Movement of abutments by removable partial denture frameworks with a hemimaxillectomy obturator

A laboratory experiment was conducted to measure the amount of movement in each of two directions on each of seven teeth, induced by three common designs of retainer, under both splinted and unsplinted conditions. An analysis of variance on a four-way, completely crossed, fixed-effects model showed significant main effects for design, splintedness, and teeth involved. Also of significance were the interactions between the factors of splintedness and teeth and between design and splintedness. Most of the variability in tooth movement was due to differences among the seven teeth (49.3 per cent of variance) and to the interaction of splintedness and teeth (20.2 per cent of variance).