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In Vitro Cytotoxicity Assessment of an Orthodontic Composite Containing Titanium-dioxide Nano-particles.

Heravi F, Ramezani M, Poosti M, Hosseini M, Shajiei A, Ahrari F - J Dent Res Dent Clin Dent Prospects (2013)

Bottom Line: Results.No significant differences were found in cell viability percentages between the two groups on the other days (P>0.05).The orthodontic adhesive containing TiO2 nano-particles indicated comparable or even lower toxicity than its nano-particle-free counterpart, indicating that incorporation of 1 wt% TiO2 nano-particles to the composite structure does not result in additional health hazards compared to that occurring with the pure adhesive.

View Article: PubMed Central - HTML - PubMed

Affiliation: Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.

ABSTRACT
Background and aims. Incorporation of nano-particles to orthodontic bonding systems has been considered to prevent enamel demineralization around appliances. This study investigated cytotoxicity of Transbond XT adhesive containing 1 wt% titanium dioxide (TiO2) nano-particles. Materials and methods. Ten composite disks were prepared from each of the conventional and TiO2-containg composites and aged for 1, 3, 5, 7 and 14 days in Dulbecco's Modified Eagle's Medium (DMEM). The extracts were obtained and exposed to culture media of human gingival fibroblasts (HGF) and mouse L929 fibroblasts. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results. Both adhesives were moderately toxic for HGF cells on the first day of the experiment, but the TiO2-containing adhesive produced significantly lower toxicity than the pure adhesive (P<0.05). No significant differences were found in cell viability percentages between the two groups on the other days (P>0.05). There was a significant reduction in cell toxicity with increasing pre-incubation time (P<0.001). L929 cells showed similar toxicity trends, but lower sensitivity to detect cytotoxicity of dental composites. Conclusion. The orthodontic adhesive containing TiO2 nano-particles indicated comparable or even lower toxicity than its nano-particle-free counterpart, indicating that incorporation of 1 wt% TiO2 nano-particles to the composite structure does not result in additional health hazards compared to that occurring with the pure adhesive.

No MeSH data available.


Related in: MedlinePlus

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Mentions: Conventional Transbond XT adhesive served as the control group and Transbond XT containing TiO2 nano-particles was regarded as the experimental group. Ten test specimens were prepared from each adhesive with the use of polyethylene discs measuring 8 mm in diameter. The adhesive material was inserted between the two polyethylene disks and pressed by glass slabs to provide uniform thickness and surface smoothness ( Figure 1A). The excess material was removed with a dental explorer from around the disks and each specimen was photopolymerized for 40 seconds by a quartz tungsten halogen curing apparatus (Coltolux 75; Coltene/Whaledent Inc., Cuyahoga Falls, OH, USA) at a maximum intensity of 1000 mW/cm2.


In Vitro Cytotoxicity Assessment of an Orthodontic Composite Containing Titanium-dioxide Nano-particles.

Heravi F, Ramezani M, Poosti M, Hosseini M, Shajiei A, Ahrari F - J Dent Res Dent Clin Dent Prospects (2013)

© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3935549&req=5

Mentions: Conventional Transbond XT adhesive served as the control group and Transbond XT containing TiO2 nano-particles was regarded as the experimental group. Ten test specimens were prepared from each adhesive with the use of polyethylene discs measuring 8 mm in diameter. The adhesive material was inserted between the two polyethylene disks and pressed by glass slabs to provide uniform thickness and surface smoothness ( Figure 1A). The excess material was removed with a dental explorer from around the disks and each specimen was photopolymerized for 40 seconds by a quartz tungsten halogen curing apparatus (Coltolux 75; Coltene/Whaledent Inc., Cuyahoga Falls, OH, USA) at a maximum intensity of 1000 mW/cm2.

Bottom Line: Results.No significant differences were found in cell viability percentages between the two groups on the other days (P>0.05).The orthodontic adhesive containing TiO2 nano-particles indicated comparable or even lower toxicity than its nano-particle-free counterpart, indicating that incorporation of 1 wt% TiO2 nano-particles to the composite structure does not result in additional health hazards compared to that occurring with the pure adhesive.

View Article: PubMed Central - HTML - PubMed

Affiliation: Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.

ABSTRACT
Background and aims. Incorporation of nano-particles to orthodontic bonding systems has been considered to prevent enamel demineralization around appliances. This study investigated cytotoxicity of Transbond XT adhesive containing 1 wt% titanium dioxide (TiO2) nano-particles. Materials and methods. Ten composite disks were prepared from each of the conventional and TiO2-containg composites and aged for 1, 3, 5, 7 and 14 days in Dulbecco's Modified Eagle's Medium (DMEM). The extracts were obtained and exposed to culture media of human gingival fibroblasts (HGF) and mouse L929 fibroblasts. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results. Both adhesives were moderately toxic for HGF cells on the first day of the experiment, but the TiO2-containing adhesive produced significantly lower toxicity than the pure adhesive (P<0.05). No significant differences were found in cell viability percentages between the two groups on the other days (P>0.05). There was a significant reduction in cell toxicity with increasing pre-incubation time (P<0.001). L929 cells showed similar toxicity trends, but lower sensitivity to detect cytotoxicity of dental composites. Conclusion. The orthodontic adhesive containing TiO2 nano-particles indicated comparable or even lower toxicity than its nano-particle-free counterpart, indicating that incorporation of 1 wt% TiO2 nano-particles to the composite structure does not result in additional health hazards compared to that occurring with the pure adhesive.

No MeSH data available.


Related in: MedlinePlus