###### Abstract
Consequently, real-world scenarios encompass a broader range of potential cases that may require the use of immobilization methods, with prescribed durations of 7-45 days, depending on the specific pathology. This approach remains fundamental for addressing various wrist and hand conditions, with the choice of material and method influenced by multiple patient-related and financial considerations. Recent literature discusses 3 DP-WHOs' outcomes from clinical practice for different types of pathologies by assessing their medical efficacy and users' feedback [8; 9; 10]. From an engineering perspective, the studies primarily focus on topics related to the acquisition of upper limb patient data [11], design considerations [12], and mechanical performance [13]. The main objectives are reducing the manufacturing time and automating the design process while ensuring that the orthoses meet their functional requirements. Achieving these objectives would make 3 DP-WHOs more accessible in medical facilities (3D Printing Point-of-Care) [14]. The first objective can be accomplished by printing the orthoses flat and subsequently thermoforming them to fit the patient's limb [15], thus saving time and material. Both objectives can be achieved by generating flat orthoses using a predefined template and input from a hand therapist measuring the patient's upper limb dimensions [16]. Other solutions for semi-automating the design process of 3 DP-WHOs in their functional or ready-to-use form have also been proposed in the literature [17]. However, only a limited number of papers have discussed strategies to reduce the printing time and costs [18; 19], although these are important factors related to the printability of customized WHOs, defined here as the capability to successfully 3D print orthoses that meet production efficiency criteria while also being functional and aesthetically pleasing. The design process of a customized WHO typically begins with a 3D scan of the patient's hand and forearm, followed by scan data processing and orthosis 3D modeling using specific software [11]. Thus, the virtual orthosis model is generated directly in its ready-to-use form corresponding to the anatomy of the patient's upper limb and then sent to the 3D printer for manufacturing [12]. 3 DP-WHOs often include open pockets for breathability and improved hygiene, enabling skin observation and reducing the weight of the orthosis. A critical design consideration, therefore, is the geometry of these ventilation pockets, which often, during the 3 DP process, require support structures to maintain their overhangs. These supports negatively impact the printing time, cost, and surface quality. Moreover, since 3 DP-WHOs are frequently reported to have thicknesses up to 4 mm [18; 20; 21], orienting them in a vertical position means printing thin and tall walls. These thin walls may lead to intra-layer filling defects or inter-layer adhesion defects, ultimately impacting their mechanical performance [13]. Conversely, building the orthoses horizontally can save time [18], but it affects the quality of the surfaces (resulting in a staircase effect) in contact with the patient's hand. Optimizing the build orientation in accordance with the process parameter values is, therefore, important. It typically involves dedicated slicers that virtually slice the orthoses in different orientations and assess the support structures' volume and placement, as well as printing time, through an iterative process. Unlike previous studies that primarily focus on orthoses general design and material selection, the current study investigated how different print orientations and slicer software settings influence the printing time associated with orthoses manufacturing, the first of which compares parameter settings across commonly used slicers.