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Int. j. morphol ; 35(4): 1203-1208, Dec. 2017. graf
Article in English | LILACS | ID: biblio-893115


SUMMARY: Biomaterials are mostly polymers and are used in artificial organ production in contemporary medicine. They are prepared by the polymerization reaction of many monomers. There are many monomers used in biomaterial production. In this study, we investigated whether acrylamide (AAm), methacrylamide (MAAm), N-isopropylacrylamide (NIPAm) and acrylic acid (AAc) used in polymeric biomaterial production had histopathological effects on renal tissue. In the present study, Wistar albino rats weighing ~ 250-300 g were used. Following the intramuscular injections of 1 mL aqueous monomer solutions at 50 mg/kg concentrations, acrylamide group animals were sacrificed at 1st, 2nd and 3rd weeks, the other monomer group animals were sacrificed at 1st, 2nd, 4th and 6th weeks. One mL serum physiologic were injected intramuscularly to the control group animals at the same time intervals with the experimental group animals. After histological follow-up, serial sections were prepared for evaluation under light microscope. In addition, the diameters of glomeruli and glomeruli space (Bowman's space) are measured, and the changes of the values of all groups with the exposure time were investigated. Acrylamide and its derivatives cause glomerular, arteriolar and tubule interstitial damage in the renal tissue. The narrowing glomeruli space, increasing diffuse mesangial matrix and tubular dilation was observed in some groups. In addition, dilatation, dissociation of tubular epithelium, thickening basement membranes and glycogenic vacuolization was also noted. These adverse results may be due to residual monomer. There should be no monomer residue in the polymer used as biomaterials.

RESUMEN: Los biomateriales en su mayoría son polímeros utilizados en la producción de órganos artificiales en la medicina contemporánea. Éstos son preparados mediante la reacción de polimerización de varios monómeros. Existe una gran cantidad de monómeros usados en la producción de biomateriales. En este estudio se investigó si la acrilamida (AAm), la metacrilamida (MAAm), la N-isopropilacrilamida (NIPAm) y el ácido acrílico (AAc) utilizados en la producción de biomateriales poliméricos tuvieron efectos histopatológicos en el tejido renal. En el presente estudio, se utilizaron ratas Wistar albinas que pesaban 250-300 g. Después de las inyecciones intramusculares (1 ml) de soluciones acuosas de monómero a concentraciones de 50 mg / kg, los animales del grupo de la acrilamida se sacrificaron a la 1ª, 2ª y 3ª semanas, los otros animales del grupo monómero se sacrificaron a las 1ª, 2ª, 4ª y 6ª semanas. Se inyectaron intramuscularmente 1 ml de suero fisiológico a los animales del grupo control en los mismos intervalos de tiempo que los animales del grupo experimental. Después del análisis histológico, se prepararon secciones en serie para su evaluación bajo microscopio óptico. Además, se midieron los diámetros de los glomérulos y el espacio glomerular, y se investigaron los cambios de los valores de todos los grupos con el tiempo de exposición. La acrilamida y sus derivados causaron daño intersticial glomerular, arteriolar y tubular en el tejido renal. El estrechamiento del espacio de los glomérulos, el aumento de la matriz mesangial difusa y la dilatación tubular se observó en algunos grupos. Además, también se observó dilatación, disociación del epitelio tubular, membranas basales espesantes y vacuolización glicogénica. Estos resultados adversos pueden deberse al monómero residual. No debe haber residuo de monómero en el polímero utilizado como biomateriales.

Animals , Rats , Acrylamide/toxicity , Kidney/pathology , Acrylates/toxicity , Biocompatible Materials/toxicity , Immunohistochemistry , In Situ Nick-End Labeling , Kidney/drug effects , Polymers , Rats, Wistar
Braz. oral res. (Online) ; 30(1): e48, 2016. tab, graf
Article in English | LILACS | ID: biblio-952020


Abstract Several calcium silicate-based biomaterials have been developed in recent years, in addition to Mineral Trioxide Aggregate (MTA). The aim of this study was to evaluate the cytotoxicity, genotoxicity and apoptosis/necrosis in human osteoblast cells (SAOS-2) of pure calcium silicate-based cements (CSC) and modified formulations: modified calcium silicate-based cements (CSCM) and three resin-based calcium silicate cements (CSCR1) (CSCR 2) (CSCR3). The following tests were performed after 24 hours of cement extract exposure: methyl-thiazolyl tetrazolium (MTT), apoptosis/necrosis assay and comet assay. The negative control (CT-) was performed with untreated cells, and the positive control (CT+) used hydrogen peroxide. The data for MTT and apoptosis were submitted to analysis of variance and Bonferroni's posttest (p < 0.05), and the data for the comet assay analysis, to the Kruskal-Wallis and Dunn tests (p < 0.05). The MTT test showed no significant difference among the materials in 2 mg/mL and 10 mg/mL concentrations. CSCR3 showed lower cell viability at 10 mg/mL. Only CSC showed lower cell viability at 50 mg/mL. CSCR1, CSCR2 and CSCR3 showed a higher percentage of initial apoptosis than the control in the apoptosis test, after 24 hours exposure. The same cements showed no genotoxicity in the concentration of 2 mg/mL, with the comet assay. CSC and CSCR2 were also not genotoxic at 10 mg/mL. All experimental materials showed viability with MTT. CSC and CSCR2 presented a better response to apoptosis and genotoxicity evaluation in the 10 mg/mL concentration, and demonstrated a considerable potential for use as reparative materials.

