EVALUATION OF THE EFFECTIVENESS OF DIGITAL AND ANALOG TECHNOLOGIES IN THE MANUFACTURE OF COMPLETE REMOVABLE DENTURES

ISSN: 2582-4686 SJIF 2021-3.261,SJIF 20222.889, 2024-6.875 ResearchBib IF: 9.948 / 2024 VOLUME-5, ISSUE-11 1137 EVALUATION OF THE EFFECTIVENESS OF DIGITAL AND ANALOG TECHNOLOGIES IN THE MANUFACTURE OF COMPLETE REMOVABLE DENTURES Khabilov Nigman Lukmanovich Tashkent State Medical University https://orcid.org/0000-0002-1404-507X e-mail: [email protected] Annotation Modern orthopedic dentistry is undergoing a stage of digital transformation, affecting all aspects of diagnostics, modeling and manufacturing of orthopedic structures. Special attention is paid to improving the methods of manufacturing complete removable dentures, aimed at improving accuracy, reducing treatment time and improving patient adaptation. The purpose of this work is to conduct a systematic analysis and comparison of modern technologies for manufacturing complete removable prostheses, including analog, milled and 3D-printed methods, from the standpoint of accuracy, biocompatibility, aesthetics and clinical effectiveness. Keywords: complete removable dentures, CAD/CAM, 3D printing, milling, adaptation, digital prosthetics, biocompatibility. INTRODUCTION Modern orthopedic dentistry is currently undergoing an intensive stage of digital transformation, which significantly affects the technologies used for the fabrication of complete removable dentures. The problem of complete secondary edentulism remains one of the most urgent issues in clinical practice, since total loss of teeth leads to pronounced disorders of the dentoalveolar system’s functions—mastication, speech, swallowing and breathing—as well as to deformation of the lower third of the face, deterioration of facial aesthetics and a decline in the patient’s psychoemotional stability According to the World Health Organization, the prevalence of complete edentulism in individuals over 60 years of age ranges from 15 to 25%, and among patients older than 75 years exceeds 40%. At the same time, a significant proportion of such patients cannot receive fixed prosthodontic constructions for medical or economic reasons, which makes complete removable dentures the most accessible and in-demand method of restoring the functions of the dentoalveolar system.The traditional technology for manufacturing removable dentures, based on manual tooth arrangement and heat polymerization of an acrylic base, remains widely used, but has several disadvantages. In recent years, digital CAD/CAM (Computer-Aided Design / ComputerAided Manufacturing) technologies and additive manufacturing (3D printing) have been introduced into orthopedic practice. These methods provide high accuracy of fit, dimensional stability and predictable esthetic outcomes.The use of digital protocols makes it possible to design the denture in a virtual environment, minimize the number of clinical appointments, and create constructions with high accuracy of adaptation and optimal occlusion.In this regard, three main approaches to the fabrication of complete removable dentures are forming in modern dentistry:1. Analog methods, based on conventional laboratory technology of pressing polymethyl methacrylate.2. Monolithic milled constructions, fabricated from solid blocks of acrylic plastic or polymers using subtractive processing on CNC milling machines.3. Segmented milled or 3D-printed constructions, created ISSN: 2582-4686 SJIF 2021-3.261,SJIF 20222.889, 2024-6.875 ResearchBib IF: 9.948 / 2024 VOLUME-5, ISSUE-11 1138 using CAD modeling with subsequent assembly of the base and tooth segment from separate elements.Each of these technologies has its own advantages and limitations related to accuracy, biocompatibility, cost, fabrication time and patient adaptation.A number of studies (Goodacre et al., 2021; Al Helal et al., 2022; Bidra et al., 2023) have shown that digital dentures demonstrate less shrinkage and a more uniform distribution of masticatory pressure compared to traditional dentures, which contributes to improved adaptation and a reduced rate of inflammatory complications of the denture-bearing mucosa. At the same time, questions