GIC Group Research Articles

In Vitro Evaluation Of Surface Roughness Of Three Class V Restorative Materials Following Prophylactic Instrumentation

Objective: This study was designed to determine which among the three Class V restorative materials - Omnichroma, GC Gold label Hybrid and Beautifil exhibits the least increase in surface roughness when subjected to manual or ultrasonic prophylactic instrumentation. Materials and methods: Class V cavity preparation were performed on 60 mandibular premolar teeth and randomly divided into 3 groups of 20 specimens each. They were restored with the assigned restorative material, i.e. Composite (Group 1), GIC (Group 2) and Giomer (Group 3). Restorations were finished and polished and then subjected to surface profilometry analysis for determining the surface roughness values followed by simulated aging by thermocycling. These groups were further subdivided into two subgroups consisting of 10 samples each and subjected to manual and ultrasonic prophylactic instrumentation followed by surface profilometric analysis. After polishing using prophylactic paste, once again surface profilometry analysis was done. The data thus obtained were subjected to statistical analysis using SPSS 26.0 (SPSS Inc., Chicago, IL) software. Results and discussion: The highest value for surface roughness was seen with Group 1 (Omnichroma) followed by Group 2 (GC Gold Label hybrid). Group 3 (Beautifil) exhibited lowest value for surface roughness along all the stages. Manual instrumentation groups showed increased surface roughness compared to ultrasonic instrumentation groups. Conclusion: Among the three tested materials, best surface finish at all stages of evaluation was seen with Beautifil, followed by GC Gold label hybrid and the lowest quality was seen with Omnichroma.

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

ObjectiveThis 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.MethodsFour 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.ResultsBoth 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).ConclusionThe 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 relevanceBiodentine has a higher remineralization ability than that of GIC for carious dentin, and its interfacial properties make it a promising bioactive dentin restorative material.

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

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. 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 24h) 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. 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. Based on the results of this study, various coatings enhance surface roughness in the initial 24h of restoration insertion. Different coat types seems that have no influence on fluoride release and the micromorphological features of the restoration/dentin interface.

Comparative Evaluation of Different Intra-orifice Barriers on the Microleakage of Endodontically Treated Roots Obturated with Gutta-percha “An In-vitro Study”

Aim: To comparatively evaluate various Intra-Orifice barriers (IOB) namely; Cention N (Ivoclar Vivadent), Biodentine (Septodont), Light Cured GIC (GC Gold Label 2LC) and Tetric N Flow (Ivoclar Vivadent) for their effects on the microleakage of endodontically treated teeth.&#x0D; Study Design: In-vitro study.&#x0D; Place of Study: Department of Endodontics and conservative dentistry, Himachal dental college, Sundarnagar, Himachal Pradesh.&#x0D; Materials and Methods: Seventy-five mandibular premolars were decoronated to a standardized length, prepared and obturated with Gutta-Percha and AH Plus sealer. Except for control specimens, the coronal 3-mm gutta-percha was removed and filled with different Intra-orifice barrier materials. The specimens (75) were divided into five groups (n = 15) on the basis of the Intra-Orifice barrier material used. Group 1: Control, Group 2: Cention N, Group 3: Biodentine, Group 4: Light Cured GIC, Group 5: Tetric N Flow. In experimental groups, 3 mm of coronal gutta-percha was removed and replaced with the study material. Samples were submerged in 2% methylene blue dye in vacuum for one week. Specimens were longitudinally sectioned and leakage measured using a 50X stereomicroscope and graded for depth of leakage.&#x0D; Results: In the present study microleakage of roots were significantly affected by the type of Intra-Orifice barrier used and the following pattern was observed: Tetric N Flow &gt; Biodentine &gt;Light Cured GIC &gt; Cention N&gt;Control.&#x0D; Conclusion: The present study concluded that Intra-Orifice barrier placement provides better coronal seal, prevents microleakage, and enhance the longevity of postobturation restorations, Tetric N Flow proved to be the best followed by Biodentine, Light Cured GIC and Control group.

