PURPOSE:To evaluate the in vivo efficacy of bone morphogenetic protein 9 (BMP9) relative to bone morphogenetic protein 2 (BMP2) in a beagle peri-implant critical-size defect model. METHODS:Peri-implant defects were created in beagle dogs and treated with either a collagen sponge (CS) or deproteinized bovine bone mineral with collagen (OCS-B Xenomatrix collagen [OCS-BC]), with or without BMP2 or BMP9. After 8 weeks, bone regeneration and osseointegration were evaluated using radiographic, histological, and biomechanical analyses. RESULTS:Radiographic analysis demonstrated that BMP treatment significantly increased peri-implant mineralization, with bone mineral density increasing from 0.597±0.151 (control) to 0.896±0.173 in the CS+BMP9 group (P<0.0001). Histological and histomorphometric analyses corroborated these findings, showing greater new bone formation and higher bone-to-implant contact (BIC) (7.943±7.048 vs. 68.90±20.27 in the CS+BMP9 group; P<0.05) without overt inflammatory reactions. Region-of-interest (ROI)-based micro-computed tomography analysis (200 μm) and resonance frequency analysis further supported improved osseointegration and stability, with osseointegration increasing from 20.32±6.976 to 70.37±0.785 in the CS+BMP9 group (P<0.0001) and the implant stability quotient (ISQ) peaking at 70.92±3.523 in the OCS-BC+BMP9 group (P<0.0001). Two-way analysis of variance indicated scaffold-dependent magnitudes for bulk endpoints, whereas interaction terms were not significant for BIC, ROI-based osseointegration, or ISQ, supporting preservation of BMP9-associated benefits across scaffold types for these outcomes. CONCLUSIONS:BMP9 produced overall improvements comparable to BMP2 and may provide more reproducible osseointegration-related outcomes across scaffold types.

Early osseointegration is a critical determinant of implant success. In this study, we systematically compared the surface characteristics and the osteoimmunological cascade of early healing—macrophage polarization, vascular endothelial growth factor (VEGF) expression, osteoconduction, histomorphometric osseointegration, and biomechanical stability—of commercially available modified sandblasted, large-grit, acid-etched-surface (modified SLA-surface; SLActive®, Straumann AG, Switzerland) and apatite-surface (Osstem TSIII BA, Osstem, Republic of Korea) implants. Surface morphology/roughness of apatite and modified-SLA implants were assessed by Field emission scanning electron microscopy (FE-SEM) and profilometry. Immunoangiogenic responses were evaluated in a rat calvarial defect model using immunofluorescence for CD11c, CD163, and vascular endothelial growth factor (VEGF). Early osseointegration was tested in rat femoral condyles (bone area, bone-to-implant contact (BIC)) and canine mandibles (BIC, removal torque) at set intervals. FE-SEM showed a distinct micro- or nanoscale topography. Profilometry confirmed the presence of comparable microroughness (2.143 vs. 2.223 μm). In rat calvarial defects, the apatite-surface showed a higher CD163 (M2) signal and M2/M1 ratio than the modified SLA-surface on days 4 and 7 (P<0.05), and a higher VEGF signal on days 4 and 6 (P<0.05). In rat femur condyles, bone area was comparable; however, on day 7, BIC was significantly higher on the apatite-surface than on the modified SLA-surface (P<0.05). In canine mandibles, removal torque was significantly higher on the apatite-surface at both 3 and 6 weeks (P<0.05), and BIC was also significantly higher at 3 and 6 weeks (P<0.05). Within the limits of the present preclinical models, the apatite-surface was associated with a shift toward M2-polarized macrophages, increased VEGF expression, and improved early osseointegration compared with the modified SLA-surface.

