Objective To study the effectiveness of niacinamide in treating maintenance hemodialysis patients with hyperphosphatemia.Methods It was a prospective and randomized controlled trial.Patients with hyperphosphatemia (serum phosphate ＞ 1.45 mmol/L) were randomly assigned into two groups:control group (continue their original phosphate binder and rocaltrol treatment) and niacinamide therapy group (additionally received niacinamide,titrated from 600 mg/d to 1200 mg/d).The treatment lasted for 8 weeks.Serum phosphate and calcium were tested every 2 weeks and normalized protein catabolic rate and other relevant indexes were tested monthly.Results 100 patients were recruited and 93 of them completed the trial,including 44 from the therapy group and 49 from the control group.By the repeated measures analysis of variance,changes of serum phosphate in two groups displayed a statistical significant difference,but the levels of serum calcium in both remained steady.At the end of trial,compared to control group,therapy group appeared decreased serum phosphate levels [(1.59±0.36) mmol/L vs (1.94±0.25) mmol/L,P ＜ 0.001] and increased serum HDL levels [(1.32±0.54) mmol/L vs (1.09±0.41) mmol/L,P=0.02].Meanwhile,two groups showed no significant difference in intact parathyoid hormone and alkaline phosphatase.Adverse reactions including thrombocytopenia and gastrointestinal dysfunction were observed in niacinamide therapy group.Conclusions Niacinamide is effective on controlling hyperphosphatemia along with phosphate binder in maintenance hemodialysis patients.It also increases the serum HDL levels.Nonetheless,it is important to monitor the number of platelet.

The standardized workflow of computer-aided static guided implant surgery includes preoperative examination, data acquisition, guide design, guide fabrication and surgery. Errors may occur at each step, leading to irreversible cumulative effects and thus impacting the accuracy of implant placement. However, clinicians tend to focus on factors causing errors in surgical operations, ignoring the possibility of irreversible errors in nonstandard guided surgery. Based on the clinical practice of domestic experts and research progress at home and abroad, this paper summarizes the sources of errors in guided implant surgery from the perspectives of preoperative inspection, data collection, guide designing and manufacturing and describes strategies to resolve errors so as to gain expert consensus. Consensus recommendation: 1. Preoperative considerations: the appropriate implant guide type should be selected according to the patient's oral condition before surgery, and a retaining screw-assisted support guide should be selected if necessary. 2. Data acquisition should be standardized as much as possible, including beam CT and extraoral scanning. CBCT performed with the patient’s head fixed and with a small field of view is recommended. For patients with metal prostheses inside the mouth, a registration marker guide should be used, and the ambient temperature and light of the external oral scanner should be reasonably controlled. 3. Optimization of computer-aided design: it is recommended to select a handle-guided planting system and a closed metal sleeve and to register images by overlapping markers. Properly designing the retaining screws, extending the support structure of the guide plate and increasing the length of the guide section are methods to feasibly reduce the incidence of surgical errors. 4. Improving computer-aided production: it is also crucial to set the best printing parameters according to different printing technologies and to choose the most appropriate postprocessing procedures.