Clinical Implant Dentistry and Related Research最新文献

Objectives

To compare the efficacy of the connective tissue graft (SCTG) and the collagen matrix (VXCM) in terms of soft tissue gain at the buccal site around a single implant.

Methods

The study was designed as a randomized, controlled clinical trial. This trial was registered in ClinicalTrial.gov with the identifier NCT05870774 and is accessible under the following link: https://clinicaltrials.gov/study/NCT05870774?term=NCT05870774&rank=1. This clinical trial was not registered prior to participant recruitment and randomization. Patients with a single tooth gap and horizontal soft tissue thickness deficiency were enrolled in the study. Sites were randomly allocated to the control (SCTG) or test group (VXCM: Geistlich Fibro-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) to augment buccal soft tissue thickness. The primary outcome was soft tissue gain 3 months post-op. Secondary outcomes included soft tissue gain 6 months post-op, the pink aesthetic score (PES), and patient-reported outcome measures (PROMs).

Results

Patients' recruitment started on 28 October 2021 and ended on 25 December 2022. Thirty-two patients were enrolled and subjected to intervention. Sixteen patients were included per group. Three months post-op, soft tissue gain at the buccal site was 1.77 ± 0.61 mm in the VXCM group and 1.26 ± 0.41 mm in the SCTG group (p = 0.0003). Six months post-op, soft tissue gain was 1.11 ± 0.44 mm in the VXCM group and 1.43 ± 0.81 mm in the SCTG group (p = 0.0459). PROMs, including pain perception, favored the VXCM group. SCTG demonstrated favored results in PES.

Conclusion

SCTG remains the gold standard for increasing soft tissue thickness in terms of the clinical result.

Introduction

Alveolar ridge augmentation has been one of the most accepted treatments for restoring bone volume. Various products are available in particle forms, which have limitations, especially related to controlling the expected volume gain. A prefabricated computer-aided design and computer-aided manufacturing (CAD-CAM) allogenic bone block could provide a good alternative.

Materials and Methods

A split-mouth randomized clinical trial included 10 patients with the bilateral posterior atrophic mandible (20 sides), who were randomly assigned to two groups with an allocation ratio of 1:1. Group I: the ridge was augmented using prefabricated CAD-CAM allogenic bone block hydrated using hyaluronic acid, and group II was hydrated using saline. Blinding was limited to the patients and the investigator responsible for data analysis (double blinding). Six months after grafting surgery, a core biopsy was taken for histological analysis, and implants were inserted into the augmented ridge. The amount of bone gain was evaluated radiographically using CBCT.

Results

All ridges in both groups revealed a successful bone gain in CBCT. However, the mean bone gain in group I (3.975 ± 0.31) was significantly higher than in group II (2.497 ± 0.66). Histologically, both groups showed osteointegration and new bone formation, with group I being superior. VEGF, OPN, and Cox 2 expressions were more intense in group I than in group II. The histomorphometric analysis revealed that group I had a considerably higher surface area of new bone formation than group II (p-value < 0.001). Immunohistochemical staining for VEGF revealed a significant difference between groups I (15.04 ± 0.47) and II (11.41 ± 0.54).

Conclusion

Within the limitations of this study, the addition of HA to prefabricated CAD-CAM allogenic block enhanced its osteogenic properties and guaranteed adequate integration of the graft for implant insertion.

Trial Registration

This clinical trial was not registered before the participants' recruitment and randomization (https://clinicaltrials.gov/study/NCT06395818).

Objective

This study aimed to compare the clinical effects of implants placed in sites with a transcrestal sinus floor elevation (TSFE) featuring a residual bone height (RBH) of ≤ 5 mm, without Schneiderian membrane perforations, to those in sites where a lateral window approach was utilized to repair perforations that occurred during TSFE.

Methods

A total of 104 implants in 80 patients (80 sinuses) with RBH ≤ 5 mm who had undergone TSFE with simultaneous implant placement were included in this retrospective study. The implants were categorized into two groups based on whether the Schneiderian membrane was perforated, and the lateral window technique for sinus floor elevation (LSFE) was utilized to repair perforations that occurred during the TSFE procedure. The early implant loss, endo-sinus bone gain (ESBG), and implant apical bone resorption (ABR) were used to assess new bone formation between the non-perforated and the perforated groups.

