## 1 Introduction  
Jaw defects can be caused by tumors, trauma, or infectious diseases. Oral squamous cell carcinoma (SCC) of the mandibular gingiva and ameloblastoma are included for the purpose of resection of the mandible. Generally, when these destructive lesions occur, we can perform a marginal mandibullectomy or segmental mandibullectomy. The mandible is resected segmentally or marginally and then reconstructed with complex reconstruction using various free flaps. In the case of segmental mandibulectomy, reconstruction of the mandible also requires rehabilitation of dentition for occlusion and linguistic ability. Therefore, the reconstruction of bone and soft tissue through free flap transfer is regarded as the best treatment to restore function [1]. In the case of a patient with a severely atrophic mandible or who has undergone a marginal mandibulectomy and requires implant treatment, the inadequacy of the bony height and volume of soft tissue may be a challenge [2]. Vascularized or non-vascularized bone grafts, distraction osteogenesis, and guided bone regeneration have been used to install implants for rehabilitation [3]. Jaw defects can be reconstructed using microvascular composite free flaps with the scapula, radial forearm, fibula, and deep circumflex iliac artery(DCIA) flap [4]. The surgeon chooses the donor site considering various factors, such as the size, location, and condition [5]. A DCIA flap has been used for the reconstruction of the jaw defect due to the natural shape of the arch, sufficient width and height, and the possibility of obtaining bicortical bone with good-quality cancellous bone [5]. In particular, it is useful for the reconstruction of severe bone defects such as segmental mandiublectomy and hemimandibulectomy [6]. Donor-site morbidity is another important factor to consider when choosing donor sites [5]. However, DCIA is known to have various minor complications, including gait disturbance, hernia, and fracture. In particular, large bony defects at the ilum area cause weakening of the supporting tissue, leading to complications such as gait disturbance, iliac fracture, and hernia [6]. The use of a bicortical DCIA flap when large amounts of bone segments must be harvested can sometimes cause abnormal hip contour, hernia, a tendency to exhibit severe bleeding, and gait disturbances [7]. Monocortical DCIA flaps can reduce donor-site morbidity for the harvesting of large amounts of bone segments [7]. In addition, the monocortical DCIA flap has the advantage of minimizing gait disturbances, preserving the contour of the hip, and speeding up the patient's postoperative recovery [7]. Iliac bone fracture is not a common complication after DCIA flap harvesting, because the ASIS (anterior superior iliac spine) can include the harvested flap. However, when including the ASIS, the patient may lose the hip contour and suffer from gait disturbance. Generally, iliac bone fractures can be treated by open reduction and internal fixation. Orthopedic implants need to possess important properties, such as biocompatibility, relevant mechanical properties, high corrosion and wear resistance, and osseointegration, to ensure safe and effective use [8]. A variety of implant materials have been used according to requirements in various fields of medicine, such as metals, alloys, ceramics, and polymers [8]. Among them, titanium and titanium alloys are widely used as orthopedic implant materials due to their mechanical and biological properties [9; 10; 11; 12; 13]. Moreover, a porous titanium structure allows bone ingrowth into the pores to gain stable osseointegration between the implant and surrounding bone [14; 15]. Recently, computer-aided and 3D-printed guided surgery has become popular. Thus, iliac bone fractures can be treated with this modality. The introduction of computer-aided design (CAD) and computer-aided manufacturing (CAM) systems has led to several advantages for both clinicians and patients, and commercial software offers reliable methods to simulate and perform the procedure [16].