This research addresses the development of a formalized approach to dental material selection (DMS) in manufacturing removable complete dentures (RDC). Three types of commercially available polymethyl methacrylate (PMMA) grades, processed by an identical Digital Light Processing (DLP) 3D printer, were compared. In this way, a combination of mechanical, tribological, technological, microbiological, and economic factors was assessed. The material indices were calculated to compare dental materials for a set of functional parameters related to feedstock cost. However, this did not solve the problem of simultaneous consideration of all the material indices, including their significance. The developed DMS procedure employs the extended VIKOR method, based on the analysis of interval quantitative estimations, which allowed the carrying out of a fully fledged analysis of alternatives. The proposed approach has the potential to enhance the efficiency of prosthetic treatment by optimizing the DMS procedure, taking into consideration the prosthesis design and its production route.

BACKGROUND: Despite numerous studies on the quality of life of patients with dental issues, no specific questionnaire is available for patients with total loss of teeth. AIM: This study aimed to establish the level of validation and automation effectiveness of the OHIP-20 DG questionnaire for assessing life quality satisfaction of patients who received fully removable plate prostheses. MATERIAL AND METHODS: The questionnaire was validated by analyzing the psychometric parameters of 50 patients based on the results of the questionnaire survey (17 women, 33 men; aged 4287 years). RESULTS: The reliability (self-consistency) of the OHIP-20 DG questionnaire was adequate based on the following values: Cronbachs alpha coefficient, 0.780.81; individual functional scales, 0.660.73; convergent validity, 0.1290.503; divergent validity, 0.00040.504; and discrimination, 0.400.89. The scaling success rate of symptomatic subscales ranged from 91.67% to 100%. CONCLUSION: The OHIP-20 questionnaire is suitable as a measuring tool for assessing the life quality satisfaction of patients who received fully removable plate prostheses. The OHIP-20-DG application for mobile devices reduces the amount of routine operations in collecting data and processing examination results; thus, it can be recommended for clinical work in dental prosthetics.

BACKGROUND: The most affordable and economical types of prosthetics are modern designs of completely removable plate prostheses. However, in most cases, they do not meet the patients expectation. OHIP-20-DG, which is a specific quality-of-life (QOL) questionnaire, is a valid tool that allows diagnosis of patients response to treatment, assessment of the effectiveness of prosthetics, and better understanding of patients complaints and dissatisfaction. AIM: To create a sensitive specific questionnaire of dental QOL indicators for patients with total loss of teeth based on the well-known valid questionnaire Dental health impact profile OHIP-49 and to examine patients quality of life before and after prosthetic application. MATERIAL AND METHODS: The QOL of 50 patients with total loss of teeth (17 women and 33 men, aged 4287 years), who received removable dentures with an acrylic polymer base and set teeth, was examined. QOL monitoring was performed using the proposed specific questionnaire OHIP-20 DG. RESULTS: The integral QOL index increased to 47.42% after prosthetic application and to 78.43% following adaptation to the prosthesis after 6 months. Age and gender differences in the QOL level of patients were determined. According to the domains physical discomfort, psychological discomfort, and social maladjustment, men and women assessed their satisfaction with their physical, psychological, emotional, and social functioning differently. Gender differences in patients aged 55 years in the psychological discomfort and social maladjustment domains were significant (p=0.065) when compared with those of patients aged 55 years (p=0.115). CONCLUSION: Results of monitoring the QOL of patients with total loss of teeth before, during the stages, and after application of prosthetics with fully removable dentures, obtained using the OHIP-20 DG questionnaire, allow us to reliably assess the effectiveness of prosthetics.

BACKGROUND: In the rehabilitation of patients with complete loss of teeth, an important aspect is the study of their quality of life (QL) as an indicator reflecting the effectiveness of treatment. AIM: Use latent variables and control their magnitude to control the development or suppression of symptoms in patients. MATERIAL AND METHODS: Within the framework of the modern theory of latent variables, the study examined the QL of patients with complete loss of teeth at various stages of dental orthopedic treatment. RESULTS: The average relative error of the forward and reverse conversion of the polytomic score indicators, i.e., latent variables, was 3.69%, which indicated a very high accuracy of measurements of latent variables. The QL estimates obtained by different methods were in good agreement with each other, and the Pearson correlation coefficients were 0.991, 0.999, and 0.982 before and after prosthetics. The characteristic curves of the questionnaire items were close to the experimental score indicators (p 0.05). The parameters of the latent variables at various stages of treatment were calculated using the KolmogorovSmirnov criterion, which showed that their distributions were normal, and the medians moves in different directions, which corresponded to an increase in QoL during treatment and adaptation. The interpretation of latent variables is proposed: i is the resistance (reserve level) of the body of the i-th patient before prosthetics or the effectiveness of treatment and adaptation after prosthetics; j presents the severity and intensity of pathogenic factors in the development of the j-th symptom, and Pij is the probability of the removal of the j-th symptom in the i-th patient. CONCLUSION: It has been established that by identifying and measuring latent variables, as well as controlling their magnitude, we can control the level of development or suppression of symptoms in patients.

BACKGROUND: The study researched the structure of the OHIP-20 DG questionnaire, which was compiled from the questions of the validated international special questionnaire OHIP-49, to assess the patients quality of life depending on their mouths organs and tissue with the help of сategorical principal component analysis. PURPOSE OF THE STUDY: Reduce the original set of variables to an uncorrelated variables that carry the bulk of the information contained in the original set. MATERIAL AND METHODS: To determine the connections between the scales of the quality of life (QoL) questionnaire OHIP-20 DG and to assess the factor validity of the latter, data reduction with generalization procedure was conducted by the method of nonlinear principal component using the CatPCA algorithm. RESULTS: All scores from 0 to 4 were smoothed by a second-degree polynomial spline with three internal knots and ranking as a discretization method. To determine the number of necessary and sufficient components, Cattells scree plot and broken stick criteria were used. Calculations were performed using the IBM SPSS Statistics package (version 20), graphical constructions in the KyPlot (version 6.0), and PAST (version 4.06) packages. CONCLUSION: The factor structure of the questionnaire was explored using CatPCA algorithm of nonlinear principal component analysis. The analysis confirmed the factor validity of the OHIP-20 DG questionnaire, but found two weak structural elements that are not related to the QoL, but most likely have a connection with the psychosocial aspects of patients health. Comparison of the questionnaires initial scores with their quantification values revealed the nonlinearity of patients perception of most of the questionnaire items. Which allows for a broader interpretation of the patterns of patients perception of QoL and further improvement of the questionnaire.