Evaluation of Correlation between Vertical Dimension of Occlusion (VDO) and Facial Proportions

Establishment of VDO (Vertical Dimension of Occlusion) is one of the most important factors in prosthetic rehabilitation of edentulous patients. There is no universally accepted method in VDO determination for edentulous patients.The aim of this study was to evaluate the relationship between VDO and facial proportions.In this descriptive analytical cross-sectional study, sixty four 0-0 year old dental students with class I occlusion were selected. The distances between subnasal to submental areas in the maximum intercuspation, external corner of the eye to corner of the mouth, first one third eyebrows to the ala of the nose and outer corner of one eye to the inner corner of the other eye were measured. Two methods of measurement were used:) electronic digital caliber to measure the indices on the face.) AutoCAD software to measure the indices on the subjects’ digital photos. Pearson and linear regressions tests were used for statistical analysis.The results showed a significant correlation between VDO and measured indices (p <0.00). There was no significant difference between the two methods. A minimal correlation was detected between VDO and the outer corner of one eye- the inner corner of the other eye dimension. A significant correlation was found between VDO and the external corner of the eye- corner of the mouth distance.It is concluded that some guidelines can be used for VDO determination. The vertical distance between the external corners of the eye to the corner of the mouth was the most reliable guidelines.