Evaluation of Sealing Ability of Calcium Silicate Materials with Diode Laser for Root Furcation Repair

Background Inadequate furcation repair often leads to tooth loss due to accompanying endodontic and periodontal problems. An appropriate material and technique can prevent this. This study aimed to evaluate the sealing ability of Mineral Trioxide Aggregate MTA Glass Ionomer Cement GIC and Biodentine as a furcation repair material with and without laser.Methods Ninety human extracted mandibular molars were decoronated 3 mm above and below the cementoenamel junction. After access opening sticky wax was placed over the canal orifices. A defect of 1 mm diameter was made the chamber and perforation were flushed with water and dried. Further the specimens were divided into six groups based on the furcation repair materials used n 15. Group 1 MTA with laser Group 2 MTA Group 3 GIC with laser Group 4 GIC Group 5 Biodentine with laser and Group 6 Biodentine. In groups 1 3 and 5 diode 810 laser irradiation was done for furcal defect before placing the materials. Specimens were subjected to 2 methylene blue for 48 hr washed sectioned mesiodistally and depth of dye penetration was examined under stereomicroscope. Statistical software SPSS version 22 was used for analysis. One way analysis of variance followed by Post hoc Tukey multiple comparison test was done p le0.05.Results Among the experimental materials less microleakage was observed with laser activation than without using laser. Biodentine with laser Group 5 showed less microleakage which was statistically significant compared to all the other groups except group 6 i.e Biodentine without laser.Conclusion Biodentine with laser activation was effective in furcation repair and in prevention of microleakage.nbsp

Comparative evaluation of bioactivity, fluoride release, shear bond strength, and compressive strength of conventional glass ionomer cement incorporated with three inorganic bioactive nanoparticles: An experimental analysis.

Over the course of four decades, the bioactive materials have changed. They have become more specialized, more manageable, possessing superior qualities. Thus, it should be encouraged to conduct ongoing research to improve these materials even further in order to meet the growing clinical and restorative needs. To evaluate and compare bioactivity, fluoride release, shear bond strength and compressive strength of conventional GIC incorporated with three inorganic bioactive nanoparticles. For the study, total of 160 samples were included. The samples were divided in four groups (40 samples per group) i.e. 3 wt% of forsterite (Mg2SiO4) (Group 2), wollastonite (CaSiO3) (Group 3) and niobium pentoxide (Nb2O5) (Group 4) nanoparticles incorporated into GIC (Group 1). The bioactivity (FEG-SEM and EDX analysis), fluoride release (ion-selective electrode), shear bond strength testing (UTM followed by evaluation under stereomicroscope) and the compressive strength (UTM) was checked for each group. Wollastonite nanoparticles (3wt %) incorporated to GIC showed maximum increase in the apatite crystal formation,Ca and P content and highest fluoride release. Mean shear bond strength was highest in niobium pentoxide nanoparticles (3wt %) incorporated to GIC while mean compressive strength was highest in forsterite nanoparticles (3wt %) added to GIC. Positive results were observed which showed increase in the bioactivity alongwith enhancement of the fluoride release, shear bond strength and compressive strength but further research on these materials is warranted before its use in clinical practice.

In vivo evaluation of clinical performance of Cention N and glass ionomer cement in proximal restorations of primary molars.

Restoring a proximal lesion in primary tooth has met with many challenges which has led to evolution of many materials. An alternative to Glass Ionomer Cements which has fluoride releasing capacity, offers good bond strength and is esthetic have been long looked for. This study aimed to compare the clinical performance of GIC and Cention N in proximal restorations of primary molars. A prospective study was conducted on 154 primary molars in patients aged between 5 and 8 years using a split-mouth design. Patients were divided into two groups. Control group restored with GIC and study group received Cention N. Both groups were assessed at baseline 3, 6 and 9 months according to Ryge criteria and data was statistically analysed using Fisher's Exact. Statistically significant difference was found between GIC and Cention N restorations for color match at baseline and color stability at 3 months (P < 0.001), while the other parameters did not show any significant difference among the two restorative materials. Cention N can be used as a suitable alternative to GIC for restoring Class II restorations in primary molars.

