Skip to main content

Influence of inorganic nanoparticles on dental materials’ mechanical properties. A narrative review

Abstract

Inorganic nanoparticles have been widely incorporated in conventional dental materials to help in improving their properties. The literature has shown that incorporating nanoparticles in dental materials in different specialties could have a positive effect on reinforcing the mechanical properties of those materials; however, there was no consensus on the effectiveness of using nanoparticles in enhancing the mechanical properties of dental materials, due to the variety of the properties of nanoparticles itself and their effect on the mechanical properties. This article attempted to analytically review all the studies that assessed the effect of different types of inorganic nanoparticles on the most commonly used dental materials in dental specialties such as polymethyl methacrylate, glass ionomer cement, resin composite, resin adhesive, orthodontic adhesive, and endodontic sealer. The results had shown that those inorganic nanoparticles demonstrated positive potential in improving those mechanical properties in most of the dental materials studied. That potential was attributed to the ultra-small sizes and unique physical and chemical qualities that those inorganic nanoparticles possess, together with the significant surface area to volume ratio. It was concluded from this comprehensive analysis that while a definitive recommendation cannot be provided due to the variety of nanoparticle types, shapes, and incorporated dental material, the consensus suggests using nanoparticles in low concentrations less than 1% by weight along with a silane coupling agent to minimize agglomeration issues and benefit from their properties.

Peer Review reports

Introduction

Human tooth tissues are comprised of diversified micro nanostructures. For example, carbonated hydroxyapatite, with a range of 10–200 nm in size, is made up of 96% of enamel structure [1]. Dentin nanostructures are also unique, with intertubular dentin being 60 nm long and 2–5 nm thick. Peritubular dentin nanostructures are roughly 25 nm long and 2–5 nm thick, and dentine collagen fibrils range in size from 20 to 75 nm [1, 2].

Nanotechnology is essentially a science and engineering of functional systems at a nanoscale (one-billionth of a meter) [3,4,5,6]. Accordingly, when a material is smaller than 100 nm in one dimension, it is defined as a nanomaterial [3,4,5, 7, 8]. Hence, the aim of nanotechnology in dentistry is to mimic the natural tissue architecture, both soft and hard, by adapting new dental biomaterials to achieve better restoration of lost tissue that occurs due to disease, and to provide antimicrobial activity where necessary [1].

Nanomaterials can be synthesized in a variety of ways depending on a multitude of factors, such as the dimension of the materials being created. Hu and Shaw categorized nanoparticles as zero-dimensional, one-dimensional, two-dimensional, and three-dimensional [9]. Zero-dimensional nanoparticles (NPs) are defined as the nanostructure that has all dimensions in the nano-range, and they are amongst the most commonly employed type of nanomaterials in dentistry [9].

The main characteristic of NPs is that they have a very potent antimicrobial action against bacterial biofilm [10]. As NPs have a high surface area and high charge density, the nanoparticle ions in contact with microorganisms produce a germicidal effect [10,11,12,13]. They can also fill the gaps between the inter-polymeric chains, resulting in augmented mechanical and physical strength [14].

Different types of NPs have different properties. There are two main types of NPs: organic and inorganic. Quaternary ammonium polyethyleneimine (QPEI) [15], quaternary ammonium dimethacrylate [16], dimethylaminohexadecyl methacrylate [17] and chitosan [18, 19] are examples of organic NPs. Metal and metal oxides are examples of inorganic NPs.

Meanwhile, polyhedral oligomeric silsesquioxane (POSS) is an example of a nanosized organic-inorganic hybrid material consisting of a Si-O bond in three-dimensional architecture that is used with dental nanocomposites [20, 21].

Studies have shown that both organic and inorganic NPs have antimicrobial properties. The mechanical and physical properties have been more extensively studied with inorganic NPs, whereas there is limited data on the mechanical and physical properties of organic NPs. Similar to NPs, the large surface to volume ratio of nanomaterials is one of their most notable characteristics [7]. When considering a nanoparticle with a diameter of a few nm, all the atoms are either at the nanoparticle’s surface or inside the particle within a few atomic distances from the surface, depending on the atoms’ size and the nanoparticle’s size [7]. All atoms in a bulk material bind to their neighbors. Surface atoms, on the other hand, have fewer near neighbors, resulting in hanging or unsatisfied bonds, which results in an extra energy called surface energy, surface free energy, or surface tension that has a significant impact on the particle’s physical properties [16]. The above-mentioned physical and chemical phenomena have a number of significant implications for the characteristics of nanoscale materials and their manufacturing. In order to lower their surface energy, NPs try to agglomerate, resulting in the loss of its optical properties [4, 5, 7, 22]. It also loses some of its effective characteristics like the antimicrobial action, or it can leave inter-polymeric chain spaces unfilled, reducing the unique mechanical features. For this reason, good dispersion of NPs in the matrix is considered the main key for an effective nanomaterial. Similarly, the biological safety of nanoparticles is a critical aspect, as it depends on several factors such as their shape, size, method of preparation, and the chemicals used [23].

Recently, NPs are purposefully embedded in dental products to improve the material’s qualities as well as improve its longevity and success rate [3, 24]. Such fillers can be found in a variety of dental materials, including resin-based composites, cements, and impression materials [8, 12, 13] for the treatment of common dental diseases such as caries and periodontal infections [1, 25, 26]. As patient treatment needs, both esthetic and function, continue to expand, today’s scientists and engineers need to diversify nanoscale materials to take advantage of their superior features [1, 27].

Many studies and reviews focus on the antimicrobial properties of NPs-reinforced materials and demonstrated that NPs possess superior antimicrobial activity compared to their regular sized counterparts [10,11,12,13, 16, 28,29,30,31,32,33,34,35,36,37,38,39,40,41]. On the other hand, the studies that evaluate the physical properties of NPs are limited and the results presented are conflicted [42,43,44]. Inorganic nanoparticles incorporated into dental materials have been evaluated for their potential benefits, but the body of literature that focuses on the mechanical properties and their importance specifically to dental materials is lacking. In response to this, we sought to provide a comprehensive analytical review on how inorganic NPs influence the mechanical properties of dental materials in a variety of dental applications including prosthodontics, orthodontics, restorative dentistry, and endodontics.

Methodology

In order to achieve a conclusive result regarding the effectiveness of NPs on the mechanical properties of different dental materials, three databases (PubMed, Web of Science and Scopus) were searched during the time period from January 2021 to December 2021 using the association of the keywords: ‘inorganic nanoparticles,’ ‘dentistry’ and ‘mechanical properties’. The Boolean operators for each database were written as [“inorganic nanoparticles” AND “dentistry” AND “mechanical properties”]. For an article to be considered for inclusion in the review, it had to be written in English, and performed as a laboratory study or on humans (in vivo or in vitro on human cells). Furthermore, the papers had to be done on materials that were reinforced by NPs, and the test must have involved the evaluation of the mechanical properties of these NPs-reinforced materials.

The initial search in PubMed, Web of Science and Scopus databases conducted by the keywords revealed a total of 367 articles (Fig. 1). The screened data resulted in 133 duplicated articles. 234 articles remained to be subjected to title and abstract analysis. The eligibility criteria involved original articles in the English language related to NPs incorporated with conventional dental materials and the measurement of the mechanical properties. Review articles were excluded. This resulted in 63 articles of which 13 were excluded after reading the full text. Finally, full texts of 50 articles were included in the review.

Fig. 1
figure 1

Visual diagram of article filtration and selection from the PubMed, Web of Science, and Scopus databases

Results

The total number of full-text articles included in this review is 50 articles. All tables show results of different parameters including author and year of the publication, sample size, NPs used in the dental material, size, concentration, the type of dental material, treatment groups, type of mechanical test, and outcome/result findings. Tables 1, 2, 3, 4 and 5, and 6 show results for the review of the materials: polymethyl methacrylate, glass ionomer cement, resin composite, resin adhesive, orthodontic adhesive, and endodontic sealer, respectively.

