Root resorption extremes resulting from clinical RME.

An assessment has been made of the area of root surface resorption on extracted RME anchor premolar teeth from eighteen patients held in fixed retention for periods varying between 14 and 52 weeks. The areas of resorption present were extensive but did not increase significantly over the time interval studied. By comparison, the proportion of repair tissue in the defects became greater with the more prolonged retention periods. The topographic findings suggest that strong relapse forces are probably dissipated after 3 months of retention. This investigation showed no correlation between the period of RME, the length of retention, and the total area of resorption affecting the anchor teeth. These findings are discussed in relation to retention following RME.