Cytotoxicity of Methacrylate Dental Resins to Human Gingival Fibroblasts.

This study aimed to assess the acute and delayed cytotoxicity of three, popular light-cured methacrylate-based restorative resins (MRs): Charisma (C), Estelite (E), and Filtek (F), to human gingival fibroblasts in culture. Cells were grown for up to 24 h with light-cured (or pre-cured) resins. We evaluated resin cytotoxicity, redox imbalance, necrosis/apoptosis, miR-9, and heat shock protein 70 (HSP70). The role of resin-induced oxidative stress (damage) in HSP70-response (repair) was assessed using binary fluorescence labeling. All MRs decreased viable cell numbers and cell proliferation and damaged cell membranes, and their 24 h-delayed toxicity was lower (C), higher (F), or similar (E) to that induced by freshly-cured resins. Cell membrane damage induced by C and E decreased with time, while F produced a linear increase. All resins generated intracellular oxidative stress with the predominant necrotic outcome, and produced heterogeneous responses in miR-9 and HSP70. The double fluorescence (damage/repair) experiments pointed to common features of E and F but not C. In the subset of cells, the binary response induced by E and F was different from C, similar to each other, and positively interrelated. Experimental data show that selective MR cytotoxicity should be taken into account when considering repetitive use or massive reconstruction.

Impact of a toothpaste with microcrystalline hydroxyapatite on the occurrence of early childhood caries: a 1-year randomized clinical trial.

The aim of this trial was to determine whether a toothpaste with microcrystalline hydroxyapatite is not inferior to a fluoride toothpaste in prevention of caries in children. This double-blinded randomized control trial compared two toothpastes regarding the occurrence of caries lesions using International Caries Detection and Assessment System (ICDAS) ≥ code 1 on the primary dentition within 336 days. The test group used a fluoride-free hydroxyapatite toothpaste three times daily while control group used a toothpaste with fluoride. 207 children were included in the intention-to-treat analysis; 177 of them finished the study per protocol. An increase in caries ICDAS ≥ code 1 per tooth was observed in 72.7% of the hydroxyapatite-group (n = 88), compared with 74.2% of the fluoride-group (n = 89). The exact one-sided upper 95% confidence limit for the difference in proportion of participants with ICDAS increase ≥ 1 (-1.4%) was 9.8%, which is below the non-inferiority margin of 20% demonstrating non-inferiority of hydroxyapatite compared to the fluoride control toothpaste. This RCT showed for the first time, that in children, the impact of the daily use of a toothpaste with microcrystalline hydroxyapatite on enamel caries progression in the primary dentition is not inferior to a fluoride control toothpaste (Clinical Trials NCT03553966).

Cytotoxicity and Oxidative Stress Induction by Root Canal Sealers in Human Periodontal Ligament Fibroblasts: An in vitro Study.

Introduction: The aim of the study was to investigate the in vitro cytotoxicity, the profile of cell death, and the level of oxidative stress in human periodontal ligament fibroblasts (HPdLFs) after exposure to selected root canal sealers. Methods and Materials: Freshly mixed or set Endomethasone N (EN), RealSeal (RSEAL), Roeko Seal Automix (RSA), and Sealapex (SP) were incubated with HPdLFs. Fluorescein isothiocyanate (FITC)-annexin V (AnV) and propidium iodide (PI) staining followed by flow cytometry was used to identify the effects of the materials on cell viability and the profile of cell death. 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) with fluorescence-activated cell sorting was used to determine reactive oxygen species (ROS) formation in HPdLFs. Statistical analyses were performed using one-way ANOVA followed by post hoc tests, and significance was determined at P<0.05. Results: All materials reduced the viability of the cultured cells compared with the controls (P<0.05). Fresh SP and EN, and set RSA generated an increase of necrotic cells (P<0.05), whilst fresh RSEAL and RSA induced an elevation of apoptotic cells (P<0.001). Set RSEAL caused a rise in both apoptotic and necrotic cells compared with the controls (P<0.05). Fresh EN, RSEAL, and SP resulted in increased intracellular ROS generation compared with the negative control (P<0.001), whilst fresh RSA and all set materials were ineffective. Conclusions: This in vitro study showed us the materials tested were characterized by differentiated cytotoxic effects on HPdLFs. The fresh and set forms of sealers were capable of eliciting toxic action, inducing apoptosis and/or necrosis in HPdLFs. The toxic effects of fresh EN, RSEAL, and SP might have been due to the induction of oxidative stress in human periodontal fibroblasts. The cytotoxicity of RSA seemed to be related to the involvement of other mechanisms.

