Disposable Mouth Props Medium (Child) White 48/Bag. Assists in keeping the patient's mouth open during dental procedures. Best for children and sedated patients. Odorless and tasteless. EXTND Disposable Mouth Props help keep the patient's mouth open during routine dental procedures. They are most suitable for children and patients who are sedated or unable to keep their mouths open for an extended period.The mouth props are disposable, eliminating the need for manual cleanup.