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Objective To study the clinical outcomes of implanting platelet rich fibrinogen (PRF) mixed with Bio-Oss® in the extraction socket for alveolar ridge preservation and to provide evidence for clinical application. Methods Thirty-six patients who underwent alveolar ridge preservation were enrolled. Thirty-six extraction sites were divided into two groups: PRF mixed with Bio-Oss® group (test group) and Bio-Oss® alone (control group). Bone dimensional changes in height and width were measured by CBCT before and 6 months after surgery, and early soft tissue healing and postoperative pain sensation were evaluated clinically 1 week after surgery. Results There was no significant difference in the alveolar bone height (-1.48 ± 0.40) mm between the test group and the control group. The difference in the alveolar bone width between the test group (-1.09 ± 0.42) mm and the control group (-1.35 ± 0.22) mm was statistically significant (z=-2.63, P=0.01). The postoperative pain score of the test group was 2.39 ± 1.20, and that of the control group was 3.39 ± 1.65, the difference was statistically significant (t=-2.083, P=0.045). There was no significant difference in soft tissue healing between the test group and the control group. Conclusion The use of PRF mixed with Bio-Oss ®in the alveolar ridge preservation procedure can reduce alveolar bone absorption and postoperative pain.

Objective To investigate the clinical effect of a titanium⁃zirconium small⁃diameter implant in anterior teeth with bone deficiencies in the esthetic area and to provide a basis for clinical application of this implant. Meth⁃ ods A retrospective analysis was performed using clinical data from 30 patients with a missing alveolar ridge width < 5.5 mm and a titanium⁃zirconium 3.3 mm diameter implant prosthesis in the anterior esthetic region. A total of 38 titani⁃ um⁃zirconium implants with a diameter of 3.3 mm were implanted in 30 patients. Clinical examination and CBCT were performed 12 and 24 months after implantation to evaluate the success rate and marginal bone resorption of the 3.3 mm small⁃diameter titanium⁃zirconium implants. The modified plaque index, improved gingival sulcus bleeding index, explo⁃ ration depth, pink esthetic score (PES) and prosthetic complications were measured and recorded. Results The 24⁃ month success rate of the implant was 100%. The average marginal bone resorption height was 0.51 ± 0.20 mm at 12 months after implant placement and 0.59 ± 0.18 mm at 24 months. The edge bone height did not change significantly (t＝ 1.381, P＝0.178). No significant differences were found in the modified plaque index around the implant, modified sul⁃ cus bleeding index and probing depth between 12 and 24 months (P > 0.05), and the gingival health was good. The PES value was 9.77 ± 1.48 at 12 months and 10.77 ± 1.50 at 24 months (t＝0.426, P＝0.672). The PES was increased at 24 months versus 12 months, but this difference was not significant (P > 0.05). The overall esthetic effect was good, and no complications occurred after repair. Conclusion Titanium⁃zirconium small⁃diameter implants can achieve good short⁃ term clinical results in the esthetic area of the anterior teeth.

In clinical terms, bone grafting currently involves the application of autogenous, allogeneic, or xenogeneic bone grafts, as well as natural or artificially synthesized materials, such as polymers, bioceramics, and other composites. Many of these are associated with limitations. The ideal scaffold for bone tissue engineering should provide mechanical support while promoting osteogenesis, osteoconduction, and even osteoinduction. There are various structural complications and engineering difficulties to be considered. Here, we describe the biomimetic possibilities of the modification of natural or synthetic materials through physical and chemical design to facilitate bone tissue repair. This review summarizes recent progresses in the strategies for constructing biomimetic scaffolds, including ion‐functionalized scaffolds, decellularized extracellular matrix scaffolds, and micro‐ and nano‐scale biomimetic scaffold structures, as well as reactive scaffolds induced by physical factors, and other acellular scaffolds. The fabrication techniques for these scaffolds, along with current strategies in clinical bone repair, are described. The developments in each category are discussed in terms of the connection between the scaffold materials and tissue repair, as well as the interactions with endogenous cells. As the advances in bone tissue engineering move toward application in the clinical setting, the demonstration of the therapeutic efficacy of these novel scaffold designs is critical. [ABSTRACT FROM AUTHOR]

