Background: Zirconia ceramics are generally used in monolithic restorations, and their microstructural, mechanical, and optical properties continue to improve. Several factors affect the mechanical properties of these restorations; however, the combined effects of yttria content and margin design on the fracture resistance remain unclear. Methods: Sixty monolithic zirconia crowns were fabricated and assigned to six groups (n = 10) based on three different yttria contents (strength-gradient multilayer zirconia containing 3 mol% yttria tetragonal zirconia polycrystals in the dentin region and 5 mol% yttria-partially stabilized zirconia in the occlusal region: 3Y-TZP/5Y-PSZ [ZP], 3 mol% yttria tetragonal zirconia polycrystals: 3Y-TZP [HTML], and 4 mol% yttria-partially stabilized zirconia: 4Y-PSZ [STML]), and two different margin designs (chamfer and rounded shoulder). Crowns were adhesively bonded to standardized 3-dimensional-printed resin dies and subjected to thermal and mechanical aging (10,000 thermocycles at 5–55 °C, and 1.2 million mechanical cycles at 50 N, 1.6 Hz). Fracture resistance values were recorded in Newtons, and fracture types were evaluated. Data were analyzed using a two-way analysis of variance (ANOVA), and Bonferroni adjustment was used for multiple comparisons (α = 0.05). Results: A significant interaction between yttria content and margin design was found (p = 0.005). In the chamfer margin design groups, ZP (2208.5 ± 501.9 N) and HTML (2069.6 ± 463.3 N) showed significantly higher fracture resistance than STML (1444 ± 303.2 N) (p < 0.05). In the rounded shoulder margin design groups, no significant differences were observed among ZP (1662.8 ± 293.8 N), HTML (1940.9 ± 341.6 N), and STML (1795.6 ± 529.6 N) (p > 0.05). ZP and HTML showed higher fracture resistance values with the chamfer margin design, while STML showed higher fracture resistance with the rounded shoulder margin design. Conclusions: The fracture resistance of zirconia restorations is influenced by both the margin design and the yttria content. Designing the margin geometry based on the type of zirconia to be used can enhance the mechanical properties of the restorations and support clinical decision-making.

The design of implant surfaces that support bone integration while limiting bacterial colonization remains a central challenge in biomaterials science and engineering. In this work, zinc-doped biomimetic calcium phosphate (CaP-Zn) coatings were fabricated on Ti6Al4V through surface activation followed by deposition in supersaturated simulated body fluid (SBF). Acid and alkali–calcium treatments produced a porous, calcium-rich interface that enabled the uniform formation of apatite-like CaP layers. Zinc incorporation was achieved without suppressing the formation of CaP phases and led to systematic changes in coating microstructure and surface chemistry. Spectroscopic and structural analyses indicated Zn incorporation within the CaP matrix, consistent with partial Ca2+ substitution and its association with poorly crystalline domains. These features promoted controlled ionic release and localized dissolution–reprecipitation behavior. Antibacterial testing against Streptococcus mutans revealed a clear Zn-dependent reduction in bacterial viability, while cytocompatibility remained within acceptable limits at moderate Zn levels. Finally, the coatings combine intrinsic bioactivity with ion-mediated antibacterial functionality, offering a multifunctional surface strategy for advanced titanium-based implants.

The reconstruction of complex orbitomaxillary defects requires biomaterials that can simultaneously provide structural stability, biocompatibility, and accurate restoration of facial volume and contour. While rigid polymers such as polyetheretherketone (PEEK) offer reliable mechanical support, they do not adequately replicate the viscoelastic behavior of soft tissues. This report presents a translational revision case employing a personalized hybrid biomaterial approach that combines a 3D-printed PEEK implant for structural orbital floor support with a patient-specific polydimethylsiloxane (PDMS) implant for malar volumetric augmentation. Reconstruction was planned using CT segmentation and contralateral mirroring. Patient-specific implants were subsequently designed using CAD/CAM techniques, combining a rigid PEEK implant for structural orbital support with a flexible PDMS implant for malar volumetric augmentation with complementary mechanical properties. Revision surgery included the removal of inadequately positioned titanium hardware, the release of incarcerated extraocular muscles, and the restoration of orbital anatomy and facial symmetry. Postoperative imaging demonstrated stable implant positioning and sustained orbitomaxillary stability. Despite successful anatomical reconstruction, residual functional sequelae, including strabismus related to the severity of the initial orbital trauma, persisted and were addressed separately in a staged manner, resulting in satisfactory ocular alignment and resolution of diplopia in primary gaze. This case underscores the complementary functional roles of rigid and elastic polymers and highlights the translational potential of PDMS as a permanent, patient-specific implant material for volumetric and contour restoration in craniofacial reconstruction.

