Abstract: The preferred embodiment of the apparatus comprises the combination of a fixture and ventilation tube, with the fixture including a mandrel that is engagingly received through the bore or lumen of the ventilation tube to define a distal tip projecting from the front face of the ventilation tube. A helical thread extends rearwardly from the distal tip of the fixture to the seating region of the ventilation tube along a conical surface formed by portions of both the fixture and ventilation tube.