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Materials (Basel, Switzerland) May 2024Stress distribution and its magnitude during loading heavily influence the osseointegration of dental implants. Currently, no high-resolution, three-dimensional method...
Stress distribution and its magnitude during loading heavily influence the osseointegration of dental implants. Currently, no high-resolution, three-dimensional method of directly measuring these biomechanical processes in the peri-implant bone is available. The aim of this study was to measure the influence of different implant materials on stress distribution in the peri-implant bone. Using the three-dimensional ARAMIS camera system, surface strain in the peri-implant bone area was compared under simulated masticatory forces of 300 N in axial and non-axial directions for titanium implants and zirconia implants. The investigated titanium implants led to a more homogeneous stress distribution than the investigated zirconia implants. Non-axial forces led to greater surface strain on the peri-implant bone than axial forces. Thus, the implant material, implant system, and direction of force could have a significant influence on biomechanical processes and osseointegration within the peri-implant bone.
PubMed: 38730967
DOI: 10.3390/ma17092161 -
Materials (Basel, Switzerland) May 2024Bone substitutes are ideally biocompatible, osteoconductive, degradable and defect-specific and provide mechanical stability. Magnesium phosphate cements (MPCs) offer...
Bone substitutes are ideally biocompatible, osteoconductive, degradable and defect-specific and provide mechanical stability. Magnesium phosphate cements (MPCs) offer high initial stability and faster degradation compared to the well-researched calcium phosphate cements (CPCs). Calcium magnesium phosphate cements (CMPCs) should combine the properties of both and have so far shown promising results. The present study aimed to investigate and compare the degradation and osseointegration behavior of 3D powder-printed wedges of CMPC and MPC in vivo. The wedges were post-treated with phosphoric acid (CMPC) and diammonium hydrogen phosphate (MPC) and implanted in a partially loaded defect model in the proximal rabbit tibia. The evaluation included clinical, in vivo µ-CT and X-ray examinations, histology, energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) for up to 30 weeks. SEM analysis revealed a zone of unreacted material in the MPC, indicating the need to optimize the manufacturing and post-treatment process. However, all materials showed excellent biocompatibility and mechanical stability. After 24 weeks, they were almost completely degraded. The slower degradation rate of the CMPC corresponded more favorably to the bone growth rate compared to the MPC. Due to the promising results of the CMPC in this study, it should be further investigated, for example in defect models with higher load.
PubMed: 38730942
DOI: 10.3390/ma17092136 -
Journal of Periodontal & Implant Science Feb 2024Bone quality is one of the most important clinical factors for the primary stability and successful osseointegration of dental implants. This preliminary pilot study...
Deep learning to assess bone quality from panoramic radiographs: the feasibility of clinical application through comparison with an implant surgeon and cone-beam computed tomography.
PURPOSE
Bone quality is one of the most important clinical factors for the primary stability and successful osseointegration of dental implants. This preliminary pilot study aimed to evaluate the clinical applicability of deep learning (DL) for assessing bone quality using panoramic (PA) radiographs compared with an implant surgeon's subjective tactile sense and cone-beam computed tomography (CBCT) values.
METHODS
In total, PA images of 2,270 edentulous sites for implant placement were selected, and the corresponding CBCT relative gray value measurements and bone quality classification were performed using 3-dimensional dental image analysis software. Based on the pre-trained and fine-tuned ResNet-50 architecture, the bone quality classification of PA images was classified into 4 levels, from D1 to D4, and Spearman correlation analyses were performed with the implant surgeon's tactile sense and CBCT values.
RESULTS
The classification accuracy of DL was evaluated using a test dataset comprising 454 cropped PA images, and it achieved an area under the receiving characteristic curve of 0.762 (95% confidence interval [CI], 0.714-0.810). Spearman correlation analysis of bone quality showed significant positive correlations with the CBCT classification (=0.702; 95% CI, 0.651-0.747; <0.001) and the surgeon's tactile sense (=0.658; 95% CI, 0.600-0.708, <0.001) versus the DL classification.
CONCLUSIONS
DL classification using PA images showed a significant and consistent correlation with CBCT classification and the surgeon's tactile sense in classifying the bone quality at the implant placement site. Further research based on high-quality quantitative datasets is essential to increase the reliability and validity of this method for actual clinical applications.
