A Comparative Evaluation of Functional and Physiological Impression Techniques for Bilateral Distal Extension Removable Partial Dentures

Aim and objectives To compare the tissue displacement produced by the Hindels impression method, the selective pressure method, and the functional reline method in the anterior, middle, and posterior regions of bilateral distal extension ridges. Additionally, the study aims to identify the impression technique that provides optimal tissue recording for distal extension removable partial denture support. Materials and methods A patient with bilaterally missing mandibular posterior teeth was selected for the study. Five definitive casts were fabricated using each of the three impression techniques. Tissue displacement in the anterior, middle, and posterior regions was measured using a digital vernier caliper. The collected data were subjected to statistical analysis to evaluate intra-group and inter-group differences among the three techniques. Results Within each technique, tissue displacement values increased from the anterior to the posterior regions; however, these differences were not statistically significant (P > 0.05). Inter-group comparison demonstrated that both the Hindels and selective pressure methods produced significantly greater tissue displacement than the functional reline method across all regions (P < 0.001). No statistically significant difference was observed between the Hindels and selective pressure methods (P > 0.05). The overall mean tissue displacement was highest with the selective pressure method, followed closely by the Hindels method, and lowest with the functional reline method, indicating better functional tissue recording for distal extension removable partial denture support. Conclusion The Hindels and selective impression techniques demonstrated greater tissue displacement compared with the functional reline method, with the selective pressure technique showing the most favorable overall performance for distal extension removable partial dentures. These findings suggest that controlled functional recording of the edentulous ridge may promote favorable tissue recording, defined as capturing the supporting mucosa in a physiologically acceptable and controlled functional state. Such recording facilitates more balanced load distribution between the supporting mucosa and abutment teeth, thereby potentially enhancing denture stability.