Humans , Osteoblasts/drug effects , Silicates/toxicity , Calcium Compounds/toxicity , Dental Cements/toxicity , Oxides/toxicity , Tetrazolium Salts , Biocompatible Materials/toxicity , Materials Testing , Cell Survival/drug effects , Cells, Cultured , Reproducibility of Results , Analysis of Variance , Apoptosis/drug effects , Aluminum Compounds/toxicity , Comet Assay , Cell Proliferation/drug effects , Drug Combinations , Formazans , Necrosis/chemically induced
J. appl. oral sci ; 22(6): 554-559, Nov-Dec/2014. tab, graf
Article in English | LILACS, BBO | ID: lil-732588


Objective Mineral Trioxide Aggregate (MTA) is composed of Portland Cement (PC) and bismuth oxide (BO). Replacing BO for niobium oxide (NbO) microparticles (Nbµ) or nanoparticles (Nbη) may improve radiopacity and bioactivity. The aim of this study was to evaluate the radiopacity and cytotoxicity of the materials: 1) PC; 2) White MTA; 3) PC+30% Nbµ; 4) PC+30% Nbη. Material and Methods For the radiopacity test, specimens of the different materials were radiographed along an aluminum step-wedge. For cell culture assays, Saos-2 osteoblastic-cells (ATCC HTB-85) were used. Cell viability was evaluated through MTT assay, and bioactivity was assessed by alkaline phosphatase activity assay. Results The results demonstrated higher radiopacity for MTA, followed by Nbµ and Nbη, which had similar values. Cell culture analysis showed that PC and PC+NbO associations promoted greater cell viability than MTA. Conclusions It was concluded that the combination of PC+NbO is a potential alternative for composition of MTA. .

Humans , Aluminum Compounds/toxicity , Calcium Compounds/toxicity , Dental Cements/toxicity , Nanoparticles/toxicity , Niobium/toxicity , Oxides/toxicity , Silicates/toxicity , Aluminum Compounds/chemistry , Analysis of Variance , Biocompatible Materials/chemistry , Biocompatible Materials/toxicity , Calcium Compounds/chemistry , Cell Survival , Cells, Cultured , Dental Cements/chemistry , Drug Combinations , Formazans , Materials Testing , Nanoparticles/chemistry , Niobium/chemistry , Osteoblasts/drug effects , Oxides/chemistry , Silicates/chemistry , Statistics, Nonparametric , Tetrazolium Salts , Time Factors
J. appl. oral sci ; 21(4): 351-357, Jul-Aug/2013. graf
Article in English | LILACS | ID: lil-684567


OBJECTIVE: The aim of this study was to compare the cytotoxic effects of endodontic cements on human tooth germ stem cells (hTGSCs). MTA Fillapex, a mineral trioxide aggregate (MTA)-based, salicylate resin containing root canal sealer, was compared with iRoot SP, a bioceramic sealer, and AH Plus Jet, an epoxy resin-based root canal sealer. MATERIAL AND METHODS: To evaluate cytotoxicity, all materials were packed into Teflon rings (4 mmµ3 mm) and co-cultured with hTGSCs with the aid of 24-well Transwell permeable supports, which had a pore size of 0.4 µm. Coverslips were coated with MTA Fillapex, iRoot SP and AH Plus Jet and each coverslip was placed onto the bottom of one well of a six-well plate for scanning electron microscopy (SEM) analysis. Before the cytotoxicity and SEM analysis, all samples were stored at 37ºC and at 95% humidity and 5% CO2 for 24 hours to set. The cellular viability was analyzed using MTS test (3-(4,5-dimethyl-thiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium). The cytotoxic effects and SEM visualization of the tested materials were analyzed at 24-hour, 72-hour, one-week and two-week periods. RESULTS: On the 1st day, only MTA Fillapex caused cytotoxicity compared to negative control (NC) group (p<0.008). No significant difference was observed between the other tested materials at this period (p>0.05). After 14 days of incubation with the test materials, MTA Fillapex exhibited significantly higher cytotoxicity compared with iRoot SP, AH Plus Jet and the NC group (P<0.008). In the SEM analysis, the highest levels of cell attachment were observed for iRoot SP and the control group. After 24 hours, MTA Fillapex reduced the number of cells attached to the surface. CONCLUSIONS: Within the limitations of this study, sealers exerted different cytotoxic effects on hTGSCs. Although all materials ...