THE EFFECTIVENESS OF COMPOMER AND GIC AGAINST PREVENTION IN ENAMEL DEMINERALIZATION

Background: Several studies showed that fluoride interferes in the dynamics involved in the development of caries and could present an antimicrobial effect or provide demineralization inhibition or dental remineralization. The development of fluoride-releasing materials can contribute to a preventive of demineralization. GIC and Compomer are restorative materials containing fluoride which can prevent demineralization. Purpose: To analyze the effectiveness of Compomer and GIC against prevention in enamel demineralization. Method: The cavities were made on 18 bovine teeth which grouped into 3 groups, each group consisting of 6 bovine teeth. After the restorative procedures, the teeth were submitted to demineralization and remineralization cycling during 14 days. The sections of the teeth were examined under scanning electron microscope after undergoing pH cycling. The data were analyzed using the Kruskal-Wallis and Tukey Test (p&lt;0.05). Results: GIC group showed the lowest lesion depth of demineralization (10.9883 ± 0.74333) followed by Compomer group (25.4183 ± 3.44268) and Control group (88.9783 ± 3.02495). Conclusion: GIC restorative materials have a better enamel demineralization prevention effect than Compomer. Keywords: compomer, demineralization, fluoride, GIC, remineralization

Influence of Cavity Size on the Survival of Single Surface Atraumatic Restorative Treatment Using Glass Ionomer Cement with or without Chlorhexidine Diacetate—A Randomized Trial

The purpose of the present study was to assess the influence of cavity size on the survival of conventional and CHX modified GIC in single surface primary molars receiving Atraumatic Restorative Treatment (ART). A randomized controlled trial with a split-mouth design was conducted on 90 children with symmetrical bilateral single surface carious lesions on primary molars. The teeth were randomly allotted to the conventional GIC group (group 1, n = 90) and CHX modified GIC group (group 2, n = 90). Both groups received atraumatic restorative treatment under rubber dam isolation. The cavity size was measured in terms of depth, mesiodistal, and buccolingual dimensions. The survival of ART restorations was measured after 6, 12, 18, and 24 months. The difference in proportion was tested using the Kruskal–Wallis H test, and survival curve estimation was carried out using the Kaplan–Meier method. The overall survival of all ART restorations was 83.3% at 24 months for the total sample. The survival of conventional GIC at 24 months was 83.9%, and for CHX-modified GIC was 82.7% (p &gt; 0.05). The collective overall success of 65.1% was seen in the cavity volume category of 10–29.9 mm3. CHX modified GIC showed high survival percentage (60%) with depth &gt;3 mm. To conclude, no significant difference was observed in the overall survival percentage of conventional and CHX modified GIC. Survival percentage was highest for cavities with a volume of 10–19.9 mm3.

Mineral exchange within restorative materials following incomplete carious lesion removal using 3D non-destructive XMT subtraction methodology

