Comparative Evaluation of Microleakage of Fiber-reinforced Glass Ionomer Cement and Conventional Glass Ionomer Cement Restorations Immersed in Three Different Beverages: In Vitro Study.

AIM: The aim of the study was to compare and evaluate the microleakage of fiber-reinforced glass ionomer cement (GIC) and conventional glass ionomer cement restorations immersed in three different beverages. MATERIALS AND METHODS: A total of 96 human exfoliating deciduous molars were selected which were cleaned and disinfected. Standardized Class V cavity preparations were done and buccal surface were restored with experimental fiber-reinforced glass ionomer cement (Exp-FRGIC), lingual surface were restored with Type II conventional GIC. They were divided into four groups according to the test beverage. The samples were subjected to various immersion regimes and evaluated for microleakage under stereomicroscope. RESULTS: Intragroup comparison for (Exp-FRGIC) showed significant microleakage when immersed in fresh fruit juice at high immersion whereas intragroup comparison in conventional GIC, showed highest microleakage with soft drink. Intergroup comparison of (Exp-FRGIC) in high immersion regime, showed more microleakage with specimen immersed in soft drink followed by fresh fruit juice. CONCLUSION: It can thus be concluded that the three beverages used in the study affected the microleakage of both restorative materials significantly. CLINICAL SIGNIFICANCE: Increasing usage of fruit juices in the pediatric diet has a definite impact on the progression of caries and it directly or indirectly affects the quality of restorations placed in the oral cavity. How to cite this article: George MA, Chandak SA, Khekade SH, et al. Comparative Evaluation of Microleakage of Fiber-reinforced Glass Ionomer Cement and Conventional Glass Ionomer Cement Restorations Immersed in Three Different Beverages: In Vitro Study. J Contemp Dent Pract 2024;25(4):346-353.

Comparison of remineralization ability of tricalcium silicate and of glass ionomer cement on residual dentin: an in vitro study.

OBJECTIVE: This study aimed to compare the remineralization effects of a calcium silicate-based cement (Biodentine) and of a glass ionomer cement (GIC: Fuji IX) on artificially demineralized dentin. METHODS: Four standard cavities were prepared in dentin discs prepared from 34 extracted sound human third molars. In each disc, one cavity was covered with an acid-resistant varnish before demineralization (Group 1). The specimens were soaked in a chemical demineralization solution for 96 h to induce artificial carious lesions. Thereafter, one cavity each was filled with Biodentine (Group 2) and GIC (Group 3), respectively, and one carious lesion was left unrestored as a negative control (Group 4). Next, specimens were immersed in simulated body fluid (SBF) for 21 days. After cross-sectioning the specimens, the Ca/P ratio was calculated in each specimen by using scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX). Finally, data were analyzed using repeated-measures ANOVA with post-hoc Bonferroni correction. RESULTS: Both cement types induced dentin remineralization as compared to Group 4. The Ca/P ratio was significantly higher in Group 2 than in Group 3 (p < 0.05). CONCLUSION: The dentin lesion remineralization capability of Biodentine is higher than that of GIC, suggesting the usefulness of the former as a bioactive dentin replacement material. CLINICAL RELEVANCE: Biodentine has a higher remineralization ability than that of GIC for carious dentin, and its interfacial properties make it a promising bioactive dentin restorative material.

Clinical Effectiveness of Ion-Releasing Restorations versus Composite Restorations in Dental Restorations: Systematic Review and Meta-Analysis.

BACKGROUND: To compare the clinical effectiveness of ion-releasing restorations (IRR) vs. composite resin (CR) in dental restorations. METHODS: A systematic search was carried out from articles published until January 2024, in the biomedical databases: PubMed, Cochrane Library, Scielo, Scopus, Web of Science and Google Scholar. Randomized clinical trials were included, with a follow-up time greater than or equal to 1 year, without time and language limits and which reported the clinical effect of IRR compared to CR in dental restorations. The RoB 2.0 tool was used to assess the risk of bias of the included studies and the GRADEPro GDT tool was used to assess the quality of evidence and the strength of recommendation of the results. RESULTS: The search yielded a total of 1109 articles. After excluding those that did not meet the selection criteria, 29 articles remained for the quantitative synthesis. The analysis found no statistically significant difference when comparing the dental restorations with IRRs or CRs. CONCLUSION: The literature reviewed suggests that there are no differences between the IRRs and CRs in dental restorations.

