Surgical operation is the main treatment of oral and maxillofacial tumors.Dysphagia is a common postoperative complication.Swal-lowing disorder can not only lead to mis-aspiration,malnutrition,aspiration pneumonia and other serious consequences,but also may cause psychological problems and social communication barriers,affecting the quality of life of the patients.At present,there is no systematic evalua-tion and rehabilitation management plan for the problem of swallowing disorder after oral and maxillofacial tumor surgery in China.Combining the characteristics of postoperative swallowing disorder in patients with oral and maxillofacial tumors,summarizing the clinical experience of ex-perts in the field of tumor and rehabilitation,reviewing and summarizing relevant literature at home and abroad,and through joint discussion and modification,a group of national experts reached this consensus including the core contents of the screening of swallowing disorders,the phased assessment of prognosis and complications,and the implementation plan of comprehensive management such as nutrition management,respiratory management,swallowing function recovery,psychology and nursing during rehabilitation treatment,in order to improve the evalua-tion and rehabilitation of swallowing disorder after oral and maxillofacial tumor surgery in clinic.

Cryoablation therapy with explicit anti-tumor mechanisms and histopathological manifestations has a long history.A large number of clinical practice has shown that cryoablation therapy is safe and effective,making it an ideal tumor treatment method in theory.Previously,its efficacy and clinical application were constrained by the limitations of refrigerants and refrigeration equipment.With the development of the new generation of cryoablation equipment represented by argon helium knives,significant progress has been made in refrigeration efficien-cy,ablation range,and precise temperature measurement,greatly promoting the progression of tumor cryoablation technology.This consensus systematically summarizes the mechanism of cryoablation technology,indications for oral mucosal melanoma(OMM)cryotherapy,clinical treatment process,adverse reactions and management,cryotherapy combination therapy,etc.,aiming to provide reference for carrying out the standardized cryoablation therapy of OMM.

The biological clock(also known as the circadian rhythm)is the fundamental reliance for all organisms on Earth to adapt and survive in the Earth's rotation environment.Circadian rhythm is the most basic regulatory mechanism of life activities,and plays a key role in maintaining normal physiological and biochemical homeostasis,disease occurrence and treatment.Recent studies have shown that the biologi-cal clock plays an important role in the development of oral tissues and in the occurrence and treatment of oral diseases.Since there is cur-rently no guiding literature on the research methods of biological clock in stomatology,researchers mainly conduct research based on pub-lished references,which has led to controversy about the research methods of biological clock in stomatology,and there are many confusions about how to rationally apply the research methods of circadia rhythms.In view of this,this expert consensus summarizes the characteristics of the biological clock and analyzes the shortcomings of the current biological clock research in stomatology,and organizes relevant experts to summarize and recommend 10 principles as a reference for the rational implementation of the biological clock in stomatology research.

Neck dissection(ND)is one of the main treatment methods for oral and maxillofacial malignancies.Although ND type is in con-stant improvement,but intraoperative peal-pull-push injury of the accessory nerve,muscle,muscle membrane,fascia and ligament induced shoulder syndrome(SS)is still a common postoperative complication,combined with the influence of radiochemotherapy,not only can cause pain,stiffness,numbness,limited dysfunction of shoulder neck and arm,but also may have serious impact on patient's life quality and phys-ical and mental health.At present,there is still a lack of a systematic evaluation and rehabilitation management program for postoperative SS of oral and maxillofacial malignant tumors.Based on the previous clinical practice and the current available evidence,refer to the relevant lit-erature at home and abroad,the experts in the field of maxillofacial tumor surgery and rehabilitation were invited to discuss,modify and reach a consenusus on the etiology,assessment diagnosis,differential diagnosis,rehabilitation strategy and prevention of SS,in order to provide clinical reference.

Objective : To investigate the etiology, clinical manifestations, treatment and prevention of jaw necrosis caused by arsenic trioxide to provide a reference for clinical diagnosis and treatment. Methods: To analyze the clinical data and related literature of patients with jaw necrosis caused by acute promyelocytic leukemia treated with arsenic trioxide Results: We report a case of jaw necrosis caused by the use of arsenic trioxide (10 mg once a day for one month) during the treatment of acute promyelocytic leukemia. About 20 days after treatment, the patient developed right maxillary pain accompanied by gingival redness and swelling and mucosal ulcer, 14-17 teeth had buccal and palatal alveolar bone exposed, gingival mucosa was missing, gingival tissue was damaged to the bottom of vestibular groove, and palatal soft tissue was damaged to 5-8 mm of palatal suture. Due to the unstable condition of acute promyelocytic leukemia, the patient was given conservative treatment such as oral vitamin and Kangfuxin liquid gargle to keep his mouth clean. Drug induced jaw necrosis reported in the literature can be caused by bisphosphonates. Arsenic trioxide can also cause local jaw necrosis. Clinically, it is often manifested as long-term wound nonunion, pus, alveolar bone or jaw bone exposure, dead bone formation, accompanied by pain, loose teeth, facial swelling and other symptoms. Anti inflammation, debridement and surgical removal of dead bone are commonly used treatment methods. Conclusion In clinical practice, we should be alert to drug-induced jaw necrosis and strengthen prevention.