PubMed: 38725425
DOI: 10.5051/jpis.2302880144 -
International Journal of Implant... May 2024The objective of the present study was to ascertain the effect of immediate occlusal loading after implant placement on osseointegration and the micro/nanostructure of...
PURPOSE
The objective of the present study was to ascertain the effect of immediate occlusal loading after implant placement on osseointegration and the micro/nanostructure of the surrounding bone.
METHODS
After extraction of a rat maxillary right second molar, an implant was placed immediately with initial fixation (2 N< ). The implants were placed to avoid occlusal loading due to mastication, and in the loaded group, a superstructure was fabricated and subjected to occlusal loading. Bone morphometry, collagen fiber anisotropy, and biological apatite (BAp) crystallite alignment were quantitatively evaluated in both groups after extraction and fixation of the jaw bone at Days 7 and 21 after surgery.
RESULTS
Osseointegration was observed in both groups. Bone morphometry showed significant differences in bone volume, trabecular number, trabecular thickness and bone mineral density (BMD) at Days 21 postoperatively (P < 0.05). A significant difference was also found in the trabecular separation at Days 7 postoperatively (P < 0.05). In the evaluation of collagen fiber anisotropy, collagen fiber bundles running differently from the existing bone were observed in both groups. In terms of BAp crystallite alignment, a specific structure was observed in the reconstructed new bone after implantation, and preferential orientation of BAp crystallite alignment was observed in the longitudinal direction of the implants in the Day 21 postoperative loaded group.
CONCLUSION
When sufficient initial fixation is achieved at the time of dental implant placement, then the applied masticatory load may contribute to rapidly achieving not only bone volume, but also adequate bone quality after implant placement.
Topics: Animals; Rats; Osseointegration; Immediate Dental Implant Loading; Male; Bone Density; Dental Implants; Rats, Wistar; Maxilla; Collagen; X-Ray Microtomography
PubMed: 38722448
DOI: 10.1186/s40729-024-00538-x -
Acta Biochimica Polonica 2024The study aimed to determine the osteointegration markers after dental implantation and evaluate their predictive value. The study was performed on 60 practically...
The study aimed to determine the osteointegration markers after dental implantation and evaluate their predictive value. The study was performed on 60 practically healthy persons who needed teeth rehabilitation using dental implants. The conical-shaped implants (CI) and hexagonal implants (HI) were used. The content of Osteopontin (OPN), Osteocalcin (OC), Alkaline Phosphatase (ALP), Osteoprotegerin (OPG), and nitric oxide (NO) was determined in patients' gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF), collected 1, 3, and 6 months after implantation. During the 3-6 months of observation level of OPN increased in patients with CIs (<50 years > 50 years) and HIs (<50 years) (CI: <50 years F = 36.457, < 0.001; >50 years F = 30.104, < 0.001; HI < 50 years F = 2.246, < 0.001), ALP increased in patients with CIs (<50 years: F = 19.58, < 0.001; >50 years: F = 12.01; = 0.001) and HIs (<50 years) (F = 18.51, < 0.001), OC increased in patients <50 years (CI: F = 33.72, < 0.001; HI: F = 55.57, < 0.001), but in patients >50 years - on the 3 days month (CI: F = 18.82, < 0.001; HI: F = 26.26, < 0.001), but sharply decreased at the end of sixth month. OPG increased during 1-3 months of the observation in patients <50 years (CI: F = 4.63, = 0.037; HI: F = 2.8927, = 0.046), but at the end of the sixth month returned to the initial level; NO content in PISF increased in patients with CI (>50 years) during 1-6 months of the observation (F = 27.657, < 0.001). During the post-implantation period, age-related differences in osteointegration were observed. Patients <50 years old had relatively high levels of OPN, ALP, OC, and OPG in PISF, resulting in less alveolar bone destruction around dental implants and more intensive osteointegration. These indicators may be used as biological markers for monitoring implant healing. The process of osseointegration was more intense in CIs due to their comparatively high mechanical loading.
Topics: Humans; Middle Aged; Biomarkers; Female; Male; Osteoprotegerin; Gingival Crevicular Fluid; Alkaline Phosphatase; Osseointegration; Osteocalcin; Adult; Osteopontin; Prognosis; Dental Implants; Nitric Oxide; Dental Implantation; Time Factors
PubMed: 38721304
DOI: 10.3389/abp.2024.12433 -
Cureus Apr 2024Reducing the healing period after surgical placement of dental implants can facilitate the loading of dental prostheses.
