An Orthopantomogram (OPG), also known as an "orthopantogram" or "panorex", is a panoramic scanning dental X-ray of the upper and lower jaw. Normal dental X-ray film is placed inside the mouth and covers only 3 to 4 teeth at a time. So some patients do get gag reflex while taking X-ray and to cover full mouth 10 such X-rays are needed. While in OPG film is outside the mouth and in single X-ray all the teeth as well as TM joint and maxillary sinus can be viewed. Comparatively patient is exposed to less radiation and it is less expensive.
What should I do if I chip a tooth or one is knocked out? If a tooth is chipped, clean the injured tooth with warm water. See your dentist as soon as possible and take any broken pieces; he or she may be able to bond them back onto the tooth. If tooth is knocked out, pick it up by the crown ( or top ), not the more delicate root, and rinse it off. Then place the tooth in milk, or wrap it in a damp cloth.