I don't mean to be blunt or dismissive, but the pressure in the veins/arteries has nothing to do with (a) the thickness/elasticity of the wall tissue, (b) the diameter of the arteries/veins, or (c) the number of (branches of) arteries/veins.
This can either be caused by a more prominent maxilla (upper jaw) or a retruded mandible (lower jaw further back than it should be). This causes a discrepancy in how all teeth contact, and can manifest as an increased overjet. An increased overjet can also be caused by a discrepancy in the number of teeth, or the length of the arch.
Answer   A backfire is caused by unburned fuel and air getting into a hot exhaust system where it ignites. Plugs have nothing to do with it. Some cars, when they ar â¦ e turned off, pass enough fuel and air, that isn't being burned in the now-turned-off cylinders to cause a backfire.