Understanding tusk anatomy
Tusks are modified canine teeth, which erupt in both male and female pigs between 10-15 months of age (Fig 1). Tusks continually grow throughout life. The growth rate depends on sex, reproductive status, and time of sterilization. The tusks of males generally grow faster than in females. Intact sows and boars also have a faster tusk growth rate than spayed or castrated pigs. If an animal is sterilized after puberty, the rate of tusk growth is faster than if he or she was sterilized prior to the onset of puberty. Nevertheless, this growth is much slower than if the pig were left intact.
Why should tusks be trimmed?
Tusks are incredibly sharp and even lightly brushing against a tusk can cause abrasions and lacerations. Bites sustained from a pig with untrimmed tusks can cause significant damage. Untrimmed tusks can grow long and can even curl enough to penetrate the lip of the pig.
The frequency of tusk trims will vary; however, females generally need tusk trims every 12-24 months and males need tusk trims every 6-12 months.
- Gloves, eye protection, face mask
- Tongue depressors
- I prefer the high speed dental drill with long straight drill bit (e.g. 701L or 702L)
- High speed rotary hand tool (e.g. Dremel®) with sanding or cutting bur
- Obstetrical or Gigli wire
Note: Cutting and crushing instruments, such as nail trimmers and hoof trimmers, are NOT RECOMMENDED.
- Damage to adjacent soft tissue structures and subsequent abnormal growth patterns
- If the tusk is trimmed too short, the patient is at risk for developing a root abscess from an ascending infection.
- The patient is also at risk for crown fractures when cutting or crushing instruments are used.
These instructions are intended for tusk trims using high-speed dental drills, however this procedure can be extrapolated for use of high-speed hand rotary tools.
- Fast the pig for 12-24 hours in preparation for sedation, which will ensure a safe and comfortable experience for the pig. The onset of action for my preferred sedation regimen (Table 1) is 5-15 minutes. Sedation with this combination typically lasts 20-45 minutes.
Table 1. “Drunk Pig Cocktail” Agent Dosage Route Midazolam 0.2 mg/kg Administered together as a single intramuscular injection Dexmedetomidine 0.02-0.04 mg/kg
Butorphanol 0.2-0.4 mg/kg See Step 10 for advice on sedation reversal
- Position the patient in lateral recumbency.
- Direct the head downwards by placing towels beneath the shoulders and neck or lightly positioning the snout off the edge of the table.
- Turn water flow on the dental unit to 50%.
- Place a tongue depressor behind the tusk to be trimmed to protect underlying soft tissue structures.
- Trim perpendicular to tusk growth, NOT parallel with the gingival margin.
- To avoid the pulp cavity, it is crucial that the tusks be trimmed 3-4 cm above the gingival margin (Fig 1).
- Smooth the cut surface to remove all sharp edges (Fig 8).
- Repeat the process bilaterally on the maxillary and mandibular tusks.
- Sedation can then be reversed using flumazenil (0.004mg/kg IM) and atipamezole (0.2mg/kg or 200 μg/kg) IM.
Both males and female pigs possess modified upper and lower canine teeth or tusks, however, the tusks of the male retain an open root that allows these teeth to grow throughout life. Tusks can become long and extremely sharp. Therefore tusk trims may be necessary to prevent injury to humans and other animals or damage to household furniture or flooring. Tusks can even harm the pig itself after becoming caught on caging or growing long enough to penetrate the individual’s flesh. Tusks should be trimmed well above the gum line to avoid the pulp cavity. Intact males may require a tusk trim every 6-12 months.