No. Wolf teeth are not always present. If a horse has wolf teeth they appear just behind the second premolars in the upper jaw and very rarely in the lower jaw. A horse may have as few as one wolf tooth, or as many as four.
It is recommended to have these teeth pulled before a horse is 2 years old, as the root system is not fully developed. If your horse is expected to wear a bit they can cause pain or interfere with the bit if they are left intact.