Clinical Implant Dentistry and Related Research最新文献

Introduction

In many clinical cases, anatomical conditions such as an atrophied alveolar ridge do not allow insertion of normal diameter implants. At this point, narrow dental implants may provide an effective option to avoid complex surgical treatments. The aim of this trial was to evaluate long-term survival, prosthetic and biological complications, and OHRQoL for two-piece narrow dental implants supporting overdentures with Locator-attachments.

Methods

Twenty-five patients with edentulous mandibles received four narrow dental implants and retained dentures with Locator attachments. Following successful implantation, immediate loading of anterior implants with Locator attachments was performed, while posterior implants underwent a conventional healing procedure. Follow-up examinations included documentation of implant and denture-related complications, modified gingiva index, modified plaque index, OHIP-G, and radiographic measurements of bone loss.

Results

Up to 9 years after restoration, 18 patients with 72 implants were available for the follow-up. During the observation period, one implant was lost in the immediate loading group. Implant survival was 98% and 100%. The outcomes of mPI and mGI for the 18 patients hardly differed between the groups. During the observation period, 136 prosthetic complications occurred. Scores for the different OHIP-G domains at the last follow-ups were stable over the years.

Conclusions

Throughout an extended period of observation, we found stable implant survival rates, good maintenance of oral hygiene, and manageable prosthetic complications. The OHRQoL was satisfying over the years, suggesting that this treatment option could be favorable for older individuals.

Trial Registration

https://drks.de/search/en/trial/DRKS00005497

Objective

This study aims to develop an innovative dry preservation surface modification for strontium-modified pure titanium implants to prevent surface degradation by hydrocarbon pollutants in the air and to enhance osseointegration.

Methods

An optimal parameter dry preservation surface modification was established by immersing samples in a 0.1 M KCl + 0.1 M SrCl₂ mixed solution for 12 h, followed by air-drying and storing in sealed glass vials, as the strontium-doped dry preservation (SrP) group. Surface characteristics were analyzed using appropriate instrumentation. Cell adhesion, proliferation, and osteogenic differentiation were assessed in in vitro studies. Forty-eight male Sprague–Dawley rats were included in in vivo studies, with a total of 96 implants placed bilaterally in the tibiae. Micro-CT, removal torque tests, and histological analyses after 4 or 8 weeks were conducted in order to evaluate the osseointegration in each group.

Results

Four distinct groups were involved in this study: the SrP group, the freshly prepared strontium-doped (SrF) group, the strontium-doped group with no dry preservation (SrN), and the modified sand-blasted large grit acid-etched (modSLA) group. After 6 months of storage, the SrP surface maintained favorable hydrophilicity, micro-nano morphology, and consistent strontium ion release similar to SrF. Moreover, it maintained similar levels of cell proliferation and osteogenic differentiation as SrF while exhibiting significantly better performance than SrN in in vitro studies (p < 0.05). Additionally, after 12 months of storage, it demonstrated excellent osseointegration comparable to the SrF group while significantly outperforming SrN in in vivo studies 4 weeks post-surgery (p < 0.05).

Conclusion

The dry preservation surface modification successfully maintained the nanotopography and hydrophilicity of strontium-doped pure titanium implants during 6–12 months of storage, and effectively mitigated the premature release of strontium ions associated with wet preservation methods, thereby significantly preserving the osseointegration performance of strontium-doped titanium implants.

Background

The horizontally insufficient posterior mandibular ridge frequently restrains dental implant insertion.

Patients and Methods

A modified ridge split procedure was innovated to separate, convey laterally, and fix the buccal cortical plate in 20 patients with posterior horizontal mandibular alveolar deficiency. Meanwhile, the intercancellous space was obliterated with autogenous bone particulates for the test group patients and Anorganic bone bovine mineral (ABBM) for those of the control group. Following a comparison of the horizontal bone gain and the histomorphometric bone area percent among both groups after 6 months of graft consolidation, 40 implants were inserted during the second surgical stage.

Results

All of the grafts were consolidated. A statistically insignificant difference was found between the control group's mean 6-month postoperative horizontal bone width of (8.10 ± 0.83) and that of the study one of (7.90 ± 0.77). The control group's mean bone gain was recorded (4.76 ± 0.81) versus (4.63 ± 0.78) for the study group, with a statistically insignificant difference. Both groups showed histological evidence of a moderate number of osteoblasts, mature trabecular bone, and lamellae encircling large fatty marrow spaces. A statistically significant difference (p = 0.021) was found between the control group's mean bone area percentage of new bone formation (38.83% ± 1.17%) and that of the study group (34.40% ± 3.71%).