The Use of Potassium Iodide in Pediatric Dentistry Does Not Change the Retention of Glass Ionomer Cement on a Dentin Treated with Silver Fluoride: In Vitro Results.

In pediatric and operative dentistry, caries treatment benefits from a therapeutic option based on the use of silver fluoride (AgF) associated with potassium iodide (KI) to avoid dark colorations on dental tissues. The objective of this in vitro study is to evaluate the retention of glass ionomer cement (GIC) on a dentin when treated with AgF and KI. Twenty-two healthy human permanent molars and eight human primary teeth, all free of any decay, were cut to obtain occlusal flat dentinal surfaces and were then treated with AgF for a duration of 60 s. For half of the teeth, a drop of KI was applied for a duration of 30 s. All samples were covered with a plot of GIC and their resistance to shear bond strength was measured. The fracture resistance in both permanent and primary teeth does not show any statistically significant differences whether KI was applied or not. For permanent teeth, the resistance is slightly higher in the group treated with KI than in the group treated with AgF alone. To our knowledge, these data are the first to describe the possible application of KI both on primary and permanent teeth. In any case, further studies are needed to investigate the bond strength between dentin and GIC on a wider range of samples.

Effect of Zeolite Incorporation on the Ion Release Properties of Silver-Reinforced Glass Ionomer Cement.

BACKGROUND: Zeolite can release antimicrobial silver ions in a targeted and controlled manner for an extended time, selectively inhibiting the growth of pathogenic oral bacteria when added to dental materials. The objective of this study was to investigate the effect of the addition of zeolite to silver-reinforced glass ionomer cement on the release of silver ions over time. METHODS: Five concentrations of silver-zeolite (0%, 0.5%, 1%, 2%, 4% wt) were incorporated into silver-reinforced GIC in the form of 10 mm × 2 mm circular disks (n = 5). The disks were incubated in deionized water at 37 °C and ion release from the samples was measured at 1, 2, 7, and 30 days after immersion by inductively coupled atomic emission spectroscopy. RESULTS: Incorporating silver-zeolite increased silver ion release from silver-reinforced GIC disks compared to the control disks (p < 0.05), while incorporating zeolite alone had no effect. Higher concentrations of added silver-zeolite resulted in increased silver ion release. Sustained silver ion release was observed for up to 30 days. CONCLUSION: Adding silver-zeolite to silver-reinforced GIC may enhance its extended antibacterial effect in the oral cavity.

2-year survival and cost analysis of occlusoproximal ART restorations using encapsulated glass ionomer cement in primary molars: a randomized controlled trial.

BACKGROUND: The survival of ART restorations can be influenced by the choice of the restorative material. The aim of this randomized non-inferiority controlled trial was to compare the 2-year survival rate and cost analysis of two encapsulated glass ionomer cements (GIC) as occlusoproximal restorative materials in primary molars. METHODS: Children from public schools in Tietê (Brazil), aged 4-8 years with occlusoproximal dentine carious lesions in primary molars were selected and randomly assigned to receive either Equia Forte (EF) or Riva Self Cure (RSC) as restorative materials. Treatment was carried out by two trained final-year dental students in schools following ART premises. Restorations were assessed by a trained and calibrated examiner after 2, 6, 12, 18, and 24 months. The primary outcome was restoration survival after 2 years, analyzed using Kaplan-Meier survival and Cox regression analysis (α = 5%). Professional and materials costs for each group were collected in Brazilian Reais (R$) and converted into US dollars (US$) and analyzed using Monte-Carlo simulation. RESULTS: A total of 152 children (76 per group) were included in the study, and 121 (79%) were evaluated after 2 years. The overall 2-year restoration survival rate was 39% (EF = 45%; RSC = 32%) with no difference between the groups. The baseline and 2-year total cost of restorations using RSC was lower when compared to EF (incremental cost: US$ 6.18). CONCLUSION: After two years of follow-up, Riva Self Cure shows comparable restoration survival rates to Equia Forte, being more cost-effective in the Brazilian perspective. TRIAL REGISTRATION: This randomized clinical trial was registered on ClinicalTrials.Gov - NCT02730000.