ObjectivesThe objective of this study was to quantify the changes in mineral and selected element concentrations within residual carious dentine and restorative materials following incomplete carious lesion removal (ICLR) using different cavity liners, with non-destructive subtraction 3D-X-ray Microtomography (XMT, QMUL, London, UK). Materials and methodsA total of 126 extracted teeth with deep dental caries were assessed using International Caries Risk and Assessment (ICDAS). Eight teeth were subsequently selected after radiographic evaluation. Each lesion was removed, leaving a thin layer of leathery dentine at the deepest part of cavity. Different cavity lining materials were placed; Mineral Trioxide Aggregate (MTA), calcium hydroxide, (Ca(OH)2), resin-based material (RBM). For each, the restorative material was an encapsulated glass ionomer (GIC) and the control group had a GIC restoration alone. Each tooth was immediately placed in Simulated Body Fluid (SBF). All samples were then imaged using XMT at baseline, and three weeks after treament. The XMT images were then subtracted to show the mineral concentration changes three weeks after treatment. ResultsThere were significant increases in mineral concentrations within the residual demineralised dentine in individual teeth treated with Ca(OH)2, MTA, RBM, and GIC following immersion in SBF for three weeks. GIC group without any liners showed the greatest increase in mineral concentration, followed by MTA and Ca(OH)2. ConclusionMineral changes in demineralised dentine and within restorative materials are quantifiable using non-destructive 3D-XMT subtraction methodology. This laboratory study suggested that calcium, phosphate and strontium ion-exchange occurs with GIC, MTA and Ca(OH)2 in deep dentinal lesions following ICLR. Clinical relevanceIn clinical practice, incomplete carious lesion removal could be performed to avoid the dental pulp exposure. 3D non-destructive XMT subtraction methodology in a laboratory setting is advantageous to provide evidence for different restorative materials on deep carious lesions prior to clinical investigations.

Effect of CPP ACP and Nano Hydroxyapatite Incorporated GIC on Remineralization of Dentin

The objective of this invitro study was to investigate, whether the remineralization potential of conventional GIC in human dentin could be improved by combining with CPP-ACP and nano hydroxyapatite. Class I cavities were prepared in sound human extracted third molars and they were randomly assigned to 3 groups according to the restorative materials. Group I: Conventional GIC, Group II: Conventional GIC and CPP-ACPand Group III: Conventional GIC powder & Nano hydroxy apatite. The samples were subjected to remineralizationand demineralization cycles for period of 2 weeks. Energy dispersive X-ray analysis was used to evaluate the remineralization. The elemental compositions were analyzed using One way ANOVA, Post Hoc and Mann Whitney tests. The calcium and phosphate concentration were statistically significantly greater in Group III than Group I and II (P<0.05). Nanohydroxy apatite with GIC remineralized the demineralized dentin almost equal to normal dentin.

Effect of the restorative technique on load-bearing capacity, cusp deflection, and stress distribution of endodontically-treated premolars with MOD restoration.

ObjectivesTo evaluate the influence of the restorative technique on the mechanical response of endodontically-treated upper premolars with mesio-occluso-distal (MOD) cavity.Materials and MethodsForty-eight premolars received MOD preparation (4 groups, n = 12) with different restorative techniques: glass ionomer cement + composite resin (the GIC group), a metallic post + composite resin (the MP group), a fiberglass post + composite resin (the FGP group), or no endodontic treatment + restoration with composite resin (the CR group). Cusp strain and load-bearing capacity were evaluated. One-way analysis of variance and the Tukey test were used with α = 5%. Finite element analysis (FEA) was used to calculate displacement and tensile stress for the teeth and restorations.ResultsMP showed the highest cusp (p = 0.027) deflection (24.28 ± 5.09 µm/µm), followed by FGP (20.61 ± 5.05 µm/µm), CR (17.72 ± 6.32 µm/µm), and GIC (17.62 ± 7.00 µm/µm). For load-bearing, CR (38.89 ± 3.24 N) showed the highest, followed by GIC (37.51 ± 6.69 N), FGP (29.80 ± 10.03 N), and MP (18.41 ± 4.15 N) (p = 0.001) value. FEA showed similar behavior in the restorations in all groups, while MP showed the highest stress concentration in the tooth and post.ConclusionsThere is no mechanical advantage in using intraradicular posts for endodontically-treated premolars requiring MOD restoration. Filling the pulp chamber with GIC and restoring the tooth with only CR showed the most promising results for cusp deflection, failure load, and stress distribution.

Glass Ionomer Cements can be used for Bonding Orthodontic Brackets After Cancer Radiation Treatment?

