The dawn of rapid maxillary expansion.

The first report of lateral maxillary expansion by separation of the maxilla, written by Angell and published in 1860, was discredited. Applying our present-day knowledge of the technique to the original documents indicates that the case history agrees in general with current observations. The arguments mounted against Angell, especially by McQuillen, may be dismissed as irrelevant and Angell's thesis is upheld. In addition, good reason exists to accept three further "firsts" in this unprecedented work: (1) The significance of the first permanent molars in occlusal development, (2) the use of a double-action jackscrew, and (3) the use of a retention plate.