Journal of Dental Research, Vol 80, 2021-2024, Copyright © 2001 by International & American Associations for Dental Research Online Journals
Movement of teeth adjacent to posterior bounded edentulous spaces
K. L. Gragg, D. A. Shugars, J. D. Bader, J. R. Elter and B. A. White
Department of Orthodontics, Center for Health Services Research, School of Dentistry, The University of North Carolina, Chapel Hill 27599-7450, USA. graggk@dentistry.unc.edu
Bounded edentulous spaces (BES)-a missing posterior tooth with intact
adjacent teeth-are thought to lead to arch collapse resulting from the
movement of adjacent teeth. To determine the rate of change in distance
between teeth adjacent to a BES, we examined three successive measurable
radiographs of 116 untreated posterior BES cases. The distance between the
teeth (DBT) adjacent to the space was measured, and change in DBT (delta
DBT) between pre-extraction and follow-up radiographs was calculated. We
used linear spline regression to construct models for tooth movement and to
identify factors associated with delta DBT. The mean delta DBT was < 1
mm during the first year post-extraction, and the DBT continued to decrease
at a successively slower rate each following year. Overall and for each
tooth type, the greatest rates of decrease in DBT were seen in the zero to
two-year period. In a multivariable model, time since extraction and tooth
type were significantly associated with delta DBT. These findings suggest
that movement of teeth adjacent to a posterior BES after the first two
years is usually gradual and minor within the time frame of this study.
