UTF-8 will be supported from TC10.1
When your database was created with an older TC Version it is not so easy to switch the database to UTF-8.
As far as I know is the offical way to setup a new Teamcenter environment with UTF-8 and transfer the existing data by a Multi-Site.
You're using Windows or Unix/Linux?
Starting with Teamcenter 11.2 supports the Unicode UTF-8 character set on Windows.
Did you finish a migration project where you switch from an non-UTF-8 DB to a UTF-8 Environment with MS SQL DB already?
Currently we setting up a new SQL DB with UTF-8 (TC11.4) and intend to transfer the data by Multi-Site Tools. If possible you may share some experiences...