Soft-tissue substitutes are increasingly used to avoid donor-site morbidity associated with autogenous grafting, yet direct preclinical comparisons of acellular allogenic dermal matrix (ADM) and collagen matrix (CM) remain scarce. This study investigated the early healing and remodeling profiles of ADM and CM in a canine split-mouth model. Eight male mongrel dogs (16 labial sites at the maxillary second incisors) received randomized subperiosteal tunnel grafting with ADM or CM and were euthanized at 4 or 8 weeks (n = 4 per time point). Gingival thickness and volume were quantified by 3D intraoral scans. At sacrifice, histometric thickness, rete peg counts, hematoxylin and eosin interface morphology, and immunohistochemical expression of type I collagen (Col I) and vascular endothelial growth factor (VEGF) were evaluated. Both materials produced immediate soft-tissue gains followed by partial contraction during healing while remaining above baseline. At 4 and 8 weeks, no detectable between-material differences were observed in histometric and 3D outcomes, rete peg counts, or VEGF expression. Histology showed close graft-host apposition at 4 weeks and a denser, collagen-rich interface at 8 weeks. Col I expression increased in both groups. These findings suggest similar early healing and connective tissue remodeling patterns within the limitations of this short-term canine model.

Implant surface modification techniques have shifted from simple mechanical modifications to sophisticated strategies aimed at modulating biological responses at the bone-implant interface. This study aimed to compare sandblasted, large-grit, acid-etched (SLA) and apatite-coated dental implant surfaces, focusing on their biological, immunological, and mechanical performance. Surface morphology and wettability were assessed by field emission scanning electron microscopy and liquid spreading tests, respectively. In vitro assays evaluated osteoblast adhesion, alkaline phosphatase (ALP) staining, and mineralization. In vivo performance was examined using rat femoral condyle loosening and calvarial defect models to assess early bone formation, macrophage polarization, and vascular endothelial growth factor (VEGF) expression. A beagle mandibular tooth extraction model was used to measure removal torque (RT) and bone-to-implant contact (BIC). The apatite-coated surface exhibited a uniform nanostructured apatite layer with superior wettability compared to the SLA surface. In vitro, apatite-coated surface significantly enhanced osteoblast adhesion and mineralization (p < 0.05). In vivo, apatite-coated surface promoted peri-implant bone formation, accelerated the shift from M1 to M2 macrophages, and increased VEGF expression. In the beagle model, apatite-coated implants demonstrated higher RT and BIC at all time points. Apatite-coated on dental implants enhances osseointegration through combined biological, mechanical, and immunomodulatory effects, promoting rapid bone healing and stable implant fixation.

AIM:To compare clinical and radiographic outcomes of titanium and zirconia implants placed supracrestally into fresh extraction sockets in a canine model with naturally occurring periodontitis. MATERIALS AND METHODS:A total of 32 implants were placed in eight dogs. The titanium (Control, Group 1) and zirconia (Test, Group 2) implants with a 0.4 mm machined collar were placed into fresh extraction sockets at two vertical positions: 0 mm (subgroup a) and 1 mm (subgroup b) exposure of rough surface to make the artificial condition of alveolar bone loss around the implant. Peri-implant mucosal tissue inflammation (MTI), implant stability quotient (ISQ), and marginal bone loss (MBL) were evaluated at 6, 12, and 18 weeks postoperatively. RESULTS:Zirconia implants demonstrated comparable results to titanium in implant stability and peri-implant soft tissue response. Although MTI scores were slightly higher in zirconia implants than titanium for the entire period, there was no significant issue during osseointegration. The ISQ values increased significantly at 6 weeks in all groups. Mean MBL gradually increased over time; among implants with exposed rough surfaces, Group 1b exhibited the highest MBL (0.71 ± 0.38 mm), whereas Group 2b showed significantly less bone loss (0.32 ± 0.30 mm) (p = 0.05). CONCLUSIONS:In natural periodontitis canine model, titanium and zirconia implants placed into fresh extraction sockets demonstrated similar stability during healing period. Zirconia implants exhibited significantly less MBL than titanium under the condition of rough surface exposure, indicating a more favorable peri-implant bone response with zirconia.

