A GP130-Targeting Small Molecule, LMT-28, Reduces LPS-Induced Bone Resorption around Implants in Diabetic Models by Inhibiting IL-6/GP130/JAK2/STAT3 Signaling.

In this study, we examined the effect of the GP130-targeting molecule, LMT-28, on lipopolysaccharide- (LPS-) induced bone resorption around implants in diabetic models using in vitro and rat animal experiments. First, LMT-28 was added to osteoblasts stimulated by LPS and advanced glycation end products (AGEs), and nuclear factor-κB receptor-activating factor ligand (RANKL) and associated pathways were evaluated. Then, LMT-28 was administered by gavage at 0.23 mg/kg once every 5 days for 2 weeks to type 2 diabetic rats with peri-implantitis induced by LPS injection and silk ligature. The expression of IL-6 and RANKL was evaluated by immunohistochemistry, and the bone resorption around implants was evaluated by microcomputed tomography. The results showed that LMT-28 downregulated the expression of RANKL through the JAK2/STAT3 signaling pathway in osteoblasts stimulated by LPS and AGEs, reduced bone resorption around implants with peri-implantitis, decreased the expression of IL-6 and RANKL, and decreased osteoclast activity in type 2 diabetic rats. This study confirmed the ability of LMT-28 to reduce LPS-induced bone resorption around implants in diabetic rats.

Increased bio-toxicity of leachates from polyvinyl chloride microplastics during the photo-aging process in the presence of dissolved organic matter.

The pollution caused by microplastics (MPs) has gained global attention due to their potential risks to organisms and human health. The process of photo-aging, which plays a crucial role in the transformation of MPs in aquatic environments, has the potential to influence the ecological risk posed by these particles. Dissolved organic matter (DOM) is a prevalent photosensitizer in surface waters that has been shown to facilitate the transformation of various organic compounds by generating reactive oxygen species under light irradiation. The present study investigated the influence of humic acid (HA), a typical component of DOM, on the photo-aging process of polyvinyl chloride MPs (PVC-MPs), using Fourier transform infrared spectroscopy, as well as assessing the resulting ecological risk through bioassays. The results revealed that the presence of HA enhanced the photo-aging of PVC-MP. Moreover, the leachate exhibited higher acute and genetic toxicity under light irradiation when compared to dark conditions. Notably, the presence of HA significantly increased the toxicity of the leachate, emphasizing the need to consider the impact of DOM when assessing the ecological risk of MPs in surface waters. These findings contribute to a more comprehensive understanding of the potential risks associated with microplastic pollution in natural environments.

HOXA10 inhibit the osteogenic differentiation of periodontal ligament stem cells by regulating ß-catenin localization and DKK1 expression.

Introduction: Human periodontal ligament stem cells (hPDLSCs) are stem cells found near the tooth periodontal ligament. These cels are involved in the regeneration of the periodontal ligament and alveolar bone during orthodontic treatment and chronic periodontitis.Objectives: The Homeobox gene HOXA10 regulates the osteogenic differentiation of stem cells. However, the role of HOXA10 in hPDLSCs remains unclear. Therefore, we studied the effects of HOXA10 on human PDLSC osteogenic differentiation in vitro.Methods: First, hPDLSCs were isolated and characterized. Second, we assessed the effects of overexpression and knockdown of HOXA10 on PDLSC osteogenic differentiation. Finally, the specific Wnt signaling pathway activator lithium chloride (LiCl) and inhibitor ICG-001 were used to investigate the involvement of the Wnt signaling pathway in HOXA10-induced regulation of osteogenic differentiation.Results: Overexpressing HOXA10 inhibited PDLSC osteogenic differentiation in vitro, shown by ALP and Alizarin Red staining, while HOXA10 knockdown demonstrated the opposite effects. HOXA10 negatively regulated nuclear ß-catenin and osteogenic differentiation markers including alkaline phosphatase (ALPL) and integrin-binding sialoprotein (IBSP). Upregulating HOXA10 reduced nuclear ß-catenin and increased DKK1 expression. However, HOXA10 knockdown enhanced nuclear ß-catenin accumulation and reduced DKK1 expression. These negative effects on osteogenic differentiation by HOXA10 overexpression were restored by the Wnt/ß-catenin pathway activator LiCl. The increased osteogenic differentiation effects of HOXA10 knockdown were antagonized by ICG-001, a Wnt pathway inhibitor.Conclusion: These data demonstrate that HOXA10 inhibits the osteogenic differentiation of periodontal ligament stem cells by regulating ß-catenin localization and DKK1.

