Search Results (575)

Biopolymers have emerged as a transformative class of materials that reconcile high-performance functionality with environmental stewardship. Their inherent capacity for controlled degradation and biocompatibility has driven rapid advancements across electronics, sensing, actuation, and healthcare. In flexible electronics, these polymers serve as substrates, dielectrics, and conductive composites that enable transient devices, reducing electronic waste without compromising electrical performance. Within sensing and actuation, biodegradable polymer matrices facilitate the development of fully resorbable biosensors and soft actuators. These systems harness tailored degradation kinetics to achieve temporal control over signal transduction and mechanical response, unlocking applications in in vivo monitoring and on-demand drug delivery. In healthcare, biodegradable polymers underpin novel approaches in tissue engineering, wound healing, and bioresorbable implants. Their tunable chemical architectures and processing versatility allow for precise regulation of mechanical properties, degradation rates, and therapeutic payloads, fostering seamless integration with biological environments. The convergence of these emerging applications underscores the pivotal role of biodegradable polymers in advancing sustainable technology and personalized medicine. Continued interdisciplinary research into polymer design, processing strategies, and integration techniques will accelerate commercialization and broaden the impact of these lower eCO₂ value materials across diverse sectors. This perspective article comments on the innovation in these sectors that go beyond the applications of biodegradable materials in packaging applications. Full article

Background/Objectives: Vertical ridge augmentation remains a challenging procedure in alveolar bone reconstruction, with existing techniques often limited by surgical complexity, graft instability, and high resorption rates. This study evaluates the clinical and histological outcomes of a novel vertical ridge augmentation technique using a wide-head tenting pole screw (WHTPS) combined with sticky bone graft material. Methods: Five patients with vertical bone deficiencies (6–10 mm) in the maxilla or mandible underwent augmentation using a single WHTPS (rectangular or round wide-head type). Sticky bone was prepared using autologous tooth bone, allografts, or xenografts, combined with fibrin glue and covered with concentrated growth factor (CGF) membranes and/or resorbable collagen membranes. After 5–6 months of healing, the WHTPS was removed, and bone biopsies were taken for histological analysis. Results: Radiographic and histological evaluations confirmed successful ridge augmentation in all cases. Newly formed bone ranged from 21.2% to 57.5%. All patients proceeded to implant placement without complications. Radiographic, clinical, and histological assessments consistently showed that new bone formation extended up to the level of the screw head, indicating complete vertical fill of the augmented space. Histology showed well-integrated, mineralized bone with no signs of inflammation. The wide-head tenting pole screw was observed to support stable space maintenance and facilitate surgical handling and favorable outcomes in vertical ridge augmentation. Conclusions: In this case series, a single wide-head tenting pole screw appeared sufficient to maintain space and resist soft tissue pressure in wide alveolar bone defects during healing. This case series suggests that the wide-head tenting pole screw technique may be a feasible option for managing severe alveolar bone deficiencies. Full article

Background and Objectives: In vitro evaluation of macro and microscopic features of five resorbable barrier membranes used for Guided Bone Regeneration (GBR) in oral hard tissue surgery. Materials and Methods: Five different resorbable barrier membranes were analyzed by optical microscopy and scanning electron microscopy (SEM). For each sample, surface appearance, the presence and size of ridges and depressions, number of layers, and the inner structure were recorded. Each membrane was cut into 1 × 1 cm squares to determine mass, density and thickness. In addition, an EDX microanalysis was performed. Results: Under optical microscopy, all membranes appeared rough, with ridges and depressions. In cross-section, only Sample 2 presented true stratification. On SEM, most membranes showed a three-dimensional collagen fiber architecture. Sample 3, a sheet of collagenated equine bone, differed accordingly. EDX spectra showed broadly overlapping elemental composition, characterized by N, O and C. The mass depends on the composition: bone-containing membranes weighed more; those composed predominantly of collagen weighed less. Conclusions: Pore size, surface density and roughness, and the type of cross-linking can influence cell interaction and may lead to different regenerative scenarios, potentially improving the quality and timing of tissue regeneration. Membrane selection should be dictated by the clinical scenario, prioritizing properties most advantageous for the defect. Full article