Table 1 Mechanical properties of PMMA reinforced by different NPs.
Table 2 Mechanical properties of Glass Ionomer Cement reinforced by different NPs.
Table 3 Mechanical properties of Resin composite reinforced by different NPs.
Table 4 Mechanical properties of resin adhesive reinforced by different NPs.
Table 5 Mechanical properties of orthodontic adhesive reinforced by different NPs.
Table 6 Mechanical properties of endodontic sealer reinforced by different NPs.
Fig. 2
figure 2

Diagram of the distribution of articles by the dental material and type of nanoparticle

The total number of articles included in this review is 50 articles as shown in Fig. 2. The most common material that was investigated by researchers was PMMA with a total of 21 studies, followed by glass ionomer cement (GIC), resin composite, resin adhesive, and orthodontic adhesive with a total of 14, 6, 5 and 2 studies, respectively. The least investigated material was endodontic sealer with two articles. The most commonly used NPs used in all the studies were SiO2, TiO2, and ZrO2.

DISCUSSION

All 50 reviewed studies were in-vitro bench studies that used inorganic NPs as enforcing fillers in different dental materials to improve their mechanical properties. Their main objective was focused on enhancing the mechanical properties of some of the widely used conventional dental materials as those materials possessed some limitations. In order to improve those mechanical properties, the researchers resorted to using inorganic NPs as fillers. The studies then assessed the different mechanical properties of those NPs-incorporated dental materials with different concentrations of the inorganic NPs in an attempt to formulate a hybrid material with superior mechanical properties to the conventional one. However, the most challenging factor that these studies faced when incorporating the NPs with the dental materials is the tendency of NPs to agglomerate. This is a serious problem that can lead to a reduction of the nanoparticles’ surface energy, resulting in a loss and change of their nano-properties [7]. For that reason, and to achieve an appropriate homogeneous dispersion, all researchers used the NPs only with low levels of concentrations as it aided to minimize or eliminate the NPs agglomeration. In addition, some researchers found that using a silane coupling agent with the NPs was highly effective in avoiding that issue [45, 54, 56, 62, 77, 92]. The outcome of the mechanical properties of the modified dental materials reviewed in this study varied from one material to another, and from one mechanical testing to the other, based on the type and concentration of the NPs used, together with the original inherit composition and characteristics of the materials themselves.

Polymethyl methacrylate (PMMA)

PMMA-based resins are widely utilized in dentistry for a variety of applications, including removable base plates, functional appliances, and denture bases [93]. Its benefits stem from its biocompatibility and esthetics [81, 94]. It is also simple to manufacture, inexpensive, and has specific characteristics such as low weight, low water sorption, and low solubility [45, 95]. The material’s weakness involves the limited mechanical strength of PMMA resin denture base materials, with low impact and flexural strengths [94, 96, 97]. As a result, denture failure occurs frequently when eating or falling [98]. For these reasons, PMMA was the top material on the list of most studies (21 studies) that used NPs as a reinforcing filler to strengthen the PMMA’s mechanical properties. The reinforcing agent’s chemical bond with the polymer matrix was strong enough to withstand and transmit occlusal forces from the weaker polymer to the stronger reinforcing agent [51, 52, 55, 56, 59,60,61]. Additionally, the consistent impregnation of the reinforcing agent in the matrix inhibits the formation of stress concentrators [50, 51, 55, 56, 61] which could compromise the resins’ mechanical qualities.

The most commonly used NPs as fillers to reinforce PMMA were SiO2 and ZrO2 (7 studies each). The purpose for selection of those two NPs was due to their inherent properties that can enhance acrylic resins’ mechanical characteristics [50, 52, 54]. They possess a number of desirable features, including high toughness, mechanical strength, abrasion and corrosion resistance, and biocompatibility [99, 100]. Additionally, ZrO2 has excellent mechanical qualities that allow it to resist crack propagation, and it is noted to hold the greatest hardness of any oxide [101, 102]. The flexure strength, tensile strength, impact strength, fracture toughness and the surface hardness of PMMA reinforced by 0.5 to 1 wt% of ZrO2 or SiO2 increased significantly [45, 46, 49, 50, 52]. Surface treated ZrO2 or SiO2 with a silane coupling agent led to a decrease in the surface tension of the particles and influenced the spatial distribution of fillers, resulting in higher mechanical properties than with untreated NPs [51, 56, 92].

Conversely, one study concluded that using SiO2 incorporated with PMMA led to a significant decrease in the flexure strength of the original material. However, while further examining their technique, it was found that they incorporated the NPs in the monomer liquid and that they mixed it manually. That approach can cause uneven distribution and dispersion of the NPs within the matrix, which was confirmed by their SEM analysis that detected porosity in the PMMA matrix [47].

Although there is less published work on using Al2O3, TiO2 and diamond NPs fillers with PMMA compared to ZrO2 and SiO2, the results of those studies showed similar significant increase in the flexure strength, impact strength, and surface hardness [48,49,50, 60, 61]. However, due to the variability of the NPs, more studies with those NPs are needed to verify and validate those results.

Using Ag NPs did not appear to improve the mechanical properties of PMMA [57, 58, 103]. Ag NPs is mainly used for their antimicrobial activity to treat common infections of oral mucosal tissues in complete denture users [104]. They have been demonstrated to be effective against many microorganisms such as E. coli, Staphylococcus aureus, Staphylococcus epidermidis, Candida albicans, and Streptococcus mutans [105,106,107]. However, a significant increase in the flexure strength of PMMA was found when it was modified with graphene-Ag NPs [59] Additionally, adding Au NPs to PMMA showed no significant decrease in the flexure strength of the material; however, a significant increase in the micro hardness of the PMMA was observed when 0.43 wt% Au was added [63]. Similar results regarding the flexure strength was observed when ZnO was incorporated with PMMA [62].

The overall results of those studies indicated that most NPs proved to have a positive significant effect in improving the different mechanical properties of PMMA, especially when used in low concentrations of 0.5%.

Glass ionomer cement (GIC)

Biological compatibility, adhesion to moist tooth structure that allows for little removal of sound tooth structure, and anticariogenic qualities due to fluoride release are just a few of the benefits of GIC. Furthermore, it has a coefficient of thermal expansion that is similar to that of tooth structure. Despite those advantages, conventional glass ionomer cements possess limitations as restorative materials due to their brittleness, low flexural strength, low fracture toughness, low wear resistance, slow setting rate, high solubility and the relatively high sensitivity to water at the initial stage of setting [106, 107]. Numerous modifications had been developed over the years in attempt to overcome these drawbacks and improve the mechanical properties [108]. Most recently, NPs have been incorporated into glass ionomers with the objective of enhancing their mechanical strength. GIC was the second in list of number of studies (14 studies) that used NPs to augment its properties.

TiO2 was the top NPs selection used for GIC. Because of the relatively smaller size of TiO2 NPs supplemented into the glass powders, they can fill in the voids between the bigger GIC glass particles and serve as extra polyacrylic polymer bonding sites [35, 64,65,66,67,68,69]. For this reason, the flexure strength, compressive strength, and hardness value increased significantly by incorporation of 3, 5 and 7 wt% TiO2 [64,65,66,67,68,69]. Moreover, the compressive strength of GIC reinforced with 2 and 10 wt% ZrO2 also increased, while the addition of Al2O3 showed no effect on the mechanical properties [68, 69].

Together with the exceptional antimicrobial properties of Ag NPs, the incorporation of Ag to GIC showed a significant increase in the hardness, flexure strength, compressive strength, and shear bond strength [70,71,72]. The concentrations of 0.1–0.5 wt% were the most optimum concentrations for increasing those mentioned properties. At that very low level of concentration, the voids in the GIC matrix were filled with the small size of Ag nanoparticle fillers [35, 68, 70,71,72, 109]. Filling those voids resulted in the improved packing of particles within the matrix, which ultimately led to the enhancement of those mechanical properties.

Enforcing GIC with hydroxyapatite (HA) and fluorapatite (FA) NPs were evaluated in other studies [73, 74]. HA has a comparable composition and structure to enamel and dentin [109,110,111], which gives it the advantage and the edge to enhance the shear-bond strength with tooth structure. Furthermore, compressive strength, diametral tensile strength, and microhardness had all been significantly improved [73, 74] Alternatively, FA showed better results than HA due to its higher crystallinity [111, 112].

A combination of HA and SiO2 have been successfully used to enhance GICs [113]. Moreover, ZrO2 or a combination of HA and ZrO2 had been incorporated in attempts to strengthen GIC with improved outcomes [114, 115]. Zirconium and its oxide, due to their good dimensional stability and toughness, have been widely used for the toughening and strengthening of brittle HA bio-glasses in biomedical applications [116]. Because of that, using 5 or 7 wt% of ZrO2-SiO2-HA with GIC resulted in a significant improvement in the mechanical properties.

