The effect of altering the vertical dimension of occlusion on biting force.

The effect of altering the vertical dimension of occlusion (VDO) on the biting force was studied in six men and seven women. The biting force was registered with a newly designed gnathodynamometer that uses two strain gauges cemented on its surfaces and a Wheatstone bridge connected to a chart recorder. Biting force was measured for each subject at the following three positions of vertical dimension: position 1, VD < VDO; position 2, VD = VDO; and position 3, VD > VDO. The recorded force at these positions was statistically different for all of the subjects. All subjects exerted significantly greater biting force when VD > VDO Men exerted greater biting forces than women, but this difference was not statistically significant.