On Comparing Two Different Tray-Holding Techniques for Edentulous Maxillary Impressions.

PURPOSE This study compared tissue three-dimensional (3D) displacements during the material setting phase of two maxillary impression tray-holding techniques: clinician manual pressure and patient occlusal pressure. MATERIALS AND METHODS The resultant two maxillary casts for each of 10 edentulous patients were compared using an optical 3D measurement system. RESULTS The junction between the hard and soft palates acted like a rotation center during impression making. The vertical displacements were significantly lower and posteriorly set when the impression was taken with the patient's occlusion, in contrast to being located at the anterior two-thirds during the manual impression technique. CONCLUSION Use of patient's occlusion as a tray-holding technique may be preferred during the material setting phase of maxillary impressions.