Customize 'Save as type' shown in 'Save' dialog for a new file

[sajithpt]

Iam working on a Visual Studio extension that provides an option to open new files. New files are opened using
EnvDTE.ItemOperations.NewFile("General\SQL File", "Untitled1.sql", EnvDTE.Constants.vsViewKindTextView);

This file gets associated with MSSQL extension and shows the followig toolbar -

Is there a way to prevent getting this file associated with MSSQL extension (even when the file extension is .sql)? Is there a way to open new in memory files using a custom editor ?

Also, is there a way to customize filters shown in Save dialog when we save these in memory files ?

I want to add custom file types, for eg. My Files (*.myf) as 'Save As' type.