Application of Nanotechnology in Dentistry

 

B. Ssneha

Saveetha Dental College, Chennai, INDIA.

*Corresponding Author E-mail:ssnehab95@gmail.com

 

 

ABSTRACT:

Nanotechnology means manipulating matter at the nanometer level and its application in medicine is known as nanomedicine. Nanotechnology’s most notable contribution to dentistry is the restoration of tooth structure with nanocomposites. These materials can offer esthetic and strength advantages over conventional microfilled and hybrid resin based composite systems in terms of smoothness, polishibility, precision of shade characterization, flexural strength and micro hardness. Operating on such a minute aspect provides a perspective to envision the restoration of tooth at a level that offers closer approximation of its individual anatomic structures. Currently laboratory dental research is exploring designs for restorative systems that approximate the very process by which dental enamel is formed.

 

KEYWORDS: Nanostructure, dental restorative, nanomedicine, recent advances, future research.

 


INTRODUCTION:

First started in 1959, by physicist Richard P Feynman nanotechnology has been viewed as an inevitable development in the progress of science. ‘NANO is derived from the Greek word which means ‘dwarf’. Nanotechnology is the science of manipulating matter which is measured in billionths of a meter or nanometer and is roughly the size of 2 or 3 atoms1.  It’s use in medical and dental field has been since the early 1990s. Nanoparticles, nanospheres, nanorods, nanotubes, dendrimers and other nanostructures have been studied for its use in biologic tissues and systems. There is increasing interest in this field that it is believed that nanotechnology will lead to the emergence of a new field called nanomedicine. Since the last decade, research is been conducted for the use of nanotechnology in dentistry and the recent revolution is the use of nanocomposites in dentistry. Nanomaterials stems maybe developed with the idea that they may be used to manipulate the structure of materials to provide dramatic improvements in electrical, chemical, mechanical and optical properties2. Today, the remarkable development in the field of nanotechnology has become the most highly energized discipline in the field of science and technology3.

 

CURRENT DEVELOPMENTS IN THE FIELD OF NANOTECHNOLOGY:

Current research is focused on an extensive array of different nanoscale structures. The various nanostructures include-4

Ø  Nanopores

Ø  Nanoshells

Ø  Nanotubes

Ø  Quantum dots

Ø  Dendrimers

 

NANORODS:

These are of interest in restoration. Chen and colleagues have synthesized enamel-prism-like hydroxyapatite nanorods that exhibit self-assembly properties5. As they are similar to the basic crystalline structure of dental enamel, nanorods contribute to an artificial approximation of a naturally-occurring structure.

 

NANOSPHERES:

Nanosphere assembly with calcium phosphate deposition and amelogenin nanochain assembly are used in a restorative context6.

 

NANOTUBES:

Titanium oxide nanotubes have been studied in-vitro and have been known to accelerate the kinetics of hydroxyapatite formation mainly in relation with bone-growth applications for dental-implant coatings7.

 

 

NANOFIBERS: 

Recently, nanofibers have been used to create ceramics containing hydroxyapatite and fluor-hydroxyapatite8. Recently used nanofibrillar silicate crystals in dental composites is the widely used 2, 2’-bis-[4-(methacryloxypropoxy)-phenyl]-propane (Bis-GMA) with triethylene glycol dimethacrylate (TEGDMA) added as a thinning agent (9, 10). Added in the correct proportions and with the uniform distributions of the crystals and fibers, nanofibers are shown to improve the physical properties of the composites9, 10.

 

DENDRIMERS:

Dendrimers and dendritic copolymers have been studied to a lesser extent than other nanostructures in relation to dental composite applications. Combinations of specific polymers have been suggested to improve the efficacy of restorative applications11, 12, and 13.

 

NANODENTISTRY:

Nanodentistry will bring a revolution in oral health through the use of nanomaterials; biotechnology which includes tissue engineering and nanorobotics. Oral health and disease may influence specific diagnostic and treatment modalities14.

 

IN LOCAL-ANAESTHESIA:

In this aspect, a colloidal suspension containing millions of active analgesic micron-size dental robots will be placed in the patient’s gingival. During its contact with the crown or mucosa, the ambulating nanorobots will reach the pulp through the gingival sulcus, lamina propria and dentinal tubules. After getting itself installed in the pulp, the analgesic dental robots will be commanded by the dentist to shut down the sensitivity in the required tooth function and nerve traffic.

 

DENTIFROBOTS:

Subocclusal dwelling nanorobotic dentrifice which are delivered by mouthwash or toothpaste could clear all the supra and sub gingival surface s at least once a day. These invisible, small(1-10 micron),dentifrobots crawling at 1-10 microns/sec, are inexpensive, purely mechanical which would safely deactivate themselves when swallowed and be programmed with strict occlusal avoidance protocol15.

