Also when you need to make database configuration changes its a good idea to log into the SCCM server using your SCCM service account (which you should have set up prior to installing SCCM) and make all changes under that account so that if ownership does change at least the ownership will be designated to the SCCM service account and not your personal user account. This will ensure that your user-specific domain account is not accidentally given ownership of some SCCM-critical database related item. Plus (while it may not work every time) there’s a good chance that even if the SCCM service account somehow gets ownership of the item you change there’s it *could* continue to function just fine (as this account should have been set up by you as a local admin on your SCCM Server and also as a SysAdmin on your SQL Server).
Here's a couple of useful SQL queries to help troubleshoot this issue (run from SQL Server Management Studio):
-- Check Database ownership:
-- Change a Database owner to 'SA'
EXEC sp_changedbowner 'sa'