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 fi rst 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 int ercuspation was clinically assessed in a sample of healthy adolescents and young adults undergoing a clinical trial which involved repeated occlusal a djustment. The T-scan(R) readings and the clinical assessments of the centr ic slide were obtained at baseline and at the third and fourth annual exami nation. There was an overall, but statistically not significant,decline in the contact time. The length of the centric slide did decrease significantl y. However, there was no systematic correlation between the two variables. They appear to describe different qualities of occlusion, and their validit y as a measure of 'goodness' of occlusion remains an unanswered question.