Table 1.
Research included in the study.
| Experimental Model | Endpoints | References |
|---|---|---|
| Amalgam | ||
| Human gingival fibroblast cells (HGFCs) exposed to microhybrid resin-based composite, compomer resin, glass-ionomer cement and amalgam alloy for 7 and 21 days | The levels of total oxidant status (TOS) in the study groups (i.e., samples with the following materials: microhybrid resin-based composite, compomer resin, glass-ionomer cement and amalgam alloy; shaped as a 2-mm-thick disk with a diameter of 10 mm; exposed to light with the wavelength of 430–480 nm and intensity of 1200 mW/cm2) were significantly higher in freshly prepared samples compared to the control. After 7 and 21 days, TOS level in the amalgam sample was considerably lower than at the beginning of the study. The highest level of total antioxidant capacity (TAC) was observed after 7 days in the filling with glass-ionomer cement (which prevented TOS increase). In all studied groups, TAC level after 7 days was different than at the initial stage of the study. | [19] |
| Unstimulated saliva of 48 generally healthy children aged 6–10 (24 males, 24 females) with two class II dental composite or amalgam restorations and the control (caries-free) group | The saliva of patients with composite fillings had significantly higher TAC compared to patients with amalgam fillings as well as caries-free subjects. However, TAC in patients with amalgam restorations was also significantly higher compared to the caries-free control. Patients with composite fillings also demonstrated decreased salivary levels of Ca2+ ions. | [20] |
| Saliva from 60 generally healthy subjects aged 15–40 with class I restorations of: amalgam (20 participants), composite (20 subjects) and glass-ionomer (20 patients), collected before the filling as well as 24 h and 7 and 14 days after the filling | Malondialdehyde (MDA) level in the saliva of patients with an amalgam filling was found to be higher than in patients with a composite or glass-ionomer filling. Significant differences were also observed between MDA concentrations on day 7 and 14, and after 24 h and 7 days in patients with composite fillings. There were no differences in MDA levels before treatment and 7 days after, or before and 14 days after the treatment. In the case of glass-ionomer, a significant difference was found only between 24 h and 7 days after the treatment. |
[21] |
| Urine collected from 106 generally healthy children aged 5–15.5 years with amalgam fillings | It was shown that in children with amalgam filling, there was a reduced excretion of 8-hydroxy-2-deoxyguanosine (8-OHdG) in the urine. It was also shown that the level of NAG in the urine of children with amalgam fillings was significantly higher compared to children without such fillings and was positively correlated with the level of MDA in the urine. There was no correlation between the concentration of 8-OHdG and malondialdehyde (MDA) in the urine of amalgam-filled children. The mercury (Hg) level was also significantly higher in children with amalgam fillings compared to children without amalgam fillings; however, no relationship was found between the Hg level and the number of fillings. |
[22] |
| Hair samples collected from 42 generally healthy women (mean age 44 years) with amalgam fillings applied at least 10 years earlier | An increased activity of SOD-1 and an increase in GSH concentration in the hair of women with amalgam fillings as compared to women without such fillings were observed. A positive correlation was also shown between the concentration of aluminum (Al) and the concentration of GSH, and between the level of mercury (Hg) and the activity of SOD-1. |
[23] |
| Blood collected from 41 generally healthy patients (17–23 years old), which used amalgam (19) and dental resin composite (22) fillings | A significant increase in the level of malondialdehyde (MDA) was observed 24 h after placing amalgam and composite filling. There were no changes in the concentration of 8-OHdG in women 24 h after the placement of the amalgam filling. The 8-OHdG level increased 24 h after placing the dental resin composite filling. |