Evaluation of Vertical Discrepancies in Crown Seating Using Different Glass Ionomer Cement Volume: An In Vitro Study.

Background This in vitro study aimed to assess the vertical disparities in the positioning of complete crown castings when different quantities of cement were used and to determine the optimal amount of cement for cementation while minimizing any marginal discrepancies. Methodology A total of 60 ideal nickel-chromium (Ni-Cr) crown castings were divided into three groups of experimental volumes of glass ionomer cement, with 20 castings in each group. Group I had completely filled volume with cement, group II had it half-filled, and group III had brushed up cement internally. The crowns were cemented by applying a static load of 5 kg to the cementation apparatus for 10 minutes. The marginal discrepancy between the die and the castings was measured pre-cementation and post-cementation using image analysis software in combination with a stereomicroscope (Motic, USA) at predetermined points that were marked on the die. Statistical analysis was performed using Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 16, Armonk, USA) software. A one-way analysis of variance (ANOVA) was used for the intergroup analysis. A paired sample t-test was used for intragroup analysis. Result  Brushing cement onto the internal surface presented the least mean values (P<0.05) of post-pre-cementation vertical discrepancy (14.92±10.77 µm) when compared to the half-filled cement group (28.42±12.45 µm) and the fully-filled cement group (58.50±20.91 µm). Conclusion Cement volume appeared to be a key factor in the vertical marginal discrepancy of the crown. The cement brush applied to the internal surfaces of the crown showed smaller post-cementation vertical discrepancies.

Tensile strength of conventional glass ionomer cement and silver reinforced glass ionomer cement.

A comparative analysis and assessment of the compressive strength (CS) and diametral tensile strength (DTS) between conventional glass ionomer cement (C-GIC) and a silver-reinforced GIC (S-GIC) variant is of interest. Ten specimens of both C-GIC (GC Fuji II, Japan) and S-GIC (Riva Silver, SDI, Australia) were fabricated for the evaluation of compressive strength, and an identical number of samples were created for the examination of tensile strength. These specimens were then tested using a universal testing apparatus. The results exhibited that both the compressive and diametral tensile strengths were significantly greater for the S-GIC cement in comparison to the C-GIC, with a notable p-value of 0.001. The findings suggest that S-GIC may be considered a viable alternative to conventional GIC.

Silver modified atraumatic restorative treatment: a paradigm shift in dental caries management.

Silver diamine fluoride (SDF) and atraumatic restorative treatment (ART) are treatment modalities that are minimally invasive and used for the prevention and control of dental caries. The amalgamation of these two techniques has led to the development of silver modified atraumatic restorative treatment (SMART). In this approach the carious lesion is restored with glass-ionomer cement (GIC) after SDF application. SMART effectively arrests caries without removing additional tooth structure, making it a promising option for caries management in children who lack cooperative ability.This article reviews the literature on SMART, the evidence regarding its applications in dental practice, its advantages, drawbacks, the scope for research, and clinical use.

Enhancement of mineral density and mechanical properties in root caries treated with silver diammine fluoride and glass ionomer cement, with emphasis on silver ion distribution.

