Nonmineralized and Mineralized Silk Fibroin/Gelatin Hybrid Scaffolds: Chacterization and Cytocompatibility In Vitro for Bone-Tissue Engineering.

In this study, nonmineralized silk fibroin/gelatin (SF/G) hybrid scaffolds and the mineralized SF/G/hydroxyapatite (SF/G/HA) hybrid scaffolds were fabricated using vacuum freeze-drying method and biomineralization technique. The morphology and mechanical properties of the 2 hybrid scaffolds were characterized. Furthermore, the cytotoxic profiles of the hybrid scaffolds were investigated in vitro by seeding the human osteoblast cells (hFOB1.19). The 2 hybrid scaffolds were both highly porous and the pore sizes of the SF/G as well as SF/G/HA hybrid scaffolds were 260 ±â€Š58 µm and 210 ±â€Š35 µm, respectively. Compared with the SF/G hybrid scaffold, the SF/G/HA hybrid scaffolds exhibited significantly enhanced compressive strength and modulus. Significant early cell adhesion and proliferation on the SF/G hybrid scaffolds were observed, while SF/G/HA hybrid scaffolds effectively improved osteogenic differentiation of hFOB1.19 after 10 days of coculture. The results confirmed that the 2 hybrid scaffolds were both cytocompatible and had almost no negative effects on the hFOB1.19 in vitro. However, the SF/G/HA hybrid scaffolds tended to be more promising for application in bone-tissue engineering with good mechanical property and osteogenic differentiation.

Comparative study on the incision healing of the palatal mucosa by using Er:YAG laser or traditional scalpel in the SD rats.

The aim of this study was to compare the histology of wound healing following incisions with the scalpel or the Er:YAG laser in the palatal mucosa of SD rats. Two types of wounds were performed with the stainless steel scalpel or the Er:YAG laser in the palatal mucosa of SD rats, while the adjacent untreated palatal mucosa was chosen as control. Rats were sacrificed on day 1, day 3, day 7, and day 30 post-surgery. Biopsy samples from each wound were examined and the expression of IL-1ß and TGF-ß1 was determined by enzyme-linked immunosorbent assay (ELISA). The early postoperative incision of the scalpel group had obvious bleeding and swelling, while the laser wound mainly covered the surface of white pseudomembrane. The infiltration of neutrophils and lymphocytes in the stroma of the scalpel incision was more than that of the laser group. Compared to the laser group, 1 and 3 days after operation, the TGF-ß1 content of the scalpel group were significantly increased (P = 0.032 and 0.019). Seven days after operation, the TGF-ß1 content of two groups was decreased. TGF-ß1 expression of control group was obviously increased (P > 0.05); 1, 3, and 7 days after operation, the traditional scalpel amount of IL-1ß expression was significantly higher than that of control group (P = 0.000, 0.000, and 0.001). Postoperative day 1, IL-1ß expression of laser group and control group had no significant difference (P = 0.572). Three days after operation, IL-1ß expression of laser incision was increased and was significantly higher than that in control group (P = 0.032), however lower than the scalpel group (P = 0.03). Seven days after operation, the IL-1ß expression of two groups had no significant difference (P = 0.333); however, the IL-1ß expression of two groups were significantly higher than that of the control group (P = 0.02 and 0.001). Compared to the traditional scalpel, the incision of Er:YAG laser has smaller inflammation reaction, more pseudomembrane coverage, and minimal damage of the mucoperiosteal tissue.

A Study on Environmental Factors for Nonsyndromic Cleft Lip and/or Palate.

The aim of the study was to investigate the association between environmental factors and nonsyndromic cleft of the lip and/or palate (NSCL/P) in Yantai District, China. A retrospective case-control study was carried out. A total of 236 NSCL/P children were selected from Department of Oral and Maxillofacial Surgery of Yantai Stomatological Hospital between September 2013 and December 2016 as cases; 209 controls were chosen from other diagnosis in the same department during the same period. The 2 groups matched age and sex. The parents of participants were inquired regarding the risk factors, and the answers were filled in a questionnaire by physicians. Chi-square and multivariate logistic regression analysis were used to analysis the data. There was significantly increased NSCL/P risk with high maternal age (P =0.002), family history (P = 0.001), abortion history (P = 0.033), poor parental education level (P = 0.008), maternal smoking (P = 0.044), maternal alcohol (P = 0.039), common cold or fever (P = 0.035), drug use (P = 0.006), and maternal stress (P = 0.049). Reduced NSCL/P risk was found with folic acid supplementation (P = 0.005), adequate maternal age (P = 0.002), and high parental education (P = 0.001). The proper amount of folic acid, the appropriate age of childbearing, and the high education were the protective factors of NSCL/P, whereas family history, abortion history, drug use during pregnancy, maternal tobacco and alcohol, and maternal stress were the risk factors for NSCL/P in Yantai District, China.

[Evaluation of simulated mandibular models in skill training of implantology for dental undergraduates].