Results

The non-perforation group consisted of 89 implants in 69 patients (69 sinuses), whereas the perforated group included 15 implants in 11 patients (11 sinuses). No early implant loss or postoperative complications were observed in either group during the first 6 months following implant installation. The ESBG was (5.83 ± 2.06) mm for the non-perforation group and (7.76 ± 1.63) mm for the perforation-repaired group (p < 0.001). A linear mixed model indicated that group (β = 2.41, 95% CI = 1.49, 3.33, p < 0.001) and RBH (β = −0.53, 95% CI = −0.80, −0.27, p < 0.001) significantly influenced ESBG. The ABR between the non-perforation and perforated group has no statistically significant difference (β = 0.84, 95% CI = −0.41, 2.08, p = 0.185).

Conclusion

Repairing Schneiderian membrane perforations that occur during TSFE in cases with RBH ≤ 5 mm, using the lateral window technique, leads to ideal internal radiographic bone augmentation volume maintenance in the maxillary sinus compared to cases without perforation; no significant difference in early implant loss was observed.

Trial Registration: Clinical Trial Registry: (ChiCTR2200062886)

Aim

To compare the linear and angular deviations of conventional implant (CI) and digital implant (DI) impression techniques in edentulous jaws with four or six implants.

Materials and Methods

Twenty participants (12 men, 8 women; mean age 58.6 years) with complete edentulous maxillary (n = 8) or mandibular (n = 12) arches were included. Each patient received four or six dental implants (Straumann BLX). Both CI and DI were performed using randomized sequences. Linear and angular deviations were measured between the reference scan (coordinated measuring machine) and the CI (desktop scanner) and DI (intraoral scanner, IOS) using CATIA software (Dassault Systèmes). Framework passivity was evaluated using the Sheffield one-screw test. The Shapiro–Wilk test determined data normality (p < 0.05), and nonparametric statistical tests were applied using statistical software.

Results

Descriptive statistics showed a mean linear discrepancy of 29.05 (84.80 μm) for CI and 6.95 (154.10 μm) for DI, with angular deviations of 0.06° (0.36°) for CI and 0.05° (1.40°) for DI. No statistically significant differences were found in linear (p = 0.38) or angular (p = 0.12) measurements between CI and DI. Framework passivity testing showed that both techniques achieved passive fit in 17 out of 20 cases (85%), with the reference scan achieving passivity in 18 (90%) cases. Distal implants, particularly in the upper jaw, exhibited greater discrepancies, but none were statistically significant.

Conclusions

No significant differences in trueness were found between CI and DI techniques. Both methods demonstrated comparable trueness and framework passivity, supporting the use of IOS as a reliable alternative to CI in edentulous jaws with multiple implants.

Aim

To evaluate the clinical and radiographic outcomes of non-surgical treatment followed by either reconstructive therapy or supportive care with no further surgical measures for the treatment of peri-implantitis intra-bony defects.

Materials and Methods

This randomized clinical trial included patients diagnosed with peri-implantitis exhibiting intrabony defects (≥ 3 mm). All 36 patients received a standardized peri-implant non-surgical therapy. Patients who did not demonstrate disease resolution based on clinical and radiographic re-evaluation were randomized into two groups. The test group received reconstructive therapy [reconstructive group (RG)] while the control group received no additional treatment except supportive care every 3 months [non-reconstructive group (NRG)]. The primary outcome was the mean radiographic bone change at 12 months; the difference between groups was assessed using Mann–Whitney two-sample tests. Clinical and radiographic parameters were recorded at the initial examination and at 3, 6, and 12 months. Also, patient-reported outcomes were assessed.

Results

Overall, 34 patients (implants = 34) completed the study. Both therapies resulted in significant clinical and radiographic changes after 12 months. Disease resolution was achieved in 8 (44.4%) NRG patients and 7 (43.8%) RG patients (p ≥ 0.05) with no significant differences between groups. The groups displayed no significant differences in clinical variables, but radiographic bone fill was ~3× greater in the RG group at 12 months [1.21 (SD 0.92) mm versus 0.36 (SD 0.59) mm], demonstrating statistical significance between the tested groups.