Automated µFTIR Imaging Demonstrates Taxon-Specific and Selective Uptake of Microplastic by Freshwater Invertebrates.

Microplastic particles can be deposited to sediments and subsequently ingested by benthic organisms. It is unknown to what extent ingestion of microplastic is taxon-specific or whether taxa can be selective toward certain types of microplastics. Here, we used state-of-the-art automated micro-Fourier-transform infrared (µFTIR) imaging and attenuated total reflectance FTIR spectroscopy to determine small-size (20-500 µm) and large-size (500-5000 µm) microplastic particles in sediments and a range of benthic invertebrate species sampled simultaneously from the Dommel River in the Netherlands. Microplastic number concentrations differed across taxa at the same locations, demonstrating taxon-specific uptake, whereas size distributions were the same across sediments and taxa. At the site with the highest concentration, microplastic occupied up to 4.0% of the gut volume of Asellidae. Particle shape distributions were often not statistically different between sediments and taxa, except for Astacidea at one of the locations where the proportion of particles with a length to width ratio >3 (i.e., fibers) was twice as high in sediments than in Astacidea. Acrylates/polyurethane/varnish was predominately found in sediments, while soft and rubbery polymers ethylene propylene diene monomer and polyethylene-chlorinated were the dominant polymers found in invertebrates. Microplastic polymer composition and thus polymer density differed significantly between invertebrates and their host sediment. Trophic transfer at the base of the food web appears to have a filter function with respect to microplastic particle types and shapes. Together with the very high ingestion rates, this has clear implications for ecological and human health risks, where uptake concerns edible species (e.g., Astacidea).

Evaluation of Resorption and Osseointegration of Autogenous Bone Ring Grafting in Vertical Bone Defect With Simultaneous Implant Placement in Dogs.

The aim of this research was to evaluate the resorption and osseointegration of an autogenous bone ring, which was grafted in a local vertical alveolar defect with simultaneous implant placement. Six Beagle dogs were enrolled in the study; their 4 nonadjacent mandibular premolars were extracted, and the buccal plate was removed to create bone defects in 2 of the 4 sites. Three months after extraction, Straumann implants (Ø 3.3 mm, length of 8 mm) were placed in the bone defect sites with simultaneous autogenous bone ring grafting and in the conventional extraction sites. After a 3-month healing period and a 3-month loading period, the animals were euthanized. The harvested samples were analyzed using micro-computed tomography (CT) scanning and histological analysis. From the micro-CT measurements, the average vertical bone resorption of the bone ring was 0.23 ± 0.03 mm, which was not significantly different from that around the conventional implant, 0.24 ± 0.12 mm (P > .05). The ratio of the bone volume to the total volume of the bone ring group was 91.11 ± 0.02, which was higher than that of the control group, 88.38 ± 2.34 (P < .05). From the hard tissue section, the bone rings developed fine osseointegration with the implants and the base alveolar bone. The results suggest autogenous bone ring grafting with simultaneous implant placement can survive in a local vertical bone defect with little bone resorption and good osseointegration in dogs with strict management. A bone ring graft must be compared with guided bone regeneration, and a larger and longer observation must be confirmed in clinical patients.

[Effects of GBR and Delayed Loading on Bone Ring Grafting with Simultaneous Implant Insertion: an Experimental Study on Beagle Dogs].