OBJECTIVES: This study aimed to measure the distribution of silver ion (Ag+), mineral recovery, and nanohardness in carious lesions and comprehensively evaluate the degree of dentin restoration. METHODS: Sixty human teeth with root caries were randomly assigned to the control, silver diammine fluoride (SDF) [Safo], and SDF+Glass ionomer cement (GIC) treatment [Safo+Fuji] groups. Micro-computed tomography (micro-CT) was performed at five time points for each sample before/after treatment to evaluate mineral density within and around carious lesions. Three months following treatment, 12 samples were selected for synchrotron radiation X-ray fluorescence analysis to evaluate Ag+ distribution, while 15 samples were selected for nanoindentation. Data were analyzed using Dunnett's T3 test for micro-CT and Wilcoxon rank sum test with Bonferroni correction (p = 0.017) for nanoindentation. The correlation between hardness and mineral change was analyzed using the Spearman rank correlation coefficient. RESULTS: The Safo and Safo+Fuji groups showed significantly higher mineral recovery rates than did the control group (p < 0.001). In the Safo group, Ag+ accumulated in the deeper layers rather than the superficial layer of caries. In the Safo+Fuji group, Ag+ was found evenly distributed throughout caries, with only a few Ag+ detected in the GIC layer. Hardness in the Safo+Fuji group was significantly higher compared with the Safo group at depths in the range of 10-50 µm. CONCLUSION: In the presence of GICs, SDF exhibited high remineralization capacity when diffusing throughout carious lesions over time. Combined treatment with SDF and GIC could strengthen root dentin even in the presence of caries. CLINICAL SIGNIFICANCE: We found that combination treatment with SDF and GIC could increase mineral density in caries and improve the hardness of the tooth structure compared with fluoride-based agents alone. These findings might pave the way for future clinical trials to determine the therapeutic potential of nanotechnology-based restorative materials.

Developing a novel glass ionomer cement with enhanced mechanical and chemical properties.

OBJECTIVE: To develop a novel glass ionomer cement (NGIC) with enhanced mechanical and chemical properties and assess its biocompatibility, mechanical strength, and ion release. METHODS: Nanosilver doped bioactive glass (NanoAg BAG) was synthesized by sol-gel method and characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy and transmission electron microscopy. The NanoAg BAG, together with poly(vinylphosphonic acid) (PVPA), alumino-fluorosilicate glass and poly-acrylic acid were used to synthesize NGIC. The optimal PVPA concentration for NGIC was determined by PVPA modified GIC's biocompatibility and mechanical properties and used to prepare NGIC specimens. NGIC specimens with NanoAg BAG at 0%, 1%, 2%, and 5% were allocated into Groups NGIC0, NGIC1, NGIC2, and NGIC5, respectively. The biocompatibility, surface morphology, elemental composition, surface topography, chemical properties, compressive strength, diametral tensile strength, and ion release of the NGIC were assessed. A conventional glass ionomer cement (GIC) was used as a control. RESULTS: A granular BAG with nano silver particles attached on its surface were found, indicating the successful synthesis of NanoAg BAG. PVPA at 10% presented the best effect in enhancing the biocompatibility and mechanical properties of PVPA modified GIC and was used to prepare NGIC specimens. NGIC1 showed similar biocompatibility, surface morphology and topography to GIC. Chemical properties results showed that NGICs showed the same adsorption peaks to GIC. The compressive strength (mean±SD in MPa) was 168.1 ± 29.7, 205.5 ± 29.5, 221.8 ± 46.8, 216.6 ± 59.3 and 167.7 ± 36.4, and the diametral tensile strength (mean±SD in MPa) was 14.1 ± 1.7, 18.3 ± 4.9, 21.2 ± 2.2, 17.2 ± 3.8 and 13.3 ± 3.3 for GIC, NGIC0, NGIC1, NGIC2 and NGIC5 respectively. NIGC0, NGIC1 and NGIC2 showed higher compressive and diametral tensile strength than GIC (p < 0.01). NGIC2 and NGIC5 showed higher release of fluoride, calcium, phosphate and silver ion than GIC and NGIC0 (p < 0.05). CONCLUSION: A biocompatible NGIC with enhanced mechanical properties were developed. It presented enhanced fluoride, calcium, phosphate and silver ion release compared to conventional GIC.

