Study of the Spatial Accuracy of Jaw Models Depending on the Method of Obtaining an Impression and Its Material

Abstract

Methods for obtaining working and auxiliary dental impressions of patients have been revised in recent decades, which is associated with 3D scanning. At the same time, the policy of import substitution in dentistry is also developing quite actively, which is reflected in the introduction of domestic impression masses for analog prints into public health institutions.
 The aim of study. Reducing the number of complications of dental orthopedic treatment by optimizing the approach to choosing a method for obtaining a working anatomical impression.
 Methodology. Impressions of the mandible of 10 patients were obtained. 7 impressions were obtained from each patient using the most commonly used techniques, silicone impression materials and intraoral scanning. Further, jaw models of 4 types of plaster were made for each impression and scanned with an off-site dental scanner. With the help of a micrometer in the oral cavity, measurements of teeth 3.5, 4.4 and 4.2 were made according to the maximum vestibular-oral size of the clinical crown, which were taken as a standard. The reference size is compared with the dimensions obtained on digital models according to the selected parameters with an accuracy of up to thousandths of a millimeter. A statistical analysis of the data obtained was carried out.
 Results. The data obtained confirmed the manufacturer's claims about the accuracy of the impression masses. A slight decrease in the studied sizes was noted on the models obtained by intraoral scanning. Whereas on models obtained using silicone impressions, the dimensions, on the contrary, were slightly larger than the reference ones. A statistically significant difference was revealed when comparing models obtained using intraoral scanning and models obtained by laboratory scanning from analogues of jaws using silicone impressions. When comparing the data obtained with the standard, no critical differences were revealed.
 Conclusions. It is impossible to unequivocally assert the advantage of a digital or analog method of obtaining impressions in modern orthopedic dentistry. The method of obtaining an impression should be chosen depending on the indications for a particular type of treatment and clinical conditions.