The favorable biocompatibility of dental biomaterial is very important, which guarantees the safety and effectiveness of its clinical application. The cytotoxicity test, as one of the biological evaluation screening tests, is known to be an important and frequently used method to evaluate biocompatibility of biomaterials. This text is devoted to an overview of the cytotoxicity test for dental materials.
Biocompatible Materials ; toxicity ; Biological Assay ; methods ; trends ; Dental Materials ; toxicity ; Humans ; Materials Testing ; methods

Carbon nanotubes (CNT) are well-ordered, high aspect ratio allotropes of carbon. The two main variants, namely single-walled carbon nanotubes (SWNT) and multi-walled carbon nanotubes (MWNT) both possess the characteristics of high tensile strength, ultra-light weight, and excellent chemical and thermal stability. They also possess the semi- and metallic-conductive properties. This startling array of features has led to many proposed applications in the biomedical field. However, it is only recently that information on toxicity and biocompatibility has become available. Herein is presented a review on the toxicity and biocompatibility of carbon nanotubes.
Animals ; Biocompatible Materials ; toxicity ; Humans ; Materials Testing ; Nanotubes, Carbon ; toxicity ; Toxicity Tests

Cytotoxicity and cytocompatibility remains the principal theme for biomaterials application in medicine. The purpose of this study was to investigate the cytotoxicity and cytocompatibility of collagen/hydroxyapatite(CHA) composite material in vitro in order to provide useful scientific basis for clinical use. Cellular cultivation in vitro and MTT assay were conducted for evaluating the composite material's influence on the morphology, growth and proliferation of cultured cell(L-929 cell). The hemolysis test was also performed for evaluating the impact on the function and metabolism of erythrocyte. These results demonstrated that the CHA composite material had no cytotoxicity and no hemolytic effect, and it might not be harmful to the morphology of the L-929 cell. The growth and proliferation of the L-929 cell could not be inhibited significantly. The cytotoxicity score of the composite material was grade 0. The hemolysis rate was 1.85%. In conclusion, collagen/hydroxyapatite (CHA) composite material might have good cytocompatibility and be safe for clinical use.
Animals ; Biocompatible Materials ; toxicity ; Cells, Cultured ; Collagen ; toxicity ; Hydroxyapatites ; toxicity ; Mice ; Prostheses and Implants ; Toxicity Tests ; Trachea

Nowadays, nanotechnologies have shown wide application foreground in the biomedical field of medicine laboratory tests, drug delivery, gene therapy and bioremediation. However, in recent years, nanomaterials have been labeled poisonous, because of the disputes and misunderstandings of mainstream views on their safety. Besides, for the barriers of technical issues in preparation like: (1) low efficacy (poor PK & PD and low drug loading), (2) high cost (irreproducibility and difficulty in scale up), little of that research has been successfully translated into commercial products. Currently, along with the new theory of "physical damage is the origin of nanotoxicity", biodegradability and biocompatibility of nanomaterials are listed as the basic principle of safe application of nanomaterials. Combining scientific design based on molecular level with precision control of process engineering will provide a new strategy to overcome the core technical challenges. New turning point of translational medicine in nanotechnology may emerge.
Biocompatible Materials ; Nanostructures ; toxicity ; Nanotechnology ; Translational Medical Research

In this study, heparin ionically coated polyvinyl chloride (PVC) material was prepared by heparin-benzalkonium chloride complex (Group A), heparin-benzalkonium bromide complex (Group B) and heparin-polyethyleneimine compound (Group C). Cytotoxicity evaluation was conducted by direct cell contact evaluation and MTT colorimetry method. The results showed Group A and Group B caused L-929 cells to die out while Group C showed good compatibility with cells. The OD levels of Group A and B were lower than that of the Group C in MTT test. Method A and method B of heparin coating had remarkable cytotoxicity, while method C had little cytotoxicity and could be further studied for clinical use.
Animals ; Cells, Cultured ; Coated Materials, Biocompatible ; toxicity ; Fibroblasts ; cytology ; Heparin ; toxicity ; Materials Testing ; Mice ; Polyvinyl Chloride ; toxicity