Conclusion

The modified ridge split with either autogenous or (ABBM) graft was deemed reliable for reconstructing the horizontally deficient posterior alveolar ridge with appropriate volumetric stability and bone quality.

Trial Registration: The study was registered on www.clinicaltrials.gov (Registration #: NCT05286541)

Objectives

To investigate the trueness of intraoral photogrammetry (IPG) technology for complete-arch implant digital impression and evaluate the effect of implant number.

Material and Methods

All data were fully anonymized in compliance with ethical standards, and a total of 30 complete-arch patient models with 4 (n = 13), 5 (n = 9), or 6 (n = 8) implants were selected from the archive. Digital impressions were taken with IPG and a desktop scanner. Test and reference standard tessellation language (STL) files were superimposed using a best-fit algorithm. For each implant position, mean linear (ΔX, ΔY, ΔZ axes) and angular deviations (ΔANGLE) and three-dimensional (3D) Euclidean distances (ΔEUC) were measured as primary outcomes with a dedicated software program (Hyper Cad S, Cam HyperMill, Open Mind Technologies) and reported as descriptive statistics. Secondary aim was to determine using linear mixed models whether implant number affected trueness. All statistical analyses were conducted using Stata 18 (Stata Corp, College Station) and significance was set at 0.05.

Results

A total of 30 definitive casts with 4 (n = 13), 5 (n = 8), and 6 (n = 9) multi-unit abutment (MUA) analogs were analyzed (n = 146 implant positions). The mean deviations along the X-axis were −3.97 ± 32.8 μm, while along the Y-axis, they were −1.97 ± 25.03 μm. For the Z-axis, a greater deviation of −33 ± 34.77 μm was observed. The 3D Euclidean distance deviation measured 57.22 ± 27.41 μm, and the angular deviation was 0.26° ± 0.19°. Statistically significant deviations were experienced for ΔZ, ΔEUC, and ΔANGLE (p < 0.01). Additionally, the number of implants had a statistically significant effect only on the Z-axis deviation (p = 0.03).

Conclusions

Within study limitations, IPG technology was feasible for complete-arch digital implant impression with mean linear, angular, and 3D deviations far below the acceptable range for a passive fit. Reported IPG trueness might avoid a rigid prototype try-in. The implant number had no influence on trueness except for Z-axis deviations. Integrating photogrammetry with intraoral optical scanning (IOS) improved practicality, optimizing the digital workflow. Further clinical trials are needed to confirm these findings.

Aim

The objective of this study is to explore how different external sinus lifting approaches affect perioperative complications and patient comfort.

Materials and Methods

This prospective, randomized, controlled clinical study was conducted with patients who were admitted for rehabilitation of the posterior maxilla and met inclusion the criteria. Sinuses to be lifted were randomized into three groups: piezosurgery with a surgical guide, a specially designed bur for lateral sinus lift, and conventional burs. Intraoperative complications, ease of access, and operation time were recorded. Pain measured with visual analog scale (VAS) and analgesic consumption were evaluated over 1 week postoperatively. Edema was evaluated preoperatively and on the 2nd and 7th postoperative days. Patient expectations, experiences, and quality of life with the OHIP-14 questionnaire were assessed preoperatively and on the 7th postoperative day.

Result

30 sinus lifting procedures were conducted on 27 patients, comprising 16 men and 11 women. There were no statistically significant differences among the groups in terms of operation and osteotomy time, pain level, analgesic consumption, edema, patient experience, and quality of life (p > 0.05). However, significant differences were found regarding membrane elevation time (p < 0.05) and ease of access to the surgical site (p < 0.001) among the groups.

Conclusion

Piezo surgical approach assisted by a surgical guide appears advantageous in terms of operation time, surgical site accessibility, and quality of life. However, in cases where increased edema is expected, the use of specially designed burs for lateral sinus lift may be preferable.

Trial Registration: ID: NCT06601816. This randomized clinical trial was not registered before participant recruitment and randomization (https://register.clinicaltrials.gov/prs/beta/studies/S000EWSQ00000038/recordSummary)

Introduction

This study aimed to evaluate the efficacy of Biologically oriented Alveolar Ridge Preservation (BARP) in minimizing post-extraction ridge modifications compared with unassisted socket healing.

Methods

A prospective controlled observational study was conducted involving 30 patients requiring single-rooted upper premolar extractions. Patients were divided into two groups: the test (15 patients), which underwent a ridge preservation procedure combining absorbable collagen sponge in the middle and apical third of the socket and collagenated xenogeneic bone substitute in the most coronal part (BARP), and the control (15 patients), which healed spontaneously. Soft tissue contour changes after 6 months were analyzed using digital impressions. Moreover, histomorphometric analysis of the regenerated tissue was performed in the test group.

