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To compare the stress distribution of dental implants with different body shapes after maxillary sinus augmentation.Three different implant models varying in implant shape were investigated in D3-type maxilla. All materials were assumed to be linear elastic, homogenous and isotropic. An oblique force of 150 N was applied to the implant. Maximal equivalent von-Mises of supporting bone around implants were measured. All of the models were measured by Ansys Workbench 14.5. Statistical analysis was performed using SPSS 17.0 software package.Highest stress of supporting bone emerged on the crestal cortical site around the implant neck. There was no significant difference in the maximum EQV of supporting cortical bone between different groups; the maximum EQV of supporting trabecular bone in the tapered implant group was much higher than other groups; application of grafts reduced the maximum EQV of both cortical and trabecular bone in all groups.Tampered implant can induce elevated stress distribution of the upper trabecular bone, which may promote marginal bone loss. Application of grafts after maxillary sinus augmentation could favors in reducing the stress loading of dental implants.

The purpose of this study was to investigate the efficacy of microvascular coupler for arterial anastomosis in head and neck reconstruction during a 2-year period at the Department of Oral and Maxillofacial Surgery, Shandong Provincial Hospital.Twenty-one cases of microvascular free flaps from October 2013 through December 2014 were retrospectively reviewed. Flap survival and thrombosis of the arterial anastomoses were determined in these cases.A total of 21 consecutive patients underwent microsurgical head and neck reconstruction, including 7(33.33%) radial forearm, nine(42.86%) fibular and 5(23.81%) anterior lateral thigh free flaps. There was 1 complication related to arterial thrombosis in this series, requiring surgical reexploration and a sutured anastomosis was performed. There were no complications related to technical performance of the coupling device.Use of a coupler device shows reliability for arterial anastomosis in head and neck reconstruction. With proper vessel selection and sufficient experience using the microvascular coupler, arterial coupling may be performed in an expeditious, safe, and reliable fashion with minimal morbidity. Though not commonly practiced, use of coupling device for arterial anastomosis can significantly save time, which is a viable alternative to sutured anastomosis.

To investigate the effect of NaF on proliferation and mineralization of human periodontal ligament cells (hPDLCs).hPDLCs were isolated and characterized. The proliferation of hPDLCs treated with different concentration of NaF was tested by CCK-8. Four moderate concentrations were chosen for subsequent experiments. The mineralization was investigated using ALP activity assay, Alizarin red S staining and quantitative real-time polymerase chain reaction(RT-PCR). The data were statistically analyzed with SPSS20.0 software package.Immunohistochemistry showed that the isolated cells were hPDLCs. 5×105×10

To study the influence of nodal liquefaction portion in the measurement of the ADC value of metastatic lymph nodes in patients with oral squamous cell carcinoma (OSCC) on DW-MRI images.According to the postoperative histopathological examination results, the DW-MRI data of 25 OSCC patients was analyzed. The ADC values of both solid portions of metastatic lymph nodes and the whole metastatic lymph nodes with internal liquefaction were selected and measured. Further comparison between the 2 groups was processed for 2 independent samples t test with SPSS 17.0 software package.Eleven patients out of all cases were diagnosed with cervical lymph node metastasis, and 15 metastatic lymph nodes were detected, among which 8 metastatic lymph nodes had obvious internal liquefaction. The average ADC values of solid portions of metastatic lymph nodes (group SMLN) and the whole metastatic lymph nodes with internal liquefaction (LMLN group) ADC were (872.1 ± 22.65) × 10⁻⁶ mm²/s (n=15) and (1073 ± 16.99) × 10⁻⁶ mm²/s (n=8), respectively. Two independent samples t test showed statistically significant difference of ADC values between group SMLN and group LMLN (P0.05).The internal liquefaction in OSCC metastatic lymph nodes can lead to an increased average ADC value. If the measurement of OSCC metastatic lymph nodes includes obvious liquefaction portions, it may reduce the diagnostic accuracy of DW-MRI for discrimination of lymph node metastasis.

