Hyperplastic Feline Juvenile Gingivitis

Gero December 6, 2019

Hyperplastic feline juvenile gingivitis is often confused with feline juvenile periodontitis and/or feline chronic gingivostomatitis (feline stomatitis). Both of the latter have the defining characteristics that distinguish them from juvenile feline hyperplastic gingivitis. Knowing these characteristics allows the practitioner to make informed decisions on treatment and referral to a veterinary dental specialist.

What Is Juvenile Feline Hyperplastic Gingivitis?

Juvenile feline hyperplastic gingivitis is a pronounced generalized inflammation and overproduction of the attached gingival (gum) tissues in the young cat. (Figure 1) It is typically diagnosed around the time of tooth eruption between 7-10 months of age. Certain breeds are over-represented including Maine Coon, Siamese, Abyssinian, and Somali.

Figure 1 – Hyperplastic Feline Juvenile Gingivitis limited to the attached gingiva of the left maxillary premolars. The inflammation is limited to the attached gingiva.

It is distinguished from another common oral inflammatory disorder in the cat by the absence of inflammation in the caudal oral mucosa as seen in feline gingivostomatitis. (Figure 2)

Figure 2 – Caudal oral mucositis is a diagnostic of chronic feline gingivostomatitis ais seen here unassociated with the teeth in the back of the mouth (behind the two strings of saliva). This easily distinguishes this condition with juvenile gingivitis and juvenile periodontitis.

Inflammation in cats with hyperplastic feline juvenile gingivitis is confined to the attached gingiva and coronal gingival overgrowth is a hallmark sign. Contrast this to feline juvenile periodontitis where overgrowth onto the crown is not present. (Figure 3)

Figure 3 – This is a cat with feline juvenile periodontitis. Gingival overgrowth onto the crown is not present.

The etiology of this disease is unknown, but one possible cause is an inappropriate host immune response to plaque biofilm. Histopathology may be indicated if an underlying condition is suspected or the clinical appearance is atypical. FeLV and FIV viral status should be evaluated as a general rule in cats with any oral inflammation as this may be a sign of either.

Typically in cats with hyperplastic feline juvenile gingivitis, periodontitis changes, including alveolar bone loss, gingival resorption, pocket formation, or root exposure, are not seen initially but may result when proper treatment is not initiated early.

If oral inflammation can be controlled by in-hospital cleaning under anesthesia and home care for the first 2 years of life, recurrence may be decreased or prevented altogether. Many patients respond to this regimen of frequent oral health maintenance. On the other hand, juvenile cats with this form of oral inflammation who are not controlled aggressively at a young age suffer permanent anatomical changes and frequently progress. With hyperplastic feline juvenile gingivitis, intense gingivitis may begin at the time of tooth eruption, progressing to periodontitis without aggressive early treatment. In many cases, the inflammation is limited to the attached gingiva and does not extend into the oral mucosa or bone as it does in feline juvenile periodontitis. (Figure 4)

Figure 4 – Bone loss adjacent to the left mandibular molars and premolars in a young cat with feline juvenile-onset periodontitis. This is not typically seen in hyperplastic feline juvenile gingivitis unless treatment is not instituted or otherwise not effective.

What Are the Clinical Signs of Juvenile Feline Hyperplastic Gingivitis?

There is a pronounced inflammation of the attached gingiva., often followed by
Marked hyperplasia of the tissue extending onto and often covering the crown of the tooth
Pseudopocket formation as a result of the overgrowth of tissue onto the crown.
Although cats rarely show clinical signs inflamed gingiva may bleed when touched during eating.
Lack of caudal oral mucosa inflammation as seen with feline lymphocytic-plasmacytic gingivitis/stomatitis
Commonly first observed in cats 5-7 months of age
Oral malodor, bleeding, inappetence, and dysphagia are not generally seen

How Is Juvenile Feline Hyperplastic Gingivitis Diagnosed?

Oral examination and dental radiographs are the most important diagnostic tools. Young cats with oral inflammation require detailed oral and dental assessment under anesthesia with dental radiography. The lack of bone loss on radiographs and the absence of caudal oral mucositis is strongly suggestive of feline juvenile feline hyperplastic gingivitis. Young cats with alveolar bone loss prior to one year of age are strongly suggestive of feline juvenile periodontitis and helps to differentiate the two conditions. Cats with feline juvenile periodontitis generally do not have significant gingival overgrowth. This is very helpful in diagnosis with cats over one year of age.

What is the Treatment for Juvenile Feline Hyperplastic Gingivitis?

With diligent treatment, the condition may regress by 18 months to two years of age. Complete plaque control is critical, and owner commitment to aggressive treatment is mandatory to have any chance of achieving remission. (Figure 5 and 6) The mainstay of treatment is frequent (q. 3-4 months) dental prophylaxis, excision of hyperplastic tissue (gingivectomy) and full mouth radiographs. The prophylaxis portion with cleaning and polishing needs to be performed to remove plaque accumulation even if there is no visible calculus.

Figure 5 – Hyperplastic feline juvenile gingivitis in a young cat prior to treatment.

If present the extraction of persistent deciduous teeth is necessary. Young cats with a hyperplastic response require gingivectomy to remove pseudo pockets and create an environment more amenable to plaque control.

Figure 6 This is the same cat in Figure 4 three months after gingivectomy, cleaning, polishing and home care. Note: Despite no obvious plaque, prophylaxis is important every 3-4 months until 18 months – 2 years of age in these patients.

A biopsy of the tissue should be considered. Some advocate PCR testing for Calicivirus, performed from a piece of the gingiva or a cytobrush swab. Diligent home plaque control will significantly influence the outcome. Brushing is the best at accomplishing plaque control however this is rarely performed due to the lack of owner and/or patient compliance. More likely treatments include dental formulated diets, chlorhexidine rinses, gels, and dental treats, Water additives allow total mouth immersion each time a patient drinks and may provide the best option. Home care options that have achieved the Veterinary Oral Health Council (VOHC) seal of approval are recommended. This list of all approved home care products for dogs and cats can be accessed here: www.vohc.org

These patients may also benefit from concurrent incorporation of immunomodulation as well as the recommended professional and home plaque control. Feline interferon omega, low dose daily doxycycline and topical application of TetraDecanol Complex (TDC) can be considered.

This discussion should help the veterinarian in general practice recognize juvenile feline hyperplastic gingivitis and differentiate it from feline juvenile periodontitis and/or feline chronic gingivostomatitis (feline stomatitis). This will allow proper early management and treatment which are required to prevent progression into adulthood.