[Analysis of the denture dynamics in R.P.D.'s. 1. Methods for analyzing the denture dynamics of free-end-saddle]

Excess denture movement during function may cause to jeopardize the resorption of the residual ridges and the mechanical trauma on the abutments in the partially dentate mouth. A removable partial denture (R.P.D.'s) should be so constructed that the artificial teeth on the denture base will be stabilized in their spatial position by way of the compensatory support due to the remaining abutments and the residual ridges. In this pilot study, the ordinary denture movement, that is the denture dynamics in function of the free end saddle R.P.D.'s was measured in the test denture assembly. The denture dynamics was assessed in two ways: The displacement sensors revealed the vertical and the horizontal movement of the denture base during function. They were based on the field magnetic effect and with good lineality. Tiny accerelometer was attached to the denture base to detect the accerelation during function. Ordinary mastication was not interefered by both methods. The Author has already reported the palpation test for diagnosing the denture dynamics of the free end saddles in clinics. This method was discussed objectively against the accerelometry on fifty patients. Two methods have revealed the good coincidence with each other to detect the dynamics of the free end saddles.