To investigate the expression of p53 and Beclin1 in salivary pleomorphic adenoma (PA) and its clinical significance.The expression of p53 and Beclin1 were assessed by immunohistochemistry in 108 cases of PA and 20 cases of carcinoma in pleomorphic adenoma(CIPA). The results were used to analyze the relationship between gene expressions and the development of PA as well as the clinical pathological features. Statistic analysis was conducted with SPSS 20.0 software package.The positive expressions of p53 in PA samples (9%) were significantly lower than that in CIPA(14%) (P0.001). The positive expressions of autophagy-related gene Beclin1 in PA samples(91%) were significantly higher than that CIPA (11%) (P0.001). The expression levels of these genes were not associated with gender, age, clinical course, tumor size, and location of PA(P0.05). There was a negative correlation between p53 and Beclin1 expression in PA (r=-0.330,P0.05).The expression levels of Beclin1 and p53 protein are closely related to the development of PA. Reduced autophagy and enhanced anti apoptosis coexist in the process of tumor formation. Thus, raising the autophagy ability may become another alternative choice for cancer therapy.

To detect the expression of p65, a subunit of NF-κB proteins, and apoptosis after adenoid cystic carcinoma cells(ACC-2) irradiated by high energy X-ray, and to investigate the interaction between them.ACC-2 cells were cultured and then irradiated by high energy X-ray of different dose(2, 4, 6, 8,10Gy). At the next six time points(1, 3, 6, 10, 24, 48h), the expression of p65 protein in cytoplasm and nucleus was detected by immunocytochemistry and Western blotting. The apoptotic cells were counted by flow cytometry and then observed by TUNEL technique. The data of radiant intensity and apoptotic rate were statistically analyzed by Spearman method with SPSS11.5 software package.In ordinary condition, p65 protein seldom appeared in the nucleus, and mostly stained in the cytoplasm by immunocytochemistry. After irradiation, the protein was observed around the nuclear. Then it went through the nuclear membrane more and more as time going on, finally to the center of the nucleus. The quantity of p65 among the total protein changed gradually after radiation, rising at first, which got to a peak after about 6 to 10 hours, according to the results of Western blotting. At the same time point, p65 protein was found to have a higher expression with a higher dose of irradiation correspondingly. The proportion of apoptotic cells also varied from time to time, and an obvious valley of the apoptotic curve was at the 10th hour after radiation. Compared with the outcome of Western blotting, the results indicated a negative correlation between the apoptotic rate and the radiant intensity or p65 protein expression(P0.05).The expression of p65 protein is affected by the irradiation of p65 of high energy X-ray, which is dose-time dependent. The proportion of apoptotic cells decreases as the expression increases.

To investigate the radiosensitization by prodrug and CD-TK double suicide gene therapy system in adenoid cystic carcinoma cells (ACC-2).The eukaryotic expression plasmids pIRES-CD and pIRES-TK were introduced into ACC-2 cells by electroporation. Then ACC-2 cells stably expressing CD and TK gene were obtained by 10-day positive selection with 400 micro g/mL G418 . The total RNA was extracted and the expression of the CD and TK gene in transfected ACC-2 cells was identified by RT-PCR. The positive transfected ACC-2 cells were treated with radiotherapy of different dose (0,2,4,6,8,10 Gy) and prodrug system in aerobic and anoxic condition. Then cell clone formation assay was used to study the radiosensitization by CD-TK double suicide gene therapy and prodrug system in ACC-2.The data was analyzed by multiple factor ANOVA using SPSS11.5 software package.RT-PCR analysis demonstrated that CD and TK genes were effectively expressed in ACC-2 cells. With the increased of X-ray dose, the colony forming rate dropped significantly after radiotherapy. In aerobic condition, the survival fraction of group ACC-2/CD-TK+prodrug were significantly lower than that of group ACC-2 and group ACC-2/CD-TK with the same dose (P0.05). In anoxic condition, the survival fraction of group ACC-2/CD-TK+pro-drug was significantly lower than that of experimental group ACC-2 and group ACC-2/CD-TK with the same dose (P0.05). The colony forming rate in aerobic condition was significantly lower than that in anoxic condition of the same cell group and dose.The radiosensitivity and the killing effect of X ray to ACC-2 cells can be increased by CD-TK double suicide gene therapy and the prodrug system.

