A Mathematical Method to Calculate the Vertical Dimension for Fully Edentulous Malaysians Patients

Abstract

Recording of vertical dimension for patients who seek oral and occlusal rehabilitation is one of the main steps of the treatment. Many methods were proposed for the profession yet none can be used solely to determine the vertical dimension. Teaching and assessment of vertical dimensions for undergraduates should be monitored by extra simple-use techniques. The aim of this study was to find a simple, reliable, fast method to record and assess the vertical dimension by dental students and practitioners. Data were collected from 115 young volunteers from MAHSA University with natural healthy occlusion. Their age range was 18-25 years. The distances from endocanthion to commissure of the mouth (IC-MC), nasion to gnathion at occlusion (NA-GN occ), and at rest (NA-GN rest) were measured by 3 examiners. The records were correlated using the Pearson correlation method at (ρ<.01, 2-tailed), and a linear regression model was calculated. In addition, the ratios between the two measurements were calculated to find the Golden number. The results revealed the presence of a significant linear relationship between the vertical dimension, measured from the nasion to gnathion at occlusion and rest positions with IC-MC distance (r =0.90, and r =0.89 at ρ<.01 respectively). On the other hand, regression analysis yielded two linear formulae that can be used to predict the vertical dimension at occlusion and rest in edentulous patients. In conclusion, a new technique was presented to assess the vertical dimension as a tailored method for Malaysian patients.