Objective:To explore the effect of digital technology and 3D printing technology combined with non-vascularized ilium bone in repairing post-traumatic bone defect in maxillary anterior area.Methods:A retrospective case series study was performed to analyze clinical data of 8 patients with severe bone defect in maxillary anterior area after trauma admitted to First Affiliated Hospital of Zhengzhou University from June 2013 to January 2018. There were 6 males and 2 females, with the age of 18-43 years [(31.9±9.0)years]. The maxillary bone was reconstructed before surgery by employing digital technology. The intercept range of ilium was determined according to the best form of defect to be recovered. Then the model and guide plate was printed out by employing 3D print technology. The titanium mesh was prebended on the model. The bone was extracted and Onlay bone grafting was performed according to the guide plate. The implant restoration was performed 6 to 9 months after operation, and porcelain crown restoration was performed 4 to 6 months later. The iliac bone survival and postoperative complications were detected 6 months after bone grafting. The near-middle-far and vertical bone elevation of the alveolar ridge as well as bone elevation of lip palatal were measured before implantation. The condition around the implants was observed 6 months after porcelain crown restoration. The visual analogue score (VAS) was used to evaluate the pain after iliac bone transplantation and implantation. The implant stability coefficient (ISQ) was applied to assess the stability of the implants on the day and 4 months after operation.Results:All the patients were followed up for 24-48 months [(33.3±9.7)months]. Eight patients with non-vascularized iliums were all survived. There was one patient with mild infection after bone grafting and one patient with gingival inflammatory hyperplasia after implantation, both of whom were healed after treatment. There was no obvious peri-implant inflammation or absorption of the grafted bone. The increase in height of the alveolar on the mesial and distal bone, vertical bone and labial-palatal bone was 30.28-39.67 mm, 9.58-11.32 mm and 2.06-7.41 mm, respectively. All the implants showed good osseointegration. The VAS after implantation was (3.4±0.7)points, significantly alleviated compared with the preoperational level [(7.3±2.0)points] ( P<0.05). The ISQ was 84.4±1.9 at postoperative 4 months, showing no significant difference from that on the day after operation (72.9±1.4) ( P>0.05). Conclusions:In repair of severe bone defect in maxillary anterior area after trauma, the digital and 3D printing technology combined with non-vascularized ilium can improve the survival rate of bone grafts. The implant restoration after operation can reduce pain, restore the patients' facial appearance and achieve satisfactory oral physiological function.

Objective To evaluate the efficacy of different interventions to the extra cranial lesions in acute ischemic stroke(AIS)due to anterior tandem lesions(TL)on reperfusion.Methods As a multi-center,cross-sectional study,AIS due to anterior TL receiving mechanical thrombectomy(MT)were retrospectively collected.Interventions to the extra-cranial stenosis were recorded.Post-procedural reperfusion was assessed using the modified thrombolysis in cerebral infarction(mTICI)score.Complete revascularization was defined as mTICI 3 and good revascularization was defined as mTICI 2b/3.The relationship between different extra-cranial intervention regi-mens and rate of re-vascularization was compared.Results Totally 117 patients were included with 92.3% reaching good recanalization and 63.2% reaching complete re-canalization.There was no significant difference in good re-canalization rates among various extra-cranial intervention regimens.The rate of complete re-canalization was significantly higher in patients receiving endovascular therapy(P＜0.05)and there was significant difference among various endovascular treatment regimens(P＜0.01):acute balloon angioplasty only group presented the highest rate of complete re-canalization(100.0% ),followed by acute stenting only group(80% ),acute stenting+balloon angioplasty group(73.7% )and conservative treatment group(54.3% ).Conclusions Endovascular inter-vention to extra-cranial stenosis contributes to complete re-canalization in AIS due to anterior TL receiving MT,and acute balloon angioplasty seems to be quite effective than acute stenting.