Early osseointegration is a critical determinant of implant success. In this study, we systematically compared the surface characteristics and the osteoimmunological cascade of early healing—macrophage polarization, vascular endothelial growth factor (VEGF) expression, osteoconduction, histomorphometric osseointegration, and biomechanical stability—of commercially available modified sandblasted, large-grit, acid-etched-surface (modified SLA-surface; SLActive®, Straumann AG, Switzerland) and apatite-surface (Osstem TSIII BA, Osstem, Republic of Korea) implants. Surface morphology/roughness of apatite and modified-SLA implants were assessed by Field emission scanning electron microscopy (FE-SEM) and profilometry. Immunoangiogenic responses were evaluated in a rat calvarial defect model using immunofluorescence for CD11c, CD163, and vascular endothelial growth factor (VEGF). Early osseointegration was tested in rat femoral condyles (bone area, bone-to-implant contact (BIC)) and canine mandibles (BIC, removal torque) at set intervals. FE-SEM showed a distinct micro- or nanoscale topography. Profilometry confirmed the presence of comparable microroughness (2.143 vs . 2.223 µm). In rat calvarial defects, the apatite-surface showed a higher CD163 (M2) signal and M2/M1 ratio than the modified SLA-surface on days 4 and 7 ( P < 0.05), and a higher VEGF signal on days 4 and 6 ( P < 0.05). In rat femur condyles, bone area was comparable; however, on day 7, BIC was significantly higher on the apatite-surface than on the modified SLA-surface ( P < 0.05). In canine mandibles, both removal torque and BIC were higher on the apatite-surface than on the modified SLA-surface at 3 and 6 weeks ( P < 0.05). Within the limits of the present preclinical models, the apatite-surface was associated with a shift toward M2-polarized macrophages, increased VEGF expression, and improved early osseointegration compared with the modified SLA-surface.

OBJECTIVES:This study compared the osteogenic mechanisms and preclinical efficacy of bone morphogenetic protein 9 (BMP9) and BMP2 in vitro and in a beagle peri-implant defect model in vivo. MATERIALS AND METHODS:In vitro, MC3T3-E1 preosteoblasts were treated with BMP2 or BMP9 to assess osteogenic gene expression (Col1, Runx2, Alp, Ocn) by real-time PCR, Smad1/5/9 phosphorylation by western blotting, and osteogenesis by alkaline phosphatase (ALP) and Alizarin Red S staining. In vivo, saddle-type peri-implant defects were created in beagle mandibles and treated with a collagenated xenograft matrix with or without BMP2 or BMP9 (150 μg/site). After 8 weeks, implant stability, micro-CT, histomorphometry, and osseointegration parameters were analyzed. RESULTS:BMP9 significantly enhanced osteogenic gene expression, Smad1/5/9 phosphorylation, ALP activity, and mineralization compared to BMP2. In vivo, BMP9 yielded the highest implant stability values, greater defect fill, and higher bone volume fraction, bone mineral density, and bone-to-implant contact. CONCLUSIONS:BMP9 showed stronger osteoinductive potential than BMP2, resulting in improved bone regeneration and osseointegration. These findings suggest that BMP9 is a promising growth factor for improving dental implant outcomes.

Lateral sinus augmentation is a widely used procedure for implant placement in the posterior maxilla with insufficient residual bone height. This study retrospectively described the clinical and radiographic outcomes of lateral sinus augmentation performed using a controlled osteotomy strategy, referred to as the Wedge and Feather (WF) technique, and explored factors potentially associated with vertical bone gain. This descriptive retrospective case series included consecutive patients who underwent lateral sinus augmentation using the WF technique. Clinical and radiographic data were collected from routine records. Vertical bone gain and complication rates were summarized descriptively. Because of the small sample size and absence of a control group, inferential analyses were considered exploratory and hypothesis-generating. A total of 38 patients (43 sinus augmentation sites, 55 implants) was included. The mean vertical bone gain measured on postoperative panoramic radiographs was 8.5 ± 2.3 mm (range: 3.8–13.3 mm). Schneiderian membrane perforation occurred in 2 sites (4.7