Notably, the widespread ubiquity of arsenic and graphene oxide in the environment validates the occurrence of their co-exposure, posing significant threats to target organisms, including humans. Herein, prepuberty, puberty, and maturity were investigated using anogenital distance, vaginal opening, first estrus, reproductive hormone profiles, cyclicity, sexual behaviour and pregnancy outcomes to assess the impact of exposure to arsenic and/or graphene oxide on the puberty of offspring female rats after maternal exposure during gestation and lactation periods. Zero-day pregnant Sprague Dawley females were randomly divided into four groups, each receiving a different treatment via drinking water from gestation day 0 to postnatal day 21: control group (CON, drinking water); arsenic group (ARS, 10 mg/L sodium arsenite); graphene oxide group (GOX, 0.5 mg/mL); and co-exposure group (ARS + GOX; 10 mg/L of arsenic combined with 0.5 mg/mL of graphene oxide). Individually or combined, arsenic and graphene oxide exposure increase the sexual retardation and female masculinization, as evidenced by a significant increase in anogenital distance, delay in the first estrus cycle, and prolongation in the timing of the vaginal opening. At maturity, the offspring exhibited a significant elevation of testosterone and a significant decrease in estradiol. Offspring females showed inhibited receptivity to their male mates, indicated by lower lordosis quotient and intensity. Additionally, there was an increase in the number of estrous cycles but a decrease in their duration. Moreover, an increase in implantation loss and the number of resorbed embryos, along with a reduction in viable fetuses. In conclusion, reproductive deterioration was more significant in the offspring exposed to combined arsenic and graphene oxide compared to those exposed to ARS or GOX alone, indicating that arsenic exposure is exacerbated when combined with graphene oxide during the experimental episode. Full article

Background: The aim of this experimental pilot study was to evaluate the effect of pore volume and material composition on bone ingrowth into a resorbable poly-L-lactide-CaCO₃/CaP scaffold. Methods: Cylindric scaffolds of 7 mm diameter and 5 mm height and two different degrees of porosity were produced using selective laser sintering of poly-L-lactide-powder containing 24% CaCO₃ spherulites with and without surface modification with 4% CaP. Six minipigs received the four types of macroporous cylindrical scaffolds, inserted press fit into trephine defects of the tibial metaphyses, and left to heal for 4 and 13 weeks in three animals each. The specimens were evaluated using µCT for pore volume fill, and histomorphometry for bone formation and immunohistochemistry for expression of osteocalcin. Results: After 4 weeks, newly formed bone ranged from 2.73 mm² to 5.28 mm² mean total area. Mean pore volume fill varied between 12.25% and 20.35% and the average level of osteocalcin expression ranged from 2.49 mm² to 4.48 mm² mean total area. No significant differences were found between the different scaffolds. After 13 weeks, bone formation and pore fill volume had significantly increased in all scaffold groups up to a mean value of 14.79 mm² and 96.04%, respectively. Again, differences between the groups were not significant. Conclusions: The tested SLS produced scaffolds allowed for bone ingrowth, almost completely filling the pore volume after 13 weeks. Newly formed bone was in direct contact with the scaffold walls. Differences in pore volume did not account for significant differences in bone formation inside the scaffolds. The addition of CaP likewise did not lead to increased bone formation, most likely due to low availability of CaP to the biological environment. Full article

The research of biomaterials is an area of significant interest in the biomedical field, and the present study investigates how the strontium (Sr) concentration influences the microstructure, corrosion resistance, and both in vitro and in vivo behavior of alloys in the ternary Mg-Ca-Sr system. Using an induction furnace with a controlled atmosphere (argon as the shielding gas), Mg-0.5Ca-xSr alloys (x = 0.5; 1; 1.5; 2; 3 at.%) were synthesized. Microstructural analyses, performed using optical microscopy and scanning electron microscopy (SEM), revealed a uniform and refined structure. Corrosion behavior assessments, carried out using linear and cyclic potentiometry, demonstrated favorable corrosion resistance for all samples. However, for the system containing 0.5% Sr, the corrosion rate values were lower compared to the other systems, and this alloy also exhibited the lowest corrosion current density. Cytocompatibility assay indicated the cytocompatible behavior of all the studied alloys, with favorable influence on cell viability and a stimulatory effect on the osteoblastic cell proliferation. In vivo biocompatibility assessments of the alloys showed that, for alloys containing 0.5% and 1% Sr, a more rapid degradation occurred in comparison with the other alloys (1.5, 2 and 3% Sr), which still persisted at the tissue level even after 12 weeks post-implantation. In all the batches examined, the inflammatory reaction was directly proportional and persistent in relation to the presence of the material in the tissue. In regions where the material was resorbed/degraded, the local inflammatory response was reduced or absent, and the fibrous tissue was denser and better organized. The field of biomaterials is in continuous development, and this study highlighted the applicability of these five alloy systems for dental and maxillofacial applications such as implants, plates, and related devices. Full article