Bio-inspired synthesis of silver nanoparticles usingSalsola imbricataand its application as antibacterial additive in glass ionomer cement.

Nanotechnology has gained immense popularity and observed rapid development due to the remarkable physio-chemical properties of nanoparticles (NPs) and related nanomaterials. The green production of NPs has many benefits over traditional techniques because the current procedures are expensive, time-consuming, and involve harmful substances that limit their applicability. This study aimed to use a novel green source, theSalsola imbricata(SI) plant, which is commonly found in Central Asia and known for its medicinal properties as a reducing and stabilizing agent for the synthesis of AgNPs. The current study also utilized efficient statistical design, the Plackett-Burman Design (PBD) of Experiment method to synthesize the NPs. The characterization of NPs was carried out using UV-Vis spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy (SEM). The PBD results showed that only two out of four factorsi.e.AgNO3concentration and incubation time, were significant for the synthesis of SI-AgNPs. While remaining factors, incubation temperature and plant extract: AgNO3ratio were non-significant. The SEM analysis result showed that SI-AgNPs had a size of 20-50 nm. The SI-AgNPs demonstrated strong antibacterial activity against oral pathogens such asS. mutans and Lactobacillus acidophilus, with the highest efficacy observed at a concentration of 2 mg ml-1. The addition of SI-AgNPs in glass ionomer cement significantly increased the antibacterial activity of GIC againstS. mutans. Based on the results of the current study, the plant based AgNPs can be further evaluated in detail as alternate antimicrobial agent either alone or in combination with other antimicrobial agents for different dental applications.

Effect of Luting Materials on the Accuracy of Fit of Zirconia Copings: A Non-Destructive Digital Analysis Method.

The marginal accuracy of fit between prosthetic restorations and abutment teeth represents an essential aspect with regard to long-term clinical success. Since the final gap is also influenced by the luting techniques and materials applied, this study analyzed the accuracy of the fit of single-tooth zirconia copings before and after cementation using different luting materials. Forty plaster dies with a corresponding zirconia coping were manufactured based on a single tooth chamfer preparation. The copings were luted on the plaster dies (n = 10 per luting material) with a zinc phosphate (A), glass-ionomer (B), self-adhesive resin (C), or resin-modified glass-ionomer cement (D). The accuracy of fit for each coping was assessed using a non-destructive digital method. Intragroup statistical analysis was conducted using Wilcoxon signed rank tests and intergroup analysis by Kruskal-Wallis and Mann-Whitney U tests (α = 0.05). Accuracy of fit was significantly different before/after cementation within A (0.033/0.110 µm) and B (0.035/0.118 µm; p = 0.002). A had a significantly increased marginal gap compared to C and D, and B compared to C and D (p ≤ 0.001). Significantly increased vertical discrepancies between A and B versus C and D (p < 0.001) were assessed. Of the materials under investigation, the zinc phosphate cement led to increased vertical marginal discrepancies, whereas the self-adhesive resin cement did not influence the restoration fit.

Addition of nisin to high-viscosity glass-ionomer cement: a comparative in vitro study on antibacterial and physical properties.

PURPOSE: Nisin is a lantibiotic effective against Gram-positive microorganisms such as Streptococcus mutans. The study aimed to determine the effect of the addition of nisin to high-viscosity glass-ionomer cement (HVGIC) on its antibacterial activity, setting time, surface microhardness, and compressive strength. METHODS: 1 and 3% w/w nisin were added to HVGIC before mixing. Unmodified HVGIC was the control. Agar disc diffusion, direct contact test, and scanning electron microscopy (SEM) analysis were used to evaluate antibacterial activity against S. mutans. Setting time, surface microhardness, and compressive strength were measured using Gilmore needle apparatus, digital microhardness tester, and universal testing machine, respectively. Statistical analysis included Student's t test, one-way ANOVA with Tamhane's post hoc test, and repeated-measures ANOVA. RESULTS: As evidenced by the agar disc diffusion (p < 0.001), direct contact tests (p = 0.025), and SEM analysis of the S. mutans cell count and cell surface area (p = 0.049 and 0.003), 3% nisin had the strongest antibacterial activity. There was a dose-dependent increase in setting time (p = 0.005) and surface microhardness (p = 0.006), with no significant difference in compressive strength compared to control. CONCLUSION: The addition of 3% nisin to HVGIC enhances the antibacterial action against S. mutans and surface microhardness without adversely affecting setting time and compressive strength.