Periodontal tissue regeneration requires coordinated cellular responses among multiple cell types, supporting matrix components, and signaling proteins, including bone morphogenetic proteins (BMPs). Despite extensive studies on BMP2, the regenerative role of BMP9 and its interplay with BMP2 in shaping bone and cementum repair remain poorly understood. Notably, BMP9 was independent of the antagonist Noggin, and molecular dynamics simulations confirmed that the Noggin-BMP9 complex exhibited greater root mean square deviation (RMSD) values and unstable interactions in periodontal ligament stem cells (PDLSCs). Functionally, BMP9 notably enhanced the osteogenic and cementoblastic differentiation of PDLSCs, elicited minimal osteoclast activation, and improved the survival of PDLSCs and macrophages by attenuating stress-induced apoptosis and preserving mitochondrial membrane potential. BMP9 also induced epithelial-mesenchymal transition (EMT) and exhibited synergy with endogenous matrix proteins to enhance mineralization. To optimize BMP localization in the application site, sponge type collagen scaffolds were attempted. Type I collagen sponges crosslinked with carbodiimide (EDC/NHS) and dehydrothermal (DHT) were compared, and the DHT-crosslinked sponge was selected for its larger pores, higher absorbency, and higher BMP9 loading efficiency. In a canine periodontal defect model, BMP9-loaded DHT-collagen sponges facilitated integrated regeneration of cementum, periodontal ligament, and alveolar bone, accompanied by localized ApoBD-like structures associated with PDLSC- and macrophage-related markers. Transcriptomic profiling revealed notable induction of gene sets related to EMT and cementogenesis, underscoring the role of BMP9 in driving periodontal tissue homeostasis. Collectively, these findings establish high-affinity BMP9 delivery via a collagen sponge as an effective and clinically translatable strategy for periodontal tissue regeneration.

PURPOSE:This systematic review and meta-analysis quantitatively synthesized the available evidence on the association between periodontal disease (PD) and the risk of medication-related osteonecrosis of the jaw (MRONJ). We also examined whether MRONJ risk varied according to PD severity among patients receiving antiresorptive or antiangiogenic therapy. METHODS:MEDLINE, Web of Science, Embase, Scopus, and Google Scholar were comprehensively searched for studies published through November 30, 2025, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eligible studies were required to provide a reproducible definition of PD based on clinical, radiographic, guideline-based, or predefined administrative-code criteria. Studies relying on non-operationalized clinical labels without sufficient diagnostic detail were excluded. A random-effects meta-analysis was performed using log-transformed relative-effect estimates and their standard errors. To address heterogeneity in exposure definitions, studies were stratified into a severe/procedure-linked group and a moderate-to-mixed group. RESULTS:Eight observational studies met the eligibility criteria and were included in the quantitative synthesis. The primary meta-analysis showed a statistically significant association between PD and MRONJ, indicating that patients with PD had an approximately threefold higher risk of developing MRONJ than those without PD (pooled relative-effect estimate, 3.02; 95% confidence interval [CI], 1.99-4.56). In subgroup analyses, the severe/procedure-linked group had a higher pooled relative-effect estimate (4.26; 95% CI, 1.96-9.24) than the moderate-to-mixed group (2.39; 95% CI, 1.45-3.94). However, the between-subgroup difference was not statistically significant; therefore, the subgroup findings should be interpreted as exploratory. CONCLUSIONS:Current evidence supports an association between PD and increased MRONJ risk in patients receiving antiresorptive or antiangiogenic therapy. Although the subgroup findings suggest that more advanced periodontal breakdown may be associated with greater risk, this severity-based pattern should be interpreted cautiously and confirmed in future studies with larger sample sizes and standardized diagnostic criteria.

