For many years, removable prostheses have been fabricated using conventional methods. However, with the advancement of CAD/CAM technologies, digital design and manufacturing of complete dentures have become more precise, rapid, and personalized options for patients [1]. Digital workflows reduce the number of clinical sessions and overall treatment time, enabling the creation of complex geometries through continuous layering. By minimizing workflow steps, the risk of errors decreases, thereby enhancing prosthesis quality [2].

Three-dimensional (3D) printing systems offer faster production and reduce labor costs by minimizing manual and time-consuming procedures, thus enabling more efficient and cost-effective manufacturing processes [3]. The subtractive CAD/CAM approach, which stores digital data, facilitates easy remanufacture of prostheses in cases of breakage or loss. Moreover, these digital records can later be utilized for implant planning and surgical guide preparation [4].

Complete dentures can be produced using CAD/CAM systems via two main approaches: computer numerical control (CNC) subtractive manufacturing and additive manufacturing (3D printing) [5]. Subtractive manufacturing involves obtaining restorations from prefabricated blocks using CNC machines. These machines employ milling tools to shape the material according to programmed commands. However, unused portions of disks or blocks generate material waste [6].

In contrast, additive manufacturing converts powder- or liquid-based materials into a solid object by building the desired shape layer by layer [7]. This method does not require abrasive milling tools and offers reduced production costs through lower material waste and energy consumption [8]. Digital workflows further reduce laboratory-induced errors [9]. In additive manufacturing, parameters such as print orientation, laser intensity, and speed substantially affect part accuracy, flexural strength, and surface roughness. Several studies have evaluated the impact of these parameters on the mechanical and surface properties of printed objects [10].

Among additive technologies, Digital Light Processing (DLP) and Liquid Crystal Display (LCD) are the most widely used in dentistry. DLP polymerizes liquid resin via a projector and a digital micromirror device (DMD), curing an entire layer in a single exposure, repeated layer by layer until the object is complete [11]. LCD technology is similar, curing each layer simultaneously; however, light passes through an LCD panel rather than being projected [12]. A key distinction between DLP and LCD is light intensity [13], which is critical for photopolymerization, determining the degree of curing and printing speed [14]. Only about 10 % of light in LCD systems passes through the panel, with the remaining 90 % absorbed. Light-sensitive resins designed for DLP devices can be used in LCD printers by adjusting exposure time or initiator concentration. LCD technology offers advantages such as lower cost and high resolution [14,15].

The primary objective of this study was to comprehensively evaluate the internal surfaces of complete dentures fabricated using Digital Light Processing (DLP) and Liquid Crystal Display (LCD) technologies. A precise quantitative digital analysis was performed to assess the extent of distortion associated with each manufacturing approach. In addition, key fabrication parameters—including denture base weight, residual material, production time, and resin consumption—were systematically measured to provide an integrated assessment of the efficiency and accuracy of these additive manufacturing methods.

The null hypotheses were formulated as follows: Denture bases fabricated using DLP and LCD technologies, across various build orientations, would not exhibit statistically significant differences in (a) geometric accuracy, (b) base weight, (c) residual material, (d) production time, or (e) resin consumption, either among themselves or when compared with the reference design. Furthermore, no statistically significant interaction effect between the manufacturing technology and build orientation is expected. Any observed differences would be attributed to random variation rather than systematic factors.