Comparison between skeletal, and facial measurements of vertical dimension in edentulous patients

Background: The use of dots on the nose, and chin as markers for measuring occlusal vertical dimension is common in complete denture construction. Therefore, it is important to evaluate the accuracy of facial measurements while assessing occlusal vertical dimension in edentulous patients. Materials and methods: The study was carried out on 28 edentulous patients. Occlusion rims were constructed, a central bearing-screw attached to the lower occlusion rim, and a central-bearing plate was attached to the upper occlusion rim. Then the occlusal vertical dimension was increased at predetermined amount (3, and 5 mm) by counting the number of flutes of the central bearing screw, and the corresponding facial measurements recorded by using a caliper device to the nearest 0.1 mm. Results: It was found that 3 mm increase in skeletal height corresponded to mean facial increase of 1.81 mm and ranged between 1-3.5 mm, while 5 mm increase in skeletal height, correspond to mean facial increase of 3.56 mm and ranged between 2.1-5.3 mm. Conclusions: Alteration of vertical skeletal relationships is corresponding with less alteration in facial movement between reference marks above, and below the mouth. This suggests that depending on facial marks when assessing occlusal vertical dimension is not very accurate.