PURPOSE: To explore the effects of simulated mandibular models in skill training of implantology for dental undergraduate. METHODS: Pre-clinical teaching of oral implantology was implemented on simulation models for 51 undergraduates of grade 2013. Each undergraduate inserted a dental implant and took an impression in the simulation model under the teacher＇s guidance. After the training course, the scores were evaluated both objectively and subjectively. RESULTS: An average score of 91.6 was obtained in the course of oral implantology on simulated mandibular models. All students appreciated the teaching methods. They believed that training on simulation models could improve their learning interest and arouse their learning motivation. CONCLUSIONS: Simulated mandibular models are good tools in training of oral implantology for dental undergraduates education, which is worthy of wide application.

The synergistic effect of TiO2 nanoporous modification and platelet-rich plasma treatment on titanium-implant stability in ovariectomized rats.

For several decades, titanium and its alloys have been commonly utilized for endosseous implantable materials, because of their good mechanical properties, chemical resistance, and biocompatibility. But associated low bone mass, wear and loss characteristics, and high coefficients of friction have limited their long-term stable performance, especially in certain abnormal bone-metabolism conditions, such as postmenopausal osteoporosis. In this study, we investigated the effects of platelet-rich plasma (PRP) treatment and TiO2 nanoporous modification on the stability of titanium implants in osteoporotic bone. After surface morphology, topographical structure, and chemical changes of implant surface had been detected by scanning electron microscopy (SEM), atomic force microscopy, contact-angle measurement, and X-ray diffraction, we firstly assessed in vivo the effect of PRP treatment on osseointegration of TiO2-modified implants in ovariectomized rats by microcomputed tomography examinations, histology, biomechanical testing, and SEM observation. Meanwhile, the potential molecular mechanism involved in peri-implant osseous enhancement was also determined by quantitative real-time polymerase chain reaction. The results showed that this TiO2-modified surface was able to lead to improve bone implant contact, while PRP treatment was able to increase the implant surrounding bone mass. The synergistic effect of both was able to enhance the terminal force of implants drastically in biomechanical testing. Compared with surface modification, PRP treatment promoted earlier osteogenesis with increased expression of the RUNX2 and COL1 genes and suppressed osteoclastogenesis with increased expression of OPG and decreased levels of RANKL. These promising results show that PRP treatment combined with a TiO2-nanomodified surface can improve titanium-implant biomechanical stability in ovariectomized rats, suggesting a beneficial effect to support the success of implants in osteoporotic bone.

Expression of SKA1 and MMP-9 in primary salivary adenoid cystic carcinoma: Correlation with tumor progression and patient prognosis.

Conclusion The spindle and kinetochore-associated complex sub unit 1(SKA1) and matrix metalloproteinase-9 (MMP-9) are highly expressed in salivary adenoid cystic carcinoma (SACC), and SKA1 may be the novel, promising prognostic factor for clinical outcomes in head and neck adenoid cystic carcinoma patients. Objectives This study aimed to investigate the expression of SKA1 and MMP-9 in SACC tissues and the clinical significance. Methods SKA1 and MMP-9 expression in samples from 42 cases of SACC and 20 subjects with the normal tissue adjacent to carcinoma were detected by immunohistochemical analysis. Results The positive rate of SKA1 and MMP-9 staining was 78.6% and 66.7% in SACC, respectively, significantly higher than in normal salivary gland tissues (p < 0.001). Chi-square test showed that there was no significant correlation between SKA1 expression and MMP-9 expression in SACC tissues. However, SKA1 and MMP-9 expression was positively associated with advanced stage and solid histological pattern of SACC (p < 0.05). In addition, SKA1 and MMP-9 expression was positively associated with recurrence and perineural invasion, and survival time, respectively.

[Malignant ameloblastoma of the jaw: an analysis of 10 consecutive cases.].

PURPOSE: To investigate the clinical and radiographic manifestations of malignant ameloblastoma of the jaw and methods for treatment. METHODS: 10 consecutive cases of malignant ameloblastoma were treated in the Department of Oral and Maxillofacial Surgery, Ninth People's Hospital,Shanghai Second Medical University between 1991 and 2003. All the cases were proved to be malignant ameloblastoma by surgical pathology and followed up for 1 to 8 years. This paper reviewed the clinical manifestation, diagnosis and treatment of these 10 cases. RESULTS: Among the 10 cases of malignant ameloblastoma, 5 were female, 5 were male ,aged from 22 to 60 years. 4 cases were located in the maxilla, and 6 cases in the mandible.All the patients underwent partial mandibulectomy or maxillectomy combined with modified radical neck dissection or supraomohyoid dissection with flap repair at the same time. The follow up outcomes were satisfactory both in appearance and function without recurrence. CONCLUSION: Malignant ameloblastoma is a kind of low degree malignant tumors. Diagnosis is made by pathology. Operation is the only radical method of therapy.