ETIOLOGY/PATHOPHYSIOLOGY

Dogs/cats
- Genetics: probable familial tendency—boxers
- Hyperplastic response of gingival epithelial cells to likely due to chronic antigenic stimulation of periodontal components
- Sometimes seen as a sequela to certain medications: diphenylhydantoin, cyclosporine, nitrendipine, nifedipine

SIGNALMENT/HISTORY

Certain breeds: boxers, Great Danes, collies, Doberman pinschers, Dalmatians
Gradual thickening and elongation of gingival margins
- May have oral odor (see Chapter 24)

CLINICAL FEATURES

Thickening and increase in height of attached gingiva and gingival margin, sometimes completely covering tooth surface
Resultant formation of “pseudopockets”: increase in pocket depth due to increased gingival height, not due to loss of attachment, unless untreated and progresses to concurrent periodontal disease (Fig. 27-1)
Gingival margin may be symmetrically enlarged, especially at incisors
Locally affected areas possible (shelties), but typically more generalized pattern found
Locally affected areas other than the marginal gingiva may develop hyperplastic areas due to chronic irritation, such as the “gum chewers” lesion in this patient’s mucosa (Fig. 27-2); these areas should be evaluated for therapeutic need
May form as protruberant masses (grape cluster) at gingival margins; biopsy necessary to rule out neoplasia

Figure 27-1 Gingival hyperplasia is an overgrowth of the gingival margin that causes a deeper pocket, not due to attachment loss (pseudopocket).

Figure 27-2 While not a true gingival hyperplasia, local irritations of the buccal or lingual mucosa, such as with “gum chewers” syndrome, can present with similar signs and need for evaluation for therapy and/or biopsy. The additional hyperplastic tissue adjacent to the first and second molars should also be evaluated.