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.
Causes. Mitral regurgitation may be caused by: 1  Mitral valve prolapseâAbnormal closure of the valve with protrusion of a leaflet tip backward into the left atrium, causing it to leak. 2  Infections that cause scarring of the heart valve, such as rheumatic fever or bacterial endocarditis.