24 THE POCKET ANATOMY 



Dilatator naris: Anterior slip. Cartilage of ala(p) inner 



border of integument of ala(p). Posterior slip. Nasal notch 

 of superior maxilla(F) inner border of integument of ala(F) 

 (Facial). [Dilates anterior nares.] 



SUPERIOR MAXILLARY REGION. 



Levator labii superioris : superior maxilla and malar above 

 infra-orbital foramen (F) orbicularis oris(F) (Facial). [Raises 

 upper lip.] 



Levator anguli oris: canine fossa of superior maxilla, 

 beneath infra-orbital foramen(p) angle of mouth(p) (Facial). 

 [Raises angle of mouth, as in smiling.] 



Zygomaticus major: malar bone in front of zygoma(p) 

 angle of mouth(F) (Facial). [Raises angle of mouth.] 



Zygomaticus minor : malar bone near maxillary suture(p) 

 angle of mouth(p) (Facial). [Raises angle of mouth.] 



INFERIOR MAXILLARY REGION. 



Levator labii inferioris, vel levator menti : incisor fossa of 

 inferior maxilla(F) integument of chin(p) (Facial). [Raises 

 skin of chin.] 



Depressor labii inferioris, vel quadratus menti : external 

 oblique line of inferior maxilla from symphysis to mental 

 foramen(p) orbicularis oris(p) (Facial). [Draws down lower 

 lip, everting it.] 



Depressor anguli oris, vel triangularis menti : external 

 oblique line of inferior maxilla(p) angle of mouth (F) (Facial). 

 [Depresses angle of mouth, as in crying.] 



INTER-MAXILLARY REGION. 



Orbicularis oris : sphincter of mouth. The labial part is free 

 from attachment to bone, and forms red part of lips. The outer 

 or facial part is connected with the muscles which converge 

 to the angles of the mouth, and is attached in the upper lip 

 to septum nasi and incisive fossa of superior maxilla, and in 

 the lower lip to canine fossa of inferior maxilla(p) (Facial). 

 [Closes oral fissure, producing radiating wrinkles.] 



Buccinator: external surfaces of alveolar processes of 

 superior and inferior maxillae, as far forwards as ist molar ; 

 pterygo-maxillary ligament(p) angle of mouth where fibres 

 decussate(p) (Facial). [Closes mouth, also prevents food col- 

 lecting between teeth and lips ; maintains tone of cheeks, as 

 in whistling. 



