Biomechanical Investigation of the Osseointegration of Titanium Implants With Different Surfaces Placed With Allogeneic Bone Transfer.

Allogeneic grafts can be preferred to autogenous grafts in plastic and oral-maxillofacial surgery for vertical and horizontal bone deficiencies. Implant surface properties are an important factor in osseointegration. This study aims to evaluate the osseointegration levels of titanium implants with machined, sand-blasted, and acid-etched (SLA) and resorbable blast material (RBM) surfaces placed together with allogeneic bone tissue transplantations obtained from the tibia bone using biomechanical method. Twenty-five female Sprague-Dawley rats were included in the study. The rats were divided into groups in which machined (n=7), SLA (n=7), and RBM (n=7) surface implants were placed with the transplantation of bone taken from the tibia. Four rats (both left and right tibias) were used as donors. Grafts and implants were surgically placed in the corticocancellous part of the metaphyseal area of the tibia bones of rats. At the end of the 4-week experimental setup, all rats were killed, and the implants and surrounding bone tissue were subjected to biomechanical reverse torque analysis (N/cm). Sand-blasted acid-etched surface implants were observed to have higher biomechanical osseointegration levels than RBM and machined surface implants (P<0.05). No statistical difference could be detected between the RBM and machined surface implants (P>0.05). On the basis of the limited results of this study, it can be concluded that the osseointegration levels of SLA surface implants placed with allogeneic bone transplantation may be better than those of machined and RBM surface implants.

Evaluation of Liposomal and Microbubbles Mediated Delivery of Doxorubicin in Two-Dimensional (2D) and Three-Dimensional (3D) Models for Breast Cancer.

OBJECTIVE: Liposomal cancer treatment strategies are useful in removing the side effects that were the main concern in recent years. In this study, we prepared microbubble (MBs) conjugated with DOX-loaded liposomes (DOX-loaded MBs) and investigated their effectiveness in in vitro breast cancer cells in two dimensions (2D) and three dimensions (3D). MATERIALS AND METHODS: With this aim, breast cancer cells with different features (4T1, MDA-MB231, MCF-7) were growth in 2D and 3D dimensions. The cytotoxic and cell death effects under different conditions, durations and doses were evaluated with WST-1, trypan-blue, colony counts. Apoptotic effects were investigated with flow cytometric Annexin-V-PI and immunohistochemical (Ki-67, caspase 3, 8, 9) methods. RESULTS: After free DOX and LipoDOX were applied, the proliferation index of three cell lines reduced. Intrinsic and extrinsic apoptotic pathways were activated in both 2D and 3D models. However, this effect was observed at lower levels in the 3D model due to the difficulty of diffusion of DOX into the spheroids. Additionally, the suitability of the 3D model for breast cancer cells was supported by formation of ductus-like structures and spheroids. Cell deaths were not observed significantly with the DOX-loaded microbubbles due to rising of MBs to the surface and not reaching spheroids held in matrigel of 3D model. CONCLUSION: DOX and LipoDOX showed anti-proliferative and apoptosis-inducing effects in breast cancer cells. However, these effects indicated variability depending on the cell lines and 2D or 3D model types.

Cadmium in bone cement induces necrosis and decreases the viability of residual osteosarcoma cells: A xenograft study.

OBJECTIVE: The aim of this study was to show whether local application of cadmium-impregnated bone cement can induce apoptosis and decrease the viability of residual osteosarcoma (OS) cells in nude mice. METHODS: K7M2 tumorigenic OS cell line was cultivated in vitro. The xenograft tumor model was formed by subcutaneously adding the tumor cells to athymic nude mice. Tumor was formed within 1 month. Then, mice were randomly assigned to five groups, each containing seven nude mice: control (group 1), wide resection (group 2), intralesional resection (group 3), intralesional resection + bone cement (group 4), and intralesional resection + cadmium embedded in bone cement (group 5). Tumor resection with 1 cm surgical margins was performed in the wide resection group. In intralesional resection groups, tumor tissue was resected with positive margins aiming to leave 15 mm3 of macroscopic tumor tissue. In group 3, the defect was left empty; groups 4 and 5 received bone cements prepared with saline and cadmium solutions, respectively. After the resection, mice were observed for 15 days and sacrificed. Next, surgical resection sites were evaluated histopathologically in each group. RESULTS: Recurrent tumor was formed in all mice in the wide resection group, and apparent progression of residual tumor was observed in groups 3 and 4. On the contrary, only a thin layer of residual tumor was observed around the bone cement in group 5. Histological evaluation revealed remarkable necrosis in group 5 and lowest viability compared to other groups. No systemic toxic effect related to cadmium was observed. CONCLUSION: Our data suggest that local application of cadmium in bone cement has a significant potential to increase tumor necrosis and decrease the viability of residual OS cells.

The relationship between nurses' work-related variables, colleague solidarity and job motivation.

AIMS: The study was conducted to evaluate the effects of nurses' work-related variables and colleague solidarity on their job motivation. BACKGROUND: The motivation of nurses is an important measure in effective and efficient provision of health care services. METHODS: The sample of this descriptive study included 172 nurses working at a private hospital in Turkey. The Colleague Solidarity Scale for Nurses, Nurses' Job Motivation Scale, and Demographic and Work-Related Variables Questionnaire were used for data collection. Data were analysed using descriptive statistics, Pearson's correlation and backward multiple regression analysis. RESULTS: There was a positive correlation between the scores on the Colleague Solidarity Scale for Nurses and the Nurses' Job Motivation Scale (r: .56, p < .001). Of the nine independent variables evaluated in the multiple regression analysis, five had a significant effect on the job motivation of nurses (R2 : .39, p < .001, Durbin-Watson: 2.12). CONCLUSION: The results of the study show that the three sub-dimensions of the Colleague Solidarity Scale for Nurses, salary and career opportunities were important factors affecting job motivation. IMPLICATIONS FOR NURSING MANAGEMENT: In order to increase nurses' job motivation, nurse managers should work to improve collegial solidarity, create career opportunities and develop salary policies.

Active implant periapical lesions leading to implant failure: two case reports.

Implant periapical lesion (IPL), an inflammatory lesion surrounding the apex of a dental implant, has been previously reported as a possible cause for implant failure. This article describes 2 successive cases of active IPL that were diagnosed early by clinical signs and radiologic findings. Lesions were treated surgically with implant removal and debridement. The etiology, findings, and treatment approaches for IPL are discussed in comparison with other reports.

Periorbital emphysema during dental treatment: a case report.

Periorbital emphysema is a rare complication of dental treatment. To date, there is only 1 case of periorbital emphysema during dental treatment reported in the literature. Etiologies and guidelines for the prevention of this complication during dental treatment were outlined and a rare case was presented.