Objectives: This study sought to evaluate the efficacy of cancellous bovine bone mineral granules and 10% porcine collagen (deproteinized bovine bone mineral with collagen [DBBM-C]; (OCS-B Collagen (R) [Straumann XenoFlex], NIBEC, Korea) in a mouldable block form, with or without socket seal, using autogenous free gingival graft (FGG). Methods: Fifty-four patients were included and randomly assigned to one of three groups: (1) spontaneous healing (control group), (2) alveolar ridge preservation (ARP) using DBBM-C (DBBM-C group), and (3) ARP employing DBBM-C sealed with FGG (DBBM-C/FGG group). Bone biopsy and implant fixture placement were performed 180 days after ARP. Conebeam computed tomography, histological analysis, implant stability, and three-dimensional volumetric analysis were conducted. Results: Of the 54 patients, 4 dropped out owing to loss of follow-up and osseointegration failure. The changes in alveolar bone during follow-up were not significantly different. Between 84- and 180-day postextraction, the volume of the DBBM-C and DBBM-C/FGG groups was maintained at 3 mm below the alveolar ridge crest (0.72 f 0.80 mm, 6.05 f 6.69%), whereas the volume in the control group decreased (-0.37 f 1.31 mm, -2.10% f 8.37%) (P = .026). The DBBM-C/FGG group exhibited less horizontal ridge resorption at 1 mm below the alveolar crest (-9.19 f 5.09 mm, -73.67% f 32.53%) between preextraction and 84 days postextraction (P = .049). In all groups, the implant stability quotient remained above 70. Conclusions: Within the limitations of this study, both ARP using DBBM-C with and without socket sealing effectively preserved the width dimension of the alveolar ridge, with no significant difference in alveolar bone resorption. However, socket sealing appeared to enhance the stability of the bone graft and bone quality. Clinical Relevance: The use of DBBM-C for ARP seems to aid in volume maintenance as compared with spontaneous healing. Gingival sealing with an FGG can help maintain the width of the alveolar ridge. This clinical trial was not registered prior to participant recruitment and randomization. This study was registered at WHO ICTRP (https://trialsearch.who.int/ (c) 2024 The Authors. Published by Elsevier Inc. on behalf of FDI World Dental Federation. (http://creativecommons.org/licenses/by-nc-nd/4.0/)

With the increasing demand for comprehensive smile esthetics, pink esthetics—referring to the harmonious appearance of the gingival tissues—has gained significant attention. However, conditions such as gingival recession, black triangles, and gummy smiles can compromise these outcomes and remain challenging to manage with conventional surgical approaches. This study aimed to review minimally invasive and simplified approaches for pink esthetic enhancement using biomaterials such as collagen matrix, hyaluronic acid dermal fillers, and botulinum toxin. The use of a collagen matrix for gingival phenotype modification has demonstrated effectiveness in achieving root coverage and increasing gingival thickness while offering a less invasive alternative to traditional surgical techniques. Interdental papilla loss—commonly referred to as the “black triangle”—remains difficult to correct using both surgical and restorative procedures; however, hyaluronic acid dermal fillers offer a promising solution for reconstructing interdental gingival architecture. Additionally, excessive gingival display (gummy smile) caused by hyperactivity of the upper lip elevator muscles can be efficiently managed with botulinum toxin injections, providing a nonsurgical option for improving smile esthetics. The use of these biomaterials in pink esthetic management enables clinicians to achieve favorable esthetic outcomes with reduced invasiveness. This approach minimizes the need for additional restorative or surgical interventions, thereby enhancing patient comfort and satisfaction.

This study aimed to evaluate the osteogenic capacity of two types of collagenated xenogenic bone grafts (OCS-B Collagen®, NIBEC, Jincheon, Korea and Bio-Oss® Collagen, Geistlich, Wolhusen, Switzerland) in artificial bone defects in beagle dogs. The bilateral mandibular premolars of 13 male beagles were extracted, followed by the creation of standardized bony defects after 4 weeks. The defects were grafted with or without the two bone grafts and covered by a collagen membrane. Dental implants were placed 24 weeks post grafting. Bone regeneration and osseointegration were evaluated using micro-computed tomography (micro-CT), as well as histological and histomorphometric analyses, while implant stability was measured using resonance frequency analysis (RFA). Micro-CT revealed that both grafts significantly increased bone mineral density (BMD), bone volume (BV), total volume (TV), and BV/TV at 8 and 16 weeks. Twenty-four weeks after implant placement, comparable BMD, BV/TV, and bone-to-implant contact values indicated effective osseointegration. Histological analysis revealed new bone formation and integration between grafts. Histomorphometric analysis demonstrated the preservation of bone height and angle. RFA indicated good implant stability in both groups. The two collagenated xenogenic bone grafts exhibited similar osteogenic potential and osseointegration in an artificial bone defect and implant model. Clinically, both grafting materials may provide comparable outcomes in bone regeneration and implant stability.