Humans , Calcium Compounds/toxicity , Dental Cements/toxicity , Silicates/toxicity , Stem Cells/drug effects , Tooth Germ/cytology , Aluminum Compounds/toxicity , Biocompatible Materials/toxicity , Cells, Cultured , Cell Survival/drug effects , Drug Combinations , Epoxy Resins/toxicity , Materials Testing , Microscopy, Electron, Scanning , Oxides/toxicity , Root Canal Filling Materials/toxicity , Statistics, Nonparametric , Surface Properties/drug effects , Time Factors
Arq. bras. oftalmol ; 76(3): 141-146, maio-jun. 2013. ilus, graf
Article in Portuguese | LILACS | ID: lil-681844


OBJETIVO:Avaliar a biocompatibilidade de material FullCure 720®, que é uma resina, na confecção de implante orbitário. Avaliou-se a resposta clínica dos animais, toxicidade sistêmica e a resposta inflamatória crônica. Os animais foram pesados, exames bioquímicos e resposta inflamatória foram avaliados. Foi efetuada evisceração e colocado implante esférico orbitário. Os animais foram acompanhados durante o período de 60 dias, onde se avaliou o comportamento clínico e sinais locais. Após este período, procedeu-se a eutanásia seguida da enucleação. Foi realizada análise macroscópica e histomorfométrica. Os resultados revelaram comportamento normal dos animais, com ausência de exposição ou extrusão dos implantes, morte de algum animal e ausência de toxicidade sistêmica. Houve formação de uma cápsula fibrosa entre a capa escleral e o implante orbitário, resposta inflamatória considerada normal quando em contato com o tecido do coelho. A resina FullCure 720® utilizada como implante orbitário, mostrou-se biocompatível neste estudo.

PURPOSE: To evaluate the resin FullCure 720® biocompatibility as orbital implant. Clinical response and signs of systemic toxicity to the resin were evaluated, local biocompatibility and microscopic analysis regarding chronic local inflammatory response to the implant. The animals were weighted, biochemical exams and inflammatory response were evaluated. All animals were eviscerated and implantation of the spheres was carried out. Animals were followed for 60 days. Clinical behavior of animals and local signals of inflammation had been observed. After this period animals underwent euthanasia followed by enucleation. Macroscopic and histomorphometric analysis were performed. The results showed normal behavior of the animals, without implant exposure, extrusion, death or systemic toxicity. Capsule tissue formation was observed between the sclera and the implant. Normal inflammatory response to the foreign material in contact with the rabbit soft tissue was observed. The resin FullCure 720®, demonstrated to be biocompatible as an orbital implant in this study.

Animals , Male , Rabbits , Acrylic Resins/toxicity , Biocompatible Materials/toxicity , Materials Testing , Orbital Implants , Acrylic Resins/therapeutic use , Models, Animal , Prosthesis Implantation/methods , Reproducibility of Results , Surface Properties , Sclera/drug effects , Time Factors
J. appl. oral sci ; 21(1): 37-42, 2013. ilus, graf
Article in English | LILACS, BBO | ID: lil-684993


Objective: The aim of this study was to produce dense granules of tricalcium phosphate (β-TCP) and magnesium (Mg) substituted β-TCP, also known as β-TCMP (Mg/Ca=0.15 mol), in order to evaluate the impact of Mg incorporation on the physicochemical parameters and in vitro biocompatibility of this novel material. Material and Methods: The materials were characterized using X-ray diffraction (XRD), infrared spectroscopy (FTIR), electron microscopy and inductively coupled plasma (ICP). Biocompatibility was assayed according to ISO 10993-12:2007 and 7405:2008, by two different tests of cell survival and integrity (XTT and CVDE). Results: The XRD profile presented the main peaks of β-TCP (JCPDS 090169) and β-TCMP (JCPDS 130404). The characteristic absorption bands of TCP were also identified by FTIR. The ICP results of β-TCMP granules extract showed a precipitation of calcium and release of Mg into the culture medium. Regarding the cytotoxicity assays, β-TCMP dense granules did not significantly affect the mitochondrial activity and relative cell density in relation to β-TCP dense granules, despite the release of Mg from granules into the cell culture medium. Conclusion: β-TCMP granules were successfully produced and were able to release Mg into media without cytotoxicity, indicating the suitability of this promising material for further biological studies on its adequacy for bone therapy.

Biocompatible Materials/toxicity , Calcium Phosphates/toxicity , Magnesium/toxicity , Analysis of Variance , Biocompatible Materials/pharmacokinetics , Bone Substitutes/pharmacokinetics , Bone Substitutes/toxicity , Calcium Phosphates/pharmacokinetics , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured/drug effects , Materials Testing , Microscopy, Electron, Scanning , Magnesium/pharmacokinetics , Osteoblasts/drug effects , Spectrum Analysis , Time Factors , Toxicity Tests , X-Ray Diffraction
J. appl. oral sci ; 21(1): 43-47, 2013. tab, graf
Article in English | LILACS, BBO | ID: lil-684994


Objectives: The aim of the present study was to investigate the effects of root canal sealers on the cytotoxicity of 3T3 fibroblasts during a period of 5 weeks. Material and Methods: Fibroblasts (3T3, 1×105 cells per well) were incubated with elutes of fresh specimens from eight root canal sealers (AH Plus, Epiphany, Endomethasone N, EndoREZ, MTA Fillapex, Pulp Canal Sealer EWT, RoekoSeal and Sealapex) and with elutes of the same specimens for 5 succeeding weeks after immersing in simulated body fluid. The cytotoxicity of all root canal sealers was determined using the MTT assay. Data were analyzed using ANOVA and Tukey's test. Results: RoekoSeal was the only sealer that did not show any cytotoxic effects (p<0.05). All the other tested sealers exhibited severe toxicity initially (week 0). MTA Fillapex remained moderately cytotoxic after the end of experimental period. Toxicity of the other tested sealers decreased gradually over time. The evaluated root canal sealers presented varying degrees of cytotoxicity, mainly in fresh mode.Conclusions: RoekoSeal had no cytotoxic effect both freshly mixed and in the other tested time points. MTA Fillapex was associated with significantly less cell viability when compared to the other tested root canal sealers.

