Timing chain/ tensioner

The only way to determine the fault with the timing chain on your 2006 Nissan Altima would be to remove the timing cover and inspect the damage. It sounds like the tensioner or chain guides failed and now the chain has jumped time. Timing bells are similar to the serpentine drive belt but slightly different. Timing belts are tootled belts instead of the rib style you see on serpentine belts, the are generally designed to last longer.