OBJECTIVE: To determine the effects of guided bone regeneration (GBR) and delayed loading on autogenous bone ring grafting. METHODS: Autogenous bone ring augmentation with simultaneous implant insertion was performed in the mandibular premolars region of six Beagle dogs. The Bone quality of four mandibular premolars [second premolar (P2) and fourth premolar (P4)] were detected using cone beam CT (CBCT). The P2s and P4s of bilateral mandible were extracted, with three extracting sites being randomly selected to create buccal defects and the remaining one serving as control. GBR and bone ring grafting with simultaneous implant insertion was performed on two of the three experimental sites with buccal defects 3 months later, while the other one was treated with bone ring grafting with simultaneous implant insertion. Routine implant placement was performed in the control group. Vertical bone resorption and sulcus deep around the implants were measured three months after occlusal loading with abutment. RESULTS: Three months after operations, 83.3% of bone rings grafts were successful and 100% of implants survived. Delayed healing appeared more in the dogs with GBR compared those treated with bone ring grafting with simultaneous implant insertion, resulting in an increase in vertical bone resorption. Compared with the control group, delayed loading had no effects on vertical bone resorption and the health of gingiva tissues after autogenous bone ring transplant. CONCLUSION: GBR is not a preferred procedure for bone ring grafts, which may increase the risk of delayed healing and site infections, leading to failure of implants. Healed bone ring grafts can resist loadings as normal.

IL-6 Inhibitor Tocilizumab Reduces Bone Resorption Around Implants with Bacterial Infection During Osseointegration: A Pilot Study in Rabbits.

PURPOSE: To evaluate the effect of interleukin-6 (IL-6) inhibitor (tocilizumab) on bacterial infection-associated bone resorption around implants during osseointegration in rabbits. MATERIALS AND METHODS: At total of 24 male, 9-monthold New Zealand white rabbits were included, and their two mandibular anterior teeth were extracted. Three months after extraction, 24 one-piece Dentium implants (Ø 2.5 mm, intraosseous length of 12 mm) were inserted in the anterior mandible, and the rabbits were divided into four groups (n = 6 per group). Different treatment methods were used in each group: blank control group (BC); only silk ligation (negative control [NC]); silk ligation and injection with minocycline hydrochloride ointment (positive control [PC]); and silk ligation and injection with tocilizumab at 8 mg/kg via the auricle vein (experimental [EP]). Eight weeks later, the animals were sacrificed, and samples were collected and then analyzed using microcomputed tomography (microCT) scanning, immunohistochemical analysis, and histologic analysis. RESULTS: From the microCT measurement, the ratio of the bone volume to the total volume (BV/TV) in the EP group was 67.00% ± 2.72%, which was higher than that in the other three groups (58.85% ± 2.43% in the BC group, 55.72% ± 2.48% in the PC group, and 36.52% ± 3.02% in the NC group). From immunohistochemical analysis, the expression of IL-6 was found to be higher in the NC group than in the BC, PC, and EP groups, but there was no statistical difference between these three groups. Furthermore, the RANKL (receptor activator of nuclear factor-κB ligand) expression was the lowest in the EP group, followed by the BC group, the PC group, and the NC group, which had the highest expression; there was no difference between the NC and PC groups. Upon histologic analysis, significant new bone was found on the implant surfaces in the EP group, sparse and less new bone could be seen in the BC and PC groups, and the most serious bone resorption occurred in the NC group. CONCLUSIONS: Tocilizumab, an inhibitor of IL-6, has a certain effect in preventing bone loss around implants caused by bacterial infection during the osseointegration period.

Reamer-scraping and implant-pushing technique for transcrestal sinus floor elevation.

Transcrestal maxillary sinus floor elevation is an effective method to solve the problem of insufficient bone height in the posterior maxillary region. However, current methods, such as osteotome sinus floor elevation, cushioned grind-out technique, Smart Drill technique, etc., require specialized surgical tool boxes. In this article, we introduce a new method of transcrestal maxillary sinus elevation that uses built-in reamers of various implant systems to scrap residual bone at the sinus floor and uses the implant to push the sinus membrane during implant placement. This technique is easy to operate and time saving and has a low rate of sinus membrane perforation. After a one-year follow-up observation of 146 people and 175 implants, the endo-sinus bone gains were 5.00 (4.70, 5.30) mm and 2.10 (1.40, 2.70) mm in the group of 3 mm≤residual bone height (RBH)<5 mm and the group of 5 mm≤RBH<8 mm, respectively, which can meet the clinical requirements of implant stability. This technique is suitable in generalizing dental implantation.

Accuracy evaluation of a universal dental implant guide for simulating implantation in posterior area on dental molds.