Animals , Mice , /drug effects , Root Canal Filling Materials/toxicity , Biocompatible Materials/toxicity , Calcium Hydroxide/toxicity , Cell Survival/drug effects , Composite Resins/toxicity , Drug Combinations , Dental Cements/toxicity , Dexamethasone/toxicity , Epoxy Resins/toxicity , Formaldehyde/toxicity , Hydrocortisone/toxicity , Salicylates/toxicity , Time Factors , Thymol/analogs & derivatives , Thymol/toxicity
Braz. j. oral sci ; 9(3): 366-370, July-Sept. 2010. ilus, tab
Article in English | LILACS, BBO | ID: lil-578057


Aim: To test the hypothesis that there is no difference in the cytotoxicity among natural latex elastics of different manufacturers using a L929 cell line culture. Methods: Different latex intra oral elastics (I.D. = 5/16", 4.5 oz.) were tested. The sample was divided into 7 groups of 15 elastic seach: Group AO (American Orthodontics), Group GAC (GAC International), Group TP (TP Orthodontics), Group AD (Aditek), Group AB (Abzil), Group MO (Morelli) and Group UN (Uniden).Cytotoxicity assays were performed by using cell culture medium containing L-929 line cells(mouse fibroblast). The cytotoxicity was evaluated by using the “dye-uptake” test, which wasemployed at two different moments (1 and 24 h). Data were compared by ANOVA and Tukey’s test(P < 0.05). Results: The results showed a significant difference (P < 0.05) between all groups and the group CC (cell control) at 1 and 24 h. Groups AD, AB, MO and UN were noticeably more cytotoxic than the groups AO, GAC and TP at 1 h. After 24 h, a significant decrease in cell viability was observed in all groups. Conclusions: Intraoral elastics from American Orthodontics, GACand TP Orthodontics trademarks induced less cell lysis than Aditek, Abzil, Morelli and Uniden trademarks.

Dental Materials/toxicity , Latex/toxicity , Orthodontic Appliances , Analysis of Variance , Biocompatible Materials/toxicity , Cells, Cultured , Fibroblasts/metabolism , Materials Testing , Time Factors
Int. j. odontostomatol. (Print) ; 4(1): 81-85, abr. 2010. ilus, tab
Article in English | LILACS | ID: lil-596808


Natural latex does not fall into the category of materials known to be entirely inoffensive. The objective of the present in vitro study is to test the hypothesis that there is no difference in the cytotoxicity between natural latex elastics of different colours. The present article compared different latex intra-oral elastics (5/16 = 7.9 mm). The sample was divided into four groups according to their manufacturer: Group N (Natural latex elastic, Morelli), Group R (Red colour elastic, Morelli) Group Y (Yellow colour elastic, Morelli) and Group G (Green colour elastic, Morelli). Cytotoxicity assays were performed by using cell culture medium containing L-929 line cells (mouse fibroblast). The cytotoxicity was evaluated by using the “dyeuptake” test, which was employed at two different moments (1 and 24 h). Data were compared by analysis of variance (ANOVA) and Tukey’s test (p<0.05). The results showed a significant difference (p<0.05) between the groups N, R, Y, G and the negative cytotoxicity control at 1 and 24 h (p<0.05), it did not have presented significant difference between the groups N, R, Y, G tested (p>0.05) at 1 and 24 h. Morelli intra-oral elastics were found to be highly cytotoxic, regardless of their colour and immersion time.

El látex natural no entra en la categoría de materiales que se sabe del todo inofensivo. El objetivo del presente estudio in vitro es poner a prueba la hipótesis de que no hay diferencia en la citotoxicidad entre elásticos de látex natural de diferentes colores. El presente artículo compara diferentes elásticos intraorales de látex (5/16 =7,9 mm). La muestra se dividió en cuatro grupos según su fabricante: Grupo N (elástico látex, Morelli), Grupo I (elástico de color rojo, Morelli) Grupo Y (elástico de color amarillo, Morelli) y el Grupo G (elástico color verde, Morelli). Pruebas de citotoxicidad se realizaron mediante el uso de medio de cultivo celular que contiene líneas celulares L-929 (fibroblastos de ratón). La citotoxicidad se evaluó mediante el test “dye-uptake”, que se empleó en dos momentos diferentes (1 y 24 h). Los datos se compararon mediante análisis de varianza (ANOVA) y test de Tukey (p<0,05). Los resultados mostraron una diferencia significativa (p<0,05) entre los grupos N, R, Y, G y la negativa citotoxicidad del control en 1 y 24 h (p<0,05), no han presentado diferencias significativas entre los grupos N, R , Y, G probado (p>0,05) en 1 y 24 h. Elásticos intraorales Morelli resultaron ser altamente citotóxicos, independientemente de su color y tiempo de inmersión.