remain unresolved concerning the clinical and laboratory rationale for choosing a particular technology in different clinical conditions, evaluation of denture longevity and stability, and the economic effectiveness of these technologies. Aim of the study To conduct a clinical and laboratory evaluation of complete removable dentures fabricated using different techniques, and to determine the optimal technology that provides high accuracy, durability and comfort for patients with complete edentulism. Materials and methods The study was carried out at the Department of Orthopedic Dentistry of the Tashkent State Dental University. The work was conducted over four years, from 2021 to 2025. Examination and orthopedic treatment of patients with complete secondary edentulism were performed in the clinical facilities of the department and in the university dental laboratory, equipped with modern devices for both digital and conventional prosthodontics.The study included 90 patients (43 men and 47 women) aged 45 to 75 years who sought orthopedic care due to complete loss of teeth in both jaws. Inclusion criteria were: absence of teeth in one or both jaws (diagnosis K08.1), satisfactory general health, absence of contraindications to orthopedic treatment, and signed informed consent to participate in the study.Exclusion criteria were: severe systemic diseases in the decompensation stage, oncological and infectious diseases, severe occlusal abnormalities, as well as psychoneurological disorders that hinder cooperation with the doctor.Study design Patients were divided into three groups of 30 people each, depending on the method used to fabricate the complete removable denture:Group 1 – monolithic milled dentures fabricated by subtractive processing (CAD/CAM milling from solid PMMA blocks).Group 2 – segmented milled dentures, where the base and tooth segment were fabricated separately with subsequent digital assembly in a virtual environment.Group 3 – analog dentures fabricated using the traditional method of pressing acrylic resin (heat-cured polymerization).Patient allocation was carried out using random sampling with equal distribution by sex and age, which made it possible to avoid systematic bias during comparisons. Clinical stages of the study At the initial examination, medical history was collected, patients were photographed, and the condition of the denture-bearing mucosa was recorded. The following parameters were assessed: inter-alveolar height, retention potential, condition of the mobile mucosa, and the prominence of alveolar ridges.To assess baseline functional parameters, the following methods were used:- Hamburg test (Ahlers M.O., 2000) to determine symmetry of mandibular movements; - Palpation of masticatory muscles and TMJ to detect tenderness and joint sounds (clicking); - Registration of the centric relation of the jaws using both conventional and digital techniques with the aid of bite rims and the electronic axiograph KaVo ARCUSdigma II. Methods of denture fabrication For the analog group (Group 3), the traditional technology according to the standard five-stage protocol was used: anatomical and functional impressions, registration of jaw relations, tooth ISSN: 2582-4686 SJIF 2021-3.261,SJIF 20222.889, 2024-6.875 ResearchBib IF: 9.948 / 2024 VOLUME-5, ISSUE-11 1139 arrangement, try-in, and final pressing of the base.Monolithic milled dentures (Group 1) were designed in the Exocad DentalCAD software package. The base and tooth segment were then milled from a solid block of acrylic PMMA. The use of monolithic milling eliminated polymerization shrinkage and deformation typical of pressed constructions.Segmented milled dentures (Group 2) were created using a combined technology: the base and tooth segment were modeled separately, which allowed more precise correction of inter-tooth contacts and tooth axis inclinations. After verification of the virtual model, the elements were joined using a thermoactivated resin.In all groups, the following parameters were evaluated: Accuracy of base adaptation (by digital scanning); Occlusal relationships (T-Scan III); Stability of denture fixation; Presence of