The crystalline structure of forsterite NPs resulted in the production of crystalline phases in the amorphous cement matrix [109, 117]. This could justify the enhancement of the flexure strength, compressive strength, and tensile strength of GIC reinforced with 1 wt% Mg2SiO4 [75].

Incorporation of MgO nanoparticles into different dental products was done to imbue antimicrobial properties [76, 118,119,120]. Regarding its mechanical effect on the GIC, the results showed a significant increase in the compressive strength and diametral tensile strength values when MgO was used at 1 wt% [77].

In general, GIC’s limited mechanical properties were improved when modified with different NPs in all the in-vitro studies reviewed. A low concentration of 0.1-1% of different NPs was found to give the most optimum results. Furthermore, comparable composition and structure of NPs to those of enamel and dentin significantly improved the GIC’s different mechanical properties, particularly the ones with higher crystallinity.

Resin composite

Resin-based composites are currently one of the most popular dental restorative materials due to their superior esthetic features and good adhesive properties [121,122,123]. However, resin composites have a number of mechanical shortcomings, including wear resistance, hardness, and shrinkage tendency [121, 124]. Secondary caries continues to be the most common cause of dental restorations’ service life being shortened, ultimately necessitating restorative material replacement. In terms of improving the features of resin composites, there are a few solutions that could be achieved. Dental resin nanocomposites are one of them; they are made up of a resin matrix, nanofillers, photo-initiator, and other components that are integrated together.

Regarding the benefits and drawbacks of nanocomposites, manufacturers rarely disclose the accurate proportional quantity, geometry, and size of nanofiller, which can be troublesome when these are important factors in determining the outcome of the mechanical properties. Furthermore, mostly all restorative “nanocomposites” are “nano-hybrids” with substantially larger volume ratios of non-nano sub-micron or micron-sized particles [7]. The other way in order to improve the mechanical properties of conventional resin composite is to use NPs [77,78,79,80,81,82,83]. NPs with nano-scale dimensions allow a wider area of interactions with microorganisms, thereby increasing their antibacterial activities, which is a requisite for dental restorative materials to prevent secondary caries [79, 80, 125]. Most of the studies involving the addition of NPs to dental composite resins mainly focused on their anti-bacterial effects, while the information regarding their mechanical properties was limited.

The mechanical properties, radiopacity, and optical properties of conventional composite resins have been improved by addition of inorganic NPs such as ZnO and TiO2 [77,78,79,80,81]. TiO2 offers a wide range of positive features. It is nontoxic, chemically stable, and has high photocatalytic efficiency [77]. In addition, TiO2 NPs are tooth colored and does not stain the restoration [78, 126]. The presumably smaller size of theTiO2 NPs promotes close cross-linking to the resin particles and prevents their degradation [79, 127]. Using 1 wt% TiO2 with dental resin composite leads to a significant increase in the flexure strength and surface hardness [78, 79]. These results increased specifically when the NPs were treated with a silane coupling agent, improving the dispersal and bonding of the filler particles throughout the matrix [78]. Additionally, the supplementation of Fa-HNT based fillers at low concentrations in dental composites was found to greatly improve the mechanical properties [82].

ZnO showed no effect on the flexure strength, but had a significant effect on the compressive strength and flexure modulus at 1 wt% concentration [80]. Combining ZnO with CaF2 showed a significant increase in the flexure strength at 0.5 wt% [81]. The opacity of ZnO NPs against visible light may have had a negative impact on light curing and, as a result, the mechanical characteristics of composites [80, 81, 86]. Because of that, further increase in the concentration of NPs led to decrease in the mechanical properties. It is possible to deduce that the decrease in mechanical characteristics was more likely a result of the effect of the NPs on composite curing rather than the occurrence of structural defects owing to particle agglomeration.

Despite the few number of studies that assessed the effect of enhancing composite resin with NPs (6 studies), their outcome was in favor of the positive added value of NPs in improving the tested mechanical properties of resin composite.

Resin adhesive

Dental adhesives have become commonly employed in restorative dentistry due to their esthetic and conservative characteristics. In reality, the clinical efficacy of resin composite is influenced by the restorative materials’ full adherence to enamel and dentin [95]. The acid-etch process is frequently successful when it comes to enamel [128, 129]. Dentin, on the other hand, is a hydrated biological composite made up of inorganic compounds, organic compounds, and water, with capabilities that vary greatly depending on where it is found. Furthermore, dentin has fluid-filled dentinal tubules, which create a dynamic and wet surface for bonding chemicals, as well as a more difficult situation than enamel [130, 131]. NPs have recently been introduced into dental adhesives with the goal of increasing mechanical qualities [132, 133]. Filler particles are used in dental adhesives to strengthen the bond between the adhesive and the dentin by entering the tubules of the dentin, reducing polymerization shrinkage, and raising the elastic modulus of the adhesive layer. [134]

Adding HA NPs to dental adhesives showed an increase in the micro-shear bond strength, tensile and flexure strengths [86]. Moreover, using Cu NPs demonstrated a better shear bond strength than conventional resin [83,84,85]. When compared to Cu free adhesives, these adhesives formed interfaces capable of reducing the deterioration of resin–dentin bonded surfaces [134]. Furthermore, since the collagen crosslinking enzyme Lysyl oxidase (LOX) is Cu dependent, Cu NPs had an indirect effect as a crosslinking agent, which consequently increased the strength of the collagen network, one of the components of the hybrid layer. Copper’s activity as a cross-linker may help collagen become more resistant [135, 136]. Using Ag NPs did not give any significant results on the mechanical properties of dental resin adhesive [87].

Orthodontic adhesive resin

Failure of the orthodontic bracket bonding method results in frequent debonding of the brackets, delaying treatment results. The bonding mechanisms and the failure rates of orthodontic brackets might be affected by tooth or material-related variables [136]. Previous studies have concentrated on the pre-treatment of resin monomers [137], inorganic fillers, and the development of curing procedures to improve the properties of orthodontic resin adhesives [110, 125, 138,139,140]. In dental adhesives, NPs have been explored as strengthening fillers—adding these NPs will result in an increase of the adhesive’s mechanical properties [88, 89, 137, 141]. Using Cu NPs with the orthodontic adhesive resulted in a significant increase in the shear bond strength [88]. Mixing of ZrO2 with TiO2 showed a significant increase in the shear bond strength, compressive strength, and tensile strength of the orthodontic adhesive [89].

Endodontic sealer

The physicochemical and biological features of the newly proposed root canal filler materials should be investigated. Setting time, flow, film thickness, solubility, radiopacity, dimensional stability, and compressive strength of endodontic sealers are among the criteria evaluated by the American National Institute/American Dental Association and the International Organization for Standardization [142, 143]. Combining ZrO2 with NbO NPs showed a significant increase in the compressive strength in Portland sealer compared to MTA Fillapex and Sealapex. However, the compressive strength of AH Plus sealer was significantly higher than reinforced Portland cement [90]. Using QPEI NPs with AH Plus and Pulp Canal Sealer resulted in no significant difference in the mechanical properties between all experimental groups [91]. Nonetheless, due to lack of sufficient studies on measuring the mechanical properties of sealer materials reinforced with NPs, we cannot give a conclusive statement about using NPs in different endodontic sealers.

Analysis of NPs used

The incorporation of NPs into different dental materials was utilized as a positive means of increasing their mechanical properties. TiO2 NPs offered flexure strength, impact strength, and surface hardness when incorporated into PMMA, higher flexure and compressive strengths with GIC, and enhanced the flexure strength and the surface hardness of the resin composite. ZrO2 and SiO2 offered better flexure strength, tensile strength, impact strength and surface hardness properties when incorporated into PMMA and enhanced the flexure strength and compressive strength of GIC. The shear bond strength of Cu nanoparticle-modified dental adhesive material was significantly higher when compared with the original material. The improvement in the mechanical properties of different dental materials that included NPs occurred due to several reasons: these NPs filled the empty voids within the matrix of the original materials, which improved their strength. Furthermore, the large interfacial area of NPs provided more contact points with the materials, and also interrupted crack propagation by transferring stresses from the weak original material to the strong NPs filler. Additionally, using silane-coupling agent created a strong adhesion between the original material matrix and the NPs. Regarding resin composite materials, the small size of NPs promoted cross-linking to the resin particles. Using NPs with adhesive resin improved the mechanical properties due to an increase in the strength of the collagen network.

