Comparative Anatomy of the
Buccinator Muscle in Cat
(Felis domestica)
Tomo, Soichiro, Tomo, Ikuko, Nakajmia, Koh,
Townsend, Grant C., & Hirata, Kazuaki,
“Comparative Anatomy of the Buccinator
Muscle in Cat (Felis domestica).” The
Anatomical Record, Volume 267, Issue 1,
Pages 78 – 86.
Published Online: 25 April 2002
Taxonomy
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Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Felidae
Genus: Felis
Species: domestica
Background Information
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WHAT IS A BUCCINATOR MUSCLE?
It is a muscle located underneath the
orbicularis oris muscle. It arises from the
lower buccal membrane and from the molar
region of the alveolar border of the mandible.
This muscle may aid in mastication which
includes suckling, and expelling air forcibly.
Cats have often been used for experimental
research because their uniform shape make
them more suitable for physiological
experimentation.
There are only a few reported studies on the
buccinator muscles of cats.
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The buccal part of the buccinator muscle in the
cat has been discovered by a
Japanese/Australian research team at The
University of Adelaide's Dental School.
These researchers found a technique in which
they traced nerves into muscles and classified
musculature according to the innervation (to
supply with nerves).
*- Represents the Buccinator Muscle
Hypothesis
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The goals of this study were:
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(1) to identify the buccinator muscles
in the cat and to report on its
anatomical features in detail.
(2) to clarify the homology of the
buccinator in mammals.
Methods and Materials
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Dissections of the facial muscle were carried
out in 12 specimens of adult cats (6 males and
6 females).
They were fixed with 10% formalin, and then
transferred to 70% ethanol.
The upper parts of their cervical columns were
removed and their heads were cut in half in a
sagittal plane.
In each dissected specimen, the skin was
removed following the underlying superficial
layer of the facial muscles.
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The species were immersed in water for further
dissection, and the facial muscles were
observed.
Their innervations, arteries, and veins were
traced under a binocular microscope.
Figure: Superficial nerves of the face in cat: lateral view, left side. The platysma
and orbicularis oris have been reflected. (a) The dorsal ramus of the facial nerve
divided into a temporal branch and a zygomatic branch. The buccal nerve ran laterally
to the buccinator muscle. (b)The auriculotemporal nerve of the mandibular nerve
anastomosed with the ventral branch ramus of the facial nerve (c) under the eyelid. A
branch from the ventral ramus of the facial nerve and the buccal nerve of the
mandibular nerve anastomosed and innervated the buccinator muscle in most of the
cases. BC, buccal nerve; OO, orbicularis oris; MG, molar gland; MS, masseter; PD,
parotid grand; PL, platysma.
Results and Discussion
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The buccinator was identified underneath the
orbicularis oris muscle and it was located deeper
than the other facial muscles.
The muscle was determined to be approximately
3mm wide at its origin and 4mm wide at its
insertion.
It was 11mm in length from origin to insertion.
Males > Females (cats).
The muscle was determined to be smaller than
the buccinator muscles of dogs and humans.
Classification of the buccinator muscle is not
consistent in different mammals.
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The buccinator muscle in cats is different from the
buccinator muscle of humans because in humans the
muscle arises from the mandible and the maxilla.
Similarities of the buccinator muscle of cats and
humans were;
 1) innervated by facial nerve
 2) supports buccal muscle
 3) inserts into the modiolus (auditory nerve fiber)
 4) its bundles run antero-posteriorly
 5) posterior part of the muscle is located medially to
the masseter muscle
 6) parotid duct, facial nerve, artery, and vein run
lateral to the muscle.
 7) located deeper than other facial muscles
 8) buccal nerve runs on its surface.
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The findings of the structural similarity of the
buccinator muscle in cats and humans opens up
new opportunities for future experimental work on
aspects of masticatory function.
This anatomy has provided insights into the
homology of the buccinator muscle but further
studies of the facial musculature in other
mammals are needed to confirm whether the
findings are applicable.
Comparative
classification of
the buccinator
and orbicularis
oris muscles
a. Muscles run
longitudinally like
the buccinator
muscle in humans.
b. Muscles
originate medial to
the masseter
muscles.
Buccal
region
Oral region
Mammal
studied
M.
buccinatoriusab
M. orbicularis oris
Primates
M. buccinatorab
M. orbicularis oris
Armadillo
M. buccinatorab
M. orbicularis oris
Rodents
M. buccinator
Wild Boar
M. buccinator
Domestic
Sheep
M.
buccinatoriusab
M. orbicularis oris
Elephant
M. buccinator
M. orbicularis oris
Cattle and
Buffalo
Figure: Innervation of the buccinator muscle in cat: lateral
view, left side. A branch of the facial nerve innervates the
buccinator muscle (*). The buccal nerve (>) communicates with a
branch of the facial nerve. The buccal nerve runs on the surface of
the buccinator muscle. FN, facial nerve; OO, orbicularis oris; PD,
parotid duct; MS, masseter muscle.
The Main Points of the Study
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The buccinator muscle in cats contrasts with humans because
in humans the muscle arises from the mandible and maxilla.
This muscles in the cats displays the following similarities to
human.
 1) innervated by the facial nerve
 2) supports the buccal muscle
 3) inserts into the modiolus (auditory nerve fiber)
 4) its bundles run antero-posteriorly
 5) posterior part of the muscle is located medially to the
masseter muscle
 6) parotid duct, facial nerve, artery, and vein run lateral to the
muscle.
 7) located deeper than other facial muscles
 8) buccal nerve runs on its surface.
ANY QUESTIONS?