Background. The use of zygomatic implants (ZIs) provides a highly predictable treatment option for rehabilitation in patients with severe atrophic maxillae. However, these long implants can potentially cause a number of more serious complications than those seen with conventional dental implants. The aim of this study is to report a case of peri-zygomatic cutaneous fistula following placement of monolateral double zygomatic implants and to analyse the available literature on this complication. Methods. The 55-year-old patient was treated with placement of 3 ZIs, two on the left side. Left periorbital swelling with pain appeared 10 days after surgery with progressive worsening of symptoms. After antibiotic treatment, she developed a left cutaneous fistula with purulent discharge. CT showed two ZIs on the left side with the apical portions in close contact with a 1 cm-wide portion of resorbed zygomatic external cortex and a layer of granulation tissue. Results: Due to the limited amount of bone involved by the fixation tip, the left ZIs were removed and the skin fistula repaired. The patient healed without complications but required prosthesis replacement. Conclusions. After conducting a literature review, peri-zygomatic fistulas seem to be more common in patients with two ZIs placed on the same zygoma. In this case, the amount of available zygomatic bone is relatively limited; the bone drill holes can often be too close together and cause overheating, leading to inter-implant bone resorption and infection, with further orbito-zygomatic fistula development. The authors identified the lack of distance between ZI fixtures as one of the main causes of extraoral ZI infection. Full article

Bone defects remain a significant clinical challenge, creating a severe need for advanced biomaterials for tissue regeneration. This study addresses this issue by developing 3D-printed composite hydrogels containing alginate, gelatine, and resorbable calcium phosphates (monetite and brushite) for bone tissue engineering. The scaffolds were fabricated using extrusion-based 3D printing and evaluated for their morphology, porosity, mechanical strength, swelling, degradation, and in vitro mineralization, while their cytocompatibility was assessed using LIVE/DEAD cell viability assays. The key findings demonstrate that calcium phosphate incorporation enhanced the mechanical stability by 15–25% compared to the controls, and mineral deposition increased significantly in the composite scaffolds. The developed hydrogels are bioactive and represent promising, customizable scaffolds for bone regeneration. These results support their further investigation as viable alternatives to traditional bone grafts for clinical bone tissue engineering applications. Full article

Background: This prospective clinical study aimed to evaluate the effectiveness of platelet-rich fibrin (PRF) in guided bone regeneration (GBR) prior to dental implant placement. Material and methods: Sixty-five patients with alveolar bone defects were randomly assigned to three groups. All groups received a composite graft consisting of 70% allograft and 30% xenograft. Group A received the graft combined with PRF. Group B received the graft with PRF and a resorbable collagen membrane. Group C (control) received the same graft and membrane without PRF. Cone-beam computed tomography (CBCT) was used to assess bone regeneration at baseline and 6 months postoperatively. Implant stability was evaluated using ISQ values at the time of implant placement (6 months after grafting) and again at 3 to 4 months during the second-stage uncovering procedure. Soft tissue healing, postoperative complications, and pain scores were also recorded. Results: Group B showed the best outcomes, with the highest mean vertical bone gain (3.0 ± 0.4 mm), greatest implant stability (ISQ: 74.2 ± 1.8), and no complications. Group A achieved moderate bone gain (2.3 ± 0.4 mm) and good ISQ values (71.5 ± 2.3), with favorable soft tissue healing. In contrast, Group C had the lowest bone gain (2.1 ± 0.5 mm), reduced ISQ values (68.9 ± 2.9), and the highest incidence of complications, including dehiscence and minor infections. Conclusions: These results suggest that PRF enhances both hard and soft tissue regeneration, particularly when used with grafts and membranes. PRF may reduce healing time and postoperative discomfort, improving the overall success of regenerative implant procedures. Full article