Orthodontic Appliances/adverse effects , Latex/toxicity , Biocompatible Materials/toxicity , Analysis of Variance , Cell Culture Techniques , Latex/chemistry , Materials Testing , Biocompatible Materials/chemistry , Reference Values , Cell Survival
Braz. dent. j ; 21(3): 205-210, 2010. ilus, tab
Article in English | LILACS | ID: lil-556818


This study investigated the cytotoxicity exists between latex and non-latex Orthodontic elastomeric ligatures. Six elastomeric ligatures (1 latex, 2 latex-free and 3 polyurethane) from different manufacturers were divided into 6 groups of 15 elastics each: A (Latex-free, American Orthodontics), M (Polyurethane, Morelli), G (Polyurethane,GAC International), Te (Polyurethane, Tecnident), TP (Natural latex,TP Orthodontics) and U (Latex-free,3M Unitek). The cytotoxicity assay was performed using cell cultures (L929 mouse fibroblast cell line), which were subjected to the cell viability test with neutral red ("dye-uptake") at 1, 2, 3, 7 and 28 days. Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). No statistically significant differences (p>0.05) were observed between Groups M and Te in all experimental periods, except at 2 days. No significant differences (p>0.05) in cell viability were found either among Groups A, G, TP and U or between Groups M and Te at 24 h or among Groups CC, A, G, TP and U at 2 and 28 days. It may be concluded that latex-free elastomeric ligatures from American Orthodontics and Unitek trademarks induced less cell lysis compared to latex and polyurethane ligatures.

Este estudo investigou a citotoxicidade entre ligaduras elásticas ortodônticas de látex e não-látex. Seis ligaduras elásticas de diferentes fabricantes (1 látex, 2 não-látex e 3 poliuretano) foram divididos em 6 grupos de 15 elásticos cada: Grupo A (látex-free, American Orthodontics), M (Poliuretano, Morelli), G (Poliuretano, GAC International), Te (Poliuretano, Tecnident), TP (látex natural, TP Orthodontics) e U (Látex-free, 3M Unitek). O ensaio de citotoxicidade foi realizado utilizando culturas de células (células da linhagem L929, fibroblastos de camundongo) que foram submetidos ao teste de viabilidade celular com vermelho neutro ("dye-uptake") em 1, 2, 3, 7 e 28 dias. A análise de variância (ANOVA), com comparações múltiplas e teste de Tukey foram empregados (α=0,05). Os resultados mostraram que não houve diferença estatisticamente significante entre os Grupos M e Te em todos os tempos experimentais (p>0,05), exceto em 2 dias. Não houve diferença estatisticamente (p>0,05) entre a viabilidade das células nos grupos A, G, TP e U ou entre os grupos M e Te em 24 h, ou entre os grupos CC, A, G, TP e U em 2 e 28 dias. Concluiu-se que as ligaduras elásticas látex-free das marcas American Orthodontics e Unitek induziram menor quantidade de lise celular comparado às ligaduras de látex ou poliuretano.

Animals , Mice , Elastomers/toxicity , Fibroblasts/drug effects , Latex/toxicity , Orthodontic Appliances , Polyurethanes/toxicity , Analysis of Variance , Biocompatible Materials/toxicity , Cells, Cultured , Fibroblasts/cytology , Mouth Mucosa/cytology , Mouth Mucosa/drug effects
J. appl. oral sci ; 17(6): 544-554, Nov.-Dec. 2009. ilus
Article in English | LILACS | ID: lil-534417


There are several studies about the cytotoxic effects of dental materials in contact with the pulp tissue, such as calcium hydroxide (CH), adhesive systems, resin composite and glass ionomer cements. The aim of this review article was to summarize and discuss the cytotoxicity and biocompatibility of materials used for protection of the dentin-pulp complex, some components of resin composites and adhesive systems when placed in direct or indirect contact with the pulp tissue. A large number of dental materials present cytotoxic effects when applied close or directly to the pulp, and the only material that seems to stimulate early pulp repair and dentin hard tissue barrier formation is CH.

Humans , Biocompatible Materials/toxicity , Dental Pulp Capping , Dental Materials/toxicity , Dental Pulp/drug effects , Biocompatible Materials/chemistry , Dental Cements/chemistry , Dental Cements/toxicity , Dental Materials/chemistry , Dentin/drug effects
J. appl. oral sci ; 17(5): 421-426, Sept.-Oct. 2009. ilus, graf
Article in English | LILACS | ID: lil-531390


Cell culture system has been used to evaluate alloy cytotoxicity under different environments, testing the extracts, but the effect of temperature variation on the cytotoxicity of dental alloys has not been analyzed. OBJECTIVE: The aim of the present study was to investigate if temperature variation could affect dental alloy cytotoxicity, testing alloy extracts in an epithelial cell culture system. MATERIAL AND METHODS: Discs of Ni-Cr, Co-Cr-Mo, Ni-Cr-Ti, Ti-6Al-4V and commercially pure titanium (cp Ti) were cast by arc melting, under argon atmosphere, injected by vacuum-pressure. Discs were immersed in artificial saliva and subjected to different temperatures: 37ºC and thermocycling (37ºC/5ºC/37ºC/55ºC/37ºC). After thermocycling, extracts were put in a subconfluent culture during 6 h, and the number of cells and their viability were used to evaluate cytotoxicity in these temperatures. For each alloy, data from temperature conditions were compared by Student's t-test (α=0.05). RESULTS: The cytotoxicity tests with alloy/metal extracts showed that Ni-Cr, Co-Cr-Mo, Ti-6Al-4V and cp Ti extracts (p>0.05) did not affect cell number or cell viability, while Ni-Cr-Ti (p<0.05) extract decreased cell number and viability when the alloy was subjected to thermocycling. CONCLUSION: Within the limitations of the present study, the Ni-Cr-Ti alloy had cell number and viability decreased when subjected to temperature variation, while the other alloys/metal extracts did not show these results.

