Know Nano in Dentistry

Commentary: Nanotechnology is the art and science of engineering material on a scale of fewer than 100 nm1. One nanometer is 1 billionth of a meter. For easy comparison of nanometer to a meter, it is the same as the size of a marble to the size of the earth2. The word “nano” is borrowed from the Greek term which means “dwarf” and the word nanotechnology was coined by prof. Kerie E. Drexler3. Though this technology sounds relatively new, humans have been using the technique of shaping the matter since ages, such as processing of vulcanized rubber and sharpening of dental instruments these are all based on manipulating the particles at the molecular or atomic level. The concept of this technology is that when a particle is broken down into atomic or molecular particles, one can discover innumerable possibilities and potential of the basic particle, and also analysis can be made to the level of manipulating these particles which can help in changing the characteristics of the material. This technology has already been in use in various fields such as machinery production, defense industry, space and aircraft technologies, information and communication systems, energy systems, chemistry, environment, molecular biology, gene engineering, Food processing, and medicine. The application of this technology in the field of dentistry is leading to the evolution of a new field called Nano-Dentistry. This can help in the upkeep of near-perfect hygiene of the oral cavity by employing various nanomaterials, including tissue engineering. The information obtained at a level of nanoscale has the probability to change the fate of dental practice by advancing all aspects of dental diagnostics and therapeutics into a new dimension of patient care beyond conventional oral care procedures4. Two approaches have been formulated for the manufacture of nanoparticles i.e. Top-down approach, where the large pieces of material are reduced down to the nanoscale & the Bottom-up approach creates products by building them up from nanoscale components5. Nanomaterials in dentistry can be used with composites, ceramics, polymers, and implant modifications6. This technology also has revolutionized the way one treats dental caries using metals, oxides, and other nanoparticles due to their distinct physio-chemical properties such as anti-microbial (E.g. Gold, Silver, Titanium dioxide, etc.), anti-inflammatory (E.g. Gold, Silver, Titanium oxide and zinc oxide) and re-mineralizing potential (E.g. Hydroxyapatite, Casein phosphor-peptide, tin chitosan, etc.)7 There are also certain challenges faced by nano-dentistry such as engineering challenges which include, feasibility for mass production and adjusting of molecular-scale parts. Biological challenges include developing particles that are biocompatible to both nature and the human body and Social challenges including ethical, regulation, and safety issues3. The large-scale use of nanoparticles in a vast range of products for the human application can result in increased risk for toxicity. An Invitro study published by Heravi8 et al, accessing the cytotoxicity of an orthodontic composite containing titanium dioxide (Tio2) nanoparticles revealed that the material containing the nanoparticles has a comparable or even lower toxicity than its nanoparticles free composite. Another study published by Libonati9 et al found that nanoparticles can leaching-out from composite material caused embryotoxicity in the blastocyst of mouse invitro, while there was no observable toxicity when implanted subcutaneously in-vivo. Though there is an infinite number of possibilities and applications of nanotechnology, one must also understand the associated risks of nanoparticles and its cost effectiveness10.