Journal of International Oral Health

REVIEW ARTICLE
Year
: 2022  |  Volume : 14  |  Issue : 4  |  Page : 357--362

Use of nanoparticles in pediatric dentistry: A narrative review


Sonu Acharya1, Brinda S Godhi2, Sonali Saha3, Bismay Singh1, Kavita Dinsa3, Jitendra Bhagchandani4, Ashesh Gautam5,  
1 Department of Pediatric and Preventive Dentistry, Institute of Dental Sciences, SOA (Deemed to be University), Bhubaneswar, Odisha, India
2 Department of Pediatric and Preventive Dentistry, JSS Dental College and Hospital, JSS Academy of Higher Education and Research, Mysuru, Karnataka, India
3 Department of Pediatric and Preventive Dentistry, Sardar Patel Post Graduate Institute of Dental and Medical Sciences, Lucknow, Uttar Pradesh, India
4 Department of Orthodontics, Sardar Patel Post Graduate Institute of Dental and Medical Sciences, Lucknow, Uttar Pradesh, India
5 Department of Pediatric and Preventive Dentistry, Awadh Dental College, Jamshedpur, Jharkhand, India

Correspondence Address:
Prof. Sonu Acharya
Department of Pediatric and Preventive Dentistry, Institute of Dental Sciences, SOA (Deemed to be University), Bhubaneswar, Odisha
India

Abstract

Aims: Nanoparticles are being used a lot in dentistry, and the use of nanoparticles can bring about a change in almost all aspects of pediatric dentistry, from diagnosis to treatment. The aim here was to search scientific databases for the utilization of nanoparticles in pediatric dentistry. Nanotechnology is the science of material world in the scale of less than 100 nm. This has made a revolution in the field of medical and dental sciences by improvement in mechanical and physical traits of substances, helping to reinstate new investigative possibilities and microdelivery options. Materials and Methods: The literature search was done through various databases such as PubMed, Cochrane, Scopus, and Web of Science using MeSh and free terms to collect data on “nanoparticles in pediatric dentistry.” Those articles that are written in English and those that had full text available were considered since its use in dentistry, whereas unpublished data and literature written in other languages and articles with only abstracts were excluded. Following the search results obtained, 31 articles were relevant. The reference list of all the articles thus included was hand-searched; full text evaluation was done; and duplicates were removed. Results: The articles mentioning nanoparticles in pediatric dentistry were very few, so we included articles with some association with pediatric dentistry, and finally 21 articles met the criteria of search. Nanoparticles have tremendous potential for being used in pediatric dentistry, namely the prevention of dental caries, restorative materials, endodontics, and imaging. Although beneficial these materials have to be applied with caution as still no long-term studies are available. Conclusion: Nanotechnology has been exploited in dentistry mostly with beneficial results. Scientists are working very hard to incorporate nanoparticles into every aspect of dentistry, pediatric dentistry in particular. There is a dearth of studies, both in vivo and in vitro, on these materials, and more studies will substantiate the uses in pediatric dentistry. The present scientific review will help us in understanding nanomaterials and the advantages and demerits of nanotechnology by addressing its social and medical implications.



How to cite this article:
Acharya S, Godhi BS, Saha S, Singh B, Dinsa K, Bhagchandani J, Gautam A. Use of nanoparticles in pediatric dentistry: A narrative review.J Int Oral Health 2022;14:357-362


How to cite this URL:
Acharya S, Godhi BS, Saha S, Singh B, Dinsa K, Bhagchandani J, Gautam A. Use of nanoparticles in pediatric dentistry: A narrative review. J Int Oral Health [serial online] 2022 [cited 2022 Oct 5 ];14:357-362
Available from: https://www.jioh.org/text.asp?2022/14/4/357/355019