Humans , Dental Alloys/toxicity , Dental Casting Investment/toxicity , Dental Materials/toxicity , Titanium/toxicity , Alloys/chemistry , Alloys/toxicity , Aluminum Oxide/chemistry , Biocompatible Materials/chemistry , Biocompatible Materials/toxicity , Cell Count , Cell Line, Tumor , Carbon Compounds, Inorganic/chemistry , Cell Survival/drug effects , Chromium Alloys/chemistry , Chromium Alloys/toxicity , Dental Casting Technique , Dental Etching , Dental Alloys/chemistry , Dental Casting Investment/chemistry , Dental Materials/chemistry , Dental Polishing/methods , Diamond/chemistry , Materials Testing , Saliva, Artificial/chemistry , Silicon Compounds/chemistry , Silicon Dioxide/chemistry , Temperature , Titanium/chemistry
Braz. j. otorhinolaryngol. (Impr.) ; 75(5): 665-668, Sept.-Oct. 2009. ilus
Article in English, Portuguese | LILACS | ID: lil-530088


Changes, destructions and interruptions in middle ear ossicular chain architecture may be caused by infection, trauma, tumors, congenital alterations or prior surgeries. Nonetheless, infectious and inflammatory processes, focal or generalized which affect the middle ear are the most prevalent, causing a great demand for ossiculoplasty. Biosilicato® is a new material which can be used in the middle ear with the goal of reconstructing the ossicular chain. It is a bioactive type A vitroceramic, in other words, it binds to bone or soft tissue in a matter of a few hours, thanks to the formation of hydroxy-carbonateapatatie in its contact surface when in contact with body fluids. AIMS: The goal of the present paper is to assess biosilicate ototoxicity and vestibular toxicity in experimental animals, for later use in humans. MATERIALS AND METHODS: This a clinical and experimental study in which otoacoustic emissions were performed before and after the placement of Biosilicate in the middle ear of experimental animals and a scanning electron microscopy was carried out in the cochlea, saccule, utriculus and macula of the semicircular canals after 30 and 90 days to assess oto and vestibular toxicity. RESULTS: There were no signs of oto or vestibular toxicity in any of the groups associated with biosilicate. CONCLUSION: Biosilicate is a safe material to be used in ossiculoplasties

As alterações, destruições e interrupções da arquitetura da cadeia ossicular da orelha média podem ser causadas por infecções, trauma, tumores, alterações congênitas ou cirurgias prévias. Entretanto os processos inflamatórios e infecciosos, focais ou generalizados que acometem a orelha média são os mais prevalentes, gerando uma enorme demanda de ossiculoplastias. O Biosilicato® é um novo material que pode ser usado em orelhas médias com o objetivo de reconstruir a cadeia ossicular. Constitui-se de uma vitrocerâmica bioativa do tipo A, ou seja, que se liga a tecido ósseo ou a tecido mole em algumas horas, devido à formação de hidroxicarbonatoapatita em sua superfície de contato quando em contato com fluidos corpóreos. OBJETIVO: O objetivo deste trabalho é avaliar a ototoxicidade e vestibulotoxicidade do Biosilicato em cobaias, para posterior utilização em humanos. MATERIAL E MÉTODO: Trata-se de um estudo clínico e experimental, onde foram realizadas emissões otoacústicas antes e após a colocação de Biosilicato na orelha média de cobaias e realizada microscopia eletrônica de varredura da cóclea, sáculo, utrículo e máculas dos canais semicirculares após 30 e 90 dias para avaliar a oto e vestibulotoxicidade. RESULTADOS: Não houve sinais de oto ou vestibulotoxicidade em nenhum dos grupos relacionados ao Biosilicato. CONCLUSÃO: O Biosilicato é um material seguro para ser usado em ossiculoplastias.

Animals , Guinea Pigs , Male , Biocompatible Materials/toxicity , Ceramics/toxicity , Ear, Inner/drug effects , Silicates/toxicity , Drug Evaluation, Preclinical , Ear, Inner/ultrastructure , Microscopy, Electron, Scanning , Ossicular Prosthesis , Ossicular Replacement , Otoacoustic Emissions, Spontaneous/drug effects
Rev. odonto ciênc ; 24(2): 168-172, abr.-jun. 2009. ilus, tab
Article in Portuguese | LILACS, BBO | ID: lil-518608


