AVDS Dental Guidelines - Canine & Feline:
The Treatment of Periodontal Disease

Introduction

Oral care is necessary to provide optimal health and quality of life.  Diseases of the oral cavity, if left untreated can be painful and may contribute to other local or systemic diseases.

This paper follows from, and compliments the Guidelines covering a dental examination, formulation and implementation of the plan for a patient with no significant pathology.  It covers patients with established dental disease: periodontitis.

This document is believed to be current at the time of writing with regard to acceptable practice in Australia.

The purpose of this document is to provide guidelines to veterinarians to perform a ‘dental’ procedure in dogs and cats with established periodontitis.

This document includes more advanced treatments, which may include oral surgery and periodontal therapy.

The requirement for follow-up treatments will be derived from the result of the oral examination via the recognition of the presence of oral pathology, previous treatments and the degree by which the clinician anticipates improvement from this ‘dental’ procedure. 

Veterinarians are encouraged to be able to recognise whether their dental equipment and skill level allows them to fully treat the oral pathology present or whether referral to an appropriately trained veterinarian is required.
 
Definitions

• Dental prophylaxis (is a term synonymous with the colloquial term ‘dental’ utilised in this document) – a procedure including oral assessment under general anaesthesia, diagnosis and formulation of a treatment plan, removal of plaque and calculus above and below the gum line, an oral hygiene plan and subsequent followup. This procedure is limited to patients without periodontitis.
  
  
• Gingivitis – the reversible inflammation of the gingiva without the loss of the supporting structures that may or may not be visible to the eye.
  
  
• Periodontitis – the irreversible destructive process involving the loss of the tooth’s supporting structures (the periodontium) which includes the gingiva, periodontal ligament, cementum and the alveolar bone.
  
  
• Periodontal pocket – a pathological space between supporting structures and the tooth, extending apically from the normal site of the gingival epithelial attachment.
  
  
• Periodontal therapy – the treatment of chronic gingivitis and periodontitis.  Depending on the degree of periodontitis, this may require multiple examinations, treatments and disciplines.  Therapy may include periodontal surgery.
  
  
• Periodontal surgery – the surgical treatment of periodontal disease.
  
  
• Oral surgery – the surgical invasion and manipulation of hard and soft tissues to improve/restore oral health, function and comfort.

Oral examination, diagnosis and treatment planning

A full patient history is part of any oral examination.

The preliminary physical examination of all body systems is conducted in the consulting room. The extent of this initial examination will depend on the temperament of the animal.

The temperament of the animal and the commitment of the owner are assessed at the initial examination as these will influence the ´home-care´planning.

Complete oral examination can only be performed with the animal anaesthetised; excessive calculus deposits may need to be removed to aid in the more accurate measuring of pocket depths with a periodontal probe. 

A comprehensive oral examination should be performed and will include periodontal probing; the use of special tests including intraoral radiographs is highly recommended.

All findings should be recorded on a dental chart which forms part of the animal’s medical record.

The indices that are highly recommended to be recorded on the dental chart are fully detailed in the procedures section of this document.

Based on the findings of these examinations, diagnoses will be made.

Consideration of the diagnoses, patient co-operation and owner commitment will permit the development of an appropriate treatment plan.

Procedures

The treatment of periodontitis is performed on a patient with existing periodontitis (attachment loss) or with compromised or damaged dentinal structures.

Stages in dental assessment and treatment:

• Under general anaesthesia, the oral cavity is examined, assessed and graded.  Findings are recorded on a dental chart and a treatment plan is formed. Intra-oral radiographs are taken to further assess the significance and extent of pathology.
• Scaling using hand and power instruments is performed and the dental chart adjusted for any other findings at this time.
• Teeth to be retained are polished.
• Periodontitis and other pathology is treated with the informed consent of the owner: closed or open* curettage and/or root planing of subgingival pockets.   *A flap would be raised to allow this procedure.
• Extraction of teeth may be indicated for the treatment of:
• Tooth retention (as in the case of deciduous teeth),
• Supernumerary teeth,
• Fractured teeth (that are not to be endodontically treated)
• Periodontally compromised teeth
• Crowded teeth
• Endodontically compromised teeth (that are not to be endodontically treated)
• Perioperative adjunctive therapy (antibiotics, local anaesthesia, analgesia etc) should be administered where indicated (refer Appendices 1 and 2).

