Dentrix Enterprise automatically assigns the first case created as the default treatment plan case, but you can change which case is the default for the patient.
To set the default treatment plan case
In Treatment Planner, in the Treatment Plan Case Setup section on the Navigation panel, right-click the case that you want to be the default treatment plan for the patient, and then click Set Case as Patient's Default Treatment Plan.
Note: This option is available only if the case is not already the default treatment plan for the patient.