THE PRAGMATIC APPROACH TO PERIODONTAL THERAPY
Under most circumstances, human periodontal therapy starts with scaling, root planing and polishing, followed by a several week interval to permit healing and reattachment to occur. This often significantly reduces pocket depth and reduces the acute inflammatory response in tissues that may be surgically manipulated subsequently. The result is that it may avoid the necessity for involved procedures such as flap surgery or bone augmentation. Since human patients are not given general anesthesia for periodontal procedures, there is little or no risk to staging periodontal procedures, and considerable advantage. Under most circumstances, veterinarians will continue to perform most periodontal treatments as single procedures, much as we routinely perform root canal procedures in dogs in a single treatment session, compared to 3-4 ‘visits’ for human endodontic treatment. This inevitably involves some compromise: a clear understanding of the owner’s desires and likely abilities to manage home care long term will avoid some troublesome misunderstandings with the owner and unsatisfactory care for the animal. In an old or systemically sick dog, compared to a healthy, younger dog, the specific treatment decision is shifted more readily to extraction, to reduce the need for additional anesthesias subsequently. In a severely medically compromised animal that is a very poor anesthetic risk, long term or intermittent antibiotic therapy (see Prophylaxis section) may be the only practical treatment for severe periodontal disease.
PROPHYLAXIS – TEETH SCALING
Prophylaxis consists of inspection and charting of the teeth, supra and subgingival scaling, root planing, polishing, irrigation, home care instruction (and extraction as indicated). Performed completely in a dog with extensive periodontitis, it can require 2-3 hours of professional working time under anesthesia, and is rarely completed in less than 30 minutes even in an animal with minimal disease. It is a prophylactic procedure, in that it removes the periodontal disease-causing plaque and calculus.
RESULTS FOLLOWING CONSERVATIVE PERIODONTAL THERAPY
There are several studies that examine the effectiveness of scaling and plaque removal in dogs. When plaque removal is performed mechanically very thoroughly daily or every other day, the periodontal tissues stay in a clinically healthy condition for the duration of treatment, as shown in a four year study in dogs. Chemical plaque removal can produce similar results, though gradual accumulation of calculus is inevitable. An abrasive diet slows accumulation of plaque and calculus. The two factors that determine long-term results in dogs are the extent of disease existing prior to treatment (eg., presence or absence of furcation involvement that promotes plaque retention in areas that are very difficult for the owner or dog to clean on a frequent basis), and the efficacy of long-term plaque retardation. Few owners are scrupulously conscientious, and thus there is a broad range of clinical effectiveness. Home care is the key!
Antibiotic treatment is not necessary as a routine when cleaning the teeth of dogs and cats, as the inevitable bacteremia is cleared within about 30 minutes. Animals with immune-suppressive diseases or those under treatment with immune-suppressive medications, and those with clinical evidence of cardiac disease where there may be a risk of development of bacterial endocarditis, can be given a single dose of an antibiotic at the time of induction of anesthesia. Antibiotic treatment should be commenced before surgery and continued for 4-5 days subsequently in animals in which teeth cleaning and a sterile surgical procedure elsewhere in the body are combined. Antibiotic therapy does extend the response period following scaling if no home care is provided, though antibiotic therapy has no measurable long term effect if home oral care is thorough and consistent.
The most important aspect is compliance of owner and animal with a continuing program designed to retard plaque and calculus formation. The most practical way for most owners is to have the animal do the work. A natural diet for carnivores requires the animal to tear food material, which has a natural flossing action. Chewing materials that mimic a natural diet are rawhide (collagen) strips. Large hard biscuits, and nylon and similar toys are also somewhat beneficial. The Heinz Tartar Check and Nabisco T/C Milkbone treats contain a chemical anti- calculus agent. Dry food fed dry may result in less plaque accumulation than canned food. Hill’s Prescription Diet t/d is more effective than a ‘standard’ dry dog food, and can be used as a long- term maintenance diet.
Daily brushing is ideal. Chlorhexidene has proven to be effective, and is available to veterinarians as a palatable oral solution (Nolvadent, Fort Dodge) and gel (CHX, VRx Products). Another palatable plaque retardant is CET dentifrice (VRx Products). Demonstrate to the owner how important you regard follow-up care at home by taking time in the office to demonstrate good application technique.
As for the human mouth, regular (6 months, preferably) re-evaluation is essential for ensuring maintenance of healthy teeth and periodontium.
CLINICAL INDICATIONS FOR ANTIBIOTIC THERAPY IN ORAL DISEASE:
1. Oral ulceration is severe and causing sufficient pain so that the animal is not willing or able to drink, but where scaling is indicated as part of the therapeutic plan. Examples are cats with gingivitis-stomatitis, or dogs with ulcerative stomatitis. A 5-7 day course of clavamox, clindamycin or metronidazole will lessen the inflammation and encourage a rapid return to eating following the scaling procedure. The likelihood of establishing an effective home care plaque control regime with brushing also is much greater if the tissues are less inflamed and the animal therefore more cooperative when the brushing is started.
