Clinical Implant Dentistry and Related Research最新文献

Objective

This study aimed to compare the implant placement accuracy and systematic precision between Robotic-Assisted Implant Surgery (RAIS) and Fully Guided Static Computer-Assisted Implant surgery (sCAIS), as well as to explore factors influencing implant placement accuracy.

Materials and Methods

Patients who underwent digital guided implant surgery between October 2022 and July 2024 were included in this study. The patients were divided into the RAIS and sCAIS groups. Post-operative CBCT scans were performed to measure three-dimensional (3D) deviations and overlap rate (OR) of each implant. The differences in 3D deviations and OR between the two CAIS methods were analyzed, along with factors that could impact implant accuracy, such as anterior versus posterior sites, maxilla versus mandible, bone defects, implant morphology, and free-end sites.

Results

254 patients were enrolled, with 125 patients receiving 227 implants in the RAIS group and 129 patients receiving 227 implants in the sCAIS group. The RAIS group demonstrated significantly better performance than the sCAIS group in coronal global deviation (0.69 [0.52] mm vs. 0.97 [0.64] mm), apical global deviation (0.75 [0.57] mm vs. 1.40 [0.82] mm), angular deviation (1.51 [1.43]° vs. 3.44 [2.78]°), and OR (80 [17]% vs. 64 [20]%) (p < 0.001). There were no significant differences between the two groups in coronal horizontal mesiodistal deviation at the anterior sites, nor in coronal horizontal mesiodistal and buccolingual deviations at the posterior sites.

Conclusion

In most edentulous cases, implant placement accuracy assisted by the RAIS system was significantly higher than that of the sCAIS system. The control of Coronal horizontal (mesiodistal) deviation by sCAIS is comparable to that of RAIS. Additionally, the RAIS system demonstrated better systematic precision.

Objectives

To evaluate the effectiveness of a Mg-based membrane as a barrier for guided bone regeneration in rabbits calvaria.

Materials and Methods

Nine rabbits had four critical size defects created in each calvarium, randomly filled with a blood clot or bovine xenograft. One side was covered with the Mg-based membrane, and the control was left without membrane. After 8 weeks, histomorphometric analysis was performed to compare new bone formation with the pristine bone.

Results

Mg-supported membrane for guided bone regeneration (GBR) is safe and promotes bone formation in critical size defects (CSD) in a rabbit calvaria. Gas accumulation was observed in a third of the specimens due to membrane degradation. Histomorphometric analysis revealed greater bone formation in the defects grafted with the Mg membrane (4.85 ± 1.73 mm²) compared to the blood clot (2.14 ± 2.22 mm²). Treating lesions with filler or the magnesium membrane resulted in significantly higher bone formation in all three examined regions (25%–62%). New bone formation was observed beyond the original bone envelope.

Conclusion

Mg-based membrane supports guided bone regeneration (GBR), and when used in combination with a bone graft, enhances the performance despite the gas accumulation associated with membrane degradation.

Clinical Relevance

Limited data exist on the use of Mg-based membranes in GBR and its effect on bone formation.

Purpose

This study aimed to investigate the changes in healing abutments (HAs) after use based on an in vitro comparison with unused HAs and to evaluate the effectiveness and clinical implications of reusing HAs.

Materials and Methods

Fifty used HAs were collected from affiliated clinics of the Department of Dentistry at Hanyang University Hospital and analyzed for surface damage, protein contamination, and microgap formation using three-dimensional laser microscopy and microcomputed tomography. The interfacial microgap between the implant and the abutment was measured at different tightening torques (5 N·cm, 10 N·cm, and 15 N·cm). Additionally, bacterial leakage and growth at various tightening torques were assessed by incubating reused HAs over different time periods.

Results

Reused HAs exhibited significant surface roughness, protein contamination, and larger microgap compared to unused HAs. The average microgap for reused HAs was 43 μm, whereas unused HAs showed no detectable gap. Bacterial leakage was significantly higher with reused HAs, particularly in those subjected to more than two tightening cycles. Tightening torques of 15 N·cm effectively eliminated the microgap and minimized bacterial leakage, whereas lower torques (5 N·cm and 10 N·cm) resulted in considerable bacterial growth.

Conclusion

Reusing HAs increases the risk of surface damage, protein contamination, microgap formation, and bacterial leakage, potentially compromising implant treatment outcomes. Higher tightening torque, (15 N·cm) significantly reduces microgap and bacterial leakage at the implant - HA imterface. Clinicians are advised to limit the reuse of HAs. However, if reuse is necessary, an appropriate tightening torque should be applied following a careful assessment of the clinical conditions of each HA.

Objective

The primary aim was to investigate differences in patient-reported healing outcomes between static computer-assisted sinus floor augmentation (SCA-SFA) and the conventional freehand approach (SFA).

Material and Methods

Patient-reported healing outcomes were recorded in visual analog scale (VAS) on days 1–7 and 14, and intra and postoperative complications were assessed on weeks 2 and 4 after surgery. Operation time and operators' assessment of efficacy for SCA-SFA utility were recorded. Independent t-tests and Chi-square exact tests were performed for statistical evaluation between groups.

Results

Forty patients underwent lateral sinus augmentation (20 freehand-SFA + 20 SCA-SFA). No statistically significant difference was found between the two groups with regard to PROMs and intra, postoperative complications, apart from a higher level of swelling for SCA-SFA patients on day 2 after surgery (p = 0.04). The use of SCA-SFA significantly reduced the time needed to conduct the window osteotomy (SFA 18.56 ± 12.17 min vs. SCA-SFA 11.43 ± 4.75 min; p = 0.022) and the total surgery duration (SFA 69.89 ± 20.08 min vs. SCA-SFA 56.24 ± 16.01 min; p = 0.023).

Conclusions

Within the limitations of the study, SCA-SFA should be preferred when the reduction of surgical time is a priority while the costs of the intervention do not play a major role, and the design of the surgical guide should strive for minimal invasiveness.

Clinical Trial Registry: TCTR20230427005