From The Collaborative International Dictionary of English v.0.48 :
Buccal \Buc"cal\, a. [L. bucca cheek: cf. F. buccal.] (Anat.)
Of or pertaining to the mouth or cheeks.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
buccal
adj 1: of or relating to or toward the cheek
2: lying within the mouth; "a buccal gland"
3: oriented toward the inside of the cheek; "the buccal aspect
of the gum"