Immune checkpoint inhibitors (ICIs) present significant efficacy in the treatment of malignant tumors, and they have been approved as the first-line of treatment for various cancers. Pembrolizumab monotherapy or combined with chemotherapy has been recommended by domestic and foreign guidelines for the first-line treatment of recurrent/metastatic head and neck squamous cell carcinoma. Although ICIs represent a milestone in the treatment of head and neck squamous cell carcinoma, potential problems still need to be addressed, such as the selection of the efficacy predictors for ICIs, the evaluation of the tumor response to ICIs, and the treatment of immune hyperprogression and immune-related adverse events. Therefore, to form a relatively unified understanding of ICIs treatment for head and neck squamous cell carcinoma, we integrated the clinical experience of multi-disciplinary experts of head and neck cancers on the basis of current clinical hot issues and finally developed this consensus.
Humans ; Squamous Cell Carcinoma of Head and Neck/drug therapy* ; Immune Checkpoint Inhibitors ; Consensus ; Neoplasm Recurrence, Local/pathology* ; Head and Neck Neoplasms/drug therapy*

Objective : To analyze the accuracy of the infiltrating depth of tongue squamous cell carcinoma measured by magnetic resonance imaging (MRI) using pathological sections under a light microscope to provide a clinical reference. Methods : Seventy-three patients with tongue squamous cell carcinoma who visited the Department of Stomatology of the First Hospital of Shanxi Medical University and Xiangya Stomatological Hospital from January 2018 to September 2020 were selected. Preoperative MRI was performed to evaluate the infiltration depth of tongue squamous cell carcinoma, and intraoperative frozen pathological sections were used to confirm the infiltration depth of tongue squamous cell carcinoma measurement. Results : The infiltration depth of tongue squamous cell carcinoma measured by T1-weighted imaging was 1.11 mm (95% CI=0.51-1.70; t=3.72; P < 0.001), and the correlation coefficient r was 0.95. The T2-weighted average overestimation was 2.17 mm (95% CI=1.32-3.02; t=5.10; P < 0.001), and the correlation coefficient was 0.92. The Bland-Altman plot showed good consistency between T1- and T2-weighted images and pathologic measurements. Conclusion The infiltration depth of tongue squamous cell carcinoma measured by MRI is more accurate, with an average overestimation of 1-2 mm compared with pathological measurements, and T1-weighted images are better than T2-weighted images.

Adenoviridae/genetics* ; Consensus ; Head and Neck Neoplasms/therapy* ; Humans ; Tumor Suppressor Protein p53/genetics*

Objective : To provide an experimental basis for predicting the sample size needed for animal experiments by studying the survival of SD rats after buccal mucosal biopsy with arecoline administered at different concentrations with different methods. Methods : In all, 48 rats were divided into 8 groups, with 6 in each group, as follows: rats in groups A-D were treated with arecoline at different concentrations (0, 0.5, 2, 8 mg/mL); rats in groups E-H were treated with arecoline at different concentrations (0, 0.5, 2, 8 mg/mL), followed by stimulation of the buccal mucosa by mechanical rubbing. After 16 weeks, a 6-mm-diameter sample of the buccal mucosa was collected, and the wound was closed with interrupted sutures. The survival time of the rats was recorded, and the relationship between the survival time and the concentration of arecoline and mechanical stimulation was analyzed. Results: No rats died during the first 16 weeks after treatment or after biopsy. The success rate of the arecoline stimulation model was 66.7%. The average observation time of all SD rats after biopsy was 42.5 days. Up to 120 days after biopsy, the cumulative survival rate in the eight groups was 50%, 33%, 17%, 0%, 33%, 17%, 0% and 0%, respectively (in alphabetical order). The cumulative survival rate in the groups administered 0 mg/mL (groups A and E), 0.5 mg/mL (groups B and F), 2 mg/mL (groups C and G), and 8 mg/mL (groups D and H) was 42%, 25%, 8% and 0%, respectively. Cox survival analysis showed that moderate and high concentrations of arecoline (2, 8 mg/mL) significantly affected the survival duration (P < 0.05), while mechanical stimulation had no significant effect on the survival duration (P > 0.05). The chi-squared test showed that the survival rate of rats showing wound healing (33.3%) was significantly higher than that of rats showing incomplete wound healing (0.0%) (P=0.003). Conclusion The success rate of the rat buccal submucosal fibrosis model was higher than moderate and high concentrations of arecoline, but the survival duration was significantly reduced after biopsy. Mechanical stimulation did not lead to a significant decrease in the survival duration, and impaired wound healing may be a cause of death in this model.

Objective: To explore the etiology, clinical manifestation, diagnosis and treatment of white spongy spot nevus, so as to provide reference for clinical diagnosis and treatment. Methods : The clinical data and related literature of a case of white cavernous nevus in oral cavity were retrospectively analyzed. Results : White spongy nevus is a rare autosomal dominant hereditary disease with a family history. The mutations of keratin gene K4 and K13 in patients with white spongy nevus are considered to be the main causes. The disease usually starts in children and adolescents and tends to be stable in adulthood. It is characterized by extensive white water-wave folds on the mucosa, soft texture, and affects the bilateral buccal mucosa. Pathological examination usually shows excessive keratosis of epithelial cells, edema and vacuolation in spinous cells, while basal cells are generally normal. In clinic, it should be differentiated from oral leukoplakia, oral lichen planus and oral candidiasis. At present, there is no specific treatment method. Retinoic acid is often applied locally and gargle is used to keep oral hygiene and cleanliness. Patients can not be treated without conscious symptoms. The prognosis of the disease is good and there is no tendency of malignancy. Conclusion White spongy nevus is very rare and easily missed by clinicians. Diagnosis mainly depends on medical history, clinical manifestations and pathological examination. Future research directions should be devoted to finding more effective treatment.