[24] |
| Dental Resin Composites—monomers | ||
| Human dental pulp cells (hDPCs) exposed to dental monomers (1 mM HEMA, 5 mM MMA and 1 mM TEGDMA) without and in the presence of 10 mM NAC for 24, 48, 72 and 96 h | In response to 6 h of exposure to dental monomers: 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and methyl methacrylate (MMA), there was a significant increase in ROS production in hDPCs compared to the control group without dental monomers. The addition of N-acetyl cysteine (NAC) decreased ROS production in the monomer-treated group. The presence of monomers also GSH level, which was observed for NAC as well, but to a lesser extent. No significant differences in the content of GSSG (oxidized disulfide) were observed for HEMA and MMA monomers, and a slight GSSG decrease was noted for TEGDMA (triethylene glycol dimethacrylate). In the case of dental monomers, MDA level increased, and after adding NAC—MDA level dropped almost to its level observed in the control group. Moreover, SOD activity decreased in the presence of all dental monomers, which was not observed after the addition of NAC. After 24 h of cell exposure to monomers, CAT activity increased significantly, and decreased after the use of NAC. | [25] |
| Human dental pulp cells isolated form third molars, exposed to dental monomers (bisphenol-A-glycidyl Methacrylate, Bis-GMA; urethane dimethacrylate, UDMA; and triethylene glycol dimethacrylate, TEGDMA) at concentrations of 10, 30, 100, 300 µm for 48 h |
The level of free radicals was measured after 48 h of monomer action by means of 2′,7′-dichlorodihydrofluorescein diacetate (DCF) fluorescent dye, and it was observed that Bis-GMA and UDMA, at high concentrations (30, 100), induced a significant increase in oxidative stress, while the TEGDMA monomer did not trigger OS at any concentration. All monomers reduced the level of GSH. | [26] |
| Smulow-Glickman (S-G) human gingival epithelial cells and pulp fibroblasts (HPF) exposed to HEMA at the concentrations of 0.01–10 mm for 24 h | Higher HEMA concentrations (1, 2.5, 5, 10) caused a significant increase in the level of intracellular ROS in cells exposed to the monomer. | [27] |
| Gingival fibroblasts obtained during the extraction of premolars for orthodontic reasons, exposed to TEGDMA at a concentration of 0.6 mM and 1 mM for 15 min to 6 h | 15-min exposure to TEGDMA significantly reduced the concentration of intracellular GSH compared to cells not exposed to this monomer. It was also demonstrated that TEGDMA-induced time-dependent increase of thiobarbituric acid reactive substances (TBARS), which indicates increased lipid peroxidation. |
[28] |
| Human dental pulp stem cells (isolated from third molars) exposed to monomer HEMA (at a concentration of 2 mM) and AC (at 50 µg·mL−1) for 24 h | 2-hydroxyethyl methacrylate (HEMA) increased the level of reactive oxygen species (ROS), pro-inflammatory mediators such as nuclear factor-κB (NF-kB) and inflammatory cytokines such as interleukin. In the presence of vitamin C, these changes were less noticeable. This indicates a protective effect of vitamin C on the dental pulp cells. | [29] |
| Human gingival fibroblasts (HGFs) treated with a relatively low level of 2-hydroxyethyl methacrylate (HEMA) for 0, 24 and 96 h | After 24 and 96 h of HGF exposure to the HEMA monomer (3 mmol·L−1), it was observed that ROS levels increased 8 and 11 times compared to the control not exposed to the monomer. | [30] |
| Primary human gingival fibroblasts (HGFs) and immortalized oral keratinocyte cell line OKF6/TERT2 treated with 2-hydroxyethyl methacrylate (HEMA) at a concentration of 0.5–10 mM | Significantly induced transcription of genes related to defense against oxidative stress was demonstrated for: nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase (HO-1), quinone dehydrogenase 1 (NQO1), superoxide dismutase 1 (SOD1) in both cell types exposed to the HEMA monomer. The transcription of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and interleukin-6 (IL-6) was repressed in both cell types, while the transcription of tumor necrosis factor α (TNF-α) and interleukin-8 (IL-8) was repressed only in OKF6/TERT-2 cells. |