Introduction: Guided bone regeneration (GBR) is a key approach for managing alveolar ridge defects. Although titanium meshes are widely used for non-resorbable space maintenance, their limitations have prompted interest in alternative materials. Polyetheretherketone (PEEK), a high-performance thermoplastic, has emerged as a potential barrier due to its mechanical strength, radiolucency, and compatibility with digital workflows. Objective: To map the current evidence on the use of PEEK barriers in GBR, focusing on biological performance, mechanical properties, and clinical outcomes in animal and human studies. Methods: A scoping review was conducted following PRISMA-ScR guidelines. Eligible studies included in vivo animal models or clinical trials involving PEEK barriers for alveolar bone regeneration. Data on study design, defect type, barrier characteristics, surgical protocol, outcomes, and complications were extracted. Results: Five studies met the inclusion criteria: two animal models and three clinical trials. All reported successful space maintenance and bone gain with PEEK barriers, with outcomes comparable to titanium meshes. Customization through CAD/CAM or 3D printing was common. Complications such as soft tissue dehiscence and exposure occurred but generally did not affect regeneration. Evidence was limited by small sample sizes, short follow-up, and single-center designs. Conclusions: PEEK barriers show promise as customizable alternatives to traditional GBR membranes. However, current evidence is limited and geographically concentrated. Future multicenter studies with long-term follow-up and standardized outcome measures are needed to validate the clinical potential of PEEK in bone regeneration. Full article

Poly(lactic acid)/barium titanate (PLA/BT) composites exhibit piezoelectric properties desirable for bone tissue engineering, but their low biodegradability limits implant resorption. In this study, riboflavin (RF) is introduced as a dual-function additive that enhances biodegradation in PLA/BT composites. Its addition led to significantly increased microbial colonization and a five-fold higher mass loss compared to unmodified samples. These observations are consistent with the known polarity of RF and its role as a cofactor in microbial metabolism. The PLA/BT/RF composites are subjected to full characterization, including thermogravimetric analysis (TG), differential scanning calorimetry (DSC), tensile testing, dynamic mechanical analysis (DMA), dielectric permittivity measurements, and determination of piezoelectric coefficient d₃₃. Compared to PLA/BT, RF-containing composites exhibit significantly accelerated biodegradation, with mass loss reaching up to 16% after 28 days, while maintaining functional piezoelectricity (d₃₃ ≈ 3.9 pC/N). Scanning electron microscopy (SEM) performed after biodegradation reveals intensified microbial colonization and surface deterioration in the RF-modified samples. The data confirm that riboflavin serves as an effective modifier, enabling controlled biodegradation without compromising electromechanical performance. These results support the use of PLA-based piezoelectric composites for resorbable biomedical implants. Full article

The development of materials engineering allows for the creation of new materials intended for 3D printing, which has become a key tool in tissue engineering, particularly in bone tissue engineering, enabling the production of implants, defect fillers, and scaffolds tailored to the individual needs of patients. Among the wide range of available biomaterials, thermoplastic polymers such as polycaprolactone (PCL), polylactic acid (PLA), polyether ether ketone (PEEK), and polymethyl methacrylate (PMMA) are of significant interest due to their biocompatibility, processability, and variable degradation profiles. This review compiles the latest reports on the applications, advantages, limitations, and modifications in bone tissue engineering. It highlights that PCL and PLA are promising for temporary, resorbable scaffolds, while PEEK and PMMA are suitable for permanent or load-bearing implants. The inclusion of ceramic phases is frequently used to enhance bioactivity. A growing trend can be observed toward developing customized, multifunctional materials that support bone regeneration and biological integration. Despite ongoing progress, the biocompatibility and long-term safety of these materials still require further clinical validation. Full article