Background/Objectives: The subciliary approach offers excellent exposure for orbital and zygomaticomaxillary complex fracture repair but is associated with a relatively high risk of postoperative lower eyelid ectropion. This study evaluated the preventive efficacy of an acellular dermal matrix (ADM; WITHderm®) spacer graft placed during subciliary incision repair. Methods: This prospective observational cohort study included 20 patients who underwent open reduction and internal fixation for orbital wall or zygomaticomaxillary complex fractures using a subciliary approach between June and December 2024. A human-derived ADM (WITHderm®) spacer graft was interposed between the orbital septum and the orbicularis oculi muscle during incision closure. Postoperative outcomes were assessed at three time points: ectropion grading at 1 month and scar outcomes at 3 and 6 months using the Patient and Observer Scar Assessment Scale (POSAS). Results: No patients developed postoperative lower eyelid ectropion at 1-month follow-up (0% incidence). Both patient-reported and observer-reported scar outcomes improved significantly over time. The mean total PSAS score decreased from 21.0 ± 2.85 at 3 months to 11.3 ± 2.13 at 6 months (p < 0.001), while the mean total OSAS score decreased from 21.35 ± 2.25 to 11.4 ± 1.67 (p < 0.001). Overall patient satisfaction and objective scar ratings also showed significant improvement. Conclusions: ADM (WITHderm®) spacer grafting during subciliary incision repair appears to be a safe and effective strategy for preventing early postoperative lower eyelid ectropion and achieving favorable scar outcomes. Further studies are warranted to confirm these findings.

The accuracy of static computer-aided implant surgery (s-CAIS) is fundamental for predictable clinical outcomes. The objective of this study was to evaluate the influence of different guide-support modalities on the linear and angular accuracy of implant placement. In this retrospective clinical investigation conducted at a single specialty hospital, a total of 180 implants were analyzed, divided into three equal groups (n = 60) based on the guide support type: tooth-supported, bone-supported, and mucosa-supported. Accuracy was assessed by superimposing preoperative virtual plans with postoperative cone-beam computed tomography (CBCT) scans, measuring linear deviations at the neck and apex of the implant, as well as angular discrepancies. The type of guide support was found to be a significant factor associated with surgical accuracy (p < 0.001). Tooth-supported guides demonstrated the highest level of accuracy, with a mean angular deviation of 1.81° ± 0.45° and linear deviations at the neck and apex of 0.59 ± 0.18 mm and 0.73 ± 0.19 mm, respectively. These were followed by bone-supported guides (2.14° ± 0.48°; 1.04 ± 0.26 mm; 1.61 ± 0.31 mm), while mucosa-supported guides exhibited the greatest deviations (2.95° ± 0.60°; 1.47 ± 0.29 mm; 1.87 ± 0.37 mm). Significant intergroup differences and large effect sizes were observed, particularly regarding angular and horizontal discrepancies. These findings demonstrate a distinct gradient of accuracy based on guide support, establishing tooth-supported guides as the most accurate, followed by bone-supported and, lastly, mucosa-supported guides. While all modalities are clinically applicable, the use of mucosa-supported guides necessitates increased safety margins to account for the increased risk of linear and angular discrepancies inherent to mucosal tissue displacement.

Although immunotherapy has shown great promise in treating various types of cancer, advanced tumors are often refractory due to a highly immunosuppressive tumor microenvironment (TME). We previously engineered a cancer therapeutic vaccine platform, µGCVax, by co-loading tumor antigen peptides, STING and TLR9 agonists into porous silicon microparticles. While effective in models with lower disease burden, its efficacy against advanced colorectal cancer (CRC) was less promising due to the accumulation of myeloid-derived suppressor cells (MDSCs) in TMEs. In this study, we investigated whether µGCVax-based immunotherapy in advanced CRCs could be potentiated via regulating MDSCs to reprogram the TME. In an advanced CT26 murine CRC model, we assessed µGCVax in combination with oxaliplatin, a standard CRC chemotherapeutic with established immunomodulatory effects. We demonstrated that oxaliplatin was preferentially taken up by monocytic MDSCs (M-MDSCs) and effectively reduced their abundance in the bone marrow, blood, spleen, and tumor. Relief of this immunosuppressive TME increased intratumoral infiltration of antigen-specific CD8+ T cells. Ultimately, the combination of oxaliplatin with µGCVax induced robust regression of established CRC tumors. These findings highlight that oxaliplatin synergizes with µGCVax by overcoming MDSC-mediated immunosuppression and enhancing antitumor immunity, representing a promising chemo-immunotherapy strategy for advanced CRC.

