Jan 24, 2013
Genotoxicity of dental restoration nanocomposite evaluated
Dental caries, or tooth decay, is a health issue affecting people worldwide. To restore teeth affected by the caries, dental fillings are used and these can be produced by different kinds of materials. A potentially effective material for dental restoration is nanocomposite. A dental restoration nanocomposite produced at the School of Dental Sciences, Universiti Sains Malaysia, containing 35wt% of nanosilica fillers in the size range of 10–20 nm and dubbed KelFil shows good promise to be used in dentistry by virtue of the genotoxicity results obtained so far.
Biomaterials to be applied in dentistry should be functional, aesthetic and most importantly biocompatible. Being biocompatible suggests that the biomaterial is safe for patients' use. One of the tests for assessing biocompatibility is the genotoxicity test.
The International Organization for Standardization (ISO) through the Biological Evaluation of Medical Devices (10993-Part 3) (2003) guidelines has stated a series of in vitro tests using mammalian cells for genotoxicity testing. Two of the tests are the Comet assay and the chromosome aberration (CA) test.
The Comet assay enables researchers to study the DNA damaging effect of a material. This test is not only efficient, but also cost effective and only requires a small number of cells. The presence of a comet-shaped cell indicates that the material causes damage to DNA.
The second test – the CA test – is used to detect any aberration in the chromosomes due to exposure to the test material. The aberration could be numerical or structural.
The current work shows that the locally produced dental restoration nanocomposite did not produce any significant DNA damage or chromosomal aberrations.
Full details can be found in the journal Nanotechnology.
About the author
The study was conducted by researchers from the School of Dental Sciences, Universiti Sains Malaysia, Malaysia. Marahaini Musa is an MSc candidate at the School of Dental Sciences. She conducted the experiments with ideas conceived by associate professor Dr T P Kannan. Dr Dasmawati Mohamad and Prof. Prof. Ismail Ab Rahman were involved in the synthesis of this material.