Efficacy of Glass Ionomer Cement as Pit and Fissure Sealant in Permanent First Molars.

Background/Objectives Pit and fissure caries constitute a predominant portion, approximately 90% in permanent posterior teeth and 44% in primary teeth among children and adolescents. Among various preventive modalities, pit and fissure sealants play a pivotal role in safeguarding these vulnerable areas. Categorized by materials such as glass ionomer, composites, and polyacid-modified glass ionomers, these sealants offer effective protection. This study aims to evaluate the efficacy of glass ionomer-based pit and fissure sealants in terms of retention rate at 12-month post-procedure period in permanent first molars. Methodology This study was conducted at the Department of Operative Dentistry, Nishtar Institute of Dentistry, Multan, Pakistan. Fifty-six children, aged 7 to 12 years, presenting with pit and fissure caries in permanent first molar teeth were enrolled. Glass ionomer sealant was meticulously applied to the affected pits and fissures. The efficacy was assessed after 12 months based on predefined criteria. Results The age of participants ranged from 7 to 12 years, with a mean age of 9.24 ± 1.38 years. Among the 56 patients, 23 (41.2%) were male and 33 (58.8%) were female. Sealant retention was noted in 31 (55.35%) patients, while 25 (44.65%) experienced sealant loss. In the 7 to 9-year age group, 19 demonstrated complete sealant retention, whereas in the 10 to 12-year age group, 12 exhibited complete retention. Concerning gender distribution, 17 males and 14 females exhibited complete sealant retention. Conclusion Glass ionomer-based sealants demonstrate excellent properties for pit and fissure sealing owing to their low technique sensitivity, cost-effectiveness, and favorable retention rates. Therefore, they represent an optimal choice for this preventive dental procedure.

Comparing modified USPHS and FDI criteria for the assessment of glass ionomer restorations in primary molars utilising clinical and photographic evaluation.

PURPOSE: To compare the applicability of modified US Public Health Service (USPHS) and FDI criteria for evaluating glass ionomer cement (GIC) restorations in primary posterior teeth through digital image analysis. METHODS: This comparative analytic study was conducted at the Children's Dental Clinic RSKGM FKG UI, involving 40 GIC restorations on lower first primary molars in children aged 4-9 years. After cleaning, the restorations were assessed clinically using modified USPHS and FDI criteria before taking digital images, then the collected images were re-evaluated using both sets of criteria, and the clinical assessment results were compared to the digital image assessment results. RESULTS: Statistical analysis revealed significant differences between the clinical evaluation of GIC restorations in primary teeth and their corresponding digital photographs when using the modified USPHS criteria, and although the use of FDI criteria yielded different results, these differences were not statistically significant. CONCLUSION: The assessment of GIC restorations through digital images aligns more closely with clinical assessments using the FDI criteria compared to the modified USPHS criteria.

Cell viability assessment and ion release profiles of GICs modified with TiO2- and Mg-doped hydroxyapatite nanoparticles.

