ANTERIOR MAXILLARY GROUP. IBS' 



ANTERIOR MAXILLARY GROUP. 



In the broad sense this group occupies the anterior half of the 

 skull, certain of the muscles extending further backwards; it 

 consists of the followins: muscles : — 



Zygomaticus. 



Buccinator. 



Orbicularis oris. 



Levator labii superioris alaeque 



Nasalis longus. [nasi. 



Dilatator naris lateralis. 



Dilatator naris transversus. 

 Dilatator naris inferioris. 

 Dilatator naris superioris. 

 Depressor labii superioris. 

 Levator labii inferioris. 

 Depressor labii inferioris. 



ZYGOMATICUS. 



{Z ygomatico-lahialis.) 



(PL. XL 9.) 



A ribbon-shaped muscle, very pale and small, situated on the 

 side of the face, its fibres extending forwards. 



Attachments. — It arises from the fascia of the masseter, near 

 the anterior aspect of the maxillary spine, being blended with 

 the panniculus, and is inserted near the angle of the mouth, its 

 fibres blending with the buccinator. 



Action. — It retracts the angle of the mouth. 



BUCCINATOR. 



(Alveolo-Iabialls.) 



(Pl. II. 9'. Fig. 70. i.) 



Situated on the side of the face, covering the diastema and' 

 molar teeth, this muscle is flat and thin, and consists of two 

 layers, sometimes described as separate muscks. 



Attoxhments. — The internal layer arises, under the masseter, 

 from the alveolar tuberosity, and alveoli of the molar teeth of 

 both jaws, and blends with the orbicularis oris. The external 

 layer exists only anteriorly, and is peuniform, its fibres being 

 inserted along the interdental spaces. 



Relations. — This muscle is related superiorly with the molar 

 glands, postero-externally with the masseter, and internally with, 

 the buccal membrane. 