Results

BARP significantly reduced post-extractive mucosal ridge modifications compared to the control group. Mean vertical shrinkage at the mid-buccal part of the edentulous site was 1.61 ± 0.61 mm (BARP) vs. 2.51 ± 0.64 mm (control; t-test, df = 28, p < 0.001), and mean horizontal reduction was 3.37 ± 0.63 mm (BARP) vs. 4.34 ± 0.48 mm (control; t-test, df = 28, p < 0.001). Histomorphometric analysis of the regenerated tissue showed 39.7% ± 9.1% newly formed bone with minimal residual graft material (5.0% ± 5.4%).

Conclusion

BARP technique effectively minimizes post-extractive soft tissue contour modifications and supports natural bone regeneration, resulting in adequate bone dimensions for implant rehabilitation.

Objective

This study aimed to compare the accuracy of an autonomous robotic system for anterior immediate and delayed implant placement.

Methods

This retrospective study included patients who underwent anterior dental implant surgery from September 2022 to March 2025 using an autonomous robotic system. Osteotomies performed with the autonomous robotic system in this study were modified by using precision and side-cutting drills, along with repeated lifting of drills to minimize deviations. Linear and angular deviations in two- and three-dimensional space were assessed by matching preoperative planning with postoperative cone beam computed tomography. Postoperative pain and surgical satisfaction were recorded using a 100-mm visual analog scale. The Shapiro–Wilk test, Student's t-test, Mann–Whitney U-test, Pearson's Chi-Square test, and Fisher's exact test were used, and p < 0.05 was considered statistically significant.

Results

This retrospective study included 53 patients (65 implants) who underwent anterior dental implant surgery with the autonomous robotic system (immediate implant placement group: 19 patients, 21 implants; delayed implant placement group: 34 patients, 44 implants). Comparison of deviations in immediate and delayed implantation using the autonomous robotic system showed a mean (± SD) coronal deviation of 0.57 ± 0.19 mm versus 0.49 ± 0.20 mm (p = 0.129), a mean apical deviation of 0.57 ± 0.19 mm versus 0.52 ± 0.21 mm (p = 0.373), and a mean angular deviation of 0.53° ± 0.18° versus 0.61° ± 0.28° (p = 0.742). Postoperative pain and surgical satisfaction were not significantly different between the two groups (p > 0.05).

Conclusions

The autonomous robotic system demonstrated high and comparable accuracy in both anterior immediate and delayed implantation, with overall patient satisfaction. This could reduce the technical sensitivity of anterior immediate implant placement, enhance precision, and broaden the clinical applications of the autonomous robotic system.

Objetives

This study aimed to explore the reliability of cone beam computed tomography (CBCT) in evaluating the quality of augmented bone after lateral sinus floor elevation (LSFE) with xenografts.

Materials and Methods

Thirty-six patients with lost maxillary molars were included, with half of whom received LSFE with xenografts and staged implant placement, and the other half showed no vertical bone defects and underwent implant placement directly. A total of 36 implants were included, with 18 implants in each group. A CBCT exam was taken before implant placement to acquire data on mineral quality at the future implant site, including bone mineral density (BMD), various microstructure indices, and gray values (GVs) within different threshold ranges. Augmented bone biopsies were collected during implant preparation. The microstructure indices and histological characteristics of the biopsies were evaluated by micro computed tomography (μCT) and histological staining. An implant-oriented volume of interest for CBCT analysis was established to co-locate the CBCT-measured data and the biopsy-related data using 3DSlicer. A Spearman rank correlation test was used to analyze the relationship between CBCT-measured data and the biopsy-related data.

Results

μCT-measured microstructure indices of the augmented bone (BV/TV and Tb.Th) were significantly correlated with new bone area (BV/TV, p = 0.035, r = 0.498; Tb.Th, p = 0.027, r = 0.520). No correlation was found between the CBCT-measured and μCT-measured microstructure indices. CBCT-measured BMD and microstructure indices hardly showed any correlation with histological indices (p > 0.05). When the threshold was set from 0 to 50, the mean GVs were significantly, positively correlated with new bone area (p = 0.041, r = 0.486), and bone substitute area was positively correlated to the mean GVs of higher threshold (range 60–255, p = 0.048, r = 0.472; range 70–255, p = 0.009, r = 0.593).

Conclusions

CBCT without bone substitute segmentation was not reliable for evaluating the quality of xenogenic augmented bone after LSFE. The influence of the xenogenic substitute on CBCT analysis can be reduced by setting a low GV threshold. The bone substitute segmentation strategy may present a new way to increase the reliability of CBCT in evaluating xenogenic augmented bone.