Patients undergoing radiotherapy treatment present more susceptibility to dental caries and the use of an orthodontic device increases this risk factor due to biofilm accumulation around the brackets. The objective of this study was to evaluate the shear bond strength to irradiated permanent teeth of orthodontic brackets bonded with conventional glass ionomer cement and resin-modified glass ionomer cement due to the fluoride release capacity of these materials. Ninety prepared human premolars were divided into 6 groups (n=15), according to the bonding material and use or not of radiation: CR: Transbond XT composite resin; RMGIC: Fuji Ortho LC conventional glass ionomer cement; GIC: Ketac Cem Easymix resin-modified glass ionomer cement. The groups were irradiated (I) or non-irradiated (NI) prior to bracket bonding. The specimens were subjected to a fractioned radiation dose of 2 Gy over 5 consecutive days for 6 weeks. After the radiotherapy, the brackets were bonded on the specimens with Transbond XT, Fuji Ortho LC and Ketac Cem Easymix. After 24 h, the specimens were subjected to shear bond strength test. The image of enamel surface (classified by Adhesive Remnant Index - ARI) was also evaluated and its frequency was checked among groups/subgroups. The shear bond strength variable was evaluated with ANOVA and Tukey's post-hoc test. GIC group showed the lowest adhesion values among the groups (p<0.05). There was no statistically significant difference among non-irradiated and irradiated groups (p>0.05). As for the ARI, the CR-I group showed the highest material retention on enamel surface among the irradiated groups. RMGIC group showed the highest values for shear bond strength and presented ARI acceptable for clinical practices.

Long-term treatment outcomes in immature permanent teeth by revascularisation using MTA and GIC as canal-sealing materials: a retrospective study.

Pulp revascularisation with MTA sealing has been accepted as an alternative treatment for non-vital immature permanent teeth. Successful revascularisation cases with GIC sealing were also reported, but lack of long-term researches. To evaluate long-term outcomes of revascularisation using MTA and GIC as canal-sealing materials in non-vital immature permanent teeth. Clinical and radiographic data of 60 non-vital immature permanent teeth treated with revascularisation (36.8 ± 12.4 months of follow-up) were reviewed. Of these, 28 teeth were sealed with MTA, and 32 with GIC. Tooth survival, success rate, and increases in root length and dentine wall thickness were evaluated. Teeth in MTA group showed a similar survival rate (96%) to GIC group (100%). The success rate in MTA group (93%) was greater than that in GIC group (59%). Eight of fourteen failed teeth due to recurrent apical disease (seven teeth in GIC group and one in MTA group) achieved complete root development. There was no statistically significant difference in root length or dentine wall thickness increase between the groups. Long-term outcome of revascularisation in non-vital immature permanent teeth sealed with GIC was not as good as that with MTA. Although more recurrent apical disease developed, results on root development were acceptable in GIC sealed cases.

Fluoride releasing sealants may possess minimal cariostatic effect on adjacent surfaces.

Randomised controlled trial. Children with at least two sound permanent first molars and the presence of at least one sound distal surface of adjacent second primary molar were eligible. Children were randomised into three groups. In group one first permanent molars were sealed with a high-viscosity glass ionomer cement (GIC group; n = 926), group two received a resin-based fluoride containing sealant (RBF group; n = 923) and group three a resin-based sealant without fluoride (RB group; n = 927). Two examiners blind to group allocation conducted examinations at 30 months. Sealant retention and caries at D1-D3 levels was assessed. Bitewing radiographs were taken. Caries prevalence and incidence rate ratios were calculated. Two thousand seven hundred and seventy-six children were enrolled; the number of dropouts were similar in each group (GIC group; n = 75), (RBF group; n = 67), (RB group; n = 77). The prevalence of affected surfaces was significantly lower in the GIC (p = .03) and FRB groups (p = .04). Fewer new caries developed on the distal surfaces of the second primary molars in the GIC group than in the other two groups. Incidence rate ratios (IRRs) were: 0.70 (95% CI: 0.50, 0.68; p < .01) for GIC vs. RB; 0.89 (95% CI: 0.89, 1.28; p = .10) for GIC vs. FRB and 0.79 (95% CI: 0.53, 1.04; p = .005) for FRB vs RB. Partial sealant loss was higher in the GIC group (76 molars; 2.95%), compared with FRB (52 molars; 1.41%), RB group (50 molars;1.35%). Fluoride-releasing sealants (high-viscosity GIC and fluoride RB) were demonstrated to provide protection against caries on the distal surface of second primary molars. This preventive strategy might contribute to maintaining the integrity of the mesial surfaces of the first permanent molars.