All of the reviewed studies dealing with NPs-reinforced dental materials were in-vitro studies. Many of the studies operated on the basis that the use of various inorganic metal oxide NPs has the potential to be an innovative solution to improve those materials’ weaknesses. Despite the great potential that their promising results revealed for the effectiveness of incorporating NPs in different dental materials, unfortunately those bench studies were not followed up yet with clinical trials that could support those findings. Currently, there are very few studies that performed in-vivo testing in that context. Hence, those in-vitro results cannot be generalized to the real clinical settings without the confirmation of many and different in-vivo studies. NPs can be a great contemporary addition that could provide those dental materials tested with superior properties compared to those of the original ones. They can provide those enhanced materials with longevity and a higher success rate, and consequently augment their quality along with enhancing the quality of life of the patients using them. Therefore, well-designed clinical trials are essential to confirm the results of the published in-vitro claims and to encourage manufacturers to include NPs as a standard ingredient in the composition of those materials.

Summary

Several of the in-vitro studies demonstrated that the incorporation of NPs within various dental materials revealed very promising significant results in improving the different mechanical properties of the original material. Nonetheless, due to the variety of the nanoparticles, it is challenging to identify the optimum specifications that suit the spectrum of dental materials. Generally, the studies used NPs in low concentrations less than 1% by weight along with a silane coupling agent to minimize agglomeration issues; however, further clinical trials can validate the claimed positive results and confirm the performance and long-term effectiveness of those new hybrid nano materials in real clinical settings.

Data Availability

Data is available from the corresponding author upon reasonable request.

Code Availability

Code sharing is not applicable to this article as no code was generated or analyzed during the current study.

Abbreviations

NPs:

Nanoparticles

PMMA:

Polymethyl methacrylate

HA:

Hydroxyapatite

FA:

Fluorapatite

GIC:

Glass ionomer cement

QPEI:

Quaternary ammonium polyethyleneimine

References

  1. Pokrowiecki R, Pałka K, Mielczarek A. Nanomaterials in dentistry: a cornerstone or a black box? Nanomedicine. 2018;13(6):639–67.

    Article  PubMed  Google Scholar 

  2. Goldberg M, Kulkarni AB, Young M, Boskey A. Dentin: structure, composition and mineralization: the role of dentin ECM in dentin formation and mineralization. Front Biosci. 2011;3:711.

    Article  Google Scholar 

  3. Elkassas D, Arafa A. The innovative applications of therapeutic nanostructures in dentistry. Nanomed Nanotechnol Biol Med. 2017;13(4):1543–62.

    Article  Google Scholar 

  4. Schmalz G, Hickel R, van Landuyt KL, Reichl F-X. Nanoparticles in dentistry. Dent Mater. 2017;33(11):1298–314.

    Article  PubMed  Google Scholar 

  5. I.T. 10993-22., Biological evaluation of medical devices—part 22: guidance on nanomaterials. International Organization for Standardization., (2016).

  6. R. P., Nanoelectronics: single file. Nat Nanotechnol (2006).

  7. Jandt KD, Watts DC. Nanotechnology in dentistry: Present and future perspectives on dental nanomaterials. Dent Mater. 2020;36(11):1365–78.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Vollath D. Nanoparticles-nanocomposites–nanomaterials: an introduction for beginners. John Wiley & Sons; 2013.

  9. Hu SD. Synthesis and assembly. In: Siegel R, Hu E, Roco MC, editors. Nanostructure Science and Technology. 1st ed. Boston: Kluwer Academic Publishers; 1999. pp. 15–33.

    Chapter  Google Scholar 

  10. Song W, Ge S. Application of antimicrobial nanoparticles in dentistry. Molecules. 2019;24(6):1033.

    Article  PubMed  PubMed Central  Google Scholar 

  11. Saafan A, Zaazou MH, Sallam MK, Mosallam O, El HA, Danaf. Assessment of photodynamic therapy and nanoparticles effects on caries models. Open Access Macedonian Journal of Medical Sciences. 2018;6(7):1289.

    Article  PubMed  PubMed Central  Google Scholar 

  12. Ana-Paula-Rodrigues F-C, Magalhães L, Moreira C-R, Denise-Ramos-Silveira Alves A, Estrela C, Estrela M-S, Carrião A-F, Bakuzis L-G, Lopes. Silver nanoparticles in resin luting cements: Antibacterial and physiochemical properties. J Clin Experimental Dentistry. 2016;8(4):e415.

    Google Scholar 

  13. Cao WZ. Novel resin-based dental material with anti-biofilm activity and improved mechanical property by incorporating hydrophilic cationic copolymer functionalized nanodiamond. J Mater Sci Mater Med. 2018;29:162.

    Article  PubMed  Google Scholar 

  14. Amin F, Rahman S, Khurshid Z, Zafar MS, Sefat F, Kumar N. Effect of nanostructures on the properties of glass ionomer dental restoratives/cements: a comprehensive narrative review. Materials. 2021;14(21):6260.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Pietrokovski YN. Antibacterial effect of composite resin foundation material incorporating quaternary ammonium polyethyleneimine nanoparticles. J Prosthet Dent. 2016;116:603–9.

    Article  PubMed  Google Scholar 

  16. Cheng LZ. One-year water-ageing of calcium phosphate composite containing nano-silver and quaternary ammonium to inhibit biofilms. Int J Oral Sci. 2016;8:172–81.

    Article  PubMed  PubMed Central  Google Scholar 

  17. Yue SW. Novel dental adhesive resin with crack self-healing, antimicrobial and remineralization properties. J Dent. 2018;75:48–57.

    Article  PubMed  Google Scholar 

  18. Wassel MOK. Antibacterial activity against Streptococcus mutans and inhibition of bacterial induced enamel demineralization of propolis, miswak, and chitosan nanoparticles based dental varnishes. J Adv Res. 2017;8:387–92.

    Article  PubMed  PubMed Central  Google Scholar 

  19. Covarrubias CT. Synthesis of hybrid copper-chitosan nanoparticles with antibacterial activity against cariogenic Streptococcus mutans. Dent Mater J. 2018;37:379–84.

    Article  PubMed  Google Scholar 

  20. Raszewski Z, Brząkalski D, Jałbrzykowski M, Pakuła D, Frydrych M, Przekop RE. Novel multifunctional spherosilicate-based Coupling agents for Improved Bond Strength and Quality in Restorative Dentistry. Materials. 2022;15(10):3451.

    Article  PubMed  PubMed Central  Google Scholar 

  21. Thomas S, Somasekharan L. Polyhedral Oligomeric Silsesquioxane (POSS) Polymer Nanocomposites: From Synthesis to Applications, Elsevier2021.

  22. I.T. 80004-1., nanotechnologies – vocabulary – part 1: core terms. International Organization for Standardization., (2010).

  23. Sood K, Kaur J, Singh H, Arya SK, Khatri M. Comparative toxicity evaluation of graphene oxide (GO) and zinc oxide (ZnO) nanoparticles on Drosophila melanogaster. Toxicol Rep. 2019;6:768–81.

    Article  PubMed  PubMed Central  Google Scholar 

  24. Melo MA, Guedes SF, Xu HH, Rodrigues LK. Nanotechnology-based restorative materials for dental caries management. Trends Biotechnol. 2013;31(8):459–67.

    Article  PubMed  Google Scholar 

  25. Kumar KS, Savadi PS, John RC. Nanodentistry: a paradigm shift-from fiction to reality. J Indian Prosthodont Soc. 2011;11(1):1–6.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Gaiser DH, Bunk S, White O, Muller SN. Understanding nano-anatomy of healthy and carious human teeth: a prerequisite for ¨ nanodentistry. Biointerphases. 2012;7(4):1–4.

    Google Scholar 

  27. Besinis DPT, Tredwin A, Handy CJ. Review of nanomaterials in dentistry: interactions with the oral microenvironment, clinical applications, hazards, and benefits. ACS Nano. 2015;9(3):2255–89.

    Article  PubMed  Google Scholar 

  28. Bapat CT, Joshi RA, Bapat CP, Choudhury PR, Pandey H, Gorain M, Kesharwani B. An overview of application of silver nanoparticles for biomaterials in dentistry. Mater Sci Eng C Mater Biol Appl. 2018;1(91):881–98.

    Article  Google Scholar 

  29. Fernandez SA, Fonseca CC, Stanisic MS, Araújo D, Azevedo DB, Portela V, Tasic RD. Applications of silver nanoparticles in Dentistry: advances and Technological Innovation. Int J Mol Sci. 2021;22(5):2485.

