Odontogenic tissue that is avascular non-mineralized matrix that is deposited by preameloblast and ameloblasts that are excluded from the matrix. [ PSPUB:0000170 http://purl.obolibrary.org/obo/go/references/0000034 http://dx.plos.org/10.1371/journal.pone.0051070 VSAO:0000066 ]