An evaluation of xeroradiographs and radiographs in length determination in endodontics.

Twelve block sections of mandibles containing incisors, canines, premolars, and molars were dissected from human cadavers (total, 26 teeth). Endodontic access was achieved, and a No. 10 k-type endodontic file was inserted to a point approximately 1 to 2 mm short of the radiographic apex. By securing the mandible and Rinn instrument with plaster mounts, exposures were made from identical angles and film and jaw placement remained constant in both techniques. Conventional film images were recorded on Kodak Ultraspeed film with six to eight impulses. Xeroradiographic images were recorded with four to five impulses. Radiographs and xeroradiographs were evaluated with the use of light from a masked viewbox. A magnifying glass was used to evaluate visualization of the following entities: the root apex; the periodontal ligament; the trabecular pattern; and the measuring instruments. The images were examined and categorized by three examiners, who used the following scores: 3, optimal for diagnostic information; 2, adequate for diagnostic information; 1, poor but providing diagnostic information; and 0, unacceptably poor. In all categories examined, the information provided by xeroradiographs was significantly greater than that provided by conventional radiographs (p less than .05). In terms of diagnostic value and lower patient dose, xeroradiographs are preferred to conventional radiographs.