    Article  PubMed  PubMed Central  Google Scholar 

  30. Kasraei S, Sami L, Hendi S, AliKhani M-Y, Rezaei-Soufi L, Khamverdi Z. Antibacterial properties of composite resins incorporating silver and zinc oxide nanoparticles on Streptococcus mutans and Lactobacillus. Restor Dentistry Endodontics. 2014;39(2):109–14.

    Article  Google Scholar 

  31. Fernandes GL, Delbem ACB, Do Amaral JG, Gorup LF, Fernandes RA, de Souza Neto FN, Souza JAS, Monteiro DR, Hunt AMA, Camargo ER. Nanosynthesis of silver-calcium glycerophosphate: promising association against oral pathogens. Antibiotics. 2018;7(3):52.

    Article  PubMed  PubMed Central  Google Scholar 

  32. Cao W, Zhang Y, Wang X, Chen Y, Li Q, Xing X, Xiao Y, Peng X, Ye Z. Development of a novel resin-based dental material with dual biocidal modes and sustained release of ag + ions based on photocurable core-shell AgBr/cationic polymer nanocomposites. J Mater Science: Mater Med. 2017;28(7):103.

    Google Scholar 

  33. Xie XW. Novel dental adhesive with triple benefits of calcium phosphate recharge, protein-repellent and antibacterial functions. Dent Mater. 2017;33:553–63.

    Article  PubMed  Google Scholar 

  34. Gutierrez MFM. The role of copper nanoparticles in an etch-and-rinse adhesive on antimicrobial activity, mechanical properties and the durability of resin-dentine interfaces. J Dent. 2017;61:12–20.

    Article  PubMed  Google Scholar 

  35. Alberto Perez-Diaz MB. Silver nanoparticles with antimicrobial activities against Streptococcus mutans and their cytotoxic effect. Mater Sci Eng C Mater Biol Appl. 2015;55:360–6.

    Article  Google Scholar 

  36. Liu YN. P.C., Topical ferumoxytol nanoparticles disrupt biofilms and prevent tooth decay in vivo via intrinsic catalytic activity., Nat Commun 9 (2018).

  37. Elgamily HME-S, Contemp. Clin Dent. 2018;9:457–62.

    Google Scholar 

  38. Esteban Florez FLH. Antibacterial dental adhesive resins containing nitrogen-doped titanium dioxide nanoparticles. Mater Sci Eng C Mater Biol Appl. 2018;93:931–43.

    Article  PubMed  Google Scholar 

  39. Dutra-Correa M, Leite AA, de Cara SP, Diniz IM, Marques MM, Suffredini IB, Fernandes MS, Toma SH, Araki K, Medeiros IS. Antibacterial effects and cytotoxicity of an adhesive containing low concentration of silver nanoparticles. J Dent. 2018;77:66–71.

    Article  PubMed  Google Scholar 

  40. Garcia PPNS, Cardia MFB, Francisconi RS, Dovigo LN, Spolidório DMP, de Souza AN, Rastelli AC, Botta. Antibacterial activity of glass ionomer cement modified by zinc oxide nanoparticles. Microsc Res Tech. 2017;80(5):456–61.

    Article  PubMed  Google Scholar 

  41. Paiva L, Fidalgo T, Da Costa L, Maia L, Balan L, Anselme K, Ploux L, Thiré R. Antibacterial properties and compressive strength of new one-step preparation silver nanoparticles in glass ionomer cements (NanoAg-GIC). J Dent. 2018;69:102–9.

    Article  PubMed  Google Scholar 

  42. Rodrigues RW, Viana MC, Souza MM, Gonçalves TR, Tanaka F, Bueno-Silva CJ, Seabra B. Biogenic synthesis and antimicrobial activity of silica-coated silver nanoparticles for esthetic dental applications. J Dent. 2020;96:103327.

    Article  PubMed  Google Scholar 

  43. Tuncdemir MT, Gulbahce N. Addition of antibacterial agent effect on color stability of composites after immersion of different beverages. J Esthetic Restor Dentistry. 2019;31(5):508–13.

    Article  Google Scholar 

  44. Brandão NL, Portela MB, Maia LC, Antônio A, Silva VLM. E.M.d. Silva, Model resin composites incorporating ZnO-NP: activity against S. mutans and physicochemical properties characterization, J Appl Oral Sci 26 (2018).

  45. da Silva LH, Feitosa SA, Valera MC, de Araujo MA, Tango RN. Effect of the addition of silanated silica on the mechanical properties of microwave heat-cured acrylic resin. Gerodontology. 2012;29(2):e1019–23.

    Article  PubMed  Google Scholar 

  46. Balos S, Pilic B, Markovic D, Pavlicevic J, Luzanin O. Poly (methyl-methacrylate) nanocomposites with low silica addition. J Prosthet Dent. 2014;111(4):327–34.

    Article  PubMed  Google Scholar 

  47. Cevik P, Yildirim-Bicer AZ. The effect of silica and prepolymer nanoparticles on the mechanical properties of denture base acrylic resin. J Prosthodont. 2018;27(8):763–70.

    Article  PubMed  Google Scholar 

  48. Rashahmadi S, Hasanzadeh R, Mosalman S. Improving the mechanical properties of poly methyl methacrylate nanocomposites for dentistry applications reinforced with different nanoparticles. Polym-Plast Technol Eng. 2017;56(16):1730–40.

    Article  Google Scholar 

  49. Karci M, Demir N, Yazman S. Evaluation of flexural strength of different denture base materials reinforced with different nanoparticles. J Prosthodont. 2019;28(5):572–9.

    Article  PubMed  Google Scholar 

  50. Gad MM, Abualsaud R, Al-Thobity AM, Baba NZ, Al‐Harbi FA. Influence of addition of different nanoparticles on the surface properties of poly (methylmethacrylate) denture base material. J Prosthodont. 2020;29(5):422–8.

    Article  PubMed  Google Scholar 

  51. Zhang X-Y, Zhang X-J, Huang Z-L, Zhu B-S, Chen R-R. Hybrid effects of zirconia nanoparticles with aluminum borate whiskers on mechanical properties of denture base resin PMMA. Dent Mater J. 2014;33(1):141–6.

    Article  PubMed  Google Scholar 

  52. Gad MM, Rahoma A, Al-Thobity AM, ArRejaie AS. Influence of incorporation of ZrO2 nanoparticles on the repair strength of polymethyl methacrylate denture bases. Int J Nanomed. 2016;11:5633.

    Article  Google Scholar 

  53. Alhavaz A, Rezaei Dastjerdi M, Ghasemi A, Ghasemi A, Alizadeh Sahraei A. Effect of untreated zirconium oxide nanofiller on the flexural strength and surface hardness of autopolymerized interim fixed restoration resins. J Esthetic Restor Dentistry. 2017;29(4):264–9.

    Article  Google Scholar 

  54. Ergun G, Sahin Z, Ataol AS. The effects of adding various ratios of zirconium oxide nanoparticles to poly (methyl methacrylate) on physical and mechanical properties. J Oral Sci. 2018;60(2):304–15.

    Article  PubMed  Google Scholar 

  55. Gad MM, Abualsaud R, Rahoma A, Al-Thobity AM, Al-Abidi KS, Akhtar S. Effect of zirconium oxide nanoparticles addition on the optical and tensile properties of polymethyl methacrylate denture base material. Int J Nanomed. 2018;13:283.

    Article  Google Scholar 

  56. Elmadani A, Radović I, Tomić NZ, Petrović M, Stojanović DB, Heinemann RJ, Radojević V. Hybrid denture acrylic composites with nanozirconia and electrospun polystyrene fibers. PLoS ONE. 2019;14(12):e0226528.

    Article  PubMed  PubMed Central  Google Scholar 

  57. Sodagar A, Kassaee MZ, Akhavan A, Javadi N, Arab S, Kharazifard MJ. Effect of silver nano particles on flexural strength of acrylic resins. J Prosthodontic Res. 2012;56(2):120–4.

    Article  Google Scholar 

  58. Munikamaiah RL, Jain SK, Pal KS, Gaikwad A. Evaluation of Flexural Strength of Polymethyl Methacrylate modified with silver Colloidal Nanoparticles subjected to two different curing cycles: an in vitro study. J Contemp Dent Pract. 2018;19(3):262–8.

