ABSTRACT
@#With the development of computer-aided surgery and rapid prototyping via 3D printing technology, digital surgery has rapidly advanced in clinical practice, especially in the field of oral and maxillofacial surgery. 3D printing technology has been applied to the functional restoration and reconstruction of the jawbone. Before surgery, a 3D digital model is constructed through software to plan the scope of the osteotomy, shape the bone graft and plan the placement of the implant. Additionally, 3D models of personalized surgical instrument guides are printed prior to surgery. With these 3D-printed models and guides, accurate excision of the jaw tumor, accurate placement of the grafted bone and precise placement of implants can be achieved during surgery. Postoperative evaluation of accuracy and function shows that 3D printing technology can aid in achieving the biomechanical goals of simultaneous implant placement in jaw reconstruction, and in combination with dental implant restoration, the technology can improve patients' postoperative occlusal and masticatory functions. Nevertheless, 3D printing technology still has limitations, such as time-consuming preparation before surgery. In the future, further development of 3D printing technology, optimization of surgical plans, and alternative biological materials are needed. Based on domestic and foreign literature and our research results, we have reviewed the process and clinical application prospects of jaw reconstruction via 3D printing technology to provide a reference for oral and maxillofacial surgeons.
ABSTRACT
Objective@# To investigate the clinical characteristics of salivary gland tumors and their pathological types.@*Methods@#Data from 2 456 patients with salivary gland tumors diagnosed between January 1973 and December 2018 at Sun Yat-sen Memorial Hospital of Sun Yat-sen University were collected, and their gender, age and tumor pathological type, location, and benign and malignant composition ratios were retrospectively analyzed.@*Results@#Over the 46-year study period, 2 456 patients with salivary gland tumors were treated; 41.9% were female, and 58.1% were male. The peak incidence was found among the 40 to 60 years of age group, in which 593 (24.1%) patients had malignant tumors and 1 863 (75.9%) had benign tumors. The ratio of benign and malignant tumors was 3.1∶1. The top two most common benign tumors were pleomorphic adenoma (58.7%) and Warthin tumors (33.6%). The top two most common malignant tumors were mucoepidermoid carcinoma (27.7%) and adenoid cystic carcinoma (26.1%). The most common sites of benign pleomorphic adenomas were the parotid glands, palate, and submandibular glands. Mucinous epidermoid carcinomas in malignant tumors were common in the parotid glands and small salivary glands. The incidence of salivary gland tumors in this group has increased each year, and this group accounted for 53.3% of the total cases over the past 10 years.@*Conclusion@#The number of patients with salivary gland tumors is increasing each year. The total incidence of salivary gland tumors is higher in men than in women. Large salivary gland tumors are mainly benign tumors, and small salivary gland tumors are more common. Polymorphic adenomas, Warthin tumors, and mucoepidermoid carcinomas are the most common tumor types; patients 40~60 years old are most likely to have benign salivary glands and have a high incidence of malignant tumors.
ABSTRACT
Objective @#To analyze the value of virtual surgical planning in the surgical treatment of osteoradionecrosis of the mandible and to provide a reference for clinical practice.@*.Methods @#From September 2017 to June 2018, 13 patients with mandibular osteoradionecrosis were evaluated preoperatively using the 3D virtual surgery software CMF Proplan 2.0. The surgical guide was designed and 3D printed. Bone resection, fibula shaping and bone graft localization were completed during the operation. In some cases, implants were implanted at the same time, and denture restoration was completed 3 to 6 months after surgery. Patients’ general information, perioperative data, and efficacy evaluation were analyzed.@*Results@#All patients underwent surgery successfully. The survival rate of the free fibula musculocutaneous flap was 100% (13/13), and one patient had complications (partial necrosis at the edge of the flap). The follow-up period was 7 to 15 months, and the median time was 10 months. All patients achieved a healing effect. The number of cases with an increase in mouth opening ≥ 1 cm, 0.5 cm ≤ mouth opening increase < 1 cm, and mouth opening increase < 0.5 cm were 5, 6, and 2, respectively. An imaging examination showed that 12 patients had good bone healing, and 1 patient did not completely heal 7 months after operation. The denture restoration was 92.3% (12/13), of which 3 cases were implanted and repaired at the same time. The average chewing efficiency was 56.11% ± 7.12% (42.03%-67.83%).@*Conclusion@#Virtual surgical planning is an effective method for the surgical treatment of mandibular osteoradionecrosis, which can reduce the risk of surgery and more effectively perform mandibular shape and function repair.