This assay was aimed to evaluate the influence of different contact ways and extracting conditions on the hemolytic effect of biomaterials. Using direct contact method and extract contact method, we assessed the hemolytic effect of PDLLA and PVC. The extracting conditions included: 37 degrees C 24 h, 37 degrees C 72 h, 37 degrees C 120 h, 50 degrees C 72 h, and 70 degrees C 24 h. After the material or extract had been in contact with the diluted blood of rabbit for certain times, the hemolysis rate was calculated. The results for PDLLA showed there were some differences between direct contact and extract contact at 37 degrees C for different extraction time (P < 0.05), but the hemolysis rates, lower than 5%, were in accord with the requirements of medical devices. However, under the condition of 50 degrees C and 70 degrees C, there were significant differences when extract contact method was compared with direct method (P < 0.01). For PVC, there was no statistically significant difference under all conditions (P > 0.05). Our conclusions: (1) Under the extracting condition of 37 degrees C from 24 h to 120 h, the soluble part of PDLLA and PVC that might influence erythrocyte did not dissolve considerably. (2) Under the extracting condition of 50 degrees C and 70 degrees C, the hemolysis rate may remarkably vary with the chemical characteristics of tested materials; (3) As to an unknown material, it is advisable to adopt two methods at the same time, one for direct contact and the other for extracontact. Thus the hemolytic effect of biomaterials can be evaluated from physical and chemical angles. (4) In case that the chemical property of the sample can endure the test, the extracting condition at 50 degrees C and 70 degrees C may be of benefit to assessing the hemolytic effect of biomaterials. (5) The extract contact method as a supplemental test of direct contact method is of realistic significance.
Animals ; Biocompatible Materials ; toxicity ; Hydrolysis ; drug effects ; In Vitro Techniques ; Materials Testing ; methods ; Rabbits ; Temperature ; Time Factors

The immunoreaction caused by biomaterials or medical devices are even more concerned by people. It is necessary to establish the immune items in the biological evaluation of biomaterials and medical devices. And it is a tendency to use immune technique combined with molecular biological methods to evaluate the immunoreaction for biomaterials.
Biocompatible Materials ; adverse effects ; Equipment and Supplies ; adverse effects ; Immunity ; Materials Testing ; methods ; Toxicity Tests

The evaluation of biomaterial effectiveness and safety is a key step before the biomaterial approaches to clinics. In recent years, lots of new biomaterials with different composition, shape, implant site and use have been coming out and in need of more special, sensitive and systematic evaluation methods. With the development of immunology, microdetective technique, inbred strain mammal and other connective branches, there are many chances for the consummation and integration of biomaterial evaluation system. The three-"R" principle (replace, refine, reduce), that is, developing in vitro experiments, using sensitive, special and advanced evaluation methods, improving and reducing the member of experimental animals, as well as the fundamental rule, that is, establishing an evaluation system covering three levels (molecule, cell and body) will guide the research of biomaterial evaluation to more promising development.
Animals ; Biocompatible Materials ; toxicity ; Equipment Safety ; In Vitro Techniques ; Materials Testing ; Swine

OBJECTIVEThe micronucleus test was applied to evaluate the genotoxicity of a new nanocomplex HA-PA66 root filling material in vitro.

METHODSThe dulbecco's modified eagle media(DMEM) extracts of the powder part and the mixture of the new nanomaterial were prepared separately. The V79 cell was used as the test cell and the mitomycin C(MMC) as the positive control. The MTT assay was employed in our study to evaluate the cytotoxic effect while the number of micronucleus was used as the criteria for the detection of genotoxocity.

RESULTSThe MTT values in test groups and negative group were not significantly different at different times (P > 0.05). The number of micronucleus in test groups (powder group: 6.1 +/- 1.1/1,000; complex group: 5.7 +/- 0.6/1,000) was similar to the negative control(5.3 +/- 0.8/1,000, P > 0.05), while they were significantly different to the positive control(123.9 +/- 8/1,000, P < 0.05).

CONCLUSIONThe new nanocomplex HA-PA66 root filling material showed no detectable cytotoxic and genotoxic effects in this study and was proved to be biocompatible.

Animals ; Biocompatible Materials ; toxicity ; Cricetinae ; Cricetulus ; Durapatite ; toxicity ; Micronucleus Tests ; methods ; Mutagenicity Tests ; methods ; Nanotechnology ; Nylons ; toxicity ; Root Canal Filling Materials ; toxicity

In this paper, an immunosuppression model of immunotoxicity built through applying immunosuppressive agent-cyclophosphamide. Subsequently the changes of some assessment indexes including total amount of lymphocytes and concentration of cytokine TNF-alpha in peripheral blood were observed and were used to evaluate immunotoxicity induced by Medical Heat Vulcanizing Silicone Rubber. The final results showed no immunosuppressive effect caused by this material. The study provide effective and sensitive detection technique for evaluation of medical devices and biomaterials' immunotoxicity.
Animals ; Biocompatible Materials ; toxicity ; Elastomers ; toxicity ; Female ; Immunosuppressive Agents ; Lymphocytes ; immunology ; Male ; Materials Testing ; Mice ; Rubber ; toxicity ; Silicones ; toxicity ; Tumor Necrosis Factor-alpha ; blood