Facial Paralysis fy 



The supra-maxillary nerve takes its name from its position upon 

 the lower jaw, and must not be confused with the superior maxillary 

 nerve, the large sensory trunk which emerges from the infra-orbital 

 foramen (p. 62). The supra-maxillary branches supply the platysma 

 and the small muscles of expression connected with the lower lip and 

 chin. 



The infra-maxillary nerve is so called because it lies below the 

 jaw ; it supplies the platysma and joins with the superficial cervical 

 nerve (v. p. 145). It must 

 not be confused with the 

 inferior maxillary nerve 



(P- 63). 



When the facial 

 nerve is paralysed, as 



in fracture of the petrous 

 bone, all the muscles of 

 expression on that side 

 of the face are paralysed, 

 and the wrinkles and 

 furrows of the skin are 

 smoothed out. 



The forehead on that 

 side can be thrown into 

 neither horizontal (occi- 

 pito-frontalis) nor trans- 

 verse (corrugator super- 

 cilii) creases, and the 

 patient cannot close his 



eye (orbicularis palpe- Branches of facUl nerve :-i, to occip. front ; a ,post*uri- 

 brarum). I hllS even cular ; 3^ temporal brs. ; 4, malar brs. ; 5, infra-orb. 



il ; 7, supra-maxillary ; " ' " 



during sleep the cornea 



remains exposed ; and 



so, in such a case, to prevent inflammation, the lids had better be kept 



approximated by strips of adhesive plaster. But when the paralysis 



is of cerebral origin the orbicularis escapes, owing to the existence of 



certain commissural fibres. 



The tensor tarsi the muscle which holds the puncta lachrymalia 

 against the eye-ballbeing powerless, the tears fall over on to the cheek, 

 and, as the orbicularis can no longer wash them inwards, the eye-ball 

 becomes dry and irritable, though this may not occur if the patient 

 keeps it clean and moist by dragging down the lid with his finger. 

 The mouth, which is naturally balanced in the middle line, is now 

 dragged by the unopposed muscles over to the sound side of the 

 median line, as is particularly noticed when the patient laughs, for then 

 the muscles contract with greater energy. 



On account of paralysis of the orbicularis oris, the saliva dribbles 



F2 