Full Text

 Introduction



Nanoparticles (NPs) are clumps of atoms with a varied scope of medicinal value including oncotherapy, medicinal distribution, tissue-engineering, biomolecules detection, and the use as antimicrobial agents.[1] NPs have been classified as organic, inorganic, and carbon-based. The initial protocols that have evolved in nanotechnology area were given by K. Eric Drexler from the Fore-sight Institute.[2] He delivered the lecture on intricacies of nanotechnology to the gathering through his publication titles, Engines of Creation. The most vital challenge for scholars in dentistry is to manufacture products and is able to withstand the harsher conditions inside mouth, where also maintaining biological sustainability and biocompatibility. NPs are getting popular in dentistry, because of their vast potential in biocompatibility, size, charge, surface area, color stability, and thermal conductivity. When compared with the similar product in comparison (big or small), NPs can be packed with ease in numerous packaging arrangements because of their high exterior to interior value, which can be easily manipulated and used in various methods of application.[3] In spite of all these favorable properties that make them an exciting prospect, they have disadvantages too like toxicity, limited delivery, and difficult handling.[4] The unpredictable nature of nanomaterials makes a moral conundrum for dentists when being challenged with a varied area of materials to try with, some of them showing very long historical backgrounds that reinforce their clinical use as composite resins and others such as the nanofilled composites those of which are exquisite in conception and also supported by randomized trials. The idea behind this work was to find out the use of NPs in pedodontics and the implications on future developments in this field on pediatric dentistry. The review here focuses on the use of NPs in pediatric dentistry, where not much has been done yet.

 Materials and Methods



We performed a thorough database search through the databases of PubMed/Medline, Scopus, Cochrane, and Web of Science, which dealt with NPs in pediatric dentistry. The search was conducted in the month of August onward with the MeSH and keywords:

Nanodentistry

NPs

Nanomaterials

Nanomedicine

Nanotechnology

Pediatric dentistry

Remineralization.

Eligibility criteria

For deciding the inclusion criteria, the PICOS guidelines were followed. The articles searched and included were:

All articles in English language

Full-text articles with abstract

Articles on the association of dentistry and NPs

Articles included since use of NPs in dentistry

Studies (in vitro and in vivo) that showed the use of NPs in preventive and restorative dentistry

Case series/report, articles in other languages than English, unpublished data, and irrelevant studies were not included. Dual publications also got rejected [Figure 1].{Figure 1}

Data were analyzed and compared with each individual paper in discussion, and possible outcomes were given. No statistical analysis was done on the extracted data.

 Results



Study recognition and preference

The starting electronic and hand search got 341 citations in PubMed, Scopus, Web of Science, and Cochrane database (2000–2021). After the initial screening and after the application of inclusion criteria, 42 articles were selected because of name, abstract, and complete text. At last, 21 reviews (narrative reviews, comprehensive reviews, and umbrella reviews) and clinical trials were selected that fulfilled the criteria.

Characteristics of included studies

Reviews, in vitro and in vivo studies, and randomized controlled trials were included.

Twenty-one papers that fulfilled the inclusion criteria were selected and included in our review. Those articles that discussed the role of NPs in pediatric dentistry were discussed.

Assessment and quality of proof in studies included

There is a consensus in the available literature in the studies (reviews and in vitro and in vivo) that the NPs have an enhanced antimicrobial and restorative reaction on various biomaterials and is a multifaceted stuff. Meta-analyses were nil on this material. The amount of clinical trials seems low on this too. There is an essentiality for future clinical studies to learn more about the effect in a long term of these NPs. In almost all the researches, ideal privacy procedure is utilized, and all applicable results are delineated in a standardized, validated, and dependable way.

 Discussion



Nanotechnology as a science has taken rapid strides into all fields of science as it provides alternate ways to resolve scientifically the medical queries and issues. Nanotechnology is a field of science that dwells on the proportions lesser than 100 nm.[5] Most of the works that have been carried out over the last 20–30 years seem to be associated with NPs, which tell very truthfully as to having so much interest in nanotechnology and the material properties at these amounts.

The use in dentistry has shown much potential in all branches of dentistry. The concept of nanotechnology has found a favor in pediatric dentistry too [Table 1]. Although not much research and systematic reviews are there, but still here, we discuss the use of nanotechnology in pediatric dentistry.{Table 1}

They can be used in pediatric dentistry in the following ways.

