A full mouth radiographic series (FMX) consists of 20 images composed of periapical (16) and bitewing (4) projections. Periapical radiographs are intended to evaluate the periapical region of the tooth and surrounding bone. Therefore, it is essential to obtain the full length of the tooth and at least 2 mm of periapical bone. Bitewing radiographs record, on a single image, the crowns and coronal 1/3 of the interproximal bone of both arches. Bitewings are useful for detecting interproximal carious lesions, bone height, pulp chamber size and shape, pulp stones, and overhangs on interproximal restorations. It is therefore essential to position the image receptor and x-ray beam so that there is an equal distribution of both arches in the resulting radiographic image. Instrument Assembly: The Rinn XCP Instrument for a full mouth series (FMX) of x-rays consists of 3 parts: 1. 3 biteblocks for the anterior, posterior, and bitewing set-ups. 2. 3 Indicator rods for the anterior, posterior, and bitewing set-ups. 3. 2 Aiming rings for the anterior, posterior, and bitewing set-ups. a. The same aiming ring is used for the anterior and bitewing set-ups