INTRODUCTION
Reducing the healing period after surgical placement of dental implants can facilitate the loading of dental prostheses.
AIM
The aim is to compare the osteogenic potential of unmodified titanium disks with titanium disks that were surface-modified or hydrogel-coated.
MATERIALS AND METHODOLOGY
One hundred eight titanium disks (Ø6 × 2-mm) were divided into three groups: (1) unmodified titanium as control (Ti-C); (2) sandblasted and acid-etched (Ti-SLA), and (3) coated with tamarind kernel polysaccharide hydrogel grafted with acrylic acid (Ti-TKP-AA). The osteogenic potential and cytotoxic effect of various groups of titanium were compared using human osteoblasts Saos-2. The surface topography of the titanium disks and morphology of osteoblasts grown on disks were investigated by scanning electron microscopy (n = 3). Cell attachment to the disks and actin expression intensity were investigated by confocal imaging (n = 3). Cytotoxicity was quantified by cell viability assay (n = 9). Osteoblast maturation was determined by alkaline phosphatase assay (n = 9). Cell mineralization was quantified by Alizarin red staining (n = 9). One-way analysis of variance followed by Tukey's multiple comparisons test was used for intergroup comparisons (= 0.05).
RESULTS
The surface modifications on Ti-SLA and Ti-TKP-AA support better morphology and proliferation of osteoblasts than Ti-C (P< 0.001) and significantly higher levels of actin cytoskeleton accumulation (P< 0.0001). Ti-TKP-AA showed a significantly higher maturation rate than Ti-C (P< 0.001). Ti-TKP-AA showed > twofold increased mineralization than Ti-C and Ti-SLA (P< 0.001).
CONCLUSIONS
TKP-AA hydrogel-coated titanium promotes faster osteoblast proliferation, maturation, and mineralization than SLA-treated or untreated titanium. These advantages can be explored for achieving early osseointegration and prosthetic loading of titanium dental implants.
PubMed: 38721174
DOI: 10.7759/cureus.57785 -
Stem Cell Research & Therapy May 2024Biomaterials used in bone tissue engineering must fulfill the requirements of osteoconduction, osteoinduction, and osseointegration. However, biomaterials with good...
BACKGROUND
Biomaterials used in bone tissue engineering must fulfill the requirements of osteoconduction, osteoinduction, and osseointegration. However, biomaterials with good osteoconductive properties face several challenges, including inadequate vascularization, limited osteoinduction and barrier ability, as well as the potential to trigger immune and inflammatory responses. Therefore, there is an urgent need to develop guided bone regeneration membranes as a crucial component of tissue engineering strategies for repairing bone defects.
METHODS
The mZIF-8/PLA membrane was prepared using electrospinning technology and simulated body fluid external mineralization method. Its ability to induce biomimetic mineralization was evaluated through TEM, EDS, XRD, FT-IR, zeta potential, and wettability techniques. The biocompatibility, osteoinduction properties, and osteo-immunomodulatory effects of the mZIF-8/PLA membrane were comprehensively evaluated by examining cell behaviors of surface-seeded BMSCs and macrophages, as well as the regulation of cellular genes and protein levels using PCR and WB. In vivo, the mZIF-8/PLA membrane's potential to promote bone regeneration and angiogenesis was assessed through Micro-CT and immunohistochemical staining.
RESULTS
The mineralized deposition enhances hydrophilicity and cell compatibility of mZIF-8/PLA membrane. mZIF-8/PLA membrane promotes up-regulation of osteogenesis and angiogenesis related factors in BMSCs. Moreover, it induces the polarization of macrophages towards the M2 phenotype and modulates the local immune microenvironment. After 4-weeks of implantation, the mZIF-8/PLA membrane successfully bridges critical bone defects and almost completely repairs the defect area after 12-weeks, while significantly improving the strength and vascularization of new bone.
CONCLUSIONS
The mZIF-8/PLA membrane with dual osteoconductive and immunomodulatory abilities could pave new research paths for bone tissue engineering.