Performance of ICDAS II and fluorescence methods on detection of occlusal caries-An ex vivo study.

BACKGROUND: The aim of this ex vivo study was to compare the performance of the visual ICDAS II scale and two fluorescence methods (DIAGNOdent Pen and VistaCam iX) in detecting occlusal caries lesions in permanent teeth using cone beam computed tomography (CBCT) as a reference test. METHODS: One hundred-sixty molars and premolars were qualified for the study. The visual, the DIAGNOdent Pen and VistaCam iX examinations were carried out by two examiners. The actual extent of the lesions was determined using CBCT. For the three methods, inter- and intra-examiner reproducibility was calculated using intraclass correlation coefficient. The sensitivity, specificity, and accuracy of these methods were compared using the mid-P McNemar test. The level of significance was set at p < 0.05. RESULTS: For all data, intraclass-correlation coefficients (ICC) for intra- and inter-examiner reproducibility were high. With regard to the enamel threshold, the sensitivity and accuracy were significantly higher for VistaCam iX and ICDAS II compared with the DIAGNOdent Pen (p < 0.05). The results obtained with the DIAGNOdentu Pen indicated significantly higher specificity values for the enamel threshold (p < 0.05). The results obtained with the VistaCam iX showed the lowest sensitivity but the significantly highest specificity and accuracy for the dentin threshold (p < 0.05). CONCLUSIONS: The ICDAS II is an effective method for detecting early carious lesions, characterized by a higher sensitivity compared with devices using fluorescence. To improve the diagnostic efficiency of the evaluated devices, modifying the cut-off values recommended by the manufacturers should be considered.

Comparison of the radiopacity of selected materials used for vital pulp therapy: An in vitro assessment.

BACKGROUND: An assessment of the therapeutic effects of vital pulp treatment is based on both clinical and radiological evaluation. OBJECTIVES: The aim of the research was a long-term (after 1, 2, 4, 6, and 8 weeks) radiological assessment of X-ray absorption by 8 selected materials used for the vital treatment of dental pulp. MATERIAL AND METHODS: The materials, prepared in accordance with the manufacturers' recommendations, were placed in molds measuring 10 mm in diameter and 2 mm in thickness. The molds with the samples were placed on an occlusal film with an aluminum step wedge, and then X-rayed using an intraoral X-ray unit. After processing, an X-ray image with varying degrees of opacity was obtained. The radiological density of the samples, the step wedge and the background was measured 6 times using a densitometer. The tests were repeated at the following intervals: after 7 days, and after 2, 4, 6, and 8 weeks. The molds with the material samples were stored in an incubator at 37°C and 95% humidity. RESULTS: The obtained results were statistically analyzed. The mineral trioxide aggregate (MTA) materials exhibited the highest degree of contrast, whereas the lowest radiopacity was shown for the non-setting calcium hydroxide preparations (p < 0.0001). Calcium hydroxide cements presented medium radiopacity values. CONCLUSIONS: The radiopacity of all the evaluated materials showed a statistically insignificant increasing tendency with regard to the duration of the experiment. All the tested preparations showed acceptable radiopacity, enabling radiological detection in the course of vital pulp therapy.

Diagnostic validity of the use of ICDAS II and DIAGNOdent pen verified by micro-computed tomography for the detection of occlusal caries lesions-an in vitro evaluation.

