Severe Grade 4 periodontal disease
The periodontal tissues are the gingiva, cementum, periodontal ligament, and alveolar supporting bone. More than 85% of dogs and cats older than four years have periodontal pathology.
Periodontal disease starts with the formation of plaque, a transparent adhesive fluid composed of mucin, sloughed epithelial cells, and aerobic, gram positive cocci. Plaque starts forming
twelve hours after dental cleaning. If the plaque is not removed, mineral salts in the food will precipitate to form hard dental calculus. The calculus is irritating to the gingival tissue, changing the ph of the mouth allowing pathogenic aerobic gram negative bacteria to survive subgingivally. By-products of these bacteria "eat away" at the tooth's support structures eventually causing the tooth to be lost
There are two grading systems commonly used to classify the degree of periodontal disease. The mobility index evaluates the looseness of the tooth. With Class I mobility, the tooth only moves slightly. Class II, is when a tooth moves less than the distance of its crown width. Class III mobility moves a distance greater than its crown width. Class III teeth have lost more than 50% of their support, and in most cases should be extracted. Periodontal disease can also be graded from I to IV.
Stages of Periodontal Treatment at the Four Disease Stages
||scaling, root planing, polishing
||deeper edema pockets
||above, plus apical reposition flap surgery
gingival surgery to try to save teeth, or extraction
When periodontal disease is not treated, the subgingival anaerobic bacteria can continue to reproduce, creating deeper periodontal pockets through bone destruction. Eventually, this progression can cause tooth loss and other internal medicine problems.
Imagine a giant tooth sitting in a ten foot garbage can, containing mud and industrial waste. Continue to pretend that it is your job to clean the tooth, and you are only supplied with equipment five feet long. What happens? The top is cleaned and the bottom is allowed to remain in the toxic waste until it eats through the can. How can you solve this problem? Try opening the side of the can to clean the waste out in order to save the tooth. Here is the essence of periodontal surgery.
What decisions do we make when considering periodontal surgery? The correct client, a cooperative patient, a treatable tooth, and choice of which periodontal surgery procedure to use.
The client needs to be committed to save their animal's teeth. This commitment includes daily brushing home care to remove plaque, which begins to colonize within twelve hours after a
professional teeth cleaning. Frequent veterinary dental progress re-examinations and expense should also be considered and discussed prior to periodontal care. The patient must also be a willing partner. If the dog or cat will not allow home care, the best dental surgeon and most caring owner will not make a difference. Unless there is strong owner commitment and patient compliance, it is much wiser to extract
teeth rather than letting the pet suffer.
Choosing appropriate teeth to operate upon is equally important. Every
professional dental teeth cleaning visit should include probing and charting. A periodontal probe is the single most important instrument used to evaluate periodontal health. A probe is marked in millimeter gradations and gently inserted in the space between the gingival margin and tooth. A probe will stop where the gingiva attaches to the tooth or at the apex of the alveolus, if the attachment is gone. Dogs should have less than two millimeter probing depths and cats less than one. Each tooth is probed on a minimum of four sides. Probing depths of all teeth are noted on the dental record, and a treatment plan is mapped out before therapy begins. Pocket depths up to five millimeters can usually be cleaned adequately with curettes. Depths greater than five millimeters need flap surgery or "garbage can side exposure" to evaluate and clean the root surfaces.
Bone loss around root of lower
Intraoral radiography supplies important information when deciding which tooth can benefit from surgery. Radiographs help evaluate the supportive bone mesally (rostral) and distal to the affected tooth. Unfortunately, it is difficult to evaluate the lingual-buccal plane through intraoral films. As a general rule, if there is greater than
50% horizontal or vertical bone loss around a tooth, only heroics may provide long term success. Radiographs should also be examined for other pathology, including endodontic lesions that can be treated prior to and may effect the outcome of periodontal care.
Once we are convinced that surgery will help our patient, the appropriate type of periodontal surgery is chosen. An ideal method allows exposure of the root surface, preserves the attached gingiva, and allows the gingiva to be resutured in a fashion to eliminate the periodontal pocket and promote reattachment to the root surface.
Gingivectomy to remove
excessive gum tissue
At one time, gingivectomy was the treatment of choice to eliminate pocket depth and allow exposure of the root surface for cleaning. Unfortunately, part of the important attached gingiva is sacrificed in the gingivectomy procedure. Gingivectomies should only be used in cases of gingival hyperplasia where there is an overgrowth of tissue. The gingivectomy procedure employs a scalpel or electrosurgical blade
or laser to incise the exuberant gingival tissue at 45 degree angle toward the crown.
Flap surgery is the most appropriate procedure to expose the pathology and render
care in many types of periodontal disease. There are four commonly used methods in small animal dentistry.
|Open Flap Curettage -- 360 degree incisions are made internally into the pockets, angling the blade tip toward the tooth The incision is rarely made past the mucogingival line. A periosteal elevator is used to elevate the flap, exposing the tooth's root surface for cleaning and root planing. Interdental sutures are placed with 4-0 chronic gut on an atraumatic needle|
|Apical Repositioned Flap -- this procedure is used where the clinician wants to decrease the height of the pocket in areas of alveolar bone loss. The blade is inserted 360 degrees around the tooth incising the epithelial attachment. Vertical incisions apical to the mucogingival line are made two to three millimeters mesial and distal to the affected teeth. A periosteal elevator is used to reflect the gingiva exposing the alveolar bone. Sharp projections of the alveolus are smoothed, necrotic debris removed from the root surface, and the area irrigated with chlorhexidine. The horizontally incised gingiva is resutured to the new height of the alveolar bone, thus reducing the pocket depth.|
|Reverse Bevel Flap -- indicated where there are inflamed and necrotic free gingival margins. A portion of the attached gingiva is removed, care must be taken to make sure that enough attached gingiva remains after the procedure. The initial incision is made parallel to the tooth between the diseased and healthy appearing attached gingiva. A half to one millimeter of attached gingiva is left as a collar around the affected tooth. The collar is removed with a sharp curette, the root planed, alveolar defects repaired, and opposing edges of the "healthy" attached gingiva resutured.|
|Canine Palatal Flap -- indicated where there are greater than five millimeter pockets on the palatal or lingual side of the canine teeth. If there is an oro-nasal fistula, as evidenced by sneezing or nasal discharge, then this procedure is not indicated and extraction followed by single or double layer; flap surgical closure of the defect is indicated. Incisions are made to the bone partially extending at a 20 degree angle flare from the affected tooth for four to eight millimeters. A periosteal elevator is used to expose the root for cleaning and the alveolus for application of various bone filling materials in order to decrease the dead space and promote osseous integration. The area is closed with 4-0 chromic gut on an atraumatic needle.|