OBJECTIVE: Dynamic navigation approaches are widely employed in the context of implant placement surgery. Implant surgery can be divided into immediate and delayed surgery according to the time of implantation. This retrospective study was developed to compare the accuracy of dynamic navigation system for immediate and delayed implantations. METHODS: In the study, medical records from all patients that had undergone implant surgery between August 2019 and June 2021 in the First Clinical Division of the Peking University School and Hospital of Stomatology were retrospectively reviewed. There were 97 patients [53 males and 44 females, average age (47.14±11.99) years] and 97 implants (delayed group: 51; immediate group: 46) that met with study inclusion criteria and were included. Implant placement accuracy was measured by the superposition of the planned implant position in the preoperative cone beam computed tomography (CBCT) image and the actual implant position in the postoperative CBCT image. The 3-dimensional (3D) entry deviation (3D deviation in the coronal aspect of the alveolar ridge), 3D apex deviation (3D deviation in the apical area of the implant) and angular deviation were analyzed as the main observation index when comparing these two groups. The 2-dimensional (2D) horizontal deviation of the entry point and apex point, and the deviation of entry point depth and apex point depth were the secondary observation index. RESULTS: The overall implant restoration survival rate was 100%, and no mechanical or biological complications were reported. The implantation success rate was 100%. The 3D entry deviation, 3D apex deviation and angular deviation of all analyzed implants were (1.146±0.458) mm, (1.276±0.526) mm, 3.022°±1.566°, respectively; while in the delayed group these respective values were (1.157±0.478) mm, (1.285±0.481) mm and 2.936°±1.470° as compared with (1.134±0.440) mm, (1.265±0.780) mm, 3.117°±1.677° in the immediate group. No significant differences (P=0.809, P=0.850, P=0.575) in accuracy were observed when comparing these two groups. CONCLUSION Dynamic computer-assisted implant surgery system promotes accurate implantation, and both the immediate and delayed implantations exhibit similar levels of accuracy under dynamic navigation system that meets the clinical demands. Dynamic navigation system is feasible for immediate implantation.
Humans ; Male ; Female ; Retrospective Studies ; Middle Aged ; Cone-Beam Computed Tomography ; Dental Implantation, Endosseous/methods* ; Surgery, Computer-Assisted/methods* ; Dental Implants ; Adult ; Surgical Navigation Systems ; Immediate Dental Implant Loading/methods* ; Imaging, Three-Dimensional

Objective To summarize the experience in operation manner and surgical technique of refractory cholelithiasis.Methods A total of five hundred and twenty one patients with refractory cholelithiasis admitted to Hunan Provincial People's Hospital from Jan.1990 to Dec.2007 were involved in this study for retrospective analysis.Results All patients in this group accepted surgery.Apart from three cases of perioperative death with liver and kidney failure,the remaining five hundred and eighteen cases had no serious complications,were cured and discharged.The imaging examination showed residual stone in seventy cases,accounting for fifteen percent.Four hundred and twenty one patients were followed up.The mean time of follow-up was seven years and six months (range 5 months - 17 years).Good result rate was 90.1%(381/423).Conclusions Most intractable cholelithiasis can be cured radically.Individual surgery programme,fine and standard surgical procedure are the key to treatment effect.

Objective To assess the causes and methods of surgical treatment of hepatolithiasis reoperation Methods The clinical data of 81 cases of hepatolith reoperation were analyzed retrospectively. Results The main causes of hepatolith reoperation include biliary stricture,biliary tract variation,cholangiocarcinoma, etc. The chief reoperation patterns were hepatic lobectomy, Roux-en-Y hepaticojejunostomy, and lobectomy combined with Roux-en-Y hepaticojejunostomy.A follow-up of 2 months to 12 months showed excellent (outcome) of 93.8% of cases. According to postoperative cholangiograph,the retained stone rate was 6.2%. Conclusions When treating cholelithiasis ,we should follow the following principles: remove stones, relieve biliary stricture, correct biliary variation, resect abnormal liver, and establish adeguate biliary drainage.