Objetivo: Avaliar a citotoxicidade de parafusos expansores confeccionados com aço inoxidável ou compósito. Métodos: Foram avaliados 6 parafusos expansores divididos em 2 grupos de acordo com o material: expansor metálico e expansor de compósito. Três grupos controle foram utilizados: controle positivo (cilindro de amálgama), controle negativo (bastão de vidro) e controle de célula (células não expostas). Os expansores esterilizados foram imersos em meio mínimo essencial de Eagle por 24 h, onde se procedeu a remoção do sobrenadante e contato com fibroblastos L929. Após contato com o meio as células foram incubadas por 24 h, sendo adicionados 100 μL do corante vermelho neutro a 0,01%, seguido por incubação por 3 h e fixação das células. A citotoxicidade foi analisada em 4 períodos: 24, 48, 72 e 168 h. A contagem de células viáveis foi realizada com espectrofotômetro (λ = 492 nm) e os dados foram analisados por ANOVA. Resultados: Os grupos controle positivo (amálgama) foram estatisticamente diferentes dos demais grupos. Não houve diferença estatística na comparação entre os demais grupos e períodos. Conclusões: Os resultados sugerem que os parafusos expansores testados não apresentam citotoxicidade significativa conforme o desenho experimental utilizado.

Objective: To evaluate the cytotoxicity of two palatal expanders made of stainless steel or composite. Methods: Six expanders were divided into two experimental groups: metallic expander and composite expander. Three control groups also were assessed: positive control (amalgam), negative control (glass stick), and control cell (cells not exposed to any material). The sterilized expanders were immersed into Eagle's minimum essential medium for 24 h, and the contact assay was performed using L929 fibroblasts. The cells were incubated for 24 h, and 100 μL of 0.01% neutral-red staining solution were added followed by incubation for 3 h and cell fixation. Cytotoxicity was evaluated at four different periods of time: 24, 48, 72, and 168 h. Counting of viable cells was performed by using a spectrophotometer at a wavelength of 492 nm, and data were analyzed by ANOVA. Results: The positive control groups (amalgam) were statistically different from the other groups. No difference of cytotoxicity was found among the groups and periods of time. Conclusions: The tested metallic and composite expanders showed no significant cytotoxicity within this experimental design.

In Vitro Techniques , Biocompatible Materials/toxicity , Palatal Expansion Technique/instrumentation , Case-Control Studies , Cell Culture Techniques
Rev. Asoc. Odontol. Argent ; 96(1): 63-71, ene.-mar. 2008. ilus
Article in Spanish | LILACS | ID: lil-492402


Una revisión exhaustiva de la bibliografía revela que existe una considerable cantidad de publicaciones relacionadas con las propiedades biológicas de los materiales de obturación endodóntica. La mayoría de las mismas están referidas a los ensayos preclínicos in vitro e in vivo de acuerdo a las normas establecidas por los diferentes organismos internacionales. Estas pruebas incluyen los ensayos de citotoxicidad in vitro y la implantación de materiales problema en el tejido celular subcutáneo, músculo o hueso de pequeños animales de laboratorio. Los resultados de estas diferentes metodologías no presentan una correlación definida. Como consecuencia de estas observaciones, los únicos ensayos de biocompatibilidad considerados como relevantes son los así denominados ensayos de uso clínico. En esta tercera entrega se hace un delineamiento de los ensayos requeridos para el análisis biológico de los materiales de obturación previos a su aceptación para ser utilizados rutinariamente en humanos.

Animals , Materials Testing , Biocompatible Materials/toxicity , Root Canal Filling Materials/chemistry , Clinical Trials as Topic , Dental Cements/toxicity , Toxicity Tests/methods
Braz. dent. j ; 16(1): 3-8, Jan.-Apr. 2005.
Article in English | LILACS | ID: lil-415736


Este estudo in vivo avaliou o potencial irritativo do EDTA, EGTA, ácido cítrico e soro fisiológico (controle) durante a fase exsudativa do processo inflamatório. Aplicou-se, intravenosamente na veia caudal lateral de 32 ratos machos da linhagem "Wistar", variação albina, 20 mg/kg de azul de Evans 2%. Em seguida, no tecido subcutâneo da região dorsal dos animais injetou-se 0,01 mL das soluções testes. Após os intervalos de ½, 1, 3 e 6 horas, os animais foram sacrificados, suas peles dorsais foram excisadas e submetidas à análise do corante extravasado pela espectrofotometria de absorção de luz. Os dados obtidos foram avaliados pela análise de variância a 2 critérios e teste de Tukey. Em todos os períodos de tempo estudados, os maiores valores de corante extravasado foram observados no grupo do EDTA seguido pelos grupos do EGTA e ácido cítrico, em comparação ao grupo controle. Houve diferença estatisticamente significante entre todas as soluções testadas (p<0.01). Quando considerado o fator tempo, notou-se diferença significante entre os grupos de 3 e 6 horas (p<0.05). Entretanto, não houve diferença entre os grupos de tempo de ½ e 1 hora. Dentre os ácidos orgânicos avaliados, os resultados demonstraram que o ácido cítrico apresentou o menor potencial irritativo.