BACKGROUND:Collagenated bovine bone mineral (CBBM) is used for maxillary sinus elevation-based augmentation. We compared collagen degradation in cross-linked (CL) CBBM and non-cross-linked (NCL) CBBM (in vitro) and preclinical results in CBBM-CL, CBBM-NCL, deproteinized bovine bone mineral (DBBM), and DBBM with fibrin sealant grafts (in vivo) after repair of perforated Schneiderian membrane (SM). METHODS:Collagenase-based degradation rates of CBBM-CL and CBBM-NCL were compared in vitro and in vivo (CBBM-CL, CBBM-NCL, DBBM, and DBBM with fibrin glue; n = 12 defects per group). After bilateral maxillary SM perforation (5 mm) during sinus elevation, we performed bone substitute-based augmentation. At 4 and 12 weeks postoperatively, volumetric, histologic, and histomorphometric analyses were performed. RESULTS:Complete degradation and 33% retention of collagen content after 24 and 72 h were noted in CBBM-NCL and CBBM-CL, respectively. CBBM-NCL demonstrated significant differences in total augmentation volume (TAV) compared to DBBM and DBBM with fibrin glue, as well as in new bone volume (NBV) compared to DBBM with fibrin glue. At 12 weeks, significant differences were observed between CBBM-NCL and DBBM in NBV. There were no significant differences across all groups in vertical bone increase in 4 and 12 weeks. DBBM and DBBM with fibrin glue showed more irregularly shaped patterns than CBBM-CL and CBBM-NCL. At 12 weeks, ossification progressed in all groups. At 4 weeks, DBBM with fibrin glue seemed to demonstrate early ossification at the perforation site in histological observations compared to DBBM alone; however, no differences were observed at 12 weeks. CONCLUSION:CBBM for perforated SM repair confers bone stability and ossification. CBBM-CL was noninferior to CBBM-NCL in volume stability. The findings indicate that the CL collagen in CBBM-CL contributes to enhanced graft stability over time. Fibrin glue appeared to have a positive effect on early ossification in histological evaluations, but this effect was not evident at 12 weeks. PLAIN LANGUAGE SUMMARY:Collagenated bovine bone mineral (CBBM) is used for maxillary sinus elevation-based augmentation. We compared collagen degradation in cross-linked (CL) CBBM and non-cross-linked (NCL) CBBM (in vitro) and preclinical results in CBBM-CL, CBBM-NCL, deproteinized bovine bone mineral (DBBM), and DBBM with fibrin sealant (in vivo) after repair of perforated Schneiderian membrane (SM). After bilateral maxillary SM perforation (5 mm) during sinus elevation, we performed bone substitute-based augmentation. At 4 and 12 weeks postoperatively, volumetric, histologic, as well as histomorphometric analyses were performed. Based on this study, CL collagen in CBBM-CL contributes to enhanced graft stability over time. Fibrin glue appeared to have a positive effect on early ossification in histological evaluations, but this effect was not evident at 12 weeks.

