BACKGROUND:Apexification and mineral trioxide aggregate apexification are mainly used to treat pulpal necrosis in the immature permanent tooth, but neither methods can increase the root canal length and thickness. How to promote the root development of the affected teeth based on patients' potential? Pulp regeneration and revascularization has provided a new direction for clinical treatment, but successful cases are rarely reported. OBJECTIVE: To testify the clinical effectiveness of pulp regeneration and revascularization in the treatment of pulpal necrosis, root development stagnation in the permanent teeth caused by caries, odontodysplasia and injury, thus providing reference for clinical application. METHODS:We propose to conduct a prospective, single-center, randomized, controlled, clinical trial at Stomatological Hospital Affiliated to Xi'an Jiaotong University, Shaanxi Province, China. Eighty-two patients (82 affected teeth) with pulpal necrosis or periapical periodontitis in the immature permanent tooth from December 2013 to December 2016 were selected, and equally randomized into trial and control groups, followed by treated with pulp regeneration and revascularization, and apexification, respectively. The clinical examinations and X-ray radiology were used to evaluate the clinical effectiveness at 3, 6, 9, 12 and 18 months, and the pulp vitality and rot development were observed. The study protocol has been approved by the Ethics Committee of Stomatological Hospital Affiliated to Xi'an Jiaotong University of China (approval number: JDKY015-02). All protocols were performed in accordance with the Ethical Principles for Medical Research Involving Human Subjects in theDeclaration of Helsinki. Written informed consent was provided by each patient and their family members after they indicated that they fully understood the treatment plan. RESULTS AND CONCLUSION: Up to March 25, 2017, all patients have been followed up for 6.5-18 months. The treatment success rate in the trial and control groups was 97.6% and 82.9%, respectively, and the intergroup difference was significant (P < 0.05). The positive rate of pulp vitality in the trial and control groups was 24.4% and 0, respectively, which showed significant difference (P < 0.05). The rate of root continuous development showed significant difference between trial and control groups (63.4%vs. 29.3%,P < 0.05). To conclude, compared with apexification, pulp regeneration and revascularization exhibits high success rate in the treatment of pulpal necrosis in the immature permanent tooth, and can contribute to root development.

Objectives:To analyze the clinical characteristics of patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) and identify the risk factors for death.Methods:The clinical data of 60 patients undergoing ECPR admitted to our hospital and Hangzhou First People's Hospital from September 2014 to September 2019 were retrospectively analyzed. The patients were divided into the survival group and the death group. The clinical data of the two groups were compared to explore the risk factors related to death. COX regression analysis was used to identify the risk factors for death.Results:Sixty patients undergoing ECPR were included in our study, of them, 16 (26.7%) cases were out-of-hospital cardiac arrest (OHCA) and 44 (73.3%) cases were in-hospital cardiac arrest (IHCA). The mortality of OHCA patients was higher than that of IHCA patients (87.5% vs. 56.89%, P < 0.05), and the duration from CPR to ECMO installation in the death group was longer than that in the survival group [(105.4±105.1) min vs. (53.0±28.5) min, P < 0.05]. Compared with the survival group, patients in the death group had higher troponin and glutamic oxalacetic transaminase and lower PH and lactate ( P < 0.05). The median survival time of the 60 patients was 42 days. Out-of-hospital cardiac arrest, high SOFA score before ECMO, high-dose norepinephrine, pulmonary infection during ECMO support and long ECMO support time were independent predictors of patients’ death. Conclusions:Risk factors associated with patients’ death undergoing ECPR are out-of-hospital cardiac arrest, high SOFA score before ECMO, high-dose norepinephrine, long duration from CPR to ECMO installation, pulmonary infection during ECMO support and long ECMO support time.