complaints and duration of the adaptation period.Condition of the mucosa at 1, 3, 6 and 12 months.Laboratory and instrumental methods.To assess the accuracy of adaptation and base parameters, the following were used: 3D comparison of models in Exocad and Geomagic Control X software;Radiovisiography to analyze base contacts with the alveolar ridge;Scanning of impressions and dentures using the Medit T500 scanner with an accuracy of 7 µm;Analysis of masticatory load distribution using the T-Scan III computerized system (Tekscan, USA).To study the microstructure of material surfaces, scanning electron microscopy (SEM) was performed, and flexural strength was evaluated using an Instron 5982 testing machine with loads up to 3 kN.Statistical analysis Data processing was carried out using IBM SPSS Statistics v26 and Microsoft Excel 2019. Descriptive statistics methods were applied; the Mann–Whitney and Kruskal–Wallis tests were used for intergroup comparisons, and Pearson correlation analysis was used to identify associations between fit accuracy and adaptation time. Differences were considered statistically significant at p<0.05. Results A comprehensive evaluation of clinical-functional and laboratory parameters of complete removable dentures fabricated using different techniques was performed. The analysis included assessment of base adaptation accuracy, masticatory load distribution, adaptation period, condition of the denture-bearing mucosa and patients’ subjective satisfaction.Analysis of the accuracy of denture base adaptation.Comparative analysis of 3D model superimposition data showed that the smallest deviations between the digital prototype and the finished denture were observed in the group of monolithic milled constructions. The mean discrepancy was 0.048 ± 0.007 mm, whereas it was 0.072 ± 0.011 mm for segmented milled dentures and 0.182 ± 0.025 mm for analog dentures (p<0.001).Computer analysis with the T-Scan III system demonstrated a more uniform distribution of masticatory load in patients using monolithic milled dentures. In this group, the percentage ratio of pressure between the right and left sides was 51.2% / 48.8%, which is close to physiological norms.In the group with segmented milled dentures, a slight shift of load was noted (53.5% / 46.5%), while in the analog group there was marked asymmetry (57.8% / 42.2%), indicating the presence of premature contacts and uneven base adaptation.The mean occlusal time (time to reach stable occlusal contact) in the monolithic milled group was 0.21 ± 0.05 s, whereas in the analog group it was 0.36 ± 0.08 s, indicating better functional adaptation with the digital protocol.Evaluation of clinical retention and stability.One month after denture insertion, satisfactory retention was observed in 93% of patients with monolithic milled dentures, 87% with segmented milled dentures, and only 68% with analog constructions.After six months of use, the indicators ISSN: 2582-4686 SJIF 2021-3.261,SJIF 20222.889, 2024-6.875 ResearchBib IF: 9.948 / 2024 VOLUME-5, ISSUE-11 1140 decreased slightly in the digital groups (by 3–4%), whereas in users of traditional dentures, the need for adjustment or rebasing was noted in 26% of patients. This difference is associated with the surface characteristics of the base. Milled dentures have a smooth, dense structure that hinders microbial adhesion, whereas pressed acrylics are characterized by microporosity and residual monomer that contribute to tissue irritation. Subjective assessment of comfort and adaptation According to patient questionnaires using the modified OHIP-14 scale, the satisfaction level after 1 month of denture use was:Monolithic milled dentures – 82.6 ± 4.1 points;Segmented milled dentures – 78.3 ± 4.8 points;Analog dentures – 63.7 ± 5.2 points (p<0.001). After 6 months, scores in the digital groups remained stable, whereas patients with analog dentures showed a gradual decrease in comfort due to base deformation and the need for repeated adjustments.Laboratory assessment of mechanical properties Flexural strength testing showed that milled dentures withstood loads up to 2.85 ± 0.18 kN, while analog constructions failed at 2.03 ± 0.22 kN. SEM surface analysis revealed an absence of microcracks and air inclusions in milled bases, which correlated with their greater durability. Discussion Comparative analysis of the clinical and laboratory parameters of different methods for fabricating complete removable dentures revealed clear differences in accuracy, stability and adaptive capacity, which is consistent with trends reported in contemporary literature. The obtained data confirm that digital CAD/CAM technologies and subtractive milling provide higher accuracy of adaptation and reproducibility of occlusal relationships compared to traditional analog methods. In the present study, monolithic milled dentures showed the best performance across all functional criteria. Minimal discrepancies in base adaptation (0.048 mm) indicate the precision of digital manufacturing, which eliminates the polymerization and thermal deformations inherent to conventional acrylic pressing. This is supported by foreign studies reporting that CAD/CAM dentures are characterized by stable geometry and high reproducibility of parameters during longterm wear (Goodacre et al., 2021; Al Helal et al., 2022).Particular importance is attached to the uniformity of masticatory load distribution as recorded by T-Scan III. For monolithic milled constructions, the distribution was closest to physiological (51.2% / 48.8%), indicating harmonious occlusion and reduced risk of overloading the denture-bearing mucosa. Similar results were obtained in studies by Kerstein R.B. (2019), where it was noted that digital occlusal adjustment allows balanced contacts to be achieved at an early stage of adaptation.The functional advantages of digital technologies were also observed in terms of clinical stability and subjective comfort. After six months of use, milled constructions maintained retention in 90% of cases, whereas analog dentures required adjustment in almost one third of patients. These differences can be explained by the absence of residual monomer, lower base porosity and a smoother surface in milled dentures, which reduce microbial adhesion and the probability of denture stomatitis. According to literature data, the incidence of inflammatory complications with traditional dentures reaches 30–35%, while for digital dentures it does not exceed 10% (Mangano et al., 2020; Bidra et al., 2023).Questionnaire results using the OHIP-14 scale confirmed faster adaptation to digital dentures. Already one month after insertion, patients reported a marked improvement in oral health-related quality of life. Similar conclusions were drawn in the study by Fenlon et al. (2018), where subjective satisfaction directly correlated with the accuracy of adaptation and a reduction in complaints about mucosal ISSN: 2582-4686 SJIF 2021-3.261,SJIF 20222.889, 2024-6.875 ResearchBib IF: 9.948 / 2024 VOLUME-5, ISSUE-11 1141 irritation.Mechanical testing showed that milled dentures have significantly higher flexural strength and resistance to microcracks. This is consistent with in vitro studies in which CAD/CAM acrylics demonstrated a 25–40% increase in strength due to the absence of internal stresses and a homogeneous material structure (Saponaro et al., 2022).At the same time, it should be noted that segmented milling, despite somewhat lower accuracy parameters, remains clinically relevant when individual correction of tooth-arch form and esthetic parameters is required. This makes the technique a compromise solution between cost-effectiveness and functional efficiency. Conclusion The study demonstrated that the choice of technology for fabricating complete removable dentures has a significant impact on their clinical and laboratory characteristics and on the effectiveness of orthopedic treatment. The obtained results convincingly confirm that the use of digital CAD/CAM technologies ensures higher accuracy in reproducing the anatomical structures of the denturebearing area, stability of occlusal relationships and quality of base adaptation to the mucosa.Monolithic milled constructions showed the smallest deviations from the virtual model, high stability during mastication and a minimal number of complications