Assessment of occlusal stability by measuring contact time and centric slide

The aim of the present study was to evaluate two different methods for the assessment of the positional stability of occlusion. The time taken from first contact on closure to full intercuspation was measured by the T-scan(R), and the length of the slide between centric relation (CR) and maximum intercuspation was clinically assessed in a sample of healthy adolescents and young adults undergoing a clinical trial which involved repeated occlusal adjustment. The T-scan(R) readings and the clinical assessments of the centric slide were obtained at baseline and at the third and fourth annual examination. There was an overall, but statistically not significant, decline in the contact time. The length of the centric slide did decrease significantly. However, there was no systematic correlation between the two variables. They appear to describe different qualities of occlusion, and their validity as a measure of 'goodness' of occlusion remains an unanswered question.