Report on the determination of occlusal vertical dimension and centric relation using swallowing in edentulous patients.

When constructing a complete denture, the correct vertical dimension of occlusion (VDO) and centric relation (CR) can be difficult to determine. The aim of this study was to compare the swallowing technique used to determine the maxillomandibular relationship with a conventional technique. Fifteen edentulous patients were selected, each having a complete denture. The VDO and CR were assessed using acrylic base plates and a Boley gauge. First, the VDO was established by means of the vertical dimension of rest (VDR) and interocclusal rest space, and the CR was obtained by mandibular manipulation. Secondly, the VDO and the antero-posterior mandibular position were determined using swallowing. All measurements were repeated three times and the average was calculated. The results showed that (i). the VDO determined by means of the swallowing method was reproducible and significantly higher than the one established from the VDR (P < 0.01), and (ii). the swallowing position was located 2 mm anterior to CR (P < 0.01) and was moderately reproducible. This study suggests that swallowing can be used to determine the vertical position but no as a reference position in the sagittal plane.