David,
one reason is that they come out that easily. I had one in after surgery and it lasted exactly half a day before I puked it up...... The other disadvantage is that the diameter is quite small which is ok for water an low viscosity fluids.

M


Partial glossectomy (25%) anterior tongue. 4/6/07/. IMRT start @5/24/07 (3x) Erbitux start/end@ 5/24/07. IMRT wider field (30x) start 6/5/07. Weekly cisplatin (2x30mg/m2), then weekly carbo- (5x180mg/m2). End of Tx 19 July 07.