The ABCs of veterinary dentistry: H is for hair havoc

Figure 1. Two hairs embedded in the folds of the incisive papilla in a dog. (All photos courtesy of Dr. Jan Bellows.)

When I told the editor of dvm360 this article would not be about halitosis, she was surprised. Virtually all companion animal practitioners know that halitosis is the presenting sign of periodontal disease and know how it can be treated and prevented. On the other hand, hair caught in oral cavity crevices in dogs and cats is less well-known and needs to be recognized, treated and prevented-hopefully before damage is done (Figure 1).

Types of hair

There are two general hair classifications in dogs and cats: short and long.

Short-haired breeds have hair less than 5 cm long that lies close to the body. Most short-haired dogs have more stiff topcoat hair and less soft undercoat hair. Canine examples include the beagle, Irish terrier, greyhound, English toy terrier, boxer, English bulldog and German shorthaired pointer. Examples of short-haired cats include the American shorthair, Bengal cat and European shorthair.

Long-haired breeds have hair longer than 5 cm. Canine breed examples include the Pekinese, shih tzu, cocker spaniel, golden retriever and German shepherd. Long-haired cat breeds include the Maine coon, German angora and Norwegian forest cat.

Where does the aberrant hair show up?

Hair doesn't grow in the oral cavity. But much like grass awns, stiff, coarse short hairs of short-haired breeds can become embedded in the oral cavity when dogs and cats gnaw or lick their skin due to allergies, external parasites or obsessive-compulsive disorders, creating foreign body inflammatory reactions that can destroy the periodontal attachment, leading to tooth loss.

Gingival sulcus: Most commonly, hair embeds in the gingival sulcus surrounding the maxillary and mandibular incisors and canines (Figure 2).  

Figure 2. Hair embedded in the gingival sulcus of the right and left maxillary first and second incisors.

Tongue: Some dogs lick their skin instead of gnawing or biting at it. This leads to hair becoming  embedded in their tongues (Figure 3).

Figure 3. Hair embedded in a dog's tongue.

Between malpositioned teeth: Teeth are normally separated by sufficient gingiva, creating a self-cleaning process by which food and debris slide off the dental hard tissues into the mouth. In areas where teeth are rotated or malpositioned, hair can become trapped between the teeth (Figure 4). 

Figure 4. Hair embedded between the left and right maxillary malpositioned second and third premolars in an English bulldog.

The root of the havoc

The embedded section of the hair that lies subgingivally acts as a foreign body. Bacteria and oral debris attach to the hair and generate an inflammatory response, resulting in pocket formation. If the client does not provide mechanical dental home care (tooth brushing or daily wipes to control plaque), the inflammation progresses apically and diminishes the tooth's gingival attachment.

How to handle the havoc

Hair in the oral cavity is often recognized during a wellness exam or during the intake inspection prior to an oral assessment, treatment and prevention (Oral ATP) visit.

Once the dog or cat is anesthetized, scale, polish and irrigate the teeth to remove implanted hairs. Then conduct a tooth-by-tooth examination, including probing and a full mouth intraoral radiographic examination. Though diagnostically important, radiographs are often unable to show periodontal disease detected with the periodontal probe (Figures 5A, 5B, 6A and 6B).

Figure 5A. A periodontal probe before insertion into the right maxillary first incisor pocket.

Figure 5B. A 6-mm pocket caused by embedded hair. Extraction is indicated.

Figure 6A. Marked inflammation and periodontal disease affecting the right and left maxillary first and second incisors secondary to embedded hair.

Figure 6B. A radiograph only reveals moderate support loss of the left first and second incisors.

Periodontal disease caused by hair is graded in stages:

Stage 1 (PD 1): Gingivitis only; no attachment loss. The height and architecture of the alveolar margin are normal. Treatment includes ultrasonic dental scaling, polishing, irrigation and hair removal. 

Stage 2 (PD 2): Early periodontitis; less than 25 percent of attachment loss or, at most, there is a stage 1 furcation involvement in multirooted teeth. In addition to hair removal, treatment can include root planing inserting local antimicrobials, such as Clindoral (TriLogic Pharma) or Doxirobe Gel (Zoetis), subgingivally where pockets are present.

Stage 3 (PD 3): Moderate periodontitis; 25 to 50 percent attachment loss as measured by either probing the clinical attachment level or by radiographic determination of the distance of the alveolar margin from the cementoenamel junction relative to the length of the root. Or, there is a stage 2 furcation involvement in multirooted teeth. Treatment includes hair removal, root planing, the possible insertion of local antimicrobials subgingivally where pockets are present and owner commitment to twice daily plaque control. Extraction is also a possibility (Figures 7A and 7B).

Figure 7A. A 6-mm periodontal pocket affecting the right maxillary first incisor secondary to embedded hair (same patient imaged in Figure 4).

Figure 7B. After extraction of the maxillary incisor and third premolars.

Stage 4 (PD 4): Advanced periodontitis; more than 50 percent of attachment loss as measured by either probing the clinical attachment level or by radiographic determination of the distance of the alveolar margin from the cementoenamel junction relative to the length of the root. Or, there is a stage 3 furcation involvement in multirooted teeth. Treatment includes hair removal and extraction (Figures 8A-8D and 9A-9F).

Figure 8A. Advanced periodontal disease affecting the first and second incisors secondary to inflammatory response to embedded hair.

Figure 8B. A mucogingival flap raised to extract the maxillary right and left first and second incisors.

Figure 8C. Flap closure.

Figure 8D. The healing incisor surgical sites.

Figure 9A. Hair foreign bodies creating marked periodontal disease in the rostral maxilla in an English bulldog. 

Figure 9B. Subgingival hair extending from the canine marginal gingiva and at the mucogingival junction. 

Figure 9C. A probe extending through the attached gingiva.

Figure 9D. Gingivectomy around the canine and third incisor to remove periodontal pockets.

Figure 9E. A laser used to decrease the amount of gingiva enlargement.

Figure 9F. One month after surgery the gingiva has healed and inflammation has resolved, with a few new embedded hairs present.

Hair embedded in a dog's tongue can be removed using forceps, followed by carbon dioxide laser ablation of the inflamed areas. Multiple monthly laser treatments are often required to resolve the issue (Figures 10A-10C).

Figure 10A. Removing hairs with forceps.

Figure 10B. A carbon dioxide laser used to decrease the amount of bacteria and inflamed tissues and encourage scar formation.

Figure 10C. Decreased inflammation two months after laser therapy.

Preventing recurrence

First, investigate why the dog or cat is licking and chewing on its skin. Is it secondary to obsessive-compulsive disorders, parasites (e.g. fleas, ticks, Demodex species mites), infection (e.g, folliculitis) or an allergy to food or to something in its environment? It is much better to treat the underlying cause than to treat the dreadful effects. 

After removing the hairs and treating the gingival and periodontal diseases present, have your client examine the pet's mouth daily, paying close attention to embedded hairs emerging from the marginal gingiva. Teach your client how to use a cotton-tipped applicator to tease the hairs out of the periodontal pockets (Figures 11A-11D)

Figure 11A. Deeply embedded hairs populating the gingiva surrounding the maxillary and mandibular canines as well as the visible incisors.

Figure 11B. A long cotton-tipped applicator used to tease hair from the gingival pocket.

Figure 11C. More embedded hairs exposed.

Figure 11D. Most of the hairs have been removed from the mandibular canine gingiva.