Radioactive particle inter-tissue implantation is a kind of brachytherapy, which is a minimally invasive way to administer multiple encapsulated radionuclide particles with certain specifications and activity directly into the tumor tissues through the applicator for high-dose irradiation treatment. It has the advantages of high precision, small trauma and sure efficacy. Since 1998, this most advanced foreign minimally invasive tumor treatment technology has been introduced into China, firstly for the treatment of prostate cancer, and then extended to the treatment of lung cancer, pancreatic cancer, liver cancer, bone metastasis cancer, recurrent rectal cancer, etc. Around 2000, it was used for the treatment of oral and maxillofacial-head and neck malignant tumors. In the following cases, surgery combined with radioactive particle implantation or radioactive particle implantation alone should be considered as the priority treatment for oral and maxillofacial-head and neck malignant tumors: 1) adenoid cystic carcinoma (parotid, submandibular, sublingual and intraoral glands), 2) malignant tumors of tongue root, floor of mouth, oropharynx, tonsils and parapharynx, 3) low-grade malignant tumors of parotid gland requiring preservation of facial nerve, 4) maxillary malignant tumors, 5) maxillary malignant tumors, and 6) malignant tumors of the bone. malignant tumor of mandible, 5, advanced malignant tumor of oral and maxillofacial region, 6, recurrence of head and neck tumor after surgery or radiotherapy, 7, metastatic cancer of head and neck lymph nodes, 8, unable to tolerate radical surgery or even external radiotherapy due to systemic condition.