OBJECTIVES: To assess and compare the cell viability and ion release profiles of two conventional glass ionomer cements (GICs), Fuji IX and Ketac Molar EasyMix, modified with TiO2 and Mg-doped-HAp nanoparticles (NPs). METHODS: TiO2 NPs, synthesized via a sol-gel method, and Mg-doped hydroxyapatite, synthesized via a hydrothermal process, were incorporated into GICs at a concentration of 5 wt.%. The biocompatibility of prepared materials was assessed by evaluating their effects on the viability of dental pulp stem cells (DPSCs), together with monitoring ion release profiles. Statistical analysis was performed using One-way analysis of variance, with significance level p < 0.05. RESULTS: The addition of NPs did not significantly affect the biocompatibility of GICs, as evidenced by comparable decreased levels in cell viability to their original formulations. Distinct variations in cell viability were observed among Fuji IX and Ketac Molar, including their respective modifications. FUJI IX and its modification with TiO2 exhibited moderate decrease in cell viability, while other groups exhibited severe negative effects. While slight differences in ion release profiles were observed among the groups, significant variations compared to original cements were not achieved. Fluoride release exhibited an initial "burst release" within the initial 24 h in all samples, stabilizing over subsequent days. CONCLUSIONS: The addition of NPs did not compromise biocompatibility, nor anticariogenic potential of tested GICs. However, observed differences among FUJI IX and Ketac Molar, including their respective modifications, as well as induced low viability of DPSC by all tested groups, suggest the need for careful consideration of cement composition in their biological assessments. CLINICAL SIGNIFICANCE: The findings contribute to understanding the complex interaction between NPs and GIC matrices. However, the results should be interpreted recognizing the inherent limitations associated with in vitro studies. Further research avenues could explore long-term effects, in vivo performance, and potential clinical applications.

Effect of various surface coating methods on surface roughness, micromorphological analysis and fluoride release from contemporary glass ionomer restorations.

OBJECTIVE: To evaluate the effect of various surface coating methods on surface roughness, micromorphological analysis and fluoride release from contemporary resin-modified and conventional glass ionomer restorations. MATERIALS & METHODS: A total of 72 permanent human molars were used in this study. The teeth were randomly assigned into 2 groups according to type of restorative materials used; resin modified glass ionomer cement and conventional glass ionomer (SDI Limited. Bayswater Victoria, Australia). Each group was subdivided into 3 subgroups according to the application of coat material; Sub-group1: without application of coat; Sub-group2: manufacturer recommended coat was applied and sub-group3: customized (vaseline) coat was applied. Each group was then subdivided into two divisions according to the time of testing; immediate (after 24 h) and delayed (after 6 months of storage). Three specimens from each sub-group were selected for surface roughness test (AFM) and another 3 specimens for the micromorphological analysis using scanning electron microscope (SEM). For the fluoride release test, a total of 60 cylindrical discs were used (n = 60). The discs were randomly split into 2 groups according to type of restorative materials used (n = 30); resin modified glass ionomer cement and conventional glass ionomer. Each group was subdivided into 3 subgroups (n = 10) according to the application of the coat material; Sub-group1: without application of coat; Sub-group2: with the manufacturer recommended coat and sub-group3: with application of customized (vaseline) coat. Data for each test was then collected, tabulated, were collected, tabulated, and tested for the normality with Shapiro-Wilk test. Based on the outcome of normality test, the significant effects of variables were assessed using appropriate statistical analysis testing methods. RESULTS: Regarding the data obtained from surface roughness test, Shapiro-Wilk test showed normal distribution pattern of all values (p > 0.05). Accordingly, Two-way ANOVA outcome showed that the 'type of restoration' or 'test time' had statistically significant effect on the AFM test (p < 0.05). Regarding Fluoride specific ion electrode test 2-way ANOVA followed by Least Significant Difference (LSD) Post-hoc test revealed significant difference among the groups (p < 0.05). It showed that SDI GIC group after 14 days of measurement had the highest mean of fluoride release (36.38 ± 3.16 PPM) and SDI RMGIC after 30 days of measurement had the second highest mean of fluoride release (43.28 ± 1.89 PPM). Finally, regarding the micromorphological analysis using SEM, a slight difference was observed between the studied groups. CONCLUSIONS: Based on the results of this study, various coatings enhance surface roughness in the initial 24 h of restoration insertion. Different coat types seems that have no influence on fluoride release and the micromorphological features of the restoration/dentin interface.

