Orthodontic costs vary greatly around the country. An average case fee is about $5000-$6000. Most offices will offer a variety of payment plans. An in house finance with no inâ¦terest typically will only finance the length of treatment with a 20-25% down payment. Average length of treatment is 18-24 months. Making your monthly payment $200-$300.
Under normal conditions, electrical activity is spontaneously generated by the SA node, the physiological pacemaker. This electrical impulse is propagated throughout the right atrium, and through Bachmann's bundle to the left atrium, stimulating the myocardium of the atria to contract. The conduction of the electrical impulse throughout the atria is seen on the ECG as the P wave. As the electrical activity is spreading throughout the atria, it travels via specialized pathways, known as internodal tracts, from the SA node to the AV node.
Figure 2. The conduction system of the heart. Left: Normal excitation originates in the sinoatrial (SA) node then propagates through both atria. The atrial depolarization spreads to the atrioventricular (AV) node, and passes through the bundle of His to the bundle branches/Purkinje fibers.