The aim of this study is to assess the extent of early carious lesions using the International Caries Detection and Assessment System (ICDAS) II and DIAGNOdent pen compared with microCT examination. Forty-eight molars and premolars were qualified for the study. The visual and the DIAGNOdent pen device examinations were carried out by two examiners. The actual extent of the lesions was determined using micro-CT examination. The optimal cutoff test value was determined using the Youden index. For the two methods, inter- and intra-examiner reproducibility was calculated using intraclass correlation coefficient. The sensitivity, specificity, and accuracy of these methods were compared using the mid-P McNemar test. The level of significance was set at p < 0.05. In terms of the enamel threshold for the ICDAS II scale, insignificantly higher mean evaluated parameters were noticed in comparison with the DIAGNOdent pen device. For the dentin threshold, all the assessed parameters had higher mean values on the ICDAS II scale compared with the DIAGNOdent pen. The optimal cutoff points of the enamel and dentin thresholds are lower than that suggested by the manufacturer. The ICDAS II and the DIAGNOdent pen device were characterized by high inter - and intra-observer reproducibility of the test results. To improve the diagnostic efficiency of the DIAGNOdent pen, modifying the cutoff values recommended by the manufacturers should be considered. After modifying the cutoff values, the combination ICDAS II and DIAGNOdent pen device would be the better choice in order to detect caries on occlusal surfaces.

A comparative assessment of the antibacterial activity of root canal sealers on 2 Actinomyces species: An in vitro study.

BACKGROUND: Actinomyces species have a low virulence and pathogenicity, but under specific circumstances they may be involved in root canal and periapical tissue infections. OBJECTIVES: The aim of the study was to investigate the antibacterial activity of various root canal sealers on standardized strains of Actinomyces. MATERIAL AND METHODS: The materials tested in this study included AH Plus™ Jet (AH), Apexit® Plus (AP), Endomethasone N (EN), GuttaFlow® (GF), Hybrid Root SEAL (HB), MTA Fillapex (FL), Real® Seal (RCS), Roeko Seal Automix (RSA), Sealapex™ (SP), and Tubli-Seal™ (TS). The antibacterial effect of the freshly mixed sealers on standardized strains of Actinomyces israelii NCTC 8047 and Actinomyces viscosus ATCC 15987 was evaluated with the use of the agar diffusion test (ADT). The results were obtained by measuring the diameter of the growth inhibition zone at 96 h and 1, 2, 3, and 4 weeks, and were analyzed in time using repeated measures analysis of variance (ANOVA). Statistically significant differences among the materials were determined by using one-way ANOVA and Tukey's post hoc testing. A paired Student's t-test was applied to compare the susceptibility of particular strains to each sealer. The critical level of significance for all tests was p < 0.05. RESULTS: Most sealers demonstrated growth inhibition zones against both tested bacteria, except for RSA and GF. Actinomyces viscosus was significantly more susceptible than A. israelii to AP, RCS (p < 0.001) and TS (p = 0.012). Actinomyces israelii was significantly more susceptible than A. viscosus to EN, HB and SP (p < 0.001). CONCLUSIONS: The antimicrobial effect of the examined materials varied considerably depending on the type of material and bacterial species tested. Most of the tested root canal sealers exhibited antibacterial activity on standardized strains of Actinomyces, with FL showing the highest antibacterial effect on both bacterial strains. Importantly, both standardized strains of Actinomyces were characterized by varied sensitivity to root canal sealers.

[Importance of dental care to maintain oral health of children and youth with type 1 diabetes]. / Znaczenie opieki stomatologicznej w utrzymaniu zdrowia jamy ustnej u dzieci i mlodziezy z cukrzyca typu 1.

BACKGROUND: Dental care for children and youth with type 1 diabetes should rely on reliable examination of the oral cavity, early treatment of dental caries and maintenance of the treatment results. This can be achieved through regular control visits consistent with the standards, and also through following the recommendations for prevention of dental caries and periodontal disease. The aim of the study was to investigate whether dental care allows to preserve good oral health of children and youth with type 1 diabetes. MATERIAL AND METHODS: The study included 60 patients with type 1 diabetes, aged 7-17 years, and 30 healthy children and youth within the same age range. There were evaluated intensity of caries, the effectiveness of conservative treatment, periodontal health and oral hygiene. RESULTS: The results of examinations showed significantly lower caries prevalence and better periodontal health in the children and youth with type 1 diabetes. The effectiveness of conservative treatment was significantly higher among patients with mixed dentition. There was no significant difference in oral hygiene between the compared groups. CONCLUSIONS: Diabetes is a risk factor for oral diseases, so children and youth with type 1 diabetes should be provided with special preventive care and curative measures. The main goal of the insulin-dependent diabetes care program is to early classify them to highrisk groups to improve general oral health and thus improve the quality of life. Proper dental care for children and yuoth with type 1 diabetes is a condition to maintain oral health. Med Pr 2018;69(1):37-44.

