Clinical implant dentistry and related research最新文献

Purpose: This randomized controlled clinical trial compared five implant osteotomy techniques-high-speed drilling (800 rpm), moderate-speed drilling (300 rpm), ultra-low-speed drilling (50 rpm), osseodensification, and bone condensation-with respect to insertion torque (IT), early implant stability quotient (ISQ) progression, and immediate postoperative VAS-anxiety during early osseointegration.

Materials and methods: One hundred healthy adults each received a single identical macrodesign implant and were randomly allocated to five osteotomy protocols (n = 20/group). Insertion torque was recorded at placement. ISQ was measured at placement (T0), 1 week (T1), 1 month (T2), 2 months (T3), and 3 months (T4). Immediate postoperative patient-reported anxiety was assessed using a 10-cm visual analog scale (VAS). Sites exhibiting IT < 25 Ncm were prespecified for submerged healing and excluded from longitudinal stability analyses. The primary endpoint was the change in ISQ from T0 to T4, with multiplicity controlled using Bonferroni-adjusted pairwise comparisons.

Results: A total of 100 implants were included in the final analyzed cohort. Four additional implants exhibited IT < 25 Ncm at placement and were therefore excluded from longitudinal ISQ analyses according to the predefined protocol. Across the analyzed implants, all groups achieved mean IT values exceeding 30 Ncm and baseline ISQ values > 80. Moderate-speed drilling (300 rpm) demonstrated the most consistent ISQ increase over time and achieved the highest stability at T4 (adjusted p < 0.05). High-speed drilling (800 rpm) produced the highest initial IT, particularly in high-density bone. Osseodensification showed transient mid-healing ISQ gains, whereas bone condensation exhibited a progressive decline in ISQ values. Immediate postoperative VAS-anxiety decreased significantly in all groups (p < 0.001); osseodensification was associated with higher residual anxiety, while bone condensation demonstrated the greatest reduction (adjusted p < 0.05).

Conclusions: Osteotomy technique influenced both mechanical stability trajectories and immediate postoperative patient-reported VAS-anxiety. Moderate-speed drilling at 300 rpm provided the most balanced stability profile within the 3-month follow-up. Osteotomy selection should be individualized according to bone density, mechanical requirements, and patient-related factors.

Trial registration: ClinicalTrials.gov identifier: NCT07234214.

Objective: To evaluate the relationship between cone-beam computed tomography (CBCT)-derived bone microstructure parameters and marginal bone loss (MBL) around platform-switched subcrestal implants over 1-8 years.

Methods: A retrospective analysis assessed 142 platform-switched implants in 100 patients. CBCT-based bone microstructure parameters-bone volume (BV), tissue volume (TV), bone volume fraction (BV/TV), bone surface (BS), bone surface fraction (BS/BV), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp)-were measured in peri-implant and cervical regions. Radiographic MBL was evaluated at baseline (T0: prosthetic insertion) and follow-ups (T1: 1-3 years post-loading, T2: 3-8 years post-loading). Associations between bone microstructure parameters and MBL were analyzed using Generalized estimating equations (GEE).

Results: GEE analysis of 142 implants from 100 patients, adjusting for covariates, linked baseline bone microstructure to MBL at T0, T1 and T2. No significant associations were found at T0 or T1 (p > 0.05). At T2, cervical bone microstructure parameters were not significant. However, peri-implant parameters were predictive: BV/TV was protective (B = -1.028, p = 0.0125), while BS/BV (B = 0.008, p = 0.0384) and Tb.Sp (B = 1.214, p = 0.0270) were significant risk factors for long-term MBL.

Conclusion: Peri-implant BV/TV, BS/BV and Tb.Sp might be critical predictors of long-term MBL progression in platform-switched subcrestal implants, while cortical bone thickness has limited impact. CBCT-based bone microstructure analysis could aid MBL risk prediction and clinical management.

Trial registration: This study has been registered in the Chinese Clinical Trial Registry, with the registration number ChiCTR2500098567.