The Smiler at Alton Towers was shut on Saturday after the guide wheels hit riders in the face and shoulder as it went up an incline.
A spokeswoman for the park said they had been working with designers to review and replace elements connected to part of the ride affected.
She said the £18m ride opened at 10:30 GMT on Thursday after safety checks.
The ride opened in May and includes a drop of 30m (98ft) and 14 loops.
Full Story: BBC