Effect of root canal sealers on human periodontal ligament fibroblast viability: ex vivo study.

The aim of the study was to compare ex vivo the toxic effects of six root canal sealers immediately after mixing or setting on human periodontal ligament fibroblasts (HPdLF). Freshly mixed (I group) or set (allowed to dry for 24 h) (II group) specimens of AH Plus Jet (AH), Apexit Plus (AP), MTA Fillapex (FL), GuttaFlow (GF), MetaSEAL Soft (META), and Tubli-Seal (TS) were prepared. HPdLF were exposed for 24 h to the specimens. 3-(4,5-dimethylthiazolo-2-yl)-2,5-diphenyltetrazolium bromide assay was used to examine the effect of the root canal sealers on mitochondrial metabolic activity. Fluorescein isothiocyanate (FITC)-annexin V (AnV) and propidium iodide staining followed by flow cytometry was used to identify the effects of the materials on cell apoptosis/necrosis. Statistical analyses were performed by one-way ANOVA followed by post hoc tests, and significance was determined at P < 0.05. Most materials from the two groups reduced the viability of the cultured cells compared with the control group (P < 0.05). Statistical analysis showed significant differences in HPdLF viability between the individual materials in each group (P < 0.001). AH and AP induced a significant increase in the percentage of apoptotic cells, while TS, FL, and META elevated the proportion of necrotic cells compared with other materials and the controls (p < 0.05). The cytotoxic effects of the tested root canal sealers (both fresh and set) on HPdLF varied. Both forms of sealers were able to cause toxic effects by inducing apoptosis and necrosis in HPdLF. The cytotoxicity of FL, META, TS was mainly associated with necrosis, while AH and AP with apoptosis.

Evaluation of the cytotoxicity of selected conventional glass ionomer cements on human gingival fibroblasts.

BACKGROUND: Dentistry materials are the most frequently used substitutes of human tissues. Therefore, an assessment of dental filling materials should cover not only their chemical, physical, and mechanical characteristics, but also their cytotoxicity. OBJECTIVES: To compare the cytotoxic effects of 13 conventional glass ionomer cements on human gingival fibroblasts. MATERIAL AND METHODS: The assessment was conducted using the MTT test. Six samples were prepared for each material. Culture plates with cells and inserts with the materials were incubated at 37°C, 5% CO2, and 95% humidity for 24 h. Then the inserts were removed, 1 mL of MTT was added in the amount of 0.5 mg/1 mL of the medium, and the samples were incubated in the described conditions without light for 2 h. The optical density was measured with an absorption spectrophotometer at a wavelength of 560 nm. RESULTS: The cytotoxic effects of the Argion Molar was significantly stronger than the Fuji Triage (p = 0.007), Chemfil Molar (p < 0.0001), and Ionofil Molar AC Quick (p < 0.001). The Fuji IX GP and Fuji IX Extra had a significantly stronger adverse effect than the Chemfil Molar (p = 0.014, p = 0.029, respectively) and Ionofil Molar AC Quick (p = 0.017, p = 0.034, respectively). The cements from the low cytotoxicity group were significantly more toxic vs materials whose presence resulted in fibroblast growth (p < 0.001). CONCLUSIONS: The research conducted indicates that, although the materials studied may belong to the same group, they are characterized by low, yet not uniform, cytotoxicity on human gingival fibroblasts. The toxic effects should not be assigned to a relevant group of materials, but each dentistry product should be evaluated individually.

Direct Pulp Capping in Primary Molars using Mineral Trioxide Aggregate: An in Vivo Study.

