Objective To evaluate the clinical efficacy of percutaneous transluminal angioplasty (PTA) combined with stent implantation in the treatment of transplant renal artery stenosis (TRAS) after renal transplantation. Methods Clinical data of 21 patients with TRAS after renal transplantation undergoing PTA combined with stent implantation were retrospectively analyzed. The incidence of TRAS in renal transplant recipients was summarized. The changes of relevant indexes in patients with TRAS were statistically compared before and after interventional treatment. Clinical prognosis of patients with TRAS was evaluated. Results The incidence of TRAS in renal transplant recipients was 4.1%(21/507). TRAS was diagnosed at postoperative 5 (4, 7) months, and 67% (14/21) of patients developed TRAS within postoperative 6 months. Compared with the values before interventional therapy, the serum creatinine level, systolic and diastolic blood pressure and peak flow velocity of transplant renal artery of patients with TRAS were significantly decreased, and the estimated glomerular filtration rate (eGFR) and interlobar arterial resistance index were significantly increased at 1 week and 1 month after interventional therapy (all P < 0.05). During postoperative follow-up after PTA combined with stent implantation, 1 patient suffered re-stenosis of the transplant renal artery, which was improved after simple balloon dilatation. One patient developed pseudoaneurysm formation at the puncture site of the right femoral artery. One patient presented with renal atrophy and loss of function due to atresia of the transplant renal artery. All the remaining 18 patients were well recovered after surgery. Conclusions PTA combined with stent implantation is the optimal treatment of TRAS after renal transplantation, which can significantly improve the function of transplant kidney and considerably prolong the survival time of transplant kidney.

Objective This study aimed to evaluate the clinical outcomes of immediate implantation of single maxil-lary central incisor and explore factors affecting post-implant bone volume.Methods Clinical data and imaging records from pre-surgery,the day of surgery,and 6 months post-surgery of 100 patients(100 implants)with non-salvageable maxillary central incisors who underwent immediate implantation were collected.Bone thickness at the cervical,middle,and apical regions of the implant's labial and palatal sides were measured immediately post-surgery and at 6 months,and bone volume changes were observed.A regression analysis model was used to assess predictive factors for labial and pal-atal bone plate thickness.Results At 6 months post-surgery,the labial bone thicknesses at the cervical,middle,and api-cal regions were 2.35,2.29,and 3.28 mm,respectively,and those of the palatal side were 0.00,2.40,and 6.05 mm,re-spectively.The cervical region had the highest alveolar crest collapse rates,with 32.87%on the labial side and 62.20%on the palatal side.The regression model indicated that factors influencing the thickness of bone at the cervical labial side of the implant included initial bone thickness,the implant center to adjacent tooth center angle,implant diameter,and the type of implant closure(P<0.05).The initial bone thickness on the palatal side was the sole predictor for bone thickness on the palatal side(P<0.05).Conclusion Immediate implantation of single maxillary central incisors yields effective clinical results.The thickness of new bone around the implant is influenced by multiple factors.A comprehensive consideration of these factors in the plan-ning of immediate implantation is necessary to achieve optimal therapeutic outcomes.