Conclusions

The tested therapeutic modalities demonstrated equal disease resolution. Nevertheless, the marginal bone level gain was significantly greater for sites subjected to reconstructive surgical therapy (NCT05168891—This clinical trial was not registered prior to participant recruitment and randomization).

Objectives

This study aimed to identify risk factors associated with early implant failure in the anterior maxillary and mandibular regions.

Materials and Methods

A total of 2023 patients with 2620 implants placed in the maxillary and mandibular anterior regions between January 2020 and June 2023 were included in this study. Clinical and radiographic data were extracted from medical records and imaging software. In organizing the information, 19 variables were categorized into patient-related factors (gender, age, periodontitis, reasons for tooth loss, bone quality, and penicillin allergy), implant-related factors (implant system, bone level/soft tissue level, diameter, and length), and surgical factors (jaw position, placement timing, bone grafting, bone compression/splitting surgery, concentrated growth factors (CGFs), bone graft materials, barrier membrane, torque, and healing style). Univariate and multivariate Cox proportional hazards regression models were used to identify significant risk factors for early failure.

Results

The cumulative survival rate (CSR) of all implants after a 0- to 43-month observation period was 95.6% (95% confidence interval [CI]: 94.8%–96.4%). Independent risk factors for early implant failure included non-submerged healing (hazard ratio [HR] = 3.000, 95% CI = 1.712–5.256), torque < 30 N/cm (HR = 13.193, 95% CI = 8.439–20.626), and Type I bone quality (HR = 3.220, 95% CI = 1.413–7.342) (all p < 0.05). Conversely, bone compression or splitting surgery was identified as a protective factor (HR = 0.344, 95% CI = 0.186–0.634). No significant associations were observed for age, reasons for tooth loss, penicillin allergy, use of CGF, or implant characteristics (location, type, length, and diameter).

Conclusion

After 0–43 months of observation, the CSR for 2620 implants placed in 2023 patients was 95.6% (95% CI = 94.8%–96.4%). Torque < 30 N/cm, non-submerged healing, and Type I bone quality were considered independent risk factors for early implant failure in the anterior region.

Introduction

The present study aimed to evaluate and to compare the influence of anatomical variables such as sinus width (SW), inner maxillary sinus contour length (IMSCL), and residual ridge height (RRH) on new bone formation (%NBF) for deproteinized porcine (DPBM) and bovine bone mineral (DBBM) used for lateral window sinus augmentation (LWSA) grafting.

Material and Methods

For LWSA groups grafted either with DPBM (n = 10) or DBBM (n = 13) a linear- as well as a multivariate-regression analysis was conducted between measured %NBF and radiographically retrospectively assessed anatomical variables (SW/IMSCL/RRH). Correlations as well as regression coefficients (R²) were calculated, evaluating the influence of anatomical variables on %NBF with differentiation between both xenogenic graft materials used.

Results

With no differences for patient-epidemiologic data, for anatomical variables as well as for surgical- and patient-related risk factors, comparison between the two LWSA groups was possible. The linear-regression analysis provided significant correlations between histomorphometrically evaluated %NBF and SW (DPBM: r = −0.660, p = 0.038; DBBM: r = −0.614, p = 0.026) as well as between %NBF and IMSCL (DPBM: r = −0.737; p = 0.015, DBBM: r = −0.573, p = 0.041), but not for RRH. Between SW/IMSCL/RRH and %NBF, regression-coefficients-(R²) of 0.435/0.543/0.258 using DPBM and R² of 0.377/0.328/0.053 using DBBM represented evidently higher influences of anatomical structures when porcine graft material was applied. The multivariate-regression analysis confirmed the different influence between various xenogenic graft materials on % NBF as well with a pronounced effect for porcine material (DPBM: R² = 0.591 [59.1%] vs. DBBM: R² = 0.314 [31.4%]).

Conclusion

In LWSA, anatomical structures such as SW and IMSCL significantly affect new bone formation, though with varying effects for different xenogenic (porcine vs. bovine) bone mineral graft materials used.