OBJECTIVE: To do a clinical and radiographic evaluation of the effectiveness of MTA when used as a direct pulp capping material in primary molars. STUDY DESIGN: Clinical and radiographic follow-up was performed on 30 primary molars with deep caries lesions in 30 patients from 3 to 9.75 years of age. Pulps exposed during cavity preparation were treated by direct pulp capping with MTA. The follow-up clinical and radiographic examinations were carried out at different time intervals: 6, 7-12, 13-18, 19-24, and >24 months after treatment. RESULTS: Twenty-four teeth were evaluated during the entire observation period. Positive clinical and radiographic outcomes were achieved in 19 teeth (13 teeth were saved and 6 were exfoliated). In five teeth, complications were observed only in children under 7 years old. CONCLUSION: Based on these clinical and radiographic results, MTA was found to be successful when used as a direct pulp capping material in primary teeth.

Evaluation of cytotoxicity and pH changes generated by various dental pulp capping materials - an in vitro study.

INTRODUCTION: Various materials are used in direct dental pulp capping method. Their biocompatibility and alkalizing abilities are of primary importance affecting therapeutic effects. The aim of this study was to evaluate and compare the cytotoxicity of various pulp-capping materials on human gingival fibroblasts and investigate the pH changes induced by these materials. MATERIAL AND METHODS: Human gingival fibroblasts were cultured with nine direct pulp materials using culture plate inserts. The cytotoxic effects were recorded by using an MTT-based colorimetric assay after 3 and 24 h. In the second part of the experiment, the materials were inserted in dialysis tubes and transferred into plastic vials containing deionized water. The changes of the medium pH were measured after 3 and 24 h. RESULTS: We showed differences in cell viability of gingival fibroblasts after varied time of exposition for the tested materials. Cell viability after 24 h increased for Dycal, Biopulp, and Calcipro, and decreased for Calcipulpe, Angelus, Angelus White, and ProRoot Regular. Cell viability for ProRoot and Life did not change. Non-setting calcium hydroxide preparations followed by the MTA group and setting calcium hydroxide materials produced the highest pH. All the tested materials significantly increased pH (p < 0.0001) at 24 h. CONCLUSIONS: Currently used pulp capping materials varied in their cytotoxicity relative to human gingival fibroblasts and their alkalizing capacities. Since most likely pH does not affect the viability of cultured cells, further investigations are required to determine physicochemical properties of these materials and the biological activity of the dental pulp.

Assessment of cytotoxic potential of root canal sealers after hardening - an ex vivo study.

AIM: The aim of this study was to perform a comparative assessment of the toxic action of root canal sealers currently on the market on human gingival fibroblasts after setting. MATERIAL/METHODS: The inserts with an equal quantity of set root canal sealers were transferred into 24-well culture dishes containing human gingival fibroblasts cultured in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 10% fetal calf serum (FCS). The dishes with materials were incubated at 37°C, 100% humidity and in an atmosphere of 5% CO2 for 24 h. The cytotoxic effects of the root canal materials were measured by the mitochondrial succinate dehydrogenase activity in living cells using tetrazolium bromide (MTT assay). RESULTS: Epiphany and Sealapex exhibited high toxicity towards human gingival fibroblasts - 25.57% ± 0.88 and 27.63 % ± 2.35 respectively (less than 30% live cells in the culture). The remaining materials were characterized by lack of a cytotoxic effect (over 90% of live cells in the culture). None of the preparations exhibited moderate or low toxicity. CONCLUSIONS: The majority of root canal sealers tested after hardening were well tolerated by human gingival fibroblasts. Only two materials were characterized by high toxicity: with methacrylate (Epiphany) and calcium hydroxide (Sealapex).

Antibacterial activity of selected glass ionomer cements.

