AVDC Veterinary Dental Disease Scoring Reference
AVDC periodontal stage 0–4, dental fracture classifications, and common findings.
AVDC Periodontal Disease Stages
| Stage | Definition | Treatment |
|---|---|---|
| PD 0 – Normal | Clinically normal periodontium | Routine prophylaxis and home care |
| PD 1 – Gingivitis only | Inflammation, no attachment loss | Professional cleaning + home care; fully reversible |
| PD 2 – Early periodontitis | < 25% attachment loss | Subgingival scaling + root planing + improved home care |
| PD 3 – Moderate periodontitis | 25–50% attachment loss | Periodontal surgery vs extraction; aggressive home care |
| PD 4 – Advanced periodontitis | > 50% attachment loss | Extraction usually indicated |
Dental fracture classification
| Type | Definition |
|---|---|
| Enamel infraction | Crack in enamel only, no enamel loss |
| Enamel fracture | Loss of enamel, no dentin exposed |
| Uncomplicated crown fracture | Dentin exposed, pulp not exposed |
| Complicated crown fracture | Pulp exposed - endodontic treatment or extraction |
| Uncomplicated crown-root fracture | Dentin exposed, extends below gum line |
| Complicated crown-root fracture | Pulp exposed, extends below gum line |
| Root fracture | Cementum, dentin and pulp involved |
Common findings & next steps
| Finding | Implication |
|---|---|
| Tooth resorption (cat) | Extraction usually indicated; treat for pain. |
| Persistent deciduous teeth | Extract by 7 months to prevent malocclusion. |
| Class I malocclusion | Normal jaw length but tooth(s) malpositioned. |
| Class II / III malocclusion | Skeletal jaw discrepancy - usually genetic. |
Definitive staging requires intraoral radiographs and periodontal probing under anaesthesia - visible calculus alone underestimates disease severity in most patients.
Frequently asked questions
What is the difference between PD1 and PD2?
PD1 is gingivitis only - no attachment loss. PD2 has < 25% attachment loss visible on radiograph (early periodontitis). The jump from PD1 to PD2 is irreversible bony change, which is why scaling at PD1 has the highest preventive impact.
When does a fractured tooth need extraction?
Any complicated crown fracture (CCF) exposing the pulp needs extraction or endodontic treatment - the pulp inevitably becomes infected. Uncomplicated crown fractures (UCF) can be monitored if the tooth remains vital on radiograph.
Are tooth resorptions painful in cats?
Yes - tooth resorption (TR) in cats is universally painful by the time it's clinically visible. Extraction is the only effective treatment; restoration is contraindicated.