New bioactive dental filling material promises to be teeth-friendly

Prof. S. Balakumar and D. Durgalakshmi at the National Centre for Nanoscience and Nanotechnology, University of Madras
Prof. S. Balakumar and D. Durgalakshmi at the National Centre for Nanoscience and Nanotechnology, University of Madras

Cuttack : A team of Indian
scientists has developed a new technique that promises to help produce bioactive
dental filling materials which will take much lesser time for formation of new
bone tissues.

Bioactive dental filling materials are gaining
popularity as they last longer, restore minerals in teeth and slow down
secondary tooth decay more effectively. Previously,
a technique called melt-derived method was used. The materials were produced
without crystallization and were of micron size.

Now scientists have synthesized a crystallization
induced, strontium-based
nano-sized material using a simpler sol-gel assisted microwave method. The
effect of crystallization on the product and its reactivity is the main focus
of the findings.

Researchers claim that compared with commercially
available micron-level materials the newly synthesized nano-structured
materials have a higher rate of mineralisation of bone apatite, and thus cutting
down on the time taken for the formation of new bone tissues.

Normally calcium is used for production of
biomaterials. In the present work, scientists synthesized nano-bioactive
materials with the same base composition as that for commercially available
biomaterial called Bioglass 45S5 but by substituting calcium with strontium and
controlling the particle size at the nano-scale.

The sol-gel assisted microwave method, which was
employed for the process, involves conversion of monomers into a colloidal
suspension ‘sol’, which is polymerised to form the ‘gel’ which is then heated
at high temperature to give the final solid product.

Researchers said the new material acted as a better
agent for occluding or blocking exposed dentin tubules and for decreasing
hypersensitivity more effectively. It can kill microorganisms causing tooth
decay faster and can also be used for bone regeneration applications, they

Speaking to India Science Wire, lead scientist Prof. S. Balakumar of the National Centre for Nanoscience and Nanotechnology, University of Madras, said,

“it takes only two days to prepare the bioactive glass by the new technique in laboratory. The process is highly scalable for commercial purposes”.

The scientists conducted crystal structure analysis,
dentin remineralisation, antibacterial efficacy test against dentin bacterial
strains, and computer simulation interaction of the material with salivary
metabolites. Multinuclear solid-state NMR studies of the product provided
detailed atomistic insight into the presence of crystalline mineral phases in
the bioactive material. Surface morphological evaluation showed that strontium
plays a major role in the morphological determination of the material. The biomaterial
produced has been tested as per the global standards for biomaterials for
mechanical, biocompatible applications. The researchers said that they are
working on developing a nano-bioglass from natural calcium and phosphate source
to further decrease the cost.

The National Centre for Nanoscience and
Nanotechnology, University of Madras, conducted the study in collaboration
with, Centre for Advanced Studies in Crystallography & Biophysics,
University of Madras, National Chemical Laboratory, Pune, and Department of
Medical Physics, Anna University. The team included D. Durgalakshmi, R. Ajay
Rakkesh, M. Kesavan, S. Ganapathy, T. G. Ajithkumar, S. Karthikeya and S.
Balakumar. The study was funded by Department of Biotechnology (DBT). The
research findings have been published in the journal Biomaterial Science.

By Dr Sanghamitra Deobhanj

(India Science Wire)