An Invitro Comparative Evaluation of Compressive Strength and Antibacterial Activity of Conventional GIC and Hydroxyapatite Reinforced GIC in Different Storage Media.

GIC is the most commonly used restorative material in pediatric dentistry since it has got various advantages like fluoride release, anticariogenic property and chemical adhesion to tooth but a major disadvantage is its contraindication in posterior teeth because of poor mechanical properties. The purpose of this study is a modest attempt to explore the influence of the addition of 8% hydroxyapatite to conventional GIC on its compressive strength when immersed in different storage media and antibacterial activity. One hundred and twenty six pellets of the specific dimension of 6 x 4 mm were prepared and divided into 6 groups and were immersed in deionized water, artificial saliva, lactic acid solution respectively for three hours everyday over 30 days test period. The compressive strength was measured by using a universal testing machine (AG-50kNG) at cross head of 1mm(2)/min and strength was determined after 1 day, 7 days, 30 days respectively and the antibacterial activity evaluated against Streptococcus mutans strain in brain heart infusion broth using serial dilution method. Group wise comparisons were made by one-way ANOVA followed by post-hoc Tukey's test, Intergroup comparison was done with Mann-Whitney test. GIC±HAp showed significantly greater antibacterial activity against Streptococcus mutans when compared to GIC group. There was no statistically significant change in the compressive strength among the groups except for group 3 and group 6 when immersed in lactic acid had shown significant difference at the end of 24 hours. The addition of 8% hydroxyapatite to GIC showed marked increased in the antibacterial activity of the conventional GIC against caries initiating organism without much increase in the compressive strength of the GIC when immersed in the different storage media.

Effect of Fluoridated Sealants on Adjacent Tooth Surfaces

A double-blind randomized clinical trial was performed in 6- to 7-yr-old schoolchildren to evaluate, in a 30-mo period, whether the caries increment on the distal surface of the second primary molars adjacent to permanent first molars sealed with fluoride release compounds would be lower with respect to those adjacent to permanent first molars sealed with a nonfluoridated sealant. In sum, 2,776 subjects were enrolled and randomly divided into 3 groups receiving sealants on sound first molars: high-viscosity glass ionomer cement (GIC group); resin-based sealant with fluoride (fluoride-RB group); and a resin-based sealant without fluoride (RB group). Caries (D1 – D3 level) was recorded on the distal surface of the second primary molar, considered the unit of analysis including only sound surfaces at the baseline. At baseline, no differences in caries prevalence were recorded in the 3 groups regarding the considered surfaces. At follow-up, the prevalence of an affected unit of analysis was statistically lower (p = .03) in the GIC and fluoride-RB groups (p = .04). In the GIC group, fewer new caries were observed in the unit of analysis respect to the other 2 groups. Incidence rate ratios (IRRs) were 0.70 (95% confidence interval: 0.50, 0.68; p < .01) for GIC vs. RB and 0.79 (95% confidence interval: 0.53, 1.04; p = .005) for fluoride-RB vs. RB. Caries incidence was significantly associated with low socioeconomic status (IRR = 1.18; 95% confidence interval: 1.10, 1.42; p = .05). Dental sealant high-viscosity GIC and fluoride-RB demonstrated protection against dental caries, and there was evidence that these materials afforded additional protection for the tooth nearest to the sealed tooth (clinical trial registration NCT01588210).

Influence of citric acid on the surface texture of glass ionomer restorative materials.