Post-operative communication
An informed client is essential to the procedures planned and being performed and to the success of ongoing oral care, this is especially important in cases involving periodontal disease.
 
The operative procedures planned along with any existing or potential complications (e.g. bleeding, coughing, dehiscence, infection, neurological signs, halitosis, vomiting diarrhoea, anorexia and/or signs of pain) should be discussed. 

Discuss immediate postoperative homecare including medications and their side effects. 

Provide antibiotics and medication for inflammation and pain as indicated (refer Appendices 1 and 2).

Discuss any recommended changes in diet that are deemed necessary: such as a change to soft or premoistened food or to a prescription diet. 

Provide individualized oral and written instructions at the time of discharge. 

Establish an appointment for follow-up examinations.

Appendix 1
Antimicrobial usage in periodontal Disease

Introduction
Periodontal diseases (PD) are a number of plaque (bacterial) induced diseases of the supporting structures of teeth.

The two main forms of PD are gingivitis, the reversible inflammation of the gingiva, and periodontitis, the inflammation and irreversible destruction of the tooth’s supporting structures, namely the gingiva, the periodontal ligament, cementum and alveolar bone.

Antimicrobial therapy (adjunctive therapy) in the management of PD
Bacteraemia can occur during dental procedures, mastication and tooth brushing (Nieves et al., 1997). The degree of the bacteraemia is not based on the severity of the periodontal disease. In a healthy animal, the bacteraemia is usually cleared in about 20 minutes.

Antimicrobials (including antiseptics and antibiotics) are used in the management of periodontitis in veterinary dentistry.

Antimicrobial (AB) usage has often been based on the belief that because PD is caused by a bacterial infection, and ABs kill or control the growth of bacteria, ABs should play an integral part in the treatment of this infection.

Often, the choice of AB is decided on empirical grounds.
However, the management of PD is quite different from the treatment of most bacterial infections for a number of reasons:

• The bacterial flora present is always heterogenous and relatively complex (is a biofilm) and often varies from animal to animal.
• The presence or absence of a single bacterial species cannot be directly correlated with disease presence or its absence.
• PD is often asymptomatic in its earlier stages.
• The host response itself contributes to disease progression.

Before prescribing ABs, the clinician must consider such issues as choice of antimicrobial, dosing regimen, length of treatment, evaluation of treatment outcome and short and long term benefits from adjunctive antibiotic therapy.

The clinician must resist pressure from pet owners to prescribe ABs in the absence of any other periodontal therapy.

The use of ABs without appropriate periodontal therapy is not acceptable practice; this is based on the difficulty of antimicrobial penetration into the plaque biofilm, unless that biofilm has been disrupted by mechanical debridement.

Choice of antimicrobial
Rational prescribing of antibiotics would include the selection of the AB with the narrowest spectrum of activity against known periodontal pathogens, the least side effects and the use of so called ‘first line Abs’, saving other agents for when resistance is encountered.   This choice is often tempered with the practical influence of ‘client compliance’ or capability.

Antimicrobials such as Amoxicillin-clavulanate, Clindamycin hydrochloride, and Metronidazole seem to be particularly effective against periodontal pathogens based on pharmacokinetic and clinical studies (Sarkiala and Harvey,1993). Topical Chlorhexidine gluconate is also very effective against plaque bacteria and can be used following more complex periodontal therapies where a tooth brushing regime may be uncomfortable for the pet at least initially.

The long term benefit of AB usage in PD is currently not proven.

Specific recommendations for antimicrobial usage (combined with a dental clean under General Anaesthesia)
Prior to periodontal therapy, the oral cavity should be flushed with a dilute solution of chlorhexidine (0.12-0.2%). This will help reduce the bacterial aerosol that occurs during mechanical scaling reducing aerosol exposure to both the operator and assistants.

No antimicrobials are necessary, apart from pre-cleaning rinsing of mouth with Chlorhexidine gluconate, for the treatment of Grade 0 dental disease (no disease) to Grade 2 (<25% attachment loss*) in otherwise healthy animals.