INTRODUCTION: The aim of the paper was to determine the antibacterial activity of four glass ionomer cements against bacteria of the genera Streptococcus and Lactobacillus. MATERIAL AND METHODS: Four capsulated glass ionomer cements were applied in the study: Fuji Triage (GC), Fuji IX (GC), Ketac Molar (3M Espe) and Ketac Silver (3M Espe). Four standard bacterial strains were used to assess the antibacterial activity of the studied cements: Streptococcus mutans, S. sanguis, S. salivarius and Lactobacillus casei. The antibacterial activity was determined by the agar diffusion method. The bacterial suspension was spread with a cotton swab on TSA plates. For each material six wells (7 mm diameter, 5 mm deep) were made with a cork borer. Each well was then filled with freshly prepared cements. The results were obtained by measuring the bacterial growth inhibition zone after 1, 2, 3 and 7 days. RESULTS: Fuji Triage cement inhibited the growth of all bacterial strains. Fuji IX cement demonstrated the most potent antibacterial activity against S. sanguis. Ketac Molar showed antibacterial activity against S. sanguis and S. salivarius, whereas Ketac Silver was efficient against S. mutans as well. Neither of the Ketac cements inhibited growth of the standard L. casei strain. DISCUSSION: Antibacterial activity of glass ionomer cements has attracted the interest of scientists in recent years. Most authors, including us, carried out experiments using the agar diffusion method and demonstrated antibacterial activity of glass ionomer cements. Different antibacterial activity of glass ionomer cements, observed in our study and studies of other authors, depended on the evaluated cement, bacterial strain and period of evaluation.

Antibacterial activity of two Mineral Trioxide Aggregate materials in vitro evaluation.

INTRODUCTION: It has been documented that total removal of carious dentin, assessed according to clinical criteria, does not mean complete eradication of bacteria. For that reason in prevention of caries and pulp inflammations, application of the materials having high antibacterial properties seems to be indispensable. AIM: Determination of antibacterial activities of two white Mineral Trioxide Aggregate (MTA) preparations against bacteria of the genus Streptococcus. MATERIAL AND METHODS: Antibacterial activities of the materials were determined by diffusion method on a solid tryptic-soy medium (Tryptic Soy Agar, Oxoid). Wells were prepared on the medium with a puncher of 7 mm diameter and 5 mm depth (four for each material). The bottom was poured with 10 microlitres of liquid TSA for sealing. Bacterial suspension was inoculated with cotton swabs onto the medium surface and then the wells were filled with the materials prepared ex tempore. The plates were left in room temperature for 30 minutes and incubated at 37 degrees C for 24 h. Results were read by measuring the inhibition zones on day 1, 2, 3 and 8 of the culture. RESULTS: All the study samples demonstrated inhibition of bacteria of the genus Streptococcus. The antibacterial effect of MTA was maintained till the end of the experiment (day 8). ProRoot White showed slightly larger inhibition zone against Streptococcus salivarius and Streptococcus sanguis as compared to MTA white Angelus. The mean inhibition zones against Streptococcus mutans appeared the same for both test materials. CONCLUSION: The two MTA preparations assessed in the current study show good antibacterial action against the standard strains Streptococcus mutans, Streptococcus sanguis and Streptococcus salivarius.

Fluoride release and antibacterial activity of selected dental materials.

The aim of the study was to assess the fluoride ion release and antibacterial activities of the glassionomer cement Fuji IX and the compomer (composite modified polyacid) Dyract AP. Fluoride ion release was measured using direct potentiometry with an Orion fluoride ion selective electrode. The measurement was carried out after 1, 4, 7, 14, 30, and 60 days of storage in phosphate buffer at pH 6.8. The antibacterial activity of the materials was evaluated against the bacteria Streptococcus mutans ATCC 35668, Streptococcus salivarius ATCC 13419, Streptococcus sanguis ATCC 10556, and Lactobacillus casei subsp. casei ATCC 393. The agar diffusion test was applied. The material specimens were assessed twice: after setting and seven days later. Zones of bacterial growth inhibition were measured in millimeters after 24 hours. The results of the study showed that both materials released ion fluoride, with a higher emission of Fuji IX than Dyract AP. The highest level of emission was observed on the seventh day of the study in both materials. After 24 hours of bonding there was inhibition of bacterial growth by Fuji IX, whereas Dyract AP did not show similar activity. On the eighth day after polymerization, Dyract AP was significantly more active towards Streptococcus sanguis and salivarius.