Determination of tooth length with a standardized paralleling technique and calibrated radiographic measuring film.

A simple radiographic measuring method is presented. Fifty teeth to be extracted were radiographed by means of a standardized paralleling technique and a preprinted intraoral radiographic film. The measuring grid was conveyed to the film as a latent pattern by a stenciling process prior to the x-ray exposure. The distance between the measuring lines was adjusted in accordance with the image magnification. The length of the teeth was read directly on the completed radiograph. The extracted teeth were measured by means of a sliding caliper. A statistical analysis of the data indicated that the present method is more accurate than other clinical methods commonly used for determination of tooth lengths.