Objective To prepare sodium alginate-nanohydroxyapatite composite material and to explore its feasibility as a bone repair material. Methods Sodium alginate-nanohydroxyapatite composite material was prepared using chemical cross-linking and freeze-drying technology. The composite was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) and its porosity was measured by liquid displacement method. The fifth passage of bone marrow stromal stem cells (BMSCs) were incubated on the composite material and then growth was observed by inverted microscope and SEM. BMSCs were cultured with liquid extracts of the material, methyl thiazolyl tetrazolium (MTT) assay was used to calculate the relative growth rate (RGR) on 1, 3, 5 d and to evaluate the cytotoxicity. Fresh dog blood was added into the liquid extracts to conduct hemolysis test, the spectrophotometer was used to determine the optical density (OD) and to calculate the hemolysis rate. Results Sodium alginate-nanohydroxyapatite composite material displayed porosity, the porous pore rate was (88.6±4.5)%. BMSCs showed full stretching and vigorous growth under inverted microscope and SEM. BMSCs cultured with liquid extracts of the material had good activities. The toxicity of composite material was graded as 1. Hemolysis test results showed that the hemolysis rate of the composite material was 1.28%, thus meeting the requirement of medical biomaterials. Conclusion The composite material fabricated in this study has high porosity and good biocompatibility. [ABSTRACT FROM AUTHOR]

A novel porous graphene oxide (GO)/chitosan (CTS)-hydroxyapatite (HA) nanocomposite film was successfully prepared for the first time by combining layer-by-layer (LBL) assembly technology with biomimetic mineralization method. The LBL technology was used to control the thickness of film as well as induce the biomimetic mineralization of biocompatible HA. The obtained (GO/CTS-HA) n film provided ideal platform for the proliferation of mouse mesenchymal stem cells (mMSCs). The pore size in the film is about 300 nm, and the porous architecture made the film have high aspirin loading efficiency. Also the accumulated loading dosage could be adjusted by the film thickness, and the sustained release of aspirin could ensure well anti-inflammatory effect. The above advantages may alleviate the pain of patients and give the better environment for bone regeneration. This multifunctional aspirin-loaded (GO/CTS-HA) n film provided an inspiration for the synthesis of novel porous inorganic/biomacromolecule nanocomposite films as the biocoatings applied in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Objective: The aim of this population-based retrospective study was to compare the osteogenic effect of newly formed bone after maxillary sinus floor elevation (MSFE) and simultaneous implantation with or without bone grafts by quantitatively analyzing trabecular bone parameters., Methodology: A total of 100 patients with missing posterior maxillary teeth who required MSFE and implantation were included in this study. Patients were divided into two groups: the non-graft group (n=50) and the graft group (n=50). Radiographic parameters were measured using cone beam computed tomography (CBCT), and the quality of newly formed bone was analyzed by assessing trabecular bone parameters using CTAn (CTAnalyzer, SkyScan, Antwerp, Belgium) software., Results: In the selected regions of interest, the non-graft group showed greater bone volume/total volume (BV/TV), bone surface/total volume (BS/TV), trabecular number (Tb. N), and trabecular thickness (Tb. Th) than the graft group (p<0.001). The non-graft group showed lower trabecular separation (Tb. Sp) than the graft group (p<0.001). The incidence of perforation and bleeding was higher in the graft group than in the non-graft group (p<0.001), but infection did not significantly differ between groups (p>0.05). Compared to the graft group, the non-graft group showed lower postoperative bone height, gained bone height and apical bone height (p<0.001)., Conclusion: MSFE with and without bone grafts can significantly improve bone formation. In MSFE, the use of bone grafts hinders the formation of good quality bone, whereas the absence of bone grafts can generate good bone quality and limited bone mass.

Bone marrow mesenchymal stem cells (BMSCs) of rats were isolated and Bio-Oss ® and R.T.R ® materials were used in this study.Alkaline phosphatase (ALP) activity in each group was calculated. The ability of adhesion and proliferation of BMSCs on Bio-Oss ® and R.T.R ® increased with time, but they were significantly higher on R.T.R ® than that of Bio-Oss ® at all time points (p<0.05). Compared with Bio-Oss ® , R.T.R ® could promote the expression and activity of ALP in BMSCs, and the expression of bone formation related transcription factors bone morphogenetic protein-1 (BMP-1), Cbfa1 and osteoblast marker genes ALP, collagen I, osteopontin, osseomucin and osteocalcin. The expression levels of cbfa1, ALP, collagen I, osteopontin, osseomucin and osteocalcin were inhibited after downregulated expression of BMP-1 in BMSCs and inoculation with R.T.R ® . R.T.R ® could up-regulate BMP-1 expression and cbfa1 expression through BMPs/SMAD signaling pathway, thereby promoting the expression of ALP, collagen I, osteopontin, osseomucin and osteocalcin and promoting osteoblast differentiation.