Dental caries

Dental cavities is one of the commonest oral diseases found in worldwide people, including children.[6] For the same reason, this is considered a public health scenario, and so it needs alternative treatment modalities to prevent caries. Dental cavities are caused by multiple factors and are mostly created by microbes-colonizing tooth surfaces and resultant formulation of biofilms. The microbes present orally promote sucrose breakdown, which generates acidic metabolites that very much reduce the oral pH. The acidity of pH initiates the demineralization of teeth, leading to the removal of ions (calcium and phosphorus) resulting in cavities.[12] This process can be reverted back with the use of fluorides, either alone, or can be incorporated in tooth pastes and mouth rinses.[13] Hydroxyapatite (HA) NPs can be used to revert the going away of enamel crystals as they are similar morphologically, crystalline, and similar chemical make-up (Ca10(PO4)6(OH)2).[14] HA NPs can be used as fillers to mend small depths on the enamel, as they create more surface for sticking, so they enable logging of the nanocrystallites. The use of NPs can help in this treatment of cavities. Intraoral drugs can be made in capsules; they can be dissolved or can stick to the organization of NPs; and this will be of use in dental applications,[15] e.g., NPs with good fluoride amounts can be put orally to increase the fluoride amounts. The use of NPs will allow the remineralization of the demineralized teeth and avoid the procedure of cavity formation. A calcium fluoride NP (CaF2NPs) is frequently used to increase the amount of fluorides available orally. CaF2NPs can inhibit the produce of exopolysaccharide by Streptococcus mutans.[16] The NPs have a double effect: the promotion of the remineralization of enamel and prevention of biofilm formation. However, the residual timing orally of CaF2NPs is short, and in order to have an improvement in this characteristic, the CaF2NPs can be attached to chitosan bioadhesive films. Another method for dental cavities therapy is the use of materials with biologically active functions.[17] Adding up of chitosan NPs in a Glass Ionomer Cement (GIC) is one of the ideas. Chitosan NPs are being used in dentistry as hydrogels and nanofibers for application orally.[18] Other polymeric NPs composed of poly(ethylene glycol) and polylactic-co-glycolic acid are used for the prevention and treatment of dental caries.[19] These polymers show mucoadhesion, biocompatibility, and biodegradability and are suitable for promoting the prolonged release. A NP-consisting solution that is used for the treatment of anemia significantly reduces the buildup of dental plaque and suppresses cavities as stated in a study. This is the first human trial to show the NPs’ healing potential for caries.[20] Ferumoxytol iron oxide NPs (FerIONP), a formulation agreed on by the Food and Drug Administration (FDA) for the treatment of anemia, and hydrogen peroxide (H2O2), were used in a human disease model; the combination showed potent antimicrobial properties against one of the most common bacterial pathogens in biofilms, Streptococcus mutans.[21] Additionally, the ferumoxytol-hydrogen peroxide treatment did not affect other bacteria found in the mouth. None of the complications or events was associated with this therapy. For caries detection, NPs that are made available from fluorescein-labeled eatable starch have been made, which gleam when lightened by a standard dental cure light and then get degraded into neutral compounds. Newer antibacterial resin-based sealants that include NPs of amorphous calcium phosphate for PO4 and Ca ion-released and recharged have been evaluated.[22] One of the most efficient approaches to remineralize the enamel is finding and developing analogues of natural proteins, including amelogenin engaged in biomineralization via natural macromolecular polymers and imitation of the biomineralization process.[23] This can be used as a future procedure in managing initial caries in a minimal invasive way. ZrO2 NPs have been in suggestion for being applied in dental care and related biomedical uses for future research.[24]

Stronger restoratives

NPs most poised to be used in pediatric dentistry are to create stronger and more flexible restorative materials. Composites with silica and silicon dioxide NPs are stronger and flexible than traditional composites.[25] Glass incomers with NPs are more biocompatible and show a better adherence to dentine. The first resin-modified GIC, built on nanofill technology, is Ketac N-100.[26] This cement represents a union of fluoroaluminosilicate and nanotechnology concepts.[27] Fuji IX GP is a dental nanomaterial that behaves as human dentin and contains next-generation glass filler, namely SmartGlass. The important characteristic of this restorative nanomaterial is its translucent nature, the property of fluoride release, reactivity, and faster setting time.[28] Nanotechnology for the evolution of bioactive substances in dentistry has been evolving for many years. Several newer approaches, such as metal-based NPs with antibacterial property and calcium phosphate-based nanotechnology for the balance of demineralization, have provided potential benefits for restorative dentistry.[29] The basis of therapeutic achievement that is in association with NPs is dependent mainly on the properties of these NPs, e.g., their surface area, chemical activity, and biological reactivity.