Adequate alveolar bone volume is a prerequisite for predictable and long-term success in dental implant therapy. Physiological post-extraction remodeling frequently results in horizontal and vertical ridge deficiencies, which may compromise optimal implant placement. Guided bone regeneration (GBR) has become a cornerstone procedure in implant dentistry, with clinical outcomes largely influenced by the biological and mechanical characteristics of grafting materials. Different bone grafts and their combinations are currently clinically applicable, each exhibiting distinct osteogenic, osteoinductive, and osteoconductive properties, as well as varying resorption profiles and volumetric stability. This narrative review aims to analyze the biological principles of alveolar ridge augmentation, compare the properties of commonly used graft materials, evaluate clinical outcomes, and discuss emerging regenerative strategies. Literature published between 2000 and 2025 was assessed to synthesize current evidence regarding graft integration, bone formation, desorption dynamics, and clinical indications. Autogenous bone remains the gold standard due to its combined osteogenic, osteoinductive, and osteoconductive potential; however, its limitations have driven the development of alternative materials, including allografts, xenografts, alloplastic substitutes, demineralized tooth matrices, platelet concentrates, and customized scaffolds. While no single material is universally ideal, appropriate selection based on defect characteristics and clinical objectives is essential for predictable outcomes. Future research should prioritize long-term comparative trials, biomaterial standardization, and biologically enhanced regenerative approaches.

In computer-aided design/computer-aided manufacturing (CAD/CAM) restorations for severely damaged teeth, the cavity floor or proximal margins may be elevated with composite resin to improve adhesion. This in vitro study investigated how different surface pretreatment methods affect the shear bond strength (SBS) of hybrid CAD/CAM materials to dentin or composite surfaces, simulating clinical situations of composite elevation. Hybrid CAD/CAM samples were bonded to dentin or composite substrates following different surface pretreatment protocols and cemented using a dual-cure adhesive resin cement. The samples were thermocycled and subjected to shear bond strength testing, and failure modes were analyzed. The SBS in the sandblasting (SB)+Dentin group and hydrofluoric acid (HF)+Dentin was significantly higher than that in the SB+Composite and HF+Composite groups (p < 0.05). Untreated+composite and untreated+dentin groups showed significantly lower SBS (p < 0.05). Failure mode analysis revealed a predominance of cohesive failures in the SB+Dentin group, while adhesive failures were more frequently observed in most of the other groups. SB-treated and HF-etched hybrid CAD/CAM materials showed more favorable bonding behavior to dentin than to composite, highlighting that bonding to the elevated composite layer may be less effective than bonding directly to prepared dentin.

Mesoporous bioactive glass (MBG) has been extensively studied in bone regeneration due to its excellent bioactivity and osteoconductive properties. Here, we prepared amino-modified MBG (MBG-NH2) adsorbed osteopontin (OPN) to form MBG-NH2/OPN composites, enabling the sustained release of OPN and enhancing osteoblast differentiation and mineralization capacity. Interestingly, we observed that MBG-NH2 promotes the formation of osteoid deposits and calcium deposition in vitro. Furthermore, we also found that MBG-NH2/OPN significantly enhances cell adhesion, differentiation, and mineralization. Consistent with these observations, we found the expression of the osteoblast-specific marker gene increased, including bone morphogenetic protein 2 (Bmp2) and Collagen I. Intriguingly, we also found that MBG-NH2/OPN promotes osteoblast differentiation and mineralization through activating the extracellular regulated protein kinases1/2 (Erk1/2) signaling pathway. We concluded that MBG-NH2/OPN enhances osteoblast differentiation and mineralization through the Erk1/2 pathway. These findings indicate that MBG-NH2/OPN is a new potential biomaterial for bone regeneration.

The orthodontic landscape is currently witnessing a significant technological evolution with the emergence of direct 3D-printed aligners (DPAs), which promise to close the digital workflow loop by eliminating the geometric limitations and solid model waste inherent to traditional thermoformed clear aligners (TCAs). This review provides a comprehensive analysis of the material science governing this transition from inert thermoplastic sheets to reactive photocurable resins. We explore the fundamental chemistry of DPA materials, and the pivotal role of post-processing in ensuring mechanical integrity and biocompatibility. Beyond passive mechanics, this review highlights preclinical research in functional material engineering, detailing how experimental DPAs are being investigated for the integration of antibacterial agents, remineralization fillers, and drug delivery systems. Furthermore, we evaluate the limited but emerging clinical data on DPAs, contrasting their shape-memory properties and force delivery profiles with conventional appliances, while critically addressing emerging safety concerns regarding monomer elution and microplastic generation. We conclude that while DPA technology offers superior dimensional control, comprehensive life cycle assessments and long-term in vivo trials are essential to fully substantiate their clinical efficacy, overall sustainability, and potential as advanced orthodontic appliances.