Tortoise neck and head scratched by own shell

by Veronique Koken
(Oldsmar, FL, USA)

Hello, and thanks if you can answer this question about my red-footed tortoise, Yuri:

The top of its head and its neck seem to get scratched and now developing open sores and scabs due to what looks like its shell edge. Should we sand the shell down at the edge or what should we do? I have applied some antibiotic cream to the wounds but the tortoise seems to continue scratching them, so to no avail.
Please advise...
Veronique