The use of antimicrobials is warranted during the treatment of Grade 4 periodontitis (>50% attachment loss) or acute periodontal abscesses / cellulitis or animals undergoing periodontal surgery such as open root debridement#.

The choice of antimicrobial is usually based on empirical grounds, but Amoxicillin-clavulanate, Clindamycin hydrochloride, Doxycycline hydrochloride and Metronidazole are sound choices being effective against most periodontal pathogens.

Antimicrobials can be given peri and post-operatively.

If the animal is systemically unwell, a pre-operative course may be recommended starting 2-3 days prior to the dental cleaning.

The use of locally delivered antimicrobials into the periodontal pocket is also warranted.

In animals that are immunocompromised, immunosuppressed or systemically unwell, have cardiac blood flow disturbances such as a heart murmur, the recommendation is as for grade 4 periodontitis patients.

 * Attachment loss refers to the loss of periodontal attachment surrounding the tooth.  It is measured from the cemento-enamel junction, to the depth of the periodontal pocket.

# Periodontal surgery involves a number of procedures which include the removal of plaque by direct visualisation of the root surface (by raising a mucoperiosteal flap), the reduction of pocket depth, crown lengthening and periodontal regeneration techniques.

Appendix 2
Analgesia in dental treatments

Local anaesthesia:
Delivered most commonly as nerve blocks but may also be injected subgingivally as an infusion over the tooth’s root apex (as is commonly the practice in human dentistry) and always to be used pre-emptively.

Duration of action is determined mainly by the agent: Lignocaine has a fairly rapid onset (10-15 mins) and short duration (1-2 hours) whereas Bupivicaine has a slow onset (20-30 mins) and a long duration (4-6 hours). 

NSAIDS and Opioids:
These are the mainstay agents of analgesia in small animals:

• NSAIDs

Effect: analgesia, antipyresis and anti-inflammatory.
They are not ‘controlled’ as are the opioids (less ‘red tape’) and can provide excellent analgesia but care must be taken regarding gastrointestinal, renal and hepatic function.

Most adverse reactions are associated with GI upsets, renal adverse effects are less common but animals with renal compromise are predisposed.

Perioperative IV fluid therapy is highly recommended to support renal perfusion.
There is no evidence of benefit in the use of pre-operative NSAIDs.

• Opioids

Opioids don’t have the potential to induce renal dysfunction like the NSAIDs and they provide some sedation.  Higher dose alter the level of consciousness, causing narcosis.

Morphine is the prototype of the opiates and as it causes respiratory depression with higher doses, care should be taken with cases involving CNS or respiratory disease.  It causes nausea and vomiting initially, constipation later.  Even low dose constant rate infusions (CRI’s) of morphine cause heavy sedation requiring constant monitoring during administration.

Buprenorphine (‘Temgesic’) at higher doses (0.03-0.04mg/kg SC is recommended for post-Sx analgesia providing pain relief without sedation, therefore patients may be comfortable enough to get up and move about, also to eat & drink.  It has a slow onset and a long duration of action (8-12 hours; half-life of 5 hours).  As it is metabolised by the liver, renal excretion is minimal.

Fentanyl is a highly lipid soluble, short acting opioid analgesic.  Duration of action is between 30 mins and 2 hours.

Transdermal drug delivery:
This form of administration of opiates has been specifically designed for human use but has been examined and used in veterinary species.

The Fentanyl patch (Duragesic) of 100ug/hr is therapeutically equivalent to 60mg morphine.  The drug is absorbed across the skin and taken up systemically.  Patches deliver Fentanyl for at least 72 hours.  A potential downside is that the dose depends on the patch’s surface area but may be variable amongst patients releasing between 27-98% of the theoretical value.

Methadone has a long duration of action (hence usefulness in heroin addicts as withdrawal is inversely related to intensity of withdrawal symptoms). 

IV administration has a rapid onset of action and is useful for acute pain.

A combination of ACP (0.01-0.02mg.kg) and Methadone (0.2-0.4mg/kg) SC provides excellent sedation and analgesia in 5-10 minutes.

This document has been developed and produced by the committee of the Australian Veterinary Dental Society, 2007.