OBJECTIVES: This study aims to compare the accuracy of self-developed universal implant guide (SDG), 3D printed digital guide (DG), and free hand (FH) simulated implantation in the posterior tooth area of dental models. METHODS: Ten junior dentists were selected to place three implants in the 35, 37, and 46 tooth sites of the mandibular models (35, 36, 37, and 46 missing teeth) by using SDG, DG, and FH, and the process was repeated again to take the average value. Cone beam computed tomography (CBCT) was used to evaluate the global coronal deviation, global apical deviation, depth deviation, and angular deviation between the actual position and preoperative planned position. RESULTS: The coronal deviation and apical deviation of the three implant sites in the SDG group were not significantly different from those in the two other groups (P>0.05). The depth deviation and angular deviation in the SDG group were smaller than those in the DG group (P<0.05) and FH group (P<0.05), respectively. All deviations at site 37 in the SDG group were not different from those at site 35 (P>0.05), while the depth and angular deviation at site 37 in the DG group were higher than those at site 35 (P<0.05). CONCLUSIONS: The precision of the self-developed universal dental implant guide can meet the requirements of clinical posterior implantation.

Integrative Dissection of Lignin Composition in Tartary Buckwheat Seed Hulls for Enhanced Dehulling Efficiency.

The rigid hull encasing Tartary buckwheat seeds necessitates a laborious dehulling process before flour milling, resulting in considerable nutrient loss. Investigation of lignin composition is pivotal in understanding the structural properties of tartary buckwheat seeds hulls, as lignin is key determinant of rigidity in plant cell walls, thus directly impacting the dehulling process. Here, the lignin composition of seed hulls from 274 Tartary buckwheat accessions is analyzed, unveiling a unique lignin chemotype primarily consisting of G lignin, a common feature in gymnosperms. Furthermore, the hardness of the seed hull showed a strong negative correlation with the S lignin content. Genome-wide detection of selective sweeps uncovered that genes governing the biosynthesis of S lignin, specifically two caffeic acid O-methyltransferases (COMTs) and one ferulate 5-hydroxylases, are selected during domestication. This likely contributed to the increased S lignin content and decreased hardness of seed hulls from more domesticated varieties. Genome-wide association studies identified robust associations between FtCOMT1 and the accumulation of S lignin in seed hull. Transgenic Arabidopsis comt1 plants expressing FtCOMT1 successfully reinstated S lignin content, confirming its conserved function across plant species. These findings provide valuable metabolic and genetic insights for the potential redesign of Tartary buckwheat seed hulls.

Dental implant failure rates with low insertion torque with a nonsubmerged surgical approach: A retrospective clinical study.

BACKGROUND: It is currently unclear if a low insertion torque (IT) should prompt a clinician to submerge the dental implant at time of placement. PURPOSE: This study aimed to analyze implant failure rates and marginal bone loss (MBL) as a function of IT and surgical approach. MATERIALS AND METHODS: A total of 197 patients who had received 295 Mozo Grau (MG) implants were included in this study. The healing of submerged or nonsubmerged implants was evaluated in regular IT (≥20-25 Ncm) or low IT (<20-25 Ncm) cases. Implant failure and MBL were evaluated before prosthesis placement and at 6 and 12 months after functional loading with generalized estimating equations. RESULTS: The overall 12-month implant failure rate was 4.8% (95% confidence interval [CI]: 2.7%-8.2%). When successful at 12 months, dental implants placed with low IT and nonsubmerging had the same MBL as implants dental implants placed with other approaches (mean difference = -0.02 mm; 95% CI -0.05 to 0.02). Low IT combined with nonsubmerging of the dental implant was associated with a 30-fold increased odds for dental implant failure (95% CI: 3.8-236.6). CONCLUSION: low IT and nonsubmerged healing was associated with a high failure rate.

VAMP726 from maize and Arabidopsis confers pollen resistance to heat and UV radiation by influencing lignin content of sporopollenin.

