PERIODONTAL-LIGAMENT REACTION AND DISPLACEMENTS OF A MAXILLARY CENTRAL INCISOR SUBJECTED TO TRANSVERSE CROWN LOADING

A revised and extended version of a theoretical analysis appearing in a previous paper is employed here to study the displacements of a maxillary central incisor and accompanying periodontium reaction resulting from transverse crown loading. The theory is basically two-dimensional, but includes the effects of root tapering normal to the plane of the forces. For an incisor of specific dimensions, stress patterns normal to the root at the root-periodontium boundary are presented for several, clinically-interesting, tooth movement cases, and center-of-rotation locations are given for the entire range of transverse crown loadings. Results from present theory are compared with several, previously-published, theoretical and clinical efforts for the case of simple tipping; employing a more complex model than used in recent analytical studies, the theory herein yields closer agreement with clinical data than previously achieved.