    Article  PubMed  Google Scholar 

  59. Bacali C, Baldea I, Moldovan M, Carpa R, Olteanu DE, Filip GA, Nastase V, Lascu L, Badea M, Constantiniuc M. Flexural strength, biocompatibility, and antimicrobial activity of a polymethyl methacrylate denture resin enhanced with graphene and silver nanoparticles. Clin Oral Invest. 2020;24:2713–25.

    Article  Google Scholar 

  60. Kumar A, Kumar R, Vamshikiran K, Deepthi G, Kumar N, Akhilesh M. Evaluation of Impact Strength of Dental Acrylic Resins by Incorporation of TiO 2 nanoparticles using two different Processing techniques. J Contemp Dent Pract. 2019;20(10):1184–9.

    Article  Google Scholar 

  61. Protopapa P, Kontonasaki E, Bikiaris D, Paraskevopoulos KM, Koidis P. Reinforcement of a PMMA resin for fixed interim prostheses with nanodiamonds. Dent Mater J. 2011;30(2):222–31.

    Article  PubMed  Google Scholar 

  62. Kamonkhantikul K, Arksornnukit M, Takahashi H. Antifungal, optical, and mechanical properties of polymethylmethacrylate material incorporated with silanized zinc oxide nanoparticles. Int J Nanomed. 2017;12:2353.

    Article  Google Scholar 

  63. Tijana A, Valentina V, Nataša T, Miloš H-M, Suzana GA, Milica B, Yoshiyuki H, Hironori S, Ivanič A, Rebeka R. Mechanical properties of new denture base material modified with gold nanoparticles. J Prosthodontic Res. 2021;65(2):155–61.

    Article  Google Scholar 

  64. El-Negoly SA, El-Fallal AA, El-Sherbiny IM. A new modification for improving shear bond strength and other mechanical properties of conventional glass-ionomer restorative materials. J Adhes Dent. 2014;16(1):41–7.

    PubMed  Google Scholar 

  65. Garcia-Contreras R, Scougall-Vilchis RJ, Contreras-Bulnes R, Sakagami H, Morales-Luckie RA, Nakajima H. Mechanical, antibacterial and bond strength properties of nano-titanium-enriched glass ionomer cement. J Appl Oral Sci. 2015;23:321–8.

    Article  PubMed  PubMed Central  Google Scholar 

  66. Ibrahim MA, Meera Priyadarshini B, Neo J, Fawzy AS. Characterization of chitosan/TiO2 nano-powder modified glass‐ionomer cement for restorative dental applications. J Esthetic Restor Dentistry. 2017;29(2):146–56.

    Article  Google Scholar 

  67. Hamid N, Telgi RL, Tirth A, Tandon V, Chandra S, Chaturvedi RK. Titanium Dioxide nanoparticles and cetylpyridinium chloride enriched glass-ionomer restorative cement: a comparative study assessing compressive strength and antibacterial activity. J Clin Pediatr Dentistry. 2019;43(1):42–5.

    Article  Google Scholar 

  68. Gjorgievska E, Van Tendeloo G, Nicholson JW, Coleman NJ, Slipper IJ, Booth S. The incorporation of nanoparticles into conventional glass-ionomer dental restorative cements. Microsc Microanal. 2015;21(2):392–406.

    Article  PubMed  Google Scholar 

  69. Gjorgievska E, Nicholson JW, Gabrić D, Guclu ZA, Miletić I, Coleman NJ. Assessment of the impact of the addition of nanoparticles on the properties of Glass–Ionomer cements. Materials. 2020;13(2):276.

    Article  PubMed  PubMed Central  Google Scholar 

  70. Jowkar Z, Jowkar M, Shafiei F. Mechanical and dentin bond strength properties of the nanosilver enriched glass ionomer cement. J Clin Experimental Dentistry. 2019;11(3):e275.

    Google Scholar 

  71. Chen J, Zhao Q, Peng J, Yang X, Yu D, Zhao W. Antibacterial and mechanical properties of reduced graphene-silver nanoparticle nanocomposite modified glass ionomer cements. J Dent. 2020;96:103332.

    Article  PubMed  Google Scholar 

  72. Barandehfard F, Rad MK, Hosseinnia A, Khoshroo K, Tahriri M, Jazayeri H, Moharamzadeh K, Tayebi L. The addition of synthesized hydroxyapatite and fluorapatite nanoparticles to a glass-ionomer cement for dental restoration and its effects on mechanical properties. Ceram Int. 2016;42(15):17866–75.

    Article  Google Scholar 

  73. Alatawi RA, Elsayed NH, Mohamed WS. Influence of hydroxyapatite nanoparticles on the properties of glass ionomer cement. J Mater Res Technol. 2019;8(1):344–9.

    Article  Google Scholar 

  74. Sajjad A, Bakar WZW, Mohamad D, Kannan TP. Characterization and enhancement of physico-mechanical properties of glass ionomer cement by incorporating a novel nano zirconia silica hydroxyapatite composite synthesized via sol-gel. AIMS Mater Sci. 2019;6(5):730–47.

    Article  Google Scholar 

  75. Sayyedan F, Fathi M, Edris H, Doostmohammadi A, Mortazavi V, Hanifi A. Effect of forsterite nanoparticles on mechanical properties of glass ionomer cements. Ceram Int. 2014;40(7):10743–8.

    Article  Google Scholar 

  76. Noori KF. The effect of magnesium oxide nanoparticles on the antibacterial and antibiofilm properties of glass-ionomer cement. Heliyon. 2019;5:e02568.

    Article  PubMed  PubMed Central  Google Scholar 

  77. Xia Y, Zhang F, Xie H, Gu N. Nanoparticle-reinforced resin-based dental composites. J Dent. 2008;36(6):450–5.

    Article  PubMed  Google Scholar 

  78. Al Jafary M, Hashem MI, Al Khadhari MA, Alshammmery SA, Assery MK. Effect of nanoparticles on Physico-Mechanical properties of Flowable Dental Composite resins. Sci Adv Mater. 2019;11(7):986–93.

    Article  Google Scholar 

  79. Hojati AH, Hamze S, Ahmadian Babaki F, Rajab-Nia F, Rezvani R, Kaviani MB, Atai M. Antibacterial, physical and mechanical properties of flowable resin composites containing zinc oxide nanoparticles. Dent Mater. 2013;29:495–505.

    Article  Google Scholar 

  80. Swetha VC, Uloopi DL, RojaRamya KS, Chandrasekhar KS. Antibacterial and mechanical properties of pit and fissure sealants containing zinc oxide and calcium fluoride nanoparticles. Contemp Clin Dent. 2019;10(3):477.

    Article  PubMed  PubMed Central  Google Scholar 

  81. Baloš PB, Petronijević S, Marković B, Mirković D, Šarčev S. Improving mechanical properties of flowable dental composite resin by adding silica nanoparticles. Vojnosanit Pregl. 2013;70(5):477–83.

    Article  PubMed  Google Scholar 

  82. Barot T, Rawtani D, Kulkarni P. Physicochemical and biological assessment of silver nanoparticles immobilized Halloysite nanotubes-based resin composite for dental applications. Heliyon. 2020;6(3):e03601.

    Article  PubMed  PubMed Central  Google Scholar 

  83. Gutiérrez MP, Matos MF, Szesz TP, Souza A, Bermudez S, Reis J, Loguercio A, Farago AD. Mechanical and microbiological properties and drug release modeling of an etch-and-rinse adhesive containing copper nanoparticles. Dent Mater. 2017;1(33):309–20.

    Article  Google Scholar 

  84. Gutiérrez A-AL, Méndez-Bauer MF, Bermudez L, Dávila-Sánchez J, Buvinic A, Hernández-Moya S, Reis N, Loguercio A, Farago AD, Martin PV. Biological, mechanical and adhesive properties of universal adhesives containing zinc and copper nanoparticles. J Dent. 2019;1(82):45–55.

    Article  Google Scholar 

  85. Torres-Rosas R, Torres-Gómez N, García-Contreras R, Scougall-Vilchis RJ, Domínguez-Díaz LR. Argueta-Figueroa, Copper nanoparticles as nanofillers in an adhesive resin system: an in vitro study. Dent Med Probl. 2020;57(3):239–46.

    Article  PubMed  Google Scholar 

  86. Sadat-Shojai M, Atai M, Nodehi A, Khanlar LN. Hydroxyapatite nanorods as novel fillers for improving the properties of dental adhesives: synthesis and application. Dent Mater. 2010;26(5):471–82.