Sporopollenin in the pollen cell wall protects male gametophytes from stresses. Phenylpropanoid derivatives, including guaiacyl (G) lignin units, are known to be structural components of sporopollenin, but the exact composition of sporopollenin remains to be fully resolved. We analyzed the phenylpropanoid derivatives in sporopollenin from maize and Arabidopsis by thioacidolysis coupled with nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS). The NMR and GC-MS results confirmed the presence of p-hydroxyphenyl (H), G, and syringyl (S) lignin units in sporopollenin from maize and Arabidopsis. Strikingly, H units account for the majority of lignin monomers in sporopollenin from these species. We next performed a genome-wide association study to explore the genetic basis of maize sporopollenin composition and identified a vesicle-associated membrane protein (ZmVAMP726) that is strongly associated with lignin monomer composition of maize sporopollenin. Genetic manipulation of VAMP726 affected not only lignin monomer composition in sporopollenin but also pollen resistance to heat and UV radiation in maize and Arabidopsis, indicating that VAMP726 is functionally conserved in monocot and dicot plants. Our work provides new insight into the lignin monomers that serve as structural components of sporopollenin and characterizes VAMP726, which affects sporopollenin composition and stress resistance in pollen.

Antifouling poly(PEGMA) grafting modified titanium surface reduces osseointegration through resisting adhesion of bone marrow mesenchymal stem cells.

As an alternative strategy to achieve the desired bone augmentation, tenting screw technology (TST) has considerably broadened the indications for implant treatment. Titanium tenting screws are typically used in TST to maintain the space for bone regeneration. However, a high degree of osteogenic integration complicate titanium tenting screw removal and impact the bone healing micro-environment. Previous efforts have been focused on modifying titanium surfaces to enhance osseointegration while ignoring the opposite process. Due to the vital role of bone marrow mesenchymal stem cells (BMSCs) in bone regeneration, it might be feasible to reduce osseointegration around titanium tenting screws by resisting the adhesion of BMSCs. Herein, poly(ethylene glycol)methyl ether methacrylate (poly(PEGMA)) with an optimal length of PEG chain was incorporated with a Ti surface in terms of surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The cell apoptosis analysis showed that the new surface would not induce the apoptosis of BMSCs. Then, the adhesive and proliferative behaviors of BMSCs on the surface were analyzed which indicated that the poly(PEGMA) surface could inhibit the proliferation of BMSCs through resisting the adhesion process. Furthermore, in vivo experiments revealed the presence of the poly(PEGMA) on the surface resulted in a lower bone formation and osseointegration compared with the Ti group. Collectively, this dense poly(PEGMA) surface of Ti may serve as a promising material for clinical applications in the future. STATEMENT OF SIGNIFICANCE: The poly(ethylene glycol)methyl ether methacrylate (poly(PEGMA)) with an optimal length of PEG chain was grafted onto a Ti surface by surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The PEGMA surface could reduce the osteogenic integration by preventing the adhesion of cells, resulting in a lower pullout force of the modified implant and thereby desirable and feasible applications in dental surgery.

Genetically modified cell sheets in regenerative medicine and tissue engineering.

Genetically modified cell sheet technology is emerging as a promising biomedical tool to deliver therapeutic genes for regenerative medicine and tissue engineering. Virus-based gene transfection and non-viral gene transfection have been used to fabricate genetically modified cell sheets. Preclinical and clinical studies have shown various beneficial effects of genetically modified cell sheets in the regeneration of bone, periodontal tissue, cartilage and nerves, as well as the amelioration of dental implant osseointegration, myocardial infarction, skeletal muscle ischemia and kidney injury. Furthermore, this technology provides a potential treatment option for various hereditary diseases. However, the method has several limitations, such as safety concerns and difficulties in controlling transgene expression. Therefore, recent studies explored efficient and safe gene transfection methods, prolonged and controllable transgene expression and their potential application in personalized and precision medicine. This review summarizes various types of genetically modified cell sheets, preparation procedures, therapeutic applications and possible improvements.

1α,25-dihydroxyvitamin D3 promotes early osteogenic differentiation of PDLSCs and a 12-year follow-up case of early-onset vitamin D deficiency periodontitis.

