periodontitis is by far the main oral pathology encountered, and its universal characteristics are attachment loss, pocket formation, and ultimate tooth loss. Researches show that 80% of dogs over the age of 3 suffer from some form of periodontal disease. It is also the most common disease worldwide, on the human side; periodontal treatment costs totaled $51 billions in North America in 2003, 75% of all dental costs.

The initiating factor is the presence of pellicle. It gives rise to plaque. Plaque, in cats and dogs is comprised of over 700 different bacteria; it is the enemy. With time plaque mineralizes and becomes calculus.

The disease progresses through several stages:

 Stage 1. Marginal gingivitis, where the only sign is the inflammation of the edge of the gingiva; the red line sign.

 Stage 2. Moderate gingivitis. The gingiva is edematous and inflamed.

 Stage 3. Severe gingivitis. The entire gingiva is edematous, it bleeds easily, and periodontal pockets start to form.

 Stage 4. Moderate periodontitis. The inflammation is severe, pockets and pus are present, there is some bone loss and slight mobility.

 Stage 5. Severe periodontitis. There is advanced bone loss, definite tooth mobility, and tooth loss.

 Stage 6. Exfoliation of the tooth. Healed alveolus. Often see atrophy of the dental ledge. Can also see the development of oronasal fistulas.

The first 2 stages represent gingivitis, a condition that is reversible. Once attachment is lost it is almost impossible to regain it. In other word, periodontal disease is irreversible and incurable, only controllable.


The main pathogens in dogs are: Bacteroides sp, Porphyromonas sp., Prevotella sp., Fusobacterium sp., and a few aerobic organisms. In cats the main culprits are: black pigmented Porphyromonas sp., Peptostreptococcus sp., Actinomyces sp.. In cats these species are also found in healthy gingiva.


G-organisms cause rapid tissue destruction, resulting in pocket formation. There is loss of integrity of the sulcular epithelium. Bacteria and their by-products migrate into the periodontal ligament space. The periodontal ligament breaks down and ultimately teeth are lost.

Clinical Signs

Affected patients present with halitosis, ptyalism, face rubbing, nasal discharge, and facial swelling. As the research done by Dr. L. Debowes determined, the signs can also be associated with disease to the organs affected by periodontal disease (heart, kidney, liver, skin, lungs and brain). It has also been shown that periodontal disease interacts with endocrine conditions such as diabetes mellitus, hyperthyroidism and hypothyroidism.

The oral signs of periodontitis are pocket formation and attachment loss. There are three types of pockets listed. Pseudopockets, as the name implies, are not due to attachment loss but rather to gingival hyperplasia creeping up the side of teeth and creating deeper gingival sulci than normal. In suprabony pockets, the bone recedes at the same rate than the periodontal ligament so that the bottom of the pocket is above the bone level. On x-rays, this is seen as horizontal bone loss. In infrabony pockets, the periodontal ligament recedes faster than bone and thus the bottom of the pocket ends up within bone. On x-rays, this is recognized as vertical bone loss.

The consequences of periodontitis are patients with difficulty chewing, chronic periodontal abscesses, bacteremias, weight loss, poor physical condition and pain.


To determine the extent of the disease one should rely not only on visual inspection, but also on palpation, probing and x-rays.

No matter what stage your patient is in, the first treatment step is to perform a complete dental cleaning. Actually, for stage 1 and 2 all that is required is prophylaxis, irrigation and establishment of a good home care program. Stage 3 requires subgingival scaling in addition. For stage 4 subgingival curettage and root planning are needed. Root planning is the removal of infected cementum on the surface of a root. It is performed using a curette. Curettage is the removal of the inflamed connective tissue on the inside of the gingival sulcus. It is also performed using a curette. Both procedures are often indiscriminately referred to as curettage. The two procedures should always be done together and are jointly referred as subgingival scaling.

Subgingival scaling is the simplest of the periodontal procedure and is virtually done at every dental cleaning. Curettes are essential; they need to be very sharp to properly lift the calculus away from the dentin surface. If they are dull, which too often the case, they only burnish the surface of the calculus but do not actually remove it. They also have to be manipulated properly. They are slid into the sulcus with the curvature of the working tip following the curvature of the root. Once at the bottom of the pocket, they are rotated so that their distal shank is parallel to the surface of the root, and they are pulled. They only function in a pull motion. Because one relies on the bends in the shank to reach the desired surface, several curettes are necessary to adequately clean all the root surfaces in the mouth. Subgingival scaling is designed to address pockets 5mm deep or less. Deeper pockets cannot be thoroughly cleaned with scaling alone.

External bevel gingivectomy is a technique designed to deal with moderate gingival hyperplasia or pseudopockets. It is performed by measuring the pocket with a probe, marking the outside of the gingiva with the point of the probe, aligning the scalpel blade at a 45% angle with the surface of the root, and cutting. This should leave a pocket less than 2 mm deep.

It is an easy operation, but its major disadvantage is an important loss of gingiva.

Internal bevel gingivectomy, is a technique where a scalpel is used instead of a curette to perform the curettage of the pocket. It is intended for suprabony pockets, moderate gingival hyperplasia, and to facilitate wound healing. It is a harder procedure than the external bevel gingivectomy, especially in small patients. To accomplish this technique; measure the pocket depth with a probe, mark the gingiva, align the scalpel blade to have it stop on the crestal bone, cut and remove the band of granulating connective tissue with the help of a curette.

In cases where periodontal pockets are deeper than 5mm, more advanced surgical flaps, created with vertical releasing incisions, are also required.

Before performing any periodontal surgery, be sure the client can carry out daily home care. If the client is unable or unwilling to do so, most of your procedures will fail or produce only temporary improvements. Periodontal surgery is performed only after a complete prophylactic cleaning.

Finally, never forget that there is no cure for periodontal disease, only control.

Speaker Information
(click the speaker's name to view other papers and abstracts submitted by this speaker)

Loic Legendre, DVM, FAVD, DAVDC, EVDC
Northwest Veterinary Dental Services Ltd
North Vancouver, British Columbia, Canada

MAIN : Dentistry : Periodontal Debridement
Powered By VIN