This retrospective study aimed to evaluate the up to 10-year survival rate of tapered internal dental implants featuring an 11° Morse taper and internal hex connection with sandblasted and acid-etched (SA) surfaces and to determine whether patient-related or procedural variables significantly influence implant longevity. A total of 2474 tapered internal implants featuring an 11° Morse taper and internal hex connection with SA surfaces (Osstem TS III SA) were placed in 1298 patients at Seoul National University Dental Hospital in Korea between 2013 and 2019. Inclusion criteria required at least 5 years of follow-up postprosthesis placement. Variables such as sex, age, diabetes mellitus, smoking status, implant location, diameter, length, surgical protocol, timing, bone augmentation, and prosthesis type were analyzed. Kaplan-Meier survival analysis and Cox proportional hazards modeling were performed using SPSS 29.0. The overall implant survival rate was 98.3%. Peri-implantitis was the leading cause of failure. Cox analysis showed that only sex significantly affected implant survival, with male patients exhibiting a higher risk of failure (HR, 0.347; P = .004). No other clinical or procedural variables, including diabetes, smoking, or implant dimensions, showed statistically significant effects. Within the limitations of this single-center retrospective study, tapered internal implants featuring an 11° Morse taper and internal hex connection with SA surfaces demonstrated excellent long-term clinical outcomes. Among the evaluated factors, only sex had a significant influence on implant survival. To better identify risk factors, future multicenter prospective studies with randomized designs are recommended.

The sustained release and bone tissue-specific localization of bone morphogenetic protein 2 (BMP-2) are crucial factors in overcoming the shortcomings in its clinical use. In a previous study, we introduced a bone-targeted, lipoplex-loaded, three-dimensional (3D) bioprinted bilayer scaffold, termed polycaprolactone-bioink-nanoparticle (PBN). We confirmed the bone-specific and sustained release of BMP-2 with PBN in silico and in vitro and demonstrated improved bone formation in vivo. In this study, we evaluated the bone-regenerative effect of PBN combined with bone-inducing drugs in the beagle 3-wall defect model, aiming to facilitate their stable and active application in clinical settings. Surgical defects were created on both sides of the beagle mandible after 4 weeks of teeth extraction (P2, P3, and P4), assigning four groups: (1) control, no scaffold; (2) BMP-2, BMP-2-loaded collagen; (3) PBN/BMP/5-aza-dC, BMP-2, 5-aza-2'-deoxycytidine (5-aza-dC) loaded PBN scaffold; and (4) PBN/5-aza-dC, 5-aza-dC-loaded PBN scaffold. At 4 and 8 weeks postoperatively, the beagles were sacrificed, and radiographic and histological analyses were performed. The micro-computed tomography analysis revealed that the PBN/BMP/5-aza-dC and PBN/5-aza-dC groups showed significant increases in volume density and bone mineral density between 4 and 8 weeks postoperatively (p < 0.05). The BMP-2 and PBN/BMP/5-aza-dC groups showed significantly more mineralized tissue 4 weeks postoperatively, and the largest amount of mineralized tissue was detected after 8 weeks. Based on these results, we suggest that the PBN scaffold would be a good carrier for bone-inducing drugs with bone-tissue specificity and sustained release, especially BMP-2, to reduce clinical side effects.

Bovine or porcine xenografts, which are readily available and possess osteoconductivity, are widely used for bone augmentation in clinical practice. The addition of collagen to particulated bone graft material improves handling characteristics and helps maintain graft integrity. These collagenated bone, when collagen is appropriately cross-linked, provide enhanced osteogenic potential and structural stability. However, studies on the histological changes due to the use of collagenated bovine bone for vertical bone augmentation are lacking. Therefore, this study aimed to compare the osteoconductivity and volume stability of two collagenated xenografts—deproteinized bovine bone mineral (DBBM) with crosslinked bovine collagen (DBBM-Cb; A-Oss Collagen) and non-crosslinked porcine collagen (DBBM-NCp; Bio-Oss Collagen)—using rabbit calvarial models of vertical augmentation and critical-sized defects. Surface morphology of the grafts was analyzed using field emission scanning electron microscopy. In vivo bone regeneration was assessed using micro-computed tomography and histological analyses at 3, 5, 6, and 12 weeks following bone grafting in calvarial vertical-augmentation and defect models. Both grafts showed porous and interconnected microarchitecture favorable for osteoconduction. In the augmentation model, DBBM-Cb demonstrated significantly higher bone volume fraction (bone volume/total volume of bone tissue) at 3 weeks and vertical height retention at both 3 and 5 weeks (P < 0.05). In the defect model, DBBM-Cb led to significantly greater defect closure at 12 weeks (P < 0.05). Histological analyses confirmed improved graft integration and bone maturation with DBBM-Cb. DBBM-Cb exhibited superior osteoconductivity, structural stability, and graft volume maintenance compared to DBBM-NCp. These properties support its potential as a more effective biomaterial for vertical bone augmentation.

