Perineural spread of squamous cell carcinomas in the orofacial region
predominantly involves the trigeminal and facial nerves. Central sprea
d, particularly along the trigeminal nerve, produces sensory impairmen
t and involvement of other divisions through invasion of the gasserian
ganglion, as illustrated in these case reports. Early diagnosis and m
edical referral is important because central invasion has a poor progn
osis.