 

ORTHODONTIC TREATMENT:

Orthodontic nanorobots will directly manipulate the periodontal tissues delivering rapid and painless tooth straightening, rotating and vertical repositioning within minutes to hours15.

 

DIAGNOSIS AND TREATMENT OF ORAL CANCER:

DIAGNOSIS- Multiplexing Modality- It can sense large numbers of different biomolecules simultaneously in real time. It can be used to diagnose diabetes mellitus, cancer, and detection of bacteria, fungi and viruses.

 

TREATMENT: Promotes drug delivery across Blood-brain barrier and is more effective in the treatment of brain tumours, Alzheimer’s, Parkinson’s disease. Nanovectors for gene therapy are used as non-viral gene delivery systems15.

 

NANOCOMPOSITES:

Recently, Nanoproducts Corporation has manufactured nanoparticles that are uniformly distributed in resins or coatings to produce nanoparticles. The nanofiler includes aluminosilicate powder with a mean particle size of 80 nm and a 1:4 ratio of alumina to silica and a refractive index of 1.50816. Nanocomposites have been known to offer desirable overall esthetics, function and biocompatibility for anterior restorations. In a two-part series published in 2004 by Terry, initial clinical recognition of nanocomposites in esthetics dental armamentarium is mentioned17, 18. Notable improvements in surface smoothness have been reported for nanofills compared to microfills19, 20.

 

Advantages include-

Ø  Superior hardness

Ø  Superior flexural strength

Ø  Enhanced handling properties.

 

NANOSOLUTION:

They produce unique nanoparticles which can be used as bonding agents which ensures homogeneity and that the adhesive is perfectly mixed every time.

TRADE NAME: Nanotech Elite H-D16.

 

IMPRESSION MATERIALS:

Nanofillers are used along with vinylpolysiloxanes, producing unique variety of siloxane impression materials. This material has good flow. Better hydrophilic properties and enhanced detail precision16.

 

NANONEEDLES:

Suture needles incorporated into nano-sized stainless steel crystals are recently developed. Nanotweezers are also under research which when developed will make cell-surgery possible in the near future16.

 

ARE NANOROBOTS SAFE?

The nonpyrogenic nanorobots which are used in vivo include bulk Teflon, carbon powder and monocrystal sapphire. Pyrogenic include alumina, silica, and trace elements like copper and zinc. Nanorobots may release inhibitors, antagonists or down regulators in a targeted fashion which may selectively absorb endogenous pyrogens, modify them and release back into the body in a harmless inactivated form21.

 

CHALLENGES POSED TO NANODENTISTRY:

Ø   Problem with precise positioning and assembly of molecular scale.

Ø  Production of mass nanorobot technique is not economical.

Ø  Biocompatibility

Ø  Problem with simultaneous coordination of activities of large quantities of independent micron-scale products.

Ø  Social issues such as public acceptance, ethics, regulation and human safety.

FUTURE OF NANODENTISTRY:

Surgical nanorobots are being developed guided by human surgeons which can be introduced into the body through vascular system or cavities. This can perform various functions such as searching for pathology, diagnosing and correcting lesions by nanomanipulation assisted by onboard computer while maintaining contact with the supervising surgeon through coded ultrasound signals22. Nanofillers integrated with vinylsiloxanes produce unique addition siloxane impression material which has good flow, better hydrophilic properties thereby giving rise to fewer voids at margins and better pouring and enhanced detail precision23. Nanotechnology has developed various kinds of fibers such as polymer nanofibers with diameters in the nanometer range, possesses a large surface area per unit mass24,25. Carbon fibers with nanometer dimensions have shown a selective increase in osteoblast adhesion which is necessary for successful dental implant applications due to a higher degree of nanometer surface toughness26.

 

CONCLUSION:

Currently nanotechnology has made the greatest impact on restorative dentistry by providing refinements to already clinically proven RBC systems. The use of nanotechnology to manufacture dental restorative composite system offers high translucency, high polish and polish retention similar to those of microfills which maintain physical properties and wear resistance similar to commercial hybrid composites. Combination of two types of nanoparticles provides a best combination of physical properties. With further research in esthetics, long-term polish retention and other optimized physical properties it is said that this novel nanocomposites system will be useful for all anterior and posterior restorative applications.

 

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Received on 01.08.2013       Modified on 02.10.2013

Accepted on 15.10.2013      © RJPT All right reserved

Research J. Pharm. and Tech. 7(1): Jan. 2014; Page  81-83