To clone CD gene, construct its eukaryotic expression vector pIRES-CD and obtain positive ACC-2 cells expressing E.coli CD gene stably.PCR amplification was performed using primers based on E.coli CD gene sequence from Genebank, E.coli genomic DNA as template. PCR product was inserted into pMD18-T. After sequence confirmation, the gene was subcloned to pIRES to construct recombinant eukaryotic expression vector pIRES-CD. Then the combinant plasmid was conducted into ACC-2 cell by electroporation. ACC-2 cells stably expressing CD was obtained by 10-day positive selection with 400 mug/mL G418. Total RNA was extracted and the expression of the CD gene in transfected ACC-2 cells was identified by RT-PCR.PCR yielded a fragment of 1280bp and CD was verified by sequence analysis. A fragment of 6.1kb and inserted fragment of 1280bp were obtained by cutting positive recombinant plasmid of pIRES-CD with XbaI and NotI. RT-PCR analysis demonstrated that CD gene could be effectively expressed in ACC-2 cells.The CD gene is successfully amplified and the eukaryotic expression plasmid containing E.coli CD is successfully constructed.The positive ACC-2 cell clones expressing CD gene stably are obtained, which provide a basis for further study of adenoid cystic carcinoma gene therapy with CD/5-FC suicide gene system. Supported by Natural Science Foundation of Shandong Province(Grant No.Z2003C03).

To evaluate the recovery of infraorbital nerve injury after middle facial fracture.28 patients with infraorbital nerve injury were examined in l month, 3 months, 6 months and 12 months after operation by using sharp-blunt test, two-point discrimination,electric pain response test. The data were analyzed with SPSS12.0 software package for Student's t test.25 cases (25 of 28) with injured nerve recovered normally.The average time of recovery was 25 weeks. The injured nerve didnot recover in 3 of 28. No chronic neuropathic pain was found.Most nerve dysfunctions following middle facial fracture are reversible and temporary,very few are permanent. If the injured nerve doesn't recover within 6 months, infraorbital nerve decompression may be selected to promote the recovery of the nerve function.

To investigate the diagnosis and therapeutic approaches of carotid body tumor (CBT).In this study, the medical records of 19 patients with carotid body tumor were reviewed retrospectively. These patients had been referred to the Department of Oral and Maxillofacial Surgery in Shandong Provincial Hospital from 1999 to 2004.B ultrasound, DSA, MRI, CTA were used as the modalities of diagnosis for 19 CBT cases. All patients were submitted to surgical resection of the tumor. Among them, preoperative Matas test was carried out in 7 patients. Monitoring retrograde stump pressure of internal carotid artery was performed in all the cases during the operations. 11 patients underwent TCD examination before and during operation. Internal shunt was applied in 5 cases. Postoperatively, paralysis of hypoglossal never occurred in 4 patients, paralysis of pneumogastric never occurred in one patient, no hemiplegia and death occurred.DSA CTA, MRI are more effective modalities to diagnose CBT. The way of choosing local anaesthesia firstly and then general anaesthesia is preferable. Monitoring of TCD, retrograde stump pressure of internal carotid artery and internal shunt application are the keys for successful Surgery.

The purpose of this study was to investigate the occurrence of p53 gene mutation in salivary adenoid cystic carcinoma, the correlation between the gene and prognostic significance.A series of salivary adenoid cystic carcinoma were studied by polymerase chain reaction and single strand conformation polymorphism (PCR-SSCP) analysis to detect p53 mutation, respectively.The result showed that p53 gene mutations in exon 5-8 were detected in 65.8% (25/38) of the salivary adenoid cystic carcinoma. The p53 gene mutation was related to tumor distant metastasis and tumor recurrence (P0.05) but not related to pathological types, clinical stages (P0.05).There was a significant correlation between p53 gene mutation and postoperative survival .It is suggested that p53 gene mutations were very common in salivary adenoid cystic carcinoma, and might be useful in screening progress and evaluating prognosis of patients.