Intentional tooth replantation (ITR) is an advanced treatment modality and the procedure of last resort for preserving teeth with inaccessible endodontic or resorptive lesions. ITR is defined as the deliberate extraction of a tooth; evaluation of the root surface, endodontic manipulation, and repair; and placement of the tooth back into its original socket. Case reports, case series, cohort studies, and randomized controlled trials have demonstrated the efficacy of ITR in the retention of natural teeth that are untreatable or difficult to manage with root canal treatment or endodontic microsurgery. However, variations in clinical protocols for ITR exist due to the empirical nature of the original protocols and rapid advancements in the field of oral biology and dental materials. This heterogeneity in protocols may cause confusion among dental practitioners; therefore, guidelines and considerations for ITR should be explicated. This expert consensus discusses the biological foundation of ITR, the available clinical protocols and current status of ITR in treating teeth with refractory apical periodontitis or anatomical aberration, and the main complications of this treatment, aiming to refine the clinical management of ITR in accordance with the progress of basic research and clinical studies; the findings suggest that ITR may become a more consistent evidence-based option in dental treatment.
Humans ; Tooth Replantation/methods* ; Consensus ; Periapical Periodontitis/surgery*

Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans ; Root Canal Therapy/adverse effects* ; Consensus ; Root Canal Preparation/adverse effects*

Objective To explore the main factors affecting the MV imager projection offset in the machine performance check(MPC)for Varian Vital Beam linear accelerator.Methods The MV imager projection offsets in the MPC after repairing the MV imaging arm encoder of shoulder motor,locking the treatment couch,and isocenter calibration were analyzed.Results MPC results revealed that the MV imager projection offset after repairing the MV imaging arm encoder of shoulder motor was(0.310±0.001)mm,significantly less than(0.450±0.010)mm in the blank group.The difference in MV imager projection offset between the isocenter calibration group and the blank group was trivial.The MV imager projection offset after locking the treatment couch was(0.240±0.030)mm,significantly less than(0.450±0.010)mm in the blank group.When MPC was carried out after repairing the imaging arm encoder and performing isocenter calibration,there was no significant statistical difference in MV imager center offset between the locked and unlocked treatment couch.Conclusion The damage of MV imaging arm encoder of shoulder motor is the main factor causing abnormal MV imager projection offsets.Locking the treatment couch before the MV imaging center check can reduce the results,but it cannot eliminate the MV imager projection offset.

Ewing sarcoma is a member of the Ewing sarcoma family tumor(ESFT), which is commonly from bones and soft tissues, while it is rare for penis. In this thesis, a case of 21-year-old Ewing sarcomas on the left side of the penis was reported. After the penis mass excision, the pathological diagnosis was Ewing sarcoma and positive margin, then he underwent penis total hysterectomy. After the surgery, he received chemotherapy for 14 cycles without radiation. With 8 months’ reexamination and follow-up, there was no local recurrence or metastasis.

Objective To evaluate the reliability of CT perfusion parameter values of the normal hepatic segments and neoplasms, obtained with deconvolution (DC) and maximum slope (MS) algorithms. Methods Perfusion parameter values of 111 ROIs in 62 normal hepatic segments and 49 neoplasms derived from 62 CT perfusion studies performed with 320 multi-slice CT, were retrospectively analyzed by two experienced radiologists. BF,BV and PI according to DC and MS algorithms were compared with t paired test, Pearson correlation and Bland-Altman agreement analysis. Interobserver agreement for all perfusion parameters was calculated using intraclass correlation coefficients (ICC). Results Interobserver agreement measured with ICC was very good for all perfusion parameters (≥0.95). BFdc and BVdc exceeded the BFms and BVms in normal hepatic segments and neoplasms (P<0.05); PIdc significantly exceeded the PIms in normal hepatic segments(P<0.05) ,while no difference were found in hepatic neoplasms(P>0.05). Both pairs of perfusion measurements significantly correlated with each other(r>0.9, P<0.01),but the agreement of BF, BV and PI according to DC and MS algorithms was not good. Conclusions CT perfusion values such as BF,BV and PI obtained by DC and MS algorithms correlated significantly with each other, but with poor agreement.

Objective:To discuss the diagnosis, treatment and outcome of patients with gliomatosis cerebri (GC). Methods:Retrospectively reviewed the clinical manifestations and radiological appearances of 6 patients with GC, which were diagnosed in our hospital between 1993 and 2003. We employed surgical treatment in three patients, stereotactic biopsy in two, and the other one received both biopsy and surgery. Results: The lesions of GC infiltrated more than two lobes in brain. CT studies showed diffuse hypodensity changes and enhancement was absent in four patients. MRI examinations revealed isointense or hypointense regions on T1WI, and uniformly high signal on T2WI. MRI also disclosed structural enlargement. All patients received radiotherapy after surgery and three patients underwent chemotherapy additionally. Five patients died during follow up with average course of 16.4 months. Conclusion:MRI examination is valuable in the diagnosis and the prognosis of GC is poor.

Objective To review the features of diagnosis and treatment of craniocerebral firearm wounds in peacetime. Methods A total of 86 cases with various kinds of firearm wounds were retrospectively analyzed for discussing the characteristics of diagnoses and treatment of firearm wounds so as to provide the best treatment methods for firearm wounds of the brain. Results Of all, 80 cases (93%) won full recovery and four (5%) partial recovery but two (2%) were died of massive vascular damage and severe cerebral injuries within 24 hours after operation. Conclusions Craniocerebral firearm wounds are among the most devastating causes for morbidity and mortality in the civilian population. It is important to remove all foreign bodies, especially broken bones and necrotic tissues, and turn the open injury to the close injury. Stereotactic technique, localization of foreign bodies, culture of foreign body bacteria, drug allergy test and correct use of antibiotic and antiepileptic drugs are also critical for eliminating mortality and complications of craniocerebral firearm wounds.

Essential hypertension, which is common in population, has an unclear etioligy and the medical therapy is predominantly used. In the last few years, some studies found that the blood pressure could be elevated with the pulsatile compression at the root entry zone（REZ） of the Ⅸ、Ⅹcranial nerve, which may considered to be one of the causes of essential hypertension. Neurovascular decompression moderates the pulsatile compression, and is to be a new method for the treatment of essential hypertension, especially for refractory hypertension. This article summarized the mechanism of neurovascular decompression for essential hypertension and the operative courses.

Objectives:To discuss the effects of stereotactic techniques in treating brain deep lesions. 　Methods: Eighty-two patients with deep brain lesions were treated by fisher stereotactic apparatus and ASA-601S. Among these, stereotactic biopsy was performed in 22, clearance of haematoma in 5 (2 located in brain stem), aspiration of brain abscess in 2 and placement of Ommaya tube into cystic craniopharyngioma in 53.　Results: All of the 22 biopsies were pathologically diagnosed, which included 10 cases of glioma, 4 cases of germ cell tumor, 3 cases of brain parasite, 4 cases of metastatic lung tumor and one case of hyperplasia of colloid cells at rear end of third ventricle, which turned to be glioma in follow-up period. Tumor resection was performed in 4 patients with glioma and radiation therapy for other tumors. After the treatment, 6 patients were fully recovered ( 4 with germ cell tumor and 2 with metastatec tumor). All brain parasite, brain abscess and brain haematoma were cured. Three patients with craniopharyngioma were cured after the placement of Ommaya tube (with radiation therapy inside the cyst), and others were improved. 　Conclusions:Stereotaxy has the advantages of precise location, less damage, easy manipulation and on the safe side. It is worth advocating.