Clear imaging

NPs do not just have direct effects on the oral environment; they can also be used to enhance dental imaging. This is because some types of NPs coat dental surfaces, contrasting teeth, and gums from other structures in radiographs and images.[30]

Remineralization

HA NPs with silica and silicon dioxide NPs helped restore demineralized dentin up to 20% of the dentin’s original phosphate levels. An increase in the remineralization of both dentin and enamel was seen with toothpastes having HA particles compared with fluoride amine toothpastes.[31] Owing to their colloid size of particle and the potential transportation of calcium ions, calcium carbonate (CC) nanostructures can be retained well on oral tissues. These act like transportation vehicle for slowly releasing a high amount of calcium ions into the adjacent oral fluids. These particles also have the potential to raise the surrounding fluid pH. Therefore, CC NPs were also efficient in the remineralization of starting lesions when being conglomerated into an experimental tooth paste.[32]

Pulp and periapical lesions

Pulpal exposure is a challenge to treat even if the cause is known. The main goal of endodontic is to remove any microbial infection and help in periapical tissue healing. This branch can have benefits from the evolution of nanotechnology because of its wide antigerm and biofilm reactivity and biocompatibility. Chitosan has widespread use in endodontology.[33] This may be used with success as a chelate, as well as a scaffolding agent for the delivering growth factors, or drugs. Silver NPs, singularly or in combination with other agents, have a good effect against E. faecalis, have good biocompatibility, have lower cytotoxicity, and can be used as an irrigating solution, sealer, and chelating compound.[34] In comparison to the usual sodium hypochlorite solution (5.25%), magnesium oxide NPs (5 mg/L) showed a significant long-term effect statistically in the eradication of E. faecalis adhering to dentin of the root canals. Pulp regeneration can be done with the help of nanotechnology.[35] The α-melanocyte-stimulating hormone (α-MSH) is said to be having anti-inflammatory properties. It has also been found that NPs containing α-MSH has tissue revitalizing action. The applications based on nanotechnology in endodontology include the incorporation of bioceramic particle in endodontic sealers, which can be in the form of bioglass, zirconia, etc. This has also been seen that the use of NPs can enhance the adhesiveness to smaller irregularities; it also has faster setting times when compared with conventional sealers; it is dimensionally stable, insoluble in tissue fluid, chemically bonds to tooth tissue, and osseoconductive.[36]

Toxicity of nanoparticles

It can be said that NPs can have a big role in future, but the sustainability of these materials cannot be predicted. The incorporation on NPs can make materials environment-friendly, healthy, and safer than the traditional materials in use. NPs may be getting released as a puff of dust in the laboratories in dentistry. Stringent legal mandates in occupational safety are there in place for different countries (e.g., Occupational Safety and Health Administration, OSHA). NPs may go inside the organisms due to ingestion or inhalation and get to different organs and system that can have a damaging effect on them.[37] One of the potential routes of NP toxicity is its ability to organize around protein molecule. As a result of such binding, they can cause biological destruction. One other mode of destruction is the generation of poisonous ions.[38] In all cases, the amount of dust coming out should be kept minimal by judiciously sculpturing the restoration. Using water spray to cool and the use of effective suction whenever possible, during the grinding and polishing inside the oral cavity, is a recommendation. Efficient ventilation in place of treatment is to be followed as well as the use of capsules of powder/liquid systems. Protective metrics, as defined by use of an appropriate mask, might limit the exposure of dental professionals to the dust of NPs. A trial done by the Karolinska Institute in Sweden found that iron-oxide NPs were not toxic to human lung epithelial cells and cause no damage to deoxyribonucleic acid (DNA). Zinc-oxide NPs were little bad too. Titanium dioxide destroyed the DNA only; carbon nanotubes caused DNA destruction at lower levels. Copper oxide too was revealed as having higher toxicity and was categorized as a health hazard.[39]

 Conclusion



Pediatric dentistry has evolved a lot over the time. The discovery and invention of newer materials and technologies for the eradication of dental problems has been the foremost issue of doctors and scientists associated with this field. The usage of NPs is an appropriate strategy that can help in the prevention, shortening of the treatment duration, or eradication of oral issues such as dental caries and can be incorporated in materials such as glass ionomer cement and composite resins. The above-mentioned list is made to be of relevance for future endeavors in dental nanomaterials technology, and also there will be more work in the area of pediatric dentistry. The use of antimicrobials as innovative nanocoatings can be of use in pediatric restorative dentistry. Nanotechnology is foreseen as a change in healthcare fundamentals. More studies, especially clinical trials and systematic reviews, need to be conducted on these nanomaterials, but till then these materials promise to be the future of pediatric dentistry.

Acknowledgement

Nil.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Authors’ contributions

SA conceived the idea and study design. BG, SA, and SS performed the literature search. JB and KD performed the extraction of data. BS drafted the article. SA and AG reviewed the article.

Ethical policy and institutional review board statement

Not applicable.

Patient declaration of consent

Not applicable.

Data availability statement

Not applicable.

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