Topics: Bone Regeneration; Animals; Osteogenesis; Tissue Engineering; Biocompatible Materials; Mice; Mesenchymal Stem Cells; Membranes, Artificial; Guided Tissue Regeneration; Tissue Scaffolds; Polyesters; Rats
PubMed: 38715130
DOI: 10.1186/s13287-024-03745-w -
Dental Materials : Official Publication... Jun 2024Nanotechnology is constantly advancing in dental science, progressing several features aimed at improving dental implants. An alternative for surface treatment of dental... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
Nanotechnology is constantly advancing in dental science, progressing several features aimed at improving dental implants. An alternative for surface treatment of dental implants is electrochemical anodization, which may generate a nanotubular surface (TiO nanotubes) with antibacterial potential and osteoinductive features. This systematic review and meta-analysis aims to elucidate the possible antibacterial properties of the surface in question compared to the untreated titanium surface.
SOURCES
For that purpose, was performed a systematic search on the bases PubMed, Lilacs, Embase, Web Of Science, Cinahl, and Cochrane Central, as well as, manual searches and gray literature.
STUDY SELECTION
The searches resulted in 742 articles, of which 156 followed for full-text reading. Then, 37 were included in the systematic review and 8 were included in meta-analysis.
RESULTS
Fifteen studies revealed significant antibacterial protection using TiO nanotube surfaces, while 15 studies found no statistical difference between control and nanotextured surfaces. Meta-analysis of in vitro studies demonstrated relevant bacterial reduction only for studies investigating Staphylococcus aureus in a period of 6 h. Meta-analysis of in vivo studies revealed three times lower bacterial adhesion and proliferation on TiO nanotube surfaces.
CONCLUSIONS
TiO nanotube topography as a surface for dental implants in preclinical research has demonstrated a positive relationship with antibacterial properties, nevertheless, factors such as anodization protocols, bacteria strains, and mono-culture methods should be taken into consideration, consequently, further studies are necessary to promote clinical translatability.
Topics: Titanium; Nanotubes; Dental Implants; Surface Properties; Anti-Bacterial Agents; Bacterial Adhesion; Humans; Staphylococcus aureus
PubMed: 38714394
DOI: 10.1016/j.dental.2024.04.009 -
Bioinformation 2024The distribution of stress on short platform switched dental implants is of interest. Hence, the mandibular posterior molar area was modelled using a three-dimensional...
The distribution of stress on short platform switched dental implants is of interest. Hence, the mandibular posterior molar area was modelled using a three-dimensional finite element method (FEM) with a continuous 1.5 mm cortical bone thickness and an inner cancellous bone core. The implants used in the study were 5 mm long, 4.5 mm wide and 3.5 mm wide at the abutments. 120 N of force was applied in both the vertical and oblique (20° and 35°) directions to create a realistic simulation. ANSYS Workbench was generated for each model. Von Mises stress was assessed in the cortical and cancellous bones at varying depths. Ten noded tetrahedron elements with three degrees of freedom per node were employed to interpret translations on the x, y, and z axes. The stress-based biomechanical behaviour of platform switched short osseo-integrated implants varied across all 5 positions in FEM simulations, based on the depth of implant placement, the direction of applied force, and the shape of the bone. Data shows that opposite forces to the vertical forces caused more damage. Thus, the implantation of subcrestal implants resulted in reduced stress on the cortical and cancellous bone.
PubMed: 38712001
DOI: 10.6026/973206300200248 -
Materials Today. Bio Jun 2024Periprosthetic infection and mechanical loosening are two leading causes of implant failure in orthopedic surgery that have devastating consequences for patients both...
Periprosthetic infection and mechanical loosening are two leading causes of implant failure in orthopedic surgery that have devastating consequences for patients both physically and financially. Hence, advanced prostheses to simultaneously prevent periprosthetic infection and promote osseointegration are highly desired to achieve long-term success in orthopedics. In this study, we proposed a multifunctional three-dimensional printed porous titanium alloy prosthesis coated with imidazolium ionic liquid. The imidazolium ionic liquid coating exhibited excellent bacterial recruitment property and near-infrared (NIR) triggered photothermal bactericidal activity, enabling the prosthesis to effectively trap bacteria in its vicinity and kill them remotely via tissue-penetrating NIR irradiation. anti-infection and osseointegration investigations in infected animal models confirmed that our antibacterial prosthesis could provide long-term and sustainable prevention against periprosthetic infection, while promoting osseointegration simultaneously. It is expected to accelerate the development of next-generation prostheses and improve patient outcomes after prosthesis implantation.
PubMed: 38711938
DOI: 10.1016/j.mtbio.2024.101076