related to the denturebearing mucosa.Segmented milling, despite somewhat greater variability in accuracy parameters, made it possible to achieve optimal esthetic and functional outcomes due to the possibility of individualized correction of tooth-arch form and intermaxillary relationships. These constructions provided a high degree of patient adaptation and comfort while preserving the advantages of digital modeling.At the same time, traditional analog methods based on acrylic pressing demonstrated limited accuracy of adaptation, greater shrinkage and a tendency toward base deformation, which negatively affected denture stability and patient satisfaction. According to questionnaire data, users of digital constructions reported a more pronounced improvement in oral health-related quality of life, reflecting not only functional but also psychological advantages of digital dentures.The use of modern diagnostic systems such as electronic axiography and T-Scan III computerized occlusal analysis made it possible to increase the accuracy of centric relation registration, improve the balance of masticatory loads and shorten the adaptation period. Mechanical testing confirmed that milled dentures possess higher strength and durability compared to analog dentures, which is due to the homogeneous structure of the material and the absence of polymerization deformations. ETHICAL STATEMENT AND CONSENT TO PARTICIPATION (original English block, kept)The study was conducted in accordance with the local ethical committee. Sources of fundingThe authors state that there is no external funding for the study. Availability of data and materialsAll data generated or analysed during this study are included in this published article. Authors’ contributionsAll authors contributed to the design and interpretation of the study and to further drafts. All authors read and approved the final manuscript. Ethics approval and consent to participateAll applicable international, national and/or institutional ethical guidelines have been followed. Consent for publicationNot applicable. Publisher’s NoteJournal of Integrative dentistry and maxillofacial surgery remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. REFERENCES ISSN: 2582-4686 SJIF 2021-3.261,SJIF 20222.889, 2024-6.875 ResearchBib IF: 9.948 / 2024 VOLUME-5, ISSUE-11 1142 1. Хабилов Н. Л. и др. госпитал ортопедик стоматология кафедраси йил давомида нашр этилган тезислар хисоботи. – Conferences, 2023. 1. Sharipov S. S., Mirxoshimova M. F., Ermatova F. R. " INTEGRATIV STOMATOLOGIK TA'LIM"(IST): MUSTAQIL VA DUAL TA’LIMNI BIRLASHTIRUVCHI YONDASHUV //Конференции. – 2025. – Т. 1. – №. – С. 376379. 2. Xabilov, N. L. "ЧАККА-ПАСТКИ ЖАҒ БЎҒИМИ КАСАЛЛИКЛИГИ БИЛАН ОҒРИГАН БЕМОРЛАРНИ ДАВОЛАШ КЎРСАТГИЧЛАРИ." Journal of new century innovations 18.2 (2022): 148-168.Нормуродова, Р. З., Дадабаева, М. У., Мирхошимова, М. Ф., Халиметов, Ж. З., & Толмасов, С. Д. (2021). ЛЕЧЕБНО-ПРОФИЛАКТИЧЕСКИЕ МЕРОПРИЯТИЯ БОЛЬНЫХ ЗАБОЛЕВАНИЯМИ ПАРОДОНТА ПРИ САХАРНОМ ДИАБЕТЕ 2 ТИПА. ПРОБЛЕМЫ И ПЕРСПЕКТИВЫ РАЗВИТИЯ НАУКИ И ОБРАЗОВАНИЯ В ХХI ВЕКЕ, 271-281. 3. Дадабаева, М., Зиядуллаева, Н., Мирхошимова, М., & Абдуллаев, С. (2020). ДЕТИ В ПРИАРАЛЬЕ И ПОВЫШЕНИЕ СТОМАТОЛОГИЧЕСКОЙ КУЛЬТУРЫ ВЗРОСЛЫХ. Стоматология, 1(1 (78)), 15-19. 4. Xabilov, N. L., Xabilov, B. N., Sharipov, S. S., Muxiddinova, F. G., Mirxoshimova, M. F., & Nabiyev, K. A. (2024). STOMATOLOGIYADA O ‘SIMLIKKA ASOSLANGAN KOMPLEKS VOSITALARNI ISHLAB CHIQISH. Journal of new century innovations, 66(1), 203-209. 5. Хабилов, Н. Л., Хабилов, Б. Н., Шарипов, С. С., Мирхошимова, М. Ф., & Набиев, К. А. (2024). ХИМИЧЕСКИЕ ОЖОГИ СЛИЗИСТОЙ ОБОЛОЧКИ ПОЛОСТИ РТА. Journal of new century innovations, 66(1), 210-216. 6. Хабилов, Н. Л., Хабилов, Б. Н., Шарипов, С. С., Мирхошимова, М. Ф., Набиев, К. А., & Рашидов, Р. А. (2024). БИОПЛЁНКАЛАР ЁРДАМИДА ЯРАЛАРНИНГ ТУЗАЛИШИ. Journal of new century innovations, 66(1), 195-202. 7. Xabilov, N. L., Muxitdinnova, F. G., Mirxoshimova, M. F., Nabiyev, K. A., Salamova Sh, S., Sharipov, S. S., & Sultanova, N. (2024, November). TO’LIQ TISHSIZLIKDA CAD/CAM TEXNOLOGIYALARINING ROLI: ZAMONAVIY YONDASHUVLAR VA IMKONIYATLAR. In Конференции (pp. 254-257).