Background or statement of the problem. Acrylic polymers, such as polymethyl methacrylate (PMMA), are widely used in the fabrication of removable dental prostheses due to their numerous advantages. These include adequate physical, mechanical, and aesthetic properties, low cost, easy fabrication, and biocompatibility. However, the lack of antimicrobial effects in denture base resins (DBRs) has garnered significant interest among dental researchers, particularly because PMMA lacks the ability to resist antimicrobial activity. Specifically, a recurring oral condition such as Candida-associated denture stomatitis (CADS) is difficult to eliminate because disease-causing yeast bacteria or fungi can penetrate the denture base materials. Furthermore, three-dimensional (3D) printing is rapidly emerging at the forefront of digital technology and permeating the dental profession, expanding treatment options for patients, such as fabricating dental prostheses. However, the surface properties of 3D printed materials have posed challenges in both general medicine and dentistry, primarily due to the potential for microbial adhesion to the material surface. To address this issue and mitigate the formation of biofilms on denture surfaces, previous studies have explored the incorporation of organic or inorganic antibacterial and antifungal agents into DBRs. Building upon this body of research, this study utilised phytochemical substances such as microencapsulated plant essential oils in 3D printing denture base materials. Objectives. The objectives of this project were: i. to incorporate microcapsules, containing biodegradable essential oil, into two 3D printed DBRs and investigate their effects on the physical and mechanical properties of the materials to ISO standards, ii. investigate the antimicrobial activity of the resulting materials, and to iii. investigate the cytotoxicity of the microcapsules. [...]