The User roles of the application are managed by Mendix Studio Pro design-time and will result into records in the System.Userrole entity. It's not possible to create or delete records in that table, you can only administrate them in the Security pop-up of the application (see screenshot below).
If you deleted a user role and recreate it, you have to reselect the module roles associated with it.
Maybe you can reverse merge the change from the repository if you committed it as a change to the teamserver!?
Hopefully this answered your question, otherwise, please elaborate a bit more on what you try to achieve.