Erodible device comprising surfactant for modifying {TAIL ~ the rate} of {HEAD ~ erosion} of the device 
Erodible device comprising surfactant for modifying { TAIL ~ the rate } of { HEAD ~ erosion } of the device
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH