On the nose develop four muscles, knowledge in top, the pyramidal one; in bottom, the myrtiforme; on the sides, the transverse and the dilator one of the nostrils.
The Pyramidal muscle
The pyramidal muscle is a small muscle located at the same time on the back of the nose and in the eyebrow area, immediately below the frontal, with which it seems to be continued, hence the name of pillars of the frontal that one sometimes gives to the two pyramidal ones.
This muscle occurs, partly below, on the side cartilages of the nose; partly, on the lower edge and the edge clean bones of the intern nose . From there, its beams go vertically in top towards the inter-eyebrow area, or the beams of the frontal succeed in addition . On the points where they come into contact, the two muscles are penetrated reciprocally, as extremely well established by Sappey, but without merging. They finish one and the other with the deep face of the teguments.
The two pyramidal ones are juxtaposed and joined together seemingly on the line of centers. A cellulous space, generally extremely narrow, separates it from the right-sided one on the left side.
The pyramidal one is innerved by the facial one (under-orbital nets of its branch of higher junction).
The two pyramidal ones, fascinatingly turn and are not fixed on the nose, pull at bottom the skin of the eyebrow area, which is folded in transverse wrinkles. They are, as is seen, antagonists of the frontal muscles, which attract the skin at the top. This antagonism, already formulated by Sappey in 1837, was clearly shown later by the electrophysiological experiments of Duchenne (of Boulogne).
Macalister saw the pyramidal completion distinct from the frontal muscle.
Transverse muscle of the nose
The transverse of the nose is a triangular muscle , in front aponevrotic, fleshy behind , lying on the cartilaginous portion of the wing of the nose
It fits by its base on the back of the nose, using an aponevrosis which merges, on the line of centers, with that on the opposite side. The fleshy beams which make following this aponevrosis direct in bottom, outwards and behind towards the furrow of the wing of the nose. They are divided in two groups : the anterior beams stick to the deep face of the teguments of the area ; the posterior beams, are followed with the external beams of the myrtiforme.
By its deep face, the transverse rests directly on the wing of the nose. Its surface face answers the teguments in most of its extent it is not which its most external part; has only it is covered by the elevator muscles with the wing with the nose and the upper lip.
As for the precedent.
The former beams or peauciers of the transverse muscle attract towards the back of the nose the teguments on which they fit. They determine thus, in the area of the wing of the nose, the formation of vertical wrinkles. The posterior beams, contracting at the same time as the myrtiforme, flatten made nose and thus decrease the width of the opening of the nostrils.
The Myrtiforme muscle is a small flattened and radiated muscle, located below the nostrils, immediately behind the upper lip.
It fits, below, on the upper maxilla, on the level of the small myrtiforme cavity and the projection of the canine tooth. Its free, going then in top towards the opening of the nasal fossae, deviates with the manner of one ventilated and are divided in three groups the internal fibers come to stick to the under-partition; the average fibers are fixed at the posterior edge of the cartilage of the wing of the nose the external fibers circumvent this cartilage, by following a curve its concavity directed in top and inside, and are continued, as we already mentioned above, with the posterior beams of the transverse.
The Myrtiforme muscle rests directly on the skeleton of the face.
It is covered, ahead, by the gingival mucous membrane, the half-orbicular superior and by the various beams which come to finish, its level has, in the upper lip.
As for precedent.
While meeting with the posterior beams of the transverse muscle, the external beams of the myrtiforme constitute on the external side of the nostril a half-sphincter kind whose contractions cause to narrow this opening. The internal beams and the average beams attract in bottom the lower part of the nose, hence the name of depressor of the wing of the nose, under which one indicates sometimes the myrtiforme- Moreover, the average beams, similar to their obliqueness, carry the wing of the nose in bottom and inside; they thus bring it closer to the line of centers and decrease by as much you transverse diameter of the nostril. On the whole, the myrtiforme lowers made nose and narrows your nostrils.
Dilator muscle of the nostrils
Santorini described under this name a muscular blade, extremely thin and very atrophied in the man, laid down on the lower part of the wing of the nose.
Its fibers stick, behind, at the same time on the posterior edge of the cartilage of the wing of the nose and on the corresponding part of the upper maxilla. From there, they go ahead and in bottom, while following a curve with lower concavity, and come to finish with the deep face of the skin which recovers the external edge of the nostril.
The dilating muscle of the nostrils answers on the one hand the teguments, on the other hand with the cartilage of the wing of the nose. Its development is very variable on certain subjects, it is very visible and of a relatively easy dissection on others, on the contrary, it is not perceptible with the naked eye and the use of the microscope is necessary to note the existence of muscle fibers in the area which it occupies.
As for the precedent.
The dilating one, taking its point fixes behind, attracts the wing of the nose outwards and widens the nostrils thus transversely. It is, as it is seen, antagonist of the two preceding muscles.