Comparison of Three Different Orthodontic Adhesives Bonded to Metallic and Ceramic Brackets: SEM and SEM/EDX Analysis (In Vitro Study).

Objectives: To compare three different orthodontic adhesives (Transbond XT Light Cure Adhesive, Heliosit Orthodontic, Fuji Ortho LC) bonded to two types of orthodontic brackets: ceramic brackets (Fascination Roth 0.22) and metallic brackets (Topic Roth 0.22, Dentaurum). Materials and methods: The study was performed on 18 human teeth (6 for each adhesive). The prepared teeth were divided into three groups according to the examination time. Subsequently, they were observed after 1, 2 and 3 weeks following bonding. After the experimental procedure, the teeth samples were cut in half along the longitudinal axis in the vestibulo-oral direction, fixed with conductive carbon cement, placed in a high-vacuum evaporator and then coated with carbon. One half of each sample was observed under a Field-emission gun scanning electron microscope (FEG-SEM Hitachi SU 8030, Japan), while on the second half of the samples qualitative (X-ray line-scans) and semi-quantitative point X-ray energy dispersive analyses (EDX) were performed with Thermo Noran (USA) NSS System 7, equipped with Ultra Dry detector (30 mm2 window). Results: Transbond XT had an ideal bond with the enamel and the bracket base, with rare presence of microgaps and cracks in the enamel. Heliosit Orthodontic demonstrated a better bond relationship with the bracket base than the enamel, whereas in the latter the presence of microgaps in the bond was observed. The microphotographs of Fuji Ortho LC demonstrated many cracks inside the adhesive, and some of them continued to move forward into the enamel surface. Therefore, an impression of a very solid bond relationship with the enamel exists, with cracks being present in the enamel surface and never at the enamel-adhesive interface. Microgaps also appeared at the bracket-adhesive interface. Conclusion: Transbond XT is a highly filled composite resin and is an ideal orthodontic adhesive in each aspect examined, with an ideal enamel-adhesive and bracket-adhesive interface. Heliosit Orthodontic provides better bracket-adhesive interface compared to the enamel. Fuji Ortho LC as a solid resin-modified GIC provides a better enamel-adhesive interface, compared to the bracket base.

In Vitro Analysis of Outcome Differences Between Repairing and Replacing Broken Dental Restorations.

Objective In light of several advancements and considerations in endodontic dentistry, there still remains a need to comprehensively evaluate the outcome disparities between repairing and replacing broken dental restorations. This study aims to compare the effectiveness of repairing dental restorations versus replacing them, focusing on how each method affects the structural strength and longevity of the restorations. Methods The study included 60 freshly removed human maxillary premolars. Initial processing involved rigorous washing, descaling, and polishing of the teeth. To ensure preservation, the specimens were stored in sterile, distilled water. To occlude the root canals, a self-hardening composite resin was used, and the roots were coated with two coats of clear nail polish to prevent moisture penetration. A 245 carbide bur attached to a high-speed dental handpiece with air and water spray cooling produced standardized Class II cavities on the occluso-proximal surfaces. Each cavity had a buccolingual breadth of 2 mm, an occluso-cervical length of 4 mm, and a gingival boundary that was 1 mm coronal to the cement-enamel junction. Following this preparation, the teeth were randomly separated into three groups (Group A, Group B, and Group C), each containing 20 teeth. Results Our analysis showed that teeth with entirely replaced restorations had a higher average fracture resistance than those with repaired restorations. However, the difference in fracture resistance between the repair and replacement groups for each type of material was not statistically significant. Conclusion Based on the findings, repairing a dental restoration can be a conservative and less invasive alternative to a full replacement without a significant compromise in the restoration's ability to withstand fracture. Therefore, dental professionals might consider full restoration as a viable option, taking into account the need to preserve dental tissue as well as the restoration's durability and structural integrity.