[31] |
| Primary human dental pulp cells (hDPCs) obtained from healthy patients aged 18–25, during the extraction of healthy third molars, exposed to 1 mM 2-hydroxyethyl methacrylate (HEMA) for 18 and 12 h | It was demonstrated that the expression of NFE2L2 (nuclear factor, erythroid 2 like 2) and HMOX1 (heme oxygenase (decycling) 1) genes encoding the proteins: Nrf2 (nuclear factor erythroid 2-related factor 2) and HO-1 (heme oxygenase 1) in the HEMA-exposed group increased compared to the group not exposed to HEMA. | [32] |
| Human gingival fibroblasts (HGFs) exposed to 2-hydroxyethyl methacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA) at a concentration of 3 mM for 24, 48 and 72 h | It was demonstrated that exposure to HEMA caused autophagy and apoptosis in each of the analyzed periods of time. No signs of autophagia were observed in TEGDMA-exposed cells | [33] |
| Dental Resin Composites—Cross-linked samples | ||
| Human dental pulp cells exposed to methacrylate-based dental resin composite, including triethylene glycol dimethacrylate and composites free of 2-hydroxyethyl methacrylate and silorane-based composite (5 mm in diameter and 2 mm high) cured with light (780 mW/cm2) for 40 s in the presence of dental polymers (reduction of free radical polymerization) and absence of polyester film | Flow cytometry showed increased ROS production in cells exposed to dental resin composite materials. A positive correlation was observed between ROS production and cell survival in groups not covered with polyester film. TEGDMA increases ROS production. |
[34] |
| Human dental pulp cells (isolated from third molars) exposed to dental material dental resin composite s for 48 h with IGF-1 i TGF-b | Insulin-like growth factor (IGF-1) and transforming growth factor beta (TGF-β) increased cystine capture, resulting in elevated levels of cellular glutathione in a group of cells exposed to dental resin composite (Flow Line, 9.5 +/− 0.4 mg and Durafill VS, 10.0 +/− 0.4 mg). This provided increased protection against OS effect triggered by dental resin composite. | [35] |
| Human pulp cells obtained from impacted third molars, exposed to cured bonding agents (Clearfil SE Bond, CB; Prime & Bond 2.1, PB; and Single Bond, SB) at a concentration of 10 µL for 2 days | Dentine bonding agents decrease the level of GSH, which might be the reason for the cytotoxicity of resins. Cytotoxicity decreased when N-acetyl-L-cysteine (NAC) was added to the sample. | [36] |
| Saliva collected from 52 patients (32 women and 20 men) who had been treated with Filtek Z250 dental resin composite fillings, before the filling and 1 h, 1 day, 7 and 30 days after the filling | Patients with dental resin composite fillings demonstrated a significantly increased MDA level compared to subjects without fillings, but there were no statistical differences between the studied time periods. There was also a significant decrease in SOD activity 7 days after the filling compared to the controls. No significant differences were noted in SOD values between day 7 and 30 in patients with dental resin composite fillings. |
[37] |
| Composite resins | ||
| Human gingival fibroblasts (HGFs) exposed to composite resin (consisting of 45% 2-hydroxyethyl methacrylate—HEMA and 55% bisphenol A-glycidyl dimethacrylate—Bis-GMA) at concentrations of up to 0.25 mM | It was demonstrated that the expression of 8-hydroxyguanine in DNA– hydrolase I, the main enzyme for repairing 8-oxoG damage in composite resin-exposed cells, was elevated compared to cells not exposed to monomers. | [38] |
| Mouse fibroblast cells (NIH/3T3) exposed to camphorquinone (CQ), CQ and diphenyleneiodonium hexafluorophosphate (DPI), CQ and ethyl 4-dimethylamino benzoate (EDAB), and CQ, EDAB and DPI, with EDAB in high and low concentration, for 10 and 20 s | Increased activity of SOD was observed after 10 s of polymerization vs 20 s in NIH/3T3. | [39] |
| Orthodontic braces | ||
| L929 mouse fibroblast cell line exposed to six types of orthodontic archiwires (stainless steel, nickel-titanium, copper-nickel-titanium, rhodium-coated nickel-titanium, cobalt-chromium Blue Elgiloy, titanium-molybdenum) in 1-cm-long pieces (1 mL saliva per 0.2 g of the wire) | It was demonstrated that a standard nickel-titanium orthodontic archiwire generates the strongest oxidative stress, while stainless steel and titanium-molybdenum wire triggers the lowest OS in a mouse fibroblast cell culture. | [40] |
| L929 mouse fibroblast cell line exposed to three conventional (stainless steel, monocrystalline sapphire ceramics, polyurethane) and four self-ligating brackets (stainless steel body with a nickel-titanium clip, aluminum oxide ceramics with a cobalt-chromium clip, aluminum oxide ceramics with a nickel-cobalt clip coated with rhodium, polycarbonate-stainless steel brackets) made of different materials | The assessment of 8-hydroxy-29-deoxyguanosine (8-OHdG) in DNA of L929 murine fibroblast cell line demonstrated that the lowest OS is triggered by a conventional sapphire ceramic bracket. Full metal conventional and self-ligating brackets and conventional polyurethane brackets showed higher OS compared to cells not exposed to these brackets. The highest OS is caused by full metal and polyurethane brackets. |
[41] |
| Saliva of 23 patients aged 12–16 enrolled in the study (12 female, 11 male subjects), treated with multibracket self-ligating vestibular orthodontic appliances | During the first 10 weeks of treatment with multibracket self-ligating vestibular orthodontic appliances, no statistically significant changes in the salivary antioxidant test (SAT) were observed. | [42] |
| Unstimulated saliva and gingival fluid of 50 generally healthy patients (27 females and 23 males) aged 13–20, treated with permanent brackets, collected before the treatment as well as in the 1st and 6th month of the treatment | There was no increase in oxidative damage (8-OHdG, MDA) in the saliva and gingival fluid of patients treated with permanent brackets compared to pre-treatment results. | [43] |
| Unstimulated (UWS) and stimulated (SWS) saliva of 37 generally healthy subjects treated with permanent orthodontic brackets, collected immediately after the fitting of the brackets as well as 1 week and 24 weeks after the fitting | There was a significant increase in thiobarbituric acid reactive substance (TBARS) in UWS and SWS one week after braces were fitted. The measured values returned to their initial state 24 weeks after the beginning of the treatment. There were no significant differences between the levels of SOD1, CAT, UA and Px activity in UWS 1 week and 24 weeks after the start of treatment. SOD1 activity was found to be significantly lower in SWS, and Px activity was considerably higher 1 week after the placement of the brackets compared to the values before the treatment and 24 weeks after its commencement. The total antioxidant status (TAS) in UWS and SWS was also found to be considerably lower 24 weeks after the start of the treatment compared to the values before the treatment as well as 1 week after its start. The highest oxidative stress index (OSI) values were observed 1 week after the treatment. 24 weeks after the treatment these values were identical to pre-treatment results. |
[44] |
| Fixations and dental implants | ||
| Human dental pulp stem cells (DPSC) and murine pre- osteoblast (MC3T3-E1) cells exposed to zirconium and titanium oxide for 24 h | Intracellular oxidation of 5-(and -6)- chloromethyl-2′,7′-dichlorodihydrofluorescein diacetate and acetyl ester (CM-H2DCFDA), a ROS indicator dye, demonstrated relatively higher average ROS levels in both types of cells exposed to zirconium compared to titanium. | [45] |
