## 1 Introduction  
The innovation of computer-aided design/computer-aided manufacturing (CAD/CAM) technology has gained wide popularity in the dental field owing to its superior benefits. When compared to conventional procedures, the CAD/CAM technology facilitated the manufacturing of indirect restorations by promoting a faster, more convenient, and less hectic process. This technology incorporates both subtractive methods, like milling, and additive techniques, such as 3D printing, enhancing precision and ease in dental restoration production [1]. Various CAD/CAM milled resin composites have been launched in the market with promising mechanical and esthetic properties that allow them to be used in multiple clinical indications [2]. For a closer insight into their innovative microstructures, these materials mainly consist of a polymeric matrix with different types of dimethacrylate polymers augmented by high volumes of inorganic dispersed fillers, mainly glass fillers, that differ in size, shape, and composition [3]. The earliest CAD/CAM milled resin composite was manufactured by factory polymerization under optimized and standardized industrial conditions yielding satisfactory properties that were later improved by further polymerizations under high pressures and temperatures [4]. More recently, another competitive CAD/CAM manufacturing technique using 3D printing technology has been introduced [5; 6; 7]. This technique includes fabrication of the dental resin restorations by adding and compacting small fragments of the resin material together layer by layer [8]. When compared to the milling technique, the 3D printing method takes less time in the manufacturing process and results in less waste of the raw material [9]. Furthermore, the literature indicates that 3D-printed restorations exhibit superior mechanical properties but inferior physical properties compared to milling restorations, making them a cost-effective option for fabricating indirect dental restorations [10]. Orthodontic treatment using the fixed archive and bracket system is the most widely adopted approach globally [11]. As a result, the demand for orthodontic treatments in patients with indirect dental restorations has increased. However, achieving optimal and effective bond strength between orthodontic brackets and various restorative materials remains a significant challenge. Many studies [12; 13] have attributed these challenges to the inert nature of ceramics, underscoring the necessity of an additional surface treatment step during the bonding process. Various chemical and mechanical surface treatment methods have been explored to enhance bond strength, including hydrofluoric acid etching, sandblasting with or without silane application, and, more recently, the use of ceramic primers [14; 15]. Shear bond strength (SBS) testing is a widely used method in dentistry to evaluate the adhesive properties of dental materials to tooth structures or other restorative substrates. This test measures the maximum stress that a material can withstand before failure, specifically focusing on the bonding interface between the adhesive and the substrate under a shearing force. In dentistry, SBS tests are crucial for assessing the performance of dental adhesives, cements, and composite materials in clinical applications [16]. A strong bond between restorative materials and the tooth structure is essential for the longevity and durability of dental restorations such as crowns, veneers, bridges, and orthodontic brackets. By applying controlled force at a predetermined angle, SBS tests simulate the functional stresses restorations experience in the oral environment, including mastication and occlusal forces. SBS values help researchers and clinicians compare the effectiveness of different bonding agents, ensuring that materials can withstand the mechanical loads encountered in the mouth, thus guiding product development and clinical decision-making [17].