Photo 9B: This view is from the lingual aspect of the mandible to demonstrate the mandibular foramen for the caudal mandibular
Feline anatomical differences
Anatomical differences between species require slight variations in technique when considering nerve blocks in cats. When
performing the rostral maxillary (infraorbital) nerve block in cats, the approach is the same as described in the dog, but
the infraorbital foramen is relatively more dorsal in the cat. Therefore, the needle should be inserted more dorsally and
then advanced in a rostral-to-caudal direction into the infraorbital foramen. As in the dog, the needle should not engage
bone and should pass directly into the foramen.
Photo 10: Radiopaque dye infused local anesthetic mixture placed at the level of the mandibular canal for the caudal mandibular
block to demonstrate the extensive diffusion along the mucosa/bone interface.
The infraorbital canal in cats is much shorter, and the foramen relatively larger than that found in the dog (Photo 11). Because
the canal is only a few millimeters long, administration of the agent into the canal places it adjacent to the infraorbital
and pterygopalatine nerves. This results in creating the same effect as the caudal maxillary nerve block in dogs. In this
discussion, it is suggested that the single nerve block for the cat maxilla be termed the maxillary nerve block since it is
performed as is the rostral maxillary block in dogs but blocks the same region as the caudal maxillary block.
Photo 11: The arrow shows the infraorbital foramen in the cat. Please note that it is only a few millimeters in length.
Cats have no mandibular first and second premolars; therefore the middle mental foramen in the cat is located midway between
the mandibular canine and third premolar (Photo 12). Only in very small cats is this foramen not accessible to needle placement
for administration of the rostral mandibular block. If one encounters difficulty, the caudal mandibular block is an alternative.
Figure 12: The arrow demonstrates the location of the middle mental foramen, the landmark for needle introduction in the rostral
mandibular block in the cat.
Regional nerve blocks for oral surgery are valuable tools in enhancing patient safety intraoperatively and patient comfort
postoperatively. They are easy to administer and require no special equipment to perform. Their use encourages quick return
to normal mastication and continuation of normal food and water intake shortly after oral procedures. Incorporation of oral
regional nerve blocks into the dentistry service is paramount in providing the best in patient care. Simplification and clarification
of nomenclature should be considered to eliminate confusion between descriptions of actual anatomical regions and the nerves
Brett Beckman, DVM, FAVD, Dipl. AVDC practices referral dentistry at Affiliated Veterinary Specialists, Orlando, Fla.; Noah's
Animal Hospitals in Indianapolis; and at Florida Veterinary Dentistry and Oral Surgery in Punta Gorda, Fla. He is president-elect
of the American Veterinary Dental Society and diplomate of the American Academy of Pain Management.
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