Considering the chemical exchange between gadolinium centers and water protons, nanosystems comprising gadolinium conjugated with high specific area nanocarriers might serve as more robust clinical tools for diagnosis and imaging-guided therapy. Herein, a pH-responsive nanosystem containing graphene oxide conjugated with a folic acid- and gadolinium-labeled dendrimer (FA-GCGLD) to boost its T 1 contrast ability was developed, and doxorubicin (DOX) and colchicine (COLC) were efficiently loaded onto this nanosystem (FA-GCGLD-DOX/COLC). This nanosystem showed a prominent T 1 contrast with an ultrahigh relaxivity of up to 11.6 mM -1 s -1 and pH-responsive drug release behavior. HepG2 cells treated with FA-GCGLD-DOX/COLC were efficiently inhibited, and the cell contrast was enhanced. In vivo, the tumor accumulation of FA-GCGLD-DOX/COLC significantly increased, thereby facilitating the systemic delivery of particles and exerting tumor growth inhibition and an enhanced tumor contrast effect. Moreover, compared to free drugs, FA-GCGLD-DOX/COLC effectively decreased the drug resistance of the tumor, thereby improving the cancer chemotherapeutic efficacy. In addition, injecting rats with FA-GCGLD afforded excellent magnetic resonance angiography (MRA) images with high-resolution vascular structures because of the long blood circulation time of FA-GCGLD. Thus, this study provides a powerful tool for diverse applications in the biomedical field, including accurate diagnosis and chemotherapy of tumors and the detection of cardiovascular diseases.

Objective: To prepare sodium alginate-nanohydroxyapatite composite material and to explore its feasibility as a bone repair material., Methods: Sodium alginate-nanohydroxyapatite composite material was prepared using chemical cross-linking and freeze-drying technology. The composite was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) and its porosity was measured by liquid displacement method. The fifth passage of bone marrow stromal stem cells (BMSCs) were incubated on the composite material and then growth was observed by inverted microscope and SEM. BMSCs were cultured with liquid extracts of the material, methyl thiazolyl tetrazolium (MTT) assay was used to calculate the relative growth rate (RGR) on 1, 3, 5 d and to evaluate the cytotoxicity. Fresh dog blood was added into the liquid extracts to conduct hemolysis test, the spectrophotometer was used to determine the optical density (OD) and to calculate the hemolysis rate., Results: Sodium alginate-nanohydroxyapatite composite material displayed porosity, the porous pore rate was (88.6 +/- 4.5)%. BMSCs showed full stretching and vigorous growth under inverted microscope and SEM. BMSCs cultured with liquid extracts of the material had good activities. The toxicity of composite material was graded as 1. Hemolysis test results showed that the hemolysis rate of the composite material was 1.28%, thus meeting the requirement of medical biomaterials., Conclusion: The composite material fabricated in this study has high porosity and good biocompatibility.

Objective: To investigate the effectiveness of the medical calcium sulfate-OsteoSet bone graft substitute in the treatment of defect after excision of jaw cyst., Methods: Between December 2009 and May 2010, 15 cases of jaw cystic lesion were treated, including 9 males and 6 females with an average age of 36.6 years (range, 15-75 years). Orthopantomography (OPT) method was used to measure the cyst size before operation, and the size ranged from 1.5 cm x 1.5 cm to 8.0 cm x 3.0 cm. The range of bone defect was from 1.5 cm x 1.5 cm x 1.5 cm to 8.0 cm x 3.0 cm x 3.0 cm after cyst excision intraoperatively. The patients underwent cyst curettage and OsteoSet bone graft substitutes implantation (2-15 mL). Radiological method was used to evaluate the repair effect of OsteoSet pellets., Results: The pathology biopsy was periapical cyst in 7 cases, odontogenic keratocyst in 5 cases, and dentigerous cyst in 3 cases. Fifteen patients were followed up 6-12 months. Thirteen patients achieved wound healing by first intention; 2 cases had longer drainage time (5 and 7 days, respectively), the incision healed after the pressure bandage. Swelling occurred in 1 case after 1 month with no symptom of infection. No postoperative infection and rejection was found. The X-ray examination showed that the materials filled the bone defect well after 1 day of operation. OsteoSet bone graft substitutes were absorbed by one-half after 1 month of operation and totally after 3 months by OPT. The low density area was smaller in the original cysts cavity, and high density in the cysts increased significantly with fuzzy boundaries of cysts. At 6 months after operation, there was no obvious difference in image density between the original cavity and normal bone, and the capsule cavity boundary disappeared, and defect area was full of new bone., Conclusion: The medical calcium sulfate-OsteoSet bone graft substitute is an ideal filling material for bone defect.