Background: The role of collagen membrane fixation during guided bone regeneration (GBR) remains debatable, particularly in post-extraction sockets with buccal defects and concomitant immediate implant placement. This study evaluated whether or not fixation with titanium pins improved regenerative outcomes. Methods: Six adult Beagle dogs received bilateral extractions of the fourth mandibular premolars. An implant was immediately placed in both the distal alveoli, and standardized buccal bone defects (5 mm height, 3–2 mm width) were prepared. All defects were filled with a slowly resorbing equine xenograft and covered by a resorbable pericardium membrane. At the test sites, the membrane was apically fixed with pins, while no fixation was applied to the control sites. After 3 months of healing, histomorphometric analyses were performed. Results: The vertical bone gain of the buccal crest was 3.2 mm in the test sites (pin group) and 2.9 mm in the control sites (no-pin) (p > 0.754). No significant difference was found in terms of bone-to-implant contact (BIC). However, residual graft particles were located significantly more coronally in the pin group compared to the no-pin group (p = 0.021). Morphometric analyses revealed similar new bone formation within the groups, but with higher amounts of residual xenograft and soft tissue in the pin group. Conclusions: Membrane fixation did not significantly enhance vertical bone gain, and although the slightly higher regeneration in the pin group (3.2 mm vs. 2.9 mm) may hold clinical relevance in esthetically sensitive areas and osseointegration, it appeared to limit apical migration of the grafting material. Full article

Background and Objectives: Although cyanoacrylate–polylactic acid (CA + PLA) patches shorten the time to hemostasis after partial hepatectomy, their long-term biocompatibility remains uncertain. We compared the 5-month histopathological footprint of a novel CA + PLA patch (Study group) with a licensed fibrinogen/thrombin matrix (TachoSil^® group) and electrocautery (Control group). Methods: Thirty-three male Wistar rats underwent a 3 × 1.5 cm hepatic segment resection and were randomized to the Control (n = 5), Study (n = 14), or TachoSil^® (n = 14) group. The animals were sacrificed on postoperative day (POD) 50, 100, or 150. Blinded semiquantitative scoring (0–3) was used to capture inflammation intensity, and the number of neutrophils (PMNs), lymphocytes (Ly’s), isolated histiocytes, and foreign-body giant cells (FBGCs). Results: The proportions of animals in each group across the different sacrifice time points were homogeneous (χ² = 4.34, p = 0.36). The median inflammation remained mild (2 [IQR 1–2]) in the Control and Study groups but lower in the TachoSil^® group (1 [1–2], p = 0.47). The FBGC scores differed markedly (score ≥ 2: 64% in Study, 0% in Control, 14% in TachoSil^®; p < 0.001). Fibrosis occurred almost exclusively in the Study group (79% vs. 0%; χ² = 22.4, p < 0.001). Mature vessels were most frequently observed in the TachoSil^® group (50%, aOR = 5.1 vs. Study, p = 0.04). Abscesses only developed in the Study group (29%, p = 0.046). Within the TachoSil^® group, inflammation (ρ = −0.62, p = 0.019) and Ly infiltration (ρ = −0.76, p = 0.002) declined with time; no significant temporal trends emerged in the Study group. Conclusions: At the five-month follow-up, there was an exuberant foreign-body reaction, dense collagen deposition, and a higher abscess rate around the CA + PLA patch compared with both TachoSil^® and cautery. Conversely, TachoSil^® evolved toward a mature, well-vascularized scar with waning inflammation. These findings underscore the importance of chronic-phase evaluation before clinical adoption of new hemostatic biomaterials. Full article

Senescent cells secrete pro-inflammatory cytokines, collectively referred to as the senescence-associated secretory phenotype (SASP). Certain pro-inflammatory SASP factors are known to inhibit the differentiation of bone-forming osteoblast while promoting the differentiation of bone-resorbing osteoclasts, thereby causing osteoporosis. In this study, we screened cabozantinib, a tyrosine kinase inhibitor used to treat medullary thyroid cancer, for its ability to reduce doxorubicin-induced cellular senescence in both osteoblast and osteoclast progenitors. This non-cytotoxic agent suppressed the secretion of SASP factors (e.g., TNFα, IL1α, IL1β, IL6, and CCL2) from senescent osteoblast and osteoclast progenitors, resulting in enhanced osteoblast differentiation and reduced osteoclast differentiation. Furthermore, intraperitoneal administration of cabozantinib to age-related estrogen-deficient mice subjected to ovariectomy prevented bone loss without apparent side effects, increasing osteoblast numbers and reducing osteoclast numbers along the surface of the trabecular bone. In summary, our findings suggest that anti-aging cabozantinib has potential as a preventive anti-osteoporotic agent by promoting osteogenesis and inhibiting osteoclastogenesis through the repression of SASP. Full article