I dont know what you meant explain further.
Anyone who writes any application that uses RDBMS can easily prevent any orphan record from existing simply by create a Foreign Key constraint.
If any parent/child relationship exists, then orphan can be prevented by using FK.
If "orphan session" really existed & needed to be resolved, then Oracle would have simply added FK to prevent it from happening long before V10, V11, or v12 of the software.
Your imagination greatly exceeds your total knowledge of Oracle RDBMS!