2. A dog with severe periodontitis, but where the owner wishes to retain as much of the dentition as possible. A two-stage periodontal procedure is performed. The sequence is pre-treatment for 5 days with clavamox, clindamycin, spiramycin-metronidazole or metronidazole alone, followed by scaling under anesthesia, and continuation of the antibiotic administration and oral rinsing with chlorhexidine for 10-14 days. Then the animal is re-anaesthetized for the definitive periodontal procedure (ie.. gingivoplasty, gingival flaps, splinting). Antibiotic administration is generally not necessary following the definitive procedures. By waiting for several days following the initial scaling, there will be some healing, reattachment, and reduction of pocket depth, and the definitive procedures may not need to be as radical as would have been the case if the procedures were done as a single procedure.
When long-term results of teeth scaling with or without antibiotic treatment for several days at the time of scaling are compared in dogs where no follow-up frequent oral home care is provided, reduced pocketing and gingival inflammation can be demonstrated in the antibiotic-treated group. However, if the same study is conducted in dogs in which follow- up home care is provided, results are no better in the antibiotic treated group. The key to optimal management of oral health is on-going plaque control.
Dental scaling in an animal with evidence of systemic disease that may be worsened by bacteremia. Examples are: dogs with chronic heart failure or cats with cardiomyopathy, where the turbulent blood flow may increase the likelihood of development of endocarditis; and dogs with chronic kidney or hepatic failure, where metabolic instability may produce a secondary immunopathy or where septic vascular aggregates may exacerbate the systemic disease. Animals with primary immunopathies are another example, such as FIV or FeLV positive cats. Also, animals that are on immune-suppressive medication at the time of the procedure.
A scaling procedure in an animal in which a sterile clean or clean/contaminated surgical procedure will be performed during the same anaesthetic episode as the dental procedure. An example is an older animal with a mammary neoplasm and extensive periodontal disease, where, because of anaesthetic considerations relating to age and general condition, separate anaesthetic episodes are not recommended. If no antibiotic drug is given, the surgical wound will be seeded with bacteria from the dental bacteremia, and infection is very likely, with potentially disastrous results. Antibiotic administration is commenced at the time of administration of the pre-anaesthetic medications, and continued for 4-5 days, until the surgical wound has completed the initial inflammatory phase of healing.
Pulp capping procedure. Bacterial contamination of the pulp chamber at the time of pulp capping is the equivalent of seeding a closed cavity with bacteria, and may result in necrosis of the pulp contents and subsequent apical abscessation or fistula because there is no room in the pulp chamber to accommodate the swelling that the inflammatory response causes as it attempts to deal with the bacteria. Contamination may occur despite efforts to perform pulp-capping using sterile technique. A single dose of a bactericidal antibiotic will prevent seeded bacteria from becoming a focus of infection.
ANTIBIOTIC DRUGS AND DOSAGES FOR USE IN MANAGEMENT OF ORAL DISEASE
A. Anti-bacteremic therapy: Any bactericidal broad-spectrum antibiotic with particularly good activity against Gram + aerobic cocci and anaerobes, ie.. ampicillin (lOmg/kg IV [sodium salt] at time of pre-anaesthetic medication, or 20mg/kg orally an hour or more before inducing anesthesia) or amoxicillin/clavamox. For continuation treatment to prevent development of infection in surgical wounds that may be contaminated by dental-induced bacteremia, use ie.. ampicillin at 10mg/kg QID orally for 4-5 days.
Drugs used to treat periodontal bacterial infection or suppress bacterial growth in inflamed oral tissues. Clavamox (Smith-Kline Beecham) and Clindamycin (Antirobe, Upjohn Co) are selected principally for their broad spectrum activity and activity against anaerobes, and metronidazole, (Flagyl, Burroughs-Welcome) principally for its activity against anaerobes and flagellates. Clavamox (clavulanic acid-amoxicillin). Recent studies have shown that this is the most broadly effective drug against canine and feline oral anaerobes and aerobes. The dose rate is 5-10 mg/kg orally twice daily. Clindamycin is given at a dose rate of 1 mg/kg orally twice daily. This drug is effective against Gm + aerobes obligate anaerobes. It is concentrated in neutrophils and found in bone at a concentration similar to that found in serum. Metronidazole Recommended dose is 40-50mg/kg orally as a loading dose on the first day, followed by 20-25 mg/kg TID – use for 7 days or less at this dosage. When used intermittently to control chronic gingival or buccal ulceration, give at 10mg/kg BID, reducing to administration every second or third day based on response to treatment. The drug has antibacterial activity only against obligate anaerobes, with very few instances of development of resistance among susceptible microbes.
Chlorhexidine is a safe and effective oral antiseptic, active against all oral pathogens, and particularly effective against plaque organisms. As a 0.5% solution, it can be safely used as an oral rinse during preparation for oral procedures. It is available as a palatable 0.1% solution for daily home use as a plaque retardant or as a cleansing agent following oral trauma or when a metal or plastic device is required to be in the mouth for prolonged periods, and is also available in gel-dentifrice form. It loses its effectiveness rapidly when mixed with organic debris, so copious flushing is recommended.
Copyright Colin Harvey DVM