Objectives: The aim of this randomised controlled clinical trial is to evaluate surgical accuracy and efficiency of computer-assisted jaw reconstruction using 3D-printed patient-specific titanium surgical plates versus conventional plates. Hypothesis to be tested: The investigators hypothesize that compared to conventional surgical plates, 3D-printed patient-specific surgical plates improve surgical accuracy and efficiency of computer assisted jaw reconstruction. Design and subjects: This is an open-label, prospective, double-arm, and single-centre randomised controlled clinical trial. Patients with maxillary or mandibular neoplastic, inflammatory and congenital diseases who require immediate or secondary reconstructive surgery will be invited to participate in the study. Study instruments: 3D-printed patient-specific titanium surgical plates and conventional plates. Main Outcome Measures: The primary endpoint is the accuracy of reconstruction. The secondary endpoints include the accuracy of osteotomy, reconstruction time, total operative time, intraoperative blood loss, length of post-operative hospital stay, and postoperative adverse events. Data analysis: The accuracy parameters, reconstruction time, total operative time, intraoperative blood loss, length of post-operative hospital stay will be presented as mean values with standard deviations. The post-operative adverse events will be calculated and presented as frequency with standard deviation. Expected results: This randomised control trial will prove improved accuracy and efficiency of reconstruction using 3D printed patient-specific titanium surgical plates. This study is expected to provide high-level evidence to push forward the popularity of using 3D medical printing technology in surgical field.