Periodontitis is a chronic periodontal disease that contributes to tooth loss. In recent years, many animal studies have reported that vitamin D (VitD) deficiency results in chronic periodontitis. However, no studies have reported cases of early-onset periodontitis with VitD deficiency. This study reports a 5-year-old male patient with early-onset periodontitis, VitD deficiency and VitD receptor (VDR) mutation. The patient was treated with VitD and calcium, and received systematic periodontal treatment. During the 12-year treatment, the periodontal conditions of this patient were stable. Our in vitro study found that VitD could promote the expression of alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), bone morphogenetic protein 2 (BMP2), bone gamma-carboxyglutamate protein (BGLAP), and VDR in the early osteogenic differentiation of periodontal ligament stem cells (PDLSCs). Meanwhile, VitD could downregulate mRNA expression levels of Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-1ß (IL-1ß) and protein levels of IL-6 in the tumor necrosis factor-α (TNF-α) -induced inflammation of PDLSCs. Therefore, sufficient VitD supply can be a potential treatment for VitD deficiency induced early-onset periodontitis.

New Incision and Flap Designs in Autogenous Bone Ring Grafting with Simultaneous Implant Placement and an Evaluation of the Effect of First-Stage Wound Dehiscence in Dogs.

PURPOSE: The aim of this study was to explore the effect of preventing first-stage wound dehiscence with new types of incision and flap design and to evaluate the effect of wound dehiscence on the bone resorption of the autogenous bone ring graft. MATERIALS AND METHODS: In six beagle dogs, the second and fourth premolars on the bilateral mandible were extracted. After 3 months, on the left extraction sites, conventional alveolar crest incisions were made and the full-thickness flaps were elevated. However, on the right sites, the incisions were made at the mucogingival junction, the split-thickness flaps were elevated toward the lingual side, and the periosteum was elevated toward the buccal side. Then, Straumann implants (. 3.3, length 8 mm) were placed with simultaneous autogenous bone ring grafting. Next, the wounds on the left side were closed with periosteal releasing on buccal flaps conventionally, but the semi-thickness flaps on the right side were sutured with the elevated periosteum. After 3 months, the animals were euthanized, and the harvested samples were analyzed using microcomputed tomography and histology. RESULTS: The incidence rate of wound dehiscence in the new incision group was 16.7%, which was significantly lower than that in the conventional incision group (75%). There was hardly any vertical bone loss of the bone ring in the samples without wound dehiscence, but in wound dehiscence samples, severe bone loss, 2.47 ± 0.17 mm, was found on the buccal side of the bone ring, which was significantly higher than that on the lingual, mesial, and distal sides, 1.37 ± 0.14 mm, 1.00 ± 0.15 mm, and 1.03 ± 0.05 mm, respectively. CONCLUSION: The use of a mucogingival junction incision and split-thickness flap design can effectively prevent first-stage wound dehiscence in autogenous bone ring grafting, which plays a key role in bone resorption of the graft.

Endoscopically-Assisted Percutaneous Unilateral Atlantoaxial Screw-Rod Nonfusion Fixation Treatment for Type II Odontoid Fractures in Geriatric Patients: Case Series and Technical Note.

BACKGROUND: Considerable controversy exists regarding the optimal treatment for type II odontoid fractures in geriatric patients. Surgical intervention can help patients return to their prior level of function as rapidly as possible while avoiding the morbidity and mortality associated with prolonged and bedbound hospitalization. However, the optimal treatment is still a difficult choice for patients with increased risk from anesthesia. OBJECTIVES: The objective of our study was to describe an innovative method of endoscopically-assisted percutaneous unilateral C1 lateral mass screw and C2 pedicle screw-rod nonfusion fixation for type II odontoid fractures in geriatric patients. STUDY DESIGN: A case series design and technical notes. SETTING: This study took place at Second Affiliated Hospital of Chongqing Medical University. METHODS: Seven geriatric patients (> 65 years) with type II odontoid fractures and an American Society of Anesthesiologists (ASA) score of 2 or higher received endoscopically-assisted percutaneous unilateral atlantoaxial screw-rod nonfusion fixation. After surgery, all patients were required to wear a rigid collar full-time for 12 weeks. Intraoperative data, the bone union time, American Spinal Injury Association (ASIA) scale scores, Neck Disability Index (NDI) scores, and postoperative complications were collected for assessment.RESULTS The surgical goal was successfully achieved in all patients, 3 of whom had high ASA scores (>= 3) and underwent surgery under local anesthesia. The operative time ranged from 112 to 169 minutes (mean, 131.1 minutes). No neurovascular complications were observed intraoperatively or postoperatively. All patients rapidly returned to their prior level of function and were followed up for 12 to 24 months (average: 16.9 months). Bone union was achieved in all patients. LIMITATIONS: This study is limited by being a retrospective study. CONCLUSIONS: Endoscopically-assisted percutaneous unilateral atlantoaxial screw-rod nonfusion fixation is a feasible technique for type II odontoid fractures in geriatric patients. This method offers a compromise between non-operative and operative treatment and allows geriatric patients to rapidly return to their prior level of function. KEY WORDS: Endoscopically-assisted surgery; geriatric patient; percutaneous atlantoaxial fixation; type II odontoid fracture; unilateral nonfusion fixation.