| Periosteum of 30 patients (8 women and 22 men) with bilateral fractures of the mandible, treated with Ti6Al4V titanium alloy | The periosteum of patients treated with titanium implants showed significantly higher concentrations of the biomarkers of nitrosative (S-nitrosothiols, peroxynitrite, nitrotyrosine) and oxidative stress (malondialdehyde, protein carbonyls, dityrosine, kynurenine and N-formylkynurenine) compared to the control without titanium fixations. Osteosynthesis patients also demonstrated increased antioxidant protection expressed in elevated levels of reduced glutathione (↑GSH) and glutathione reductase (↑GR). The periosteum of patients with titanium fixations revealed a considerable decrease in the activity of mitochondrial complex I (−77.8%) and CS (citrate synthase) (−166.7%) compared to the control. There were no statistically significant differences in the activity of complex II and cytochrome C oxidase (COX) between patients after osteosynthesis as compared to healthy controls. In the periosteum of osteosynthesis patients, the production of hydrogen peroxide as well as the rate of ROS production were also significantly increased. Titanium implants caused oxidative/nitrosative stress and mitochondrial dysfunction. Moreover, a positive correlation between ROS production rate and GSH concentration was observed, which may suggest increased antioxidant defense in patients after osteosynthesis. |
[46] |
| Whole saliva of patients aged 43–57 with peri-implantitis and five titanium implants (collected from five patients) that were rejected up to 6 months after their implantation (3 from the mandible, 2 from the maxilla); oxidative stress parameters | In the course of peri-implantitis, a significant increase was observed in AGE compared to the control. In the saliva of peri-implantitis patients the level of OS was higher than in healthy individuals. | [47] |
| Periosteum of 32 patients operated on due to class III dentofacial deformities (21 women and 11 men aged 20–30), who had had titanium implants inserted and then removed 12–30 months after the implantation | Decreased activity of superoxide dismutase-1 (SOD1) (↓37%) and tryptophan level (↓34%) as well as significantly higher content of advanced oxidation protein products (AOPP) (↑25%), total oxidant status (TOS) (↑80%) and oxidative stress index (OSI) (↑101%) were observed in the maxillary periosteum of osteotomized patients compared to the controls. The mandibular periosteum demonstrated a significant decrease in SOD-1 activity (↓55%), total oxidant status (TAC) (↓58.6%), advanced glycation end products (AGE) (↓60%) and N-formylkynurenine (↓34%), and considerably increased content of AOPP (↑38%), malondialdehyde (MDA) (↑29%), 4-hydroxynonenal (4-HNE) (↑114%), TOS (↑99%) and OSI (↑381%) compared to the controls. Further weakening of the redox economy and increased ROS production were demonstrated in the mandibular periosteum compared to the maxillary periosteum. |
[48] |
| Periosteum of 29 patients (aged 19–29) treated with titanium implants (due to a bilateral mandibular shaft fracture) that were removed 3–5 months after the procedure | The periosteum of patients after osteosynthesis showed significantly higher activity of NADPH and xanthine oxidase, and increased rate of free radical production compared to the control. The periosteum of patients after osteosynthesis also demonstrated a considerable increase in the levels of inflammation markers: interleukin 1 (IL-1), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), transforming growth factor β (TGF-β) and β-glucuronidase (GLU) as well as markers of apoptosis (Bax, Bax/Bcl-2), caspase-3 (CAS-3) and nitric oxide (NO) compared to the control. Titanium implants increased the production of proinflammatory cytokines and oxygen free radicals. A positive correlation between titanium content and CAS-3 activity was also demonstrated. |
[49] |
| Periosteum, plasma, and erythrocytes collected from 31 generally healthy subjects aged 21–29 (11 women and 20 men) with bilateral mandibular fractures treated with titanium miniplates (Ti4Al4V) | Decreased CAT activity in the mandibular periosteum and its increase in erythrocytes of patients with mandibular fracture treated with titanium miniplates were demonstrated compared to the subjects not exposed to titanium implants. SOD activity and UA concentration were significantly higher in both plasma and periosteum of fracture patients compared to healthy individuals. No differences were found in GPx activity between the