    Article  PubMed  Google Scholar 

  87. Zhang CL, Imazato K, Antonucci S, Lin JM, Lin-Gibson NJ, Bai S, Xu Y. Effects of dual antibacterial agents MDPB and nano-silver in primer on microcosm biofilm, cytotoxicity and dentine bond properties. J Dent. 2013;41(5):464–74.

    Article  PubMed  PubMed Central  Google Scholar 

  88. Argueta-Figueroa S-VR, Morales-Luckie L, Olea-Mejía RA. An evaluation of the antibacterial properties and shear bond strength of copper nanoparticles as a nanofiller in orthodontic adhesive. Aust Orthod J. 2015;31(1):42–8.

    PubMed  Google Scholar 

  89. Felemban NH, Ebrahim MI. The influence of adding modified zirconium oxide-titanium dioxide nano-particles on mechanical properties of orthodontic adhesive: an in vitro study. BMC Oral Health. 2017;17:1–8.

    Article  Google Scholar 

  90. Viapiana R, Flumignan D, Guerreiro-Tanomaru J, Camilleri J, Tanomaru‐Filho M. Physicochemical and mechanical properties of zirconium oxide and niobium oxide modified P ortland cement‐based experimental endodontic sealers. Int Endod J. 2014;47(5):437–48.

    Article  PubMed  Google Scholar 

  91. Barros SM, Rodrigues J, Alves MA, Lopes FR, Pina-Vaz MA, Siqueira I Jr. Antibacterial, physicochemical and mechanical properties of endodontic sealers ammonium polyethylenimine nanoparticles., Int Endod J. 47(8) (2014) 725 – 34.

  92. Topouzi M, Kontonasaki E, Bikiaris D, Papadopoulou L, Paraskevopoulos KM, Koidis P. Reinforcement of a PMMA resin for interim fixed prostheses with silica nanoparticles. J Mech Behav Biomed Mater. 2017;69:213–22.

    Article  PubMed  Google Scholar 

  93. Balos S, Balos T, Sidjanin L, Markovic D, Pilic B, Pavlicevic J. Study of PMMA biopolymer properties treated by microwave energy. Mater Plast. 2011;48(2):127–31.

    Google Scholar 

  94. Alla RK, Sajjan S, Alluri VR, Ginjupalli K, Upadhya N. Influence of fiber reinforcement on the properties of denture base resins, (2013).

  95. Bellamy K, Limbert G, Waters MG, Middleton J. An elastomeric material for facial prostheses: synthesis, experimental and numerical testing aspects. Biomaterials. 2003;24(27):5061–6.

    Article  PubMed  Google Scholar 

  96. Qu R, Chen X, Hu J, Fu Y, Peng J, Li Y, Chen J, Li P, Liu L, Cao J. Ghrelin protects against contact dermatitis and psoriasiform skin inflammation by antagonizing TNF-α/NF-κB signaling pathways. Sci Rep. 2019;9(1):1–14.

    Article  Google Scholar 

  97. Murakami N, Wakabayashi N, Matsushima R, Kishida A, Igarashi Y. Effect of high-pressure polymerization on mechanical properties of PMMA denture base resin. J Mech Behav Biomed Mater. 2013;20:98–104.

    Article  PubMed  Google Scholar 

  98. Soygun K, Bolayir G, Boztug A. Mechanical and thermal properties of polyamide versus reinforced PMMA denture base materials. J Adv Prosthodont. 2013;5(2):153–60.

    Article  PubMed  PubMed Central  Google Scholar 

  99. Shuai C, Feng P, Yang B, Cao Y, Min A, Peng S. Effect of nano-zirconia on the mechanical and biological properties of calcium silicate scaffolds. Int J Appl Ceram Technol. 2015;12(6):1148–56.

    Article  Google Scholar 

  100. Maji P, Choudhary R, Majhi M. Structural, optical and dielectric properties of ZrO2 reinforced polymeric nanocomposite films of polymethylmethacrylate (PMMA). Optik. 2016;127(11):4848–53.

    Article  Google Scholar 

  101. Reyes-Acosta M, Torres-Huerta AM, Dominguez-Crespo MA, Flores-Vela AI, Dorantes-Rosales HJ. Ramírez-Meneses, influence of ZrO2 nanoparticles and thermal treatment on the properties of PMMA/ZrO2 hybrid coatings. J Alloys Compd. 2015;643:150–S158.

    Article  Google Scholar 

  102. Gad M, ArRejaie AS, Abdel-Halim MS, Rahoma A. The reinforcement effect of nano-zirconia on the transverse strength of repaired acrylic denture base, International journal of dentistry 2016 (2016).

  103. Köroğlu A, Şahin O, Kürkçüoğlu I, Dede DÖ, Özdemir T, Hazer B. Silver nanoparticle incorporation effect on mechanical and thermal properties of denture base acrylic resins. J Appl Oral Sci. 2016;24:590–6.

    Article  PubMed  PubMed Central  Google Scholar 

  104. Kassaee M, Akhavan A, Sheikh N, Sodagar A. Antibacterial effects of a new dental acrylic resin containing silver nanoparticles. J Appl Polym Sci. 2008;110(3):1699–703.

    Article  Google Scholar 

  105. She W. Basic study of denture base resin with nano-silver antibacterial agent. Dent Mater J. 2004;27:176–80.

    Google Scholar 

  106. Powers J, Sakaguchi L. Craig’s restorative dental materials, Philadelphia, 2006.

  107. Walls A. Glass polyalkenoate (glass-ionomer) cements: a review. J Dent. 1986;14(6):231–46.

    Article  PubMed  Google Scholar 

  108. Moshaverinia A, Ansari S, Moshaverinia M, Roohpour N, Darr JA, Rehman I. Effects of incorporation of hydroxyapatite and fluoroapatite nanobioceramics into conventional glass ionomer cements (GIC). Acta Biomater. 2008;4(2):432–40.

    Article  PubMed  Google Scholar 

  109. Arita K, Yamamoto A, Shinonaga Y, Harada K, Abe Y, Nakagawa K, Sugiyama S. Hydroxyapatite particle characteristics influence the enhancement of the mechanical and chemical properties of conventional restorative glassionomer cement. Dent Mater J. 2011;30(5):672–83.

    Article  PubMed  Google Scholar 

  110. Li F, Li Z, Liu G, He H. Long-term antibacterial properties and bond strength of experimental nano silver-containing orthodontic cements. J Wuhan Univ Technology-Mater Sci Ed. 2013;28(4):849–55.

    Article  Google Scholar 

  111. Lin J, Zhu J, Gu X, Wen W, Li Q, Fischer-Brandies H, Wang H, Mehl C. Effects of incorporation of nano-fluorapatite or nano-fluorohydroxyapatite on a resin-modified glass ionomer cement. Acta Biomater. 2011;7(3):1346–53.

    Article  PubMed  Google Scholar 

  112. Shiekh RA, Ab Rahman I, Luddin N. Modification of glass ionomer cement by incorporating hydroxyapatite-silica nano-powder composite: Sol–gel synthesis and characterization. Ceram Int. 2014;40(2):3165–70.

    Article  Google Scholar 

  113. Rahman IA, MASUDI SAM, Luddin N, Shiekh RA. One-pot synthesis of hydroxyapatite–silica nanopowder composite for hardness enhancement of glass ionomer cement (GIC). Bull Mater Sci. 2014;37:213–9.

    Article  Google Scholar 

  114. Gu Y, Yap A, Cheang P, Koh Y, Khor K. Development of zirconia-glass ionomer cement composites. J Non-cryst Solids. 2005;351(6–7):508–14.

    Article  Google Scholar 

  115. Rajabzadeh G, Salehi S, Nemati A, Tavakoli R, Hashjin MS. Enhancing glass ionomer cement features by using the HA/YSZ nanocomposite: a feed forward neural network modelling. J Mech Behav Biomed Mater. 2014;29:317–27.

    Article  PubMed  Google Scholar 

  116. Fathi M, Kharaziha M. Two-step sintering of dense, nanostructural forsterite. Mater Lett. 2009;63(17):1455–8.

    Article  Google Scholar 

  117. Naguib GH, Nassar HM, Hamed MT. Antimicrobial properties of dental cements modified with zein-coated magnesium oxide nanoparticles. Bioactive Mater. 2021;8:8, 49–56.