[Advances in the application of machine learning in maxillofacial cysts and tumors].

The application of artificial intelligence in medicine has gradually received attention along with its development. Many studies have shown that machine learning has a wide range of applications in stomatology, especially in the clinical diagnosis and treatment of maxillofacial cysts and tumors. This article reviews the application of machine learning in maxillofacial cyst and tumor to provide a new method for the diagnosis of oral and maxillofacial diseases.

Effect of the Wnt signal-RANKL/OPG axis on the enhanced osteogenic integration of a lithium incorporated surface.

Bone remolding involves the formation of new bone by osteoblasts and the absorption of old bones by osteoclasts. Due to the vital role of osteoblasts and osteoclasts during bone regeneration, it might be feasible to promote osseointegration around the titanium implants by stimulating osteoblasts and inhibiting osteoclasts by modifying the surfaces of the implants. Lithium is used in the treatment of psychiatric patients, and it may be associated with osteogenesis. In this study, lithium was incorporated with sandblasted, large-grit and acid-etched titanium implants via a hydrothermal treatment. In vitro, the nano-scale surface enhanced the adhesion and proliferation of bone marrow mesenchymal stem cells (BMSCs). Moreover, the SLA-Li surface displayed a negative effect on the process of osteoclastogenesis. Further mechanism analysis indicated that the canonical Wnt/ß-catenin signaling pathway was activated according to the results of RT-PCR and western blotting. More importantly, the RANKL/OPG signaling axis was also involved in these effects on the SLA-Li surface. The experiments in vivo proved that the SLA-Li surface could induce the bone formation and osseointegration during the early osseointegration after the dental implant surgery. These results suggested that bone homeostasis could be manipulated by an SLA-Li surface, which implied that this new surface might serve as a promising material for clinical application in the future.

Sustained Release of Antimicrobial Peptide from Self-Assembling Hydrogel Enhanced Osteogenesis.

Biomaterials have been widely used in bone infection and osteomyelitis resulting from their versatile functionalities. As far as we know, the appearance of osteomyelitis was mainly caused by bacteria. Therefore, a biomaterial that can cure bone infection and promote osteogenesis may become an ideal candidate for the treatment of osteomyelitis. Cationic antimicrobial peptides (AMPs) have been proved to have an excellent ability to kill bacteria, fungi, viruses, and parasites. However, the application of AMPs in bone infection and osteomyelitis is quite limited. Here, we designed a new hydrogel that has an inhibitory effect on the proliferation of S. aureus and enhances osteogenesis. RADA16 self-assembling peptide has been applied for AMPs delivery. In this study, we demonstrated that RADA16 could form a stable structure and afford the sustained release of AMPs. The interwoven nanofiber morphology was detected by field emission scanning electron microscopy. The sustained release study revealed that the release of AMPs could be obtained until 28 days. In vitro research showed this new self-assembling hydrogel could promote the proliferation of bone mesenchymal stem cells (BMSCs) and inhibited the growth of S. aureus. More importantly, the results in vivo also proved that RADA16-AMP self-assembling peptide had an excellent effect on bone formation. Our findings implied that we successfully combined RADA16 and AMPs together and laid the foundation for the application of this new hydrogel and open new avenues for biomaterials.