Jan Bellows, DVM
Diplomate, American Veterinary Dental College
All Pets Dental Clinic
9111 Taft St.
Pembroke Pines, Fl. 33024
(954) 432-1111
PERIODONTICS
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 two to five days 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 it's crown width. Class III mobility
move 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 V.
Stages of Periodontal Treatment at the Five
Disease Stages
1 normal~coral pink 1.home care
2.edema 2 polishing
3 edema-pockets 3.scaling, root planing,polishing
4.edema-pockets deeper 4`above plus possible
beginning bone loss apical reposition flap surgery
5 more advanced 5` above plus possible
with tooth mobility osteoplasty, flaps, and splinting
PERIODONTAL DISEASE
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 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 should the veterinarian 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 prophy procedure. 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 the tooth rather than letting the pet suffer.
Choosing appropriate teeth to operate upon is equally important. Every dental
prophylaxis 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.
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 75% 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 the clinician is convinced that he or she is working on the right
patient and tooth, the appropriate type of periodontal surgery is chosen. an
ideal method allows exposure of the root surface, preserves the attached
gingiva, and to allow the gingiva to be resutured in a fashion to eliminate
the periodontal pocket and promote reattachment to the root surface
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 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. 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- 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 n~crotic 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 mode 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
layere; 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.