    Article  Google Scholar 

  118. Naguib HA, Al-Hazmi G, Kurakula F, Al-Dharrabh M, Alkhalidi A. Zein based magnesium oxide nanowires: Effect of anionic charge on size, release and stability. Digest J Nanomaterials Biostructures. 2017;12:741–9.

    Google Scholar 

  119. Naguib HK, Hassan GH, Al Hazmi AH, Al Dharrab F, Alkhalidi A. Zein based magnesium oxide nanoparticles: Assessment of antimicrobial activity for dental implications. Pak J Pharm Sci. 2018;31:245–50.

    PubMed  Google Scholar 

  120. Naguib NM, Mirdad G, Mirdad L, Merdad F, Alturki Y, Bakhsh B, Turkistani T A and, Hamed M. Surface characteristics of composite resin enhanced by new antibacterial nanofillers. Int J Curr Adv Res 2018:7;10(D);15965-9 7(0(D)) (2018) 15965–9.

  121. Algarni H, AlShahrani I, Ibrahim EH, Eid RA, Kilany M, Ghramh HA, Abdellahi MO, Shaaban ER, Reben M, Yousef ES. Synthesis, mechanical, in vitro and in vivo bioactivity and preliminary biocompatibility studies of bioglasses. Sci Adv Mater. 2019;11(10):1458–66.

    Article  Google Scholar 

  122. Demarco CM, Cenci FF, Moraes MS, Opdam RR. Longevity of posterior composite restorations: not only a matter of materials. Dent Mater. 2012;28:87–101.

    Article  PubMed  Google Scholar 

  123. Knobloch LA, Kerby RE, Seghi R, Berlin JS, Clelland N. Fracture toughness of packable and conventional composite materials. J Prosthet Dent. 2002;88(3):307–13.

    Article  PubMed  Google Scholar 

  124. Zohaib K, Muhammad Z, Saad Q, Sana S, Mustafa N, Ammar A. Advances in nanotechnology for restorative dentistry. Mater Eng. 2015;8:717–31.

    Google Scholar 

  125. Liu F, Wang R, Shi Y, Jiang X, Sun B, Zhu M. Novel Ag nanocrystals based dental resin composites with enhanced mechanical and antibacterial properties. Progress in Natural Science: Materials International. 2013;23(6):573–8.

    Article  Google Scholar 

  126. Sun J, Forster AM, Johnson PM, Eidelman N, Quinn G, Schumacher G, Zhang X. W.-l. Wu, improving performance of dental resins by adding titanium dioxide nanoparticles. Dent Mater. 2011;27(10):972–82.

    Article  PubMed  Google Scholar 

  127. Harini P, Mohamed K, Padmanabhan T. Effect of Titanium dioxide nanoparticles on the flexural strength of polymethylmethacrylate: an in vitro study. Indian J Dent Res. 2014;25(4):459.

    Article  PubMed  Google Scholar 

  128. Van Landuyt KL, Snauwaert J, De Munck J, Peumans M, Yoshida Y, Poitevin A, Coutinho E, Suzuki K, Lambrechts P, Van Meerbeek B. Systematic review of the chemical composition of contemporary dental adhesives. Biomaterials. 2007;28(26):3757–85.

    Article  PubMed  Google Scholar 

  129. De Munck Jd, Van Landuyt K, Peumans M, Poitevin A, Lambrechts P, Braem M, Van Meerbeek B. A critical review of the durability of adhesion to tooth tissue: methods and results. J Dent Res. 2005;84(2):118–32.

    Article  PubMed  Google Scholar 

  130. Vaidyanathan T, Vaidyanathan J. Recent advances in the theory and mechanism of adhesive resin bonding to dentin: a critical review, Journal of Biomedical Materials Research Part B: Applied Biomaterials: An Official Journal of The Society for Biomaterials, The Japanese Society for Biomaterials, and The Australian Society for Biomaterials and the Korean Society for Biomaterials 88(2) (2009) 558–578.

  131. D.H. Pashley, E.J. Swift Jr, Dentin bonding, Journal of esthetic and restorative dentistry: official publication of the American Academy of Esthetic Dentistry...[et al.] 20(3) (2008) 153–154

  132. Mitra SB, Wu D, Holmes BN. An application of nanotechnology in advanced dental materials. J Am Dent Association. 2003;134(10):1382–90.

    Article  Google Scholar 

  133. Atai M, Solhi L, Nodehi A, Mirabedini SM, Kasraei S, Akbari K, Babanzadeh S. PMMA-grafted nanoclay as novel filler for dental adhesives. Dent Mater. 2009;25(3):339–47.

    Article  PubMed  Google Scholar 

  134. Marelli B, Le Nihouannen D, Hacking SA, Tran S, Li J, Murshed M, Doillon CJ, Ghezzi CE, Zhang YL, Nazhat SN. Newly identified interfibrillar collagen crosslinking suppresses cell proliferation and remodelling. Biomaterials. 2015;54:126–35.

    Article  PubMed  Google Scholar 

  135. Toledano SS, Cabello M, Watson I, Osorio T. A Zn-doped etch-and-rinse adhesive may improve the mechanical properties and the integrity at the bonded-dentin interface. Dent Mater. 2013;29(8):e142–52.

    Article  PubMed  Google Scholar 

  136. Bakhadher W, Halawany H, Talic N, Abraham N, Jacob V. Factors affecting the shear bond strength of orthodontic brackets–a review of in vitro studies. Acta Med. 2015;58(2):43–8.

    Google Scholar 

  137. Borzabadi-Farahani A, Borzabadi E, Lynch E. Nanoparticles in orthodontics, a review of antimicrobial and anti-caries applications. Acta Odontol Scand. 2014;72(6):413–7.

    Article  PubMed  Google Scholar 

  138. Ferracane J, Condon J. Post-cure heat treatments for composites: properties and fractography. Dent Mater. 1992;8(5):290–5.

    Article  PubMed  Google Scholar 

  139. Loza-Herrero M, Rueggeberg E, Caughman W, Schuster G, Lefebvre CA, Gardner E. Effect of heating delay on conversion and strength of a post-cured resin composite. J Dent Res. 1998;77(2):426–31.

    Article  PubMed  Google Scholar 

  140. Aydin Sevinç B, Hanley L. Antibacterial activity of dental composites containing zinc oxide nanoparticles. J Biomedical Mater Res Part B: Appl Biomaterials. 2010;94(1):22–31.

    Article  Google Scholar 

  141. Sodagar AM, Bahador A, Jalali A, Behzadi Y, Elhaminejad Z, Mirhashemi F. Effect of TiO2 nanoparticles incorporation on antibacterial properties and shear bond strength of dental composite used in Orthodontics. Dent Press J Orthod. 2017;22(5):67–74.

    Article  Google Scholar 

  142. I. Council on Dental Materials, Equipment, American National Standards Institute/American Dental Association Specification No. 61 for zinc polycarboxylate cement. J Am Dent Association. 1980;101(4):669–71.

    Google Scholar 

  143. I.O.f.S. ISO6876, Root Canal Sealing Materials., Dentistry. (2012).

Download references

Acknowledgments

Special thanks to Jumana Mazhar for copyediting.

Funding

No funds, grants, or other support was received.

Author information

Authors and Affiliations

Authors

Contributions

Conceptualization: G.N, A.M. and M.T.H.; Methodology and data collection: G.N., A.M., A.I.M., H.M., M.H. and M.T.H.; Contributed data/analysis tools and formal analysis: G.N., A.M., H.M., M.H. and M.T.H.; Investigation: G.N, A.M., A.I.M., H.M., M.H. and M.T.H.; Data curation: G.N., A.M., A.I.M., H.M., M. H. and M.T.H.; Writing—original draft preparation: G.N., A.M., M.H., and M.T.H.; Writing—review and editing, G.N., A.M., A.I.M., H.M., M.H., and M.T.H.; Visualization: G.N., A.M., A.I.M., and M.T. H.; Funding acquisition: A.I.M., H.M. and M.T.H.

Corresponding author

Correspondence to Ghada Naguib.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Conflict of interest

The authors have no competing interests to declare that are relevant to the content of this article.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Naguib, G., Maghrabi, A.A., Mira, A.I. et al. Influence of inorganic nanoparticles on dental materials’ mechanical properties. A narrative review. BMC Oral Health 23, 897 (2023). https://doi.org/10.1186/s12903-023-03652-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12903-023-03652-1

Keywords