Animals , Male , Rats , Capillary Permeability/drug effects , Chelating Agents/toxicity , Citric Acid/toxicity , Edetic Acid/toxicity , Egtazic Acid/toxicity , Root Canal Irrigants/toxicity , Biocompatible Materials/toxicity , Coloring Agents , Evans Blue , Inflammation/chemically induced , Rats, Wistar , Sodium Chloride/toxicity
Article in Malayalam | WPRIM | ID: wpr-629952


Biomaterials intended for end-use application as bone-graft substitutes have to undergo safety evaluation. In this study, we investigated the in vitro cytotoxic effects especially to determine the mode of death of two hydroxyapatite compounds (HA2, HA3) which were synthesized locally. The methods used for cytotoxicity was the standard MTT assay whereas AO/PI staining was performed to determine the mode of cell death in HA treated L929 fibroblasts. Our results demonstrated that both HA2 and HA3 were not significantly cytotoxic as more than 75% cells after 72 hours treatment were viable. Furthermore, we found that the major mode of cell death in HA treated cells was apoptosis. In conclusion, our results demonstrated that these hydroxyapatite compounds are not cytotoxic where the mode of death was primarily via apoptosis.

Apoptosis/drug effects , Biocompatible Materials/toxicity , Bone Substitutes/toxicity , Cell Death/drug effects , Durapatite/toxicity , L Cells , Prostheses and Implants
Article in Malayalam | WPRIM | ID: wpr-629950


Hydroxyapatite is the main component of the bone which is a potential biomaterial substance that can be applied in orthopaedics. In this study, the biocompatibility of this biomaterial was assessed using an in vitro technique. The cytotoxicity and genotoxicity effect of HA2 and HA3 against L929 fibroblast cell was evaluated using the MTT Assay and Alkaline Comet Assay respectively. Both HA2 and HA3 compound showed low cytotoxicity effect as determined using MTT Assay. Cells viability following 72 hours incubation at maximum concentration of both HA2 and HA3 (200 mg/ml) were 75.3 +/- 8.8% and 86.7 +/- 13.1% respectively. However, the cytotoxicity effect of ZnSO4.7H2O as a positive control showed an IC50 values of 46 mg/ml (160 microM). On the other hand, both HA2 and HA3 compound showed a slight genotoxicity effect as determined using the Alkaline Comet Assay following incubation at the concentration 200 mg/ml for 72 hours. This assay has been widely used in genetic toxicology to detect DNA strand breaks and alkali-labile site. The percentage of the cells with DNA damage for both substance was 27.7 +/- 1.3% and 15.6 +/- 1.0% for HA2 and HA3 respectively. Incubation of the cells for 24 hours with 38 microg/ml (IC25) of positive control showed an increase in percentage of cells with DNA damage (67.5 +/- 0.7%). In conclusion, our study indicated that both hydroxyapatite compounds showed a good biocompatibility in fibroblast cells.

Biocompatible Materials/toxicity , Bone Substitutes/toxicity , Cell Survival/drug effects , DNA Damage , Hydroxyapatites/toxicity , L Cells , Mutagenicity Tests , Prostheses and Implants
Article in Malayalam | WPRIM | ID: wpr-629949


The present study is aimed at finding the mutagenicity and cytotoxicity of dense form of synthetic hydroxyapatite (Source: School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia) in the blood of sheep. The biomaterial was implanted in the tibia of Malin, an indigenous sheep breed of Malaysia. Blood was collected from the sheep before implantation of the biomaterial, cultured and a karyological study was made. Six weeks after implantation, blood was collected from the same animal, cultured and screened for chromosome aberrations. The mitotic indices and karyological analysis indicated that the implantation of synthetic hydroxyapatite (dense form) did not produce any cytotoxicity or chromosome aberrations in the blood of sheep.

Biocompatible Materials/toxicity , Bone Substitutes/toxicity , Bone and Bones/pathology , Cell Survival/drug effects , Chromosome Aberrations , Hydroxyapatites/toxicity , Karyotyping , Mutagenicity Tests , Prostheses and Implants , Sheep
Pesqui. odontol. bras ; 17(2): 113-118, Apr.-Jun. 2003. ilus, graf
Article in English | LILACS | ID: lil-347420


Cyanoacrylate has been used in medicine and dentistry for many years. It has been used as a postextraction dressing and retrograde filling material in endodontic surgery. The aim of this study was to evaluate the cytotoxic effects of Histoacryl and other two homologue ethyl cyanoacrylates, Super Bonder and Ultrabond, on cultured fibroblasts, using the Trypan blue dye exclusion assay. The cyanoacrylates were applied to round glass coverslips, which were placed in contact with NIH 3T3 cells. After 0, 6, 12 and 24 h (short-term assay; viability) and 1, 3, 5 and 7 days (long-term assay; survival), the cells were examined under phase light microscopy and counted. The data were compared by the Kruskal-Wallis test. In the short-term experiments, only the cultures of the Ultrabond group (GIV) presented significant smaller percentages of cell viability than the cultures of the other groups (GI: control; GII: Super Bonder; GIII: Histoacryl). Although the cultures of the Super Bonder group (GII) presented smaller percentages of cell viability than cultures of the other groups (GI, GIII, GIV) at the long-term assay, this group was the only experimental group presenting a continuous and progressive cell growth. Our results have shown an in vitro biocompatibility of Histoacryl and ethyl cyanoacrylate homologues. These cyanoacrylates could therefore be of importance for endodontic purposes

Animals , Mice , Biocompatible Materials/toxicity , Cyanoacrylates/toxicity , Retrograde Obturation , Root Canal Filling Materials/toxicity , Cell Culture Techniques , Cell Division , Cell Survival , Composite Resins/toxicity , Enbucrilate/toxicity , /drug effects