studied groups. There was an increase in TAC, FRAP, TOS, AGE, AOPP, 4-HNE and a decrease in OSI level in the maxillary periosteum of patients with fracture compared to healthy subjects. There were no significant differences in plasma TAC, TOS, OSI, FRAP AGE, AOPP, 4-HNE and 8-OHdG levels between patients with a fracture and healthy subjects. A positive correlation was observed between TAC concentration in the mandibular periosteum and plasma UA level in patients with a mandibular fracture. A positive correlation was also found between TOS concentration in the periosteum and CAT activity in erythrocytes, and between 8-OHdG level in the periosteum and GPx activity in erythrocytes. |
[50] |
| Periodontology | ||
| Male adult Wistar rats (2 months of age) with periodontitis, subjected to antimicrobial photodynamic therapy (aPDT) | PDT was shown to increase ROS formation as well as boost the antioxidant response. | [51] |
| Whole saliva of patients aged 43–57 with peri-implantitis and 5 titanium implants (collected from five patients), which were rejected up to 6 months after their implantation (3 from the mandible, 2 from the maxilla) |
In patients with peri-implantitis, the western blot technique revealed a significant increase in AGE compared to healthy controls. By means of TBARS assays, a higher level of OS was also observed in the saliva of peri-implantitis patients compared to healthy subjects. | [47] |
| Sixteen patients with chronic periodontitis (CP), undergoing non-surgical periodontal therapy alone as well as non-surgical therapy accompanied by antibiotic therapy of Amoxicillin + Metronidazole, 500 mg each, 3 times daily, for 7 days | It was demonstrated that after 3 months OS levels decreased from very high to average during antibiotic therapy, as shown by reduced derivatives of reactive oxygen metabolites (d-ROMs) (from 491.83 ± 134.85 U CARR to 375.58 ± 126.06 U CARR) and reduced glutathione (GSH) (from 48.73 ± 33.89 μmol/L to 46.46 ± 21.59 μmol/L) in plasma. | [52] |
| Nineteen patients with chronic periodontitis (average age: 46.8 years) examined before the therapy (scaling and root planing) as well as 1 and 2 months after the therapy. | Non-surgical treatment of periodontitis reduced plasma ROM levels compared to pre-treatment levels. | [53] |
| Tissues and saliva of 10 patients with peri-implantitis and 10 with chronic periodontitis, aged 40–60 | In both the saliva and tissues of patients with peri-implantitis and chronic periodontitis, AGE levels more than doubled compared to healthy individuals. A strong positive correlation was also observed between ROS and AGE in the examined patients. |
[54] |
| Peri-implant crevicular fluid (PICF) collected from 31 patients | The concentration of MDA, SOD and TAC in peri-implant crevicular fluid did not differ from that in healthy subjects. However, there was a positive correlation between periodontal pocket depth (PPD) around the implant and MDA and TAC levels. | [55] |
| Whitening | ||
| Human primary periodontal ligament fibroblasts (hPDLFs) and Ca9-22 human gingival epithelial cells treated with stable aqueous ozone ultrafine bubble water (OUFBW; ozone concentration: 2.5 ppm) or UV-inactivated OUFBW | OUFBW (30 min of incubation) stimulated ROS production in both cell lines, thus activating the MAPK pathway. OUFBW triggered the activation of c-Fos, a major component of the transcription factor activator protein 1 (AP-1), and also nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2), which demonstrated high sensitivity to oxidative stress. | [56] |
| One-hundred thirteen patients (60 people using Crest® 3D Whitestrips® premium plus, 10% hydrogen peroxide, 53 subjects in the control group). Oral epithelial cells and saliva samples were collected at the beginning of the study and 30 days later from the control group, and immediately before whitening as well as 15 and 30 days after the completion of the whitening procedure | After the whitening procedure, an elevated level of 8-OHdG in saliva and a positive correlation between oxidative stress produced by hydrogen peroxide and micronuclei were found. | [57] |