et al. 2018). Such technology efficiently diagnoses cell changes. Moreover, the false-

negative rate of diagnosis is nearly zero (Oldenburg et al. 2006).

Nanoshells are a collection of minuscule beads with outer metallic layers (usually

gold) that absorbs the infrared radiation and produces intense heat. This heat is used

in the selective destruction of cancer cells without affecting the proximal healthy

cells (Kanaparthy and Kanaparthy 2011). Recently, silver nanotechnology has also

shown promising action against biofilms due to its high affinity towards the nega-

tively charged microorganism and its ability to inactivate critical physiological

functions within the microorganism (Guzman et al. 2012). The non-invasive real-

time diagnosis and effective therapeutic action offered by nanoparticles thus result in

timely detection and prompt treatment of oral cancer lowering the mortality rate

caused by the disease.

10.3.5 Nanoparticles in Dentifrices

Incorporation of calcium carbonate nanoparticles in toothpaste has shown

favourable results in enamel remineralisation. Dentifrobots are very small (1–10

micron) dentifrices delivered in the form of mouthwash or toothpaste. Using these

dentifrobots at least once a day for cleaning the supragingival and subgingival

surfaces leads to metabolisation of trapped organic matter into harmless and

odourless vapours and continuous calculus debridement. These nanorobots

incorporated in the dentifrices are minute mechanical devices that can safely deacti-

vate themselves if swallowed. They are designed to precisely identify the oral

pathogenic bacteria and allow the other harmless microflora to flourish in the oral

cavity (Mehta and Subramani 2012).

10.3.6 Orthodontic Treatment

Nanotechnology has enormously influenced orthodontic therapy, making it painless,

less traumatic to the periodontal structures, and reducing relapse chances.

Nanoparticles of zinc oxide and chitosan are added to composite resins to improve

the bond strength with added antibacterial effect. Such orthodontic nanocomposites

overcome the common problem of bond failure and reduce the caries development

risk due to its antibacterial action. An essential component upon which orthodontic

therapy’s success largely depends is the orthodontic bracket which is instrumental in

carrying the archwire forces to the teeth. The addition of alumina nanoparticles

augments the strength and corrosion resistance of these orthodontic brackets. One of

the significant challenges in orthodontic therapy is overcoming the frictional force

produced during tooth movement without excessive orthodontic forces that may

cause loss of anchorage and root resorption. Orthodontic nanorobots are implicated

in manipulating the periodontal tissues, allowing rapid and painless tooth straight-

ening, rotating and vertical repositioning in lesser time than usual. Coating the

stainless-steel wires with carbon nitride (Wei et al. 2010), zinc oxide (Kachoei

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