BACKGROUND:In elderly patients, bone regeneration is impeded by age-related shifts in mesenchymal stem cell differentiation propensity toward adipogenesis over osteogenesis. We investigated whether DNA demethylation by 5‑aza‑2'‑deoxycytidine (5azaC) synergizes with Wnt Family Member 3A (Wnt3a) signaling to induce osteogenic potential in 3T3‑L1 pre-adipocytes, generating osteoblast-like cells. METHODS:3T3‑L1 pre-adipocytes were treated with 5azaC and/or Wnt3a. Osteogenic differentiation was assessed via ALP activity, mineralization assays, and marker expression. Transcriptomic and epigenomic profiling were performed and compared with MC3T3-E1 cells. Functional relevance of candidate genes was examined using siRNA knockdown. RESULTS:Transcriptomic and epigenomic profiling revealed that 5azaC and Wnt3a co-treatment induced broader gene expression and methylation changes than either treatment alone, closely resembling the osteogenic profile of MC3T3-E1 pre-osteoblasts. Among the overlapping differentially methylated and steadily expressed genes, Tyrosine 3-Monooxygenase/Tryptophan 5-Monooxygenase Activation Protein Eta (Ywhah) and Tyrosine 3-Monooxygenase/Tryptophan 5-Monooxygenase Activation Protein Epsilon (Ywhae) emerged as key regulators, whose knockdown notably enhanced Alpl expression even without 5azaC. CONCLUSIONS:Combining 5azaC-induced demethylation with Wnt3a is a potent strategy to redirect pre-adipocytes toward osteogenesis. Identification of key targets like Ywhah and Ywhae provides mechanistic insight into trans-differentiation and suggests therapeutic potential for bone regeneration, particularly in elderly periodontal patients.

PURPOSE:A small magnetic peg, named "BracketPeg," has been developed as an attachment magnet for implant prostheses. This study aimed to determine the feasibility of measuring implant stability at the prosthesis level, evaluate the reliability and accuracy of BracketPeg, and examine the consistency of measurements obtained using other devices for damping capacity assessment (DCA) and resonance frequency analysis (RFA). METHODS:Forty implants were installed into artificial bone blocks, with each block representing 1 of 4 different diameters (3.5, 4.0, 4.5, and 5.5 mm; 10 implants per diameter). Each implant was paired with a customized zirconia prosthesis that matched the implant diameter. Implant stability was measured at both the fixture and prosthesis levels using Anycheck™ (Neobiotech) for DCA and Osstell™ Beacon (W&H) and ChecQ™ (Dentis) for RFA. To obtain prosthesis-level measurements using RFA devices, BracketPeg was attached to the coronal, middle, and apical thirds of the prosthesis to evaluate implant stability. RESULTS:The implant stability quotient (ISQ) was significantly lower at the prosthesis level than at the fixture level (P<0.001), reflecting the impact of the increased mass and size of the prosthesis. RFA values varied depending on the position of BracketPeg, with lower stability values observed at the coronal position than at the apical position. The 2 RFA devices demonstrated reasonable agreement between ISQ measurements, with a mean difference of -0.58 (95% confidence interval: ±0.31). CONCLUSIONS:BracketPeg provides reliable and consistent implant stability measurements at the prosthesis level compared to other devices, making it a practical and feasible tool for the clinical evaluation of implants.