Preparation of irreversible hydrocolloids to improve retention of complete dentures

Abstract

Precise reproduction of anatomical-morphological details of dentures support on working models presupposes adequate application of modern impression materials and casting procedure, as well as minimal dimensional change of these materials. experimental and clinical research is connected to irreversible hydrocolloides and the objective was to examine the most suitable consistency of the alginate as the impression mass for the purpose of improving retention of complete dentures. This research included 35 completely toothless patients, most of who had already had complete dentures, 40-80 years of age and of both sexes. Static adhesion was measured with acrylate plates made of adequate corresponding and various models depending on consistency of the irreversible hydrocolloides. Each model was cut into three parts, the cuts obtained were mutually compared, and computerized graphic charts of each section were made. The results of the research show that there is a greater retention force in the acrylate plates obtained on models casted on an anatomical impression base taken with irreversible hydrocolloides of solid consistency. Analysis of the results shows such quality of impressed tissues that they are practically slightly displaced by the impressions regardless of the consistency of the material impressed. In conclusion it is pointed out that the preparation of irreversible hydrocolloides must be carried out by strictly obeying the powder-water weight ratios. The sections of the models obtained by irreversible hydrocolloides of various consistencies, that is by applying different pressures, point to minimal displacement of tissues and great differences in the retention force in favour of the compressive impression.