Aim:This study determined the effectiveness of G-coat plus surface protective agent over petroleum jelly on the surface texture of conventional Glass ionomer restorative materials.Materials and Methods:Three chemically cured conventional glass ionomer restorative materials type II, type IX and ketac molar were evaluated in this study. Sixty specimens were made for each restorative material. They were divided into two groups of thirty specimens each. Of the sixty specimens, thirty were coated with G-coat plus (a nano-filler coating) and the rest with petroleum jelly. Thirty samples of both protective coating agents were randomly divided into six groups of five specimens and conditioned in citric acid solutions of differing pH (pH 2, 3, 4, 5, 6 & 7). Each specimen was kept in citric acid for three hours a day, and the rest of time stored in salivary substitute. This procedure was repeated for 8 days. After conditioning, the surface roughness (Ra, μm) of each specimen was measured using a surface profilometer (Taylor & Habson, UK). Data was analyzed using one-way analysis of variance (ANOVA) and Tukey's HSD test at a significance level of 0.05.Results:The surface textures of all the tested glass ionomer restorative materials protected with G-coat plus were not significantly affected by acids at low pH. The surface textures of all the tested glass ionomer restorative materials protected with petroleum jelly coating were significantly affected by acids at low pH.Conclusion:The effects of pH on the surface texture of glass ionomer restoratives are material dependent. Among all the materials tested the surface texture of Type II GIC (Group I) revealed marked deterioration when conditioned in solutions of low pH and was statistically significant. Hence, a protective coating either with G-coat plus or with light polymerized low viscosity unfilled resin adhesives is mandatory for all the glass ionomer restorations to increase the wear resistance of the restorative materials.

Fluoride Concentration from Dental Sealants

A randomized clinical trial was performed in schoolchildren (6-7 yrs) to evaluate fluoride concentration in interproximal fluid after the placement of 3 different sealants. The sample consisted of 2,776 children randomly divided: 926 in the high-viscosity Glass-ionomer Cement group (GIC group), 923 in the fluoride Resin-based group (fluoride-RB group), and 927 in the no-fluoride Resin-based group (RB group). In total, 2,640 children completed the trial. Sealants were applied following manufacturer’s instructions. Interproximal fluid samples were collected at baseline and 2, 7, and 21 days after application of sealants, by insertion of a standardized paperpoint into the interproximal mesial space of the sealed tooth for 15 seconds. Fluoride concentration was evaluated by means of a fluoride ion-selective electrode. At 2 days after sealant application, fluoride concentration was significantly higher in GIC and fluoride-RB groups compared with that in the RB group (p < .01). Mean fluoride concentrations after 7 days were 2.54 (SE 0.68) ppm, 0.85 (SE 0.26) ppm, and 0.53 (SE 0.11) ppm for the three groups, respectively. After 21 days, fluoride concentration in the GIC group remained higher than that in the other two groups. High-viscosity GIC sealants increased the fluoride concentrations in interproximal fluid more than did a Resin-based sealant containing fluoride (ClinicalTrials.gov NCT01588210).

In-vitro Comparison of the Antimicrobial Properties of Glass Ionomer Cements with Zinc Phosphate Cements.

White spot lesions are observed in nearly 50% of patients undergoing orthodontic treatment. Long-lasting antibacterial properties of orthodontic cements can reduce this phenomenon. The aim of this research was to compare antimicrobial activity of three commercial glass ionomer cements with three commercial zinc phosphate cements, over time, against streptococcus mutans and candida albicans. Direct contact test (DCT) was used to evaluate the antibacterial and antifungal activity of products after 48 h and 7 days of incubation. The results demonstrated that all the cements presented antibacterial activity but the antibacterial activity of glass ionomer cements was more than that of zinc phosphate cements. Counts of C. albicans after 48 h were lower and statistically different in the GIC group in relation to the control groups. But no differences were observed between GIC and control groups at 7 days. Based on the results of this study, the antimicrobial and mainly antifungal effects of all the cements were so short.