Resin-modified Glass Ionomer Restorations Research Articles

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.

Histologic comparison of formocresol, platelet-rich fibrin, and hesperidin in pulpotomy: A randomized trial in dogs.

To histologically assess and compare formocresol (FC), platelet-rich fibrin (PRF), and hesperidin (HPN) as pulpotomy agents in dogs. Pulpotomy was attempted from the buccal surface (class V) of 48 teeth in three mongrel dogs (Canis Lupus). Cavities were randomly allocated for three groups (n = 16) according to the pulpotomy agent used; (group I: FC (control), group II: PRF, and group III: HPN). All cavities were then sealed with zinc oxide eugenol followed by resin-modified glass ionomer restoration. Two months later, dogs were euthanized; the specimens were obtained and prepared for histological assessment followed by statistical analysis. HPN specimens showed the best dentin bridge formation and the least inflammatory signs and pulp disorganization. Followed without statistically significant difference by PRF (P ≥ 0.05). Both of HPN and PRF, however, showed a significant difference statistically (P ≤ 0.05) to FC that showed no dentin bridging with more pronounced inflammation, necrosis, and pulp disorganization. For pulpotomy, HPN and PRF seemed histologically to be good substitutes for FC in the dog model.

Intramedullary bone tissue reaction of ion-releasing resin-modified glass-ionomer restoration versus two calcium silicate-based cements: an animal study

This comparative study was conducted to assess the intramedullary bone tissue reaction of an ion-releasing resin modified glass-ionomer cement with claimed bioactivity (ACTIVA bioactive resin) restorative material versus Mineral Trioxide Aggregate High Plasticity (MTA HP) and bioceramic putty iRoot BP Plus. Fifty-six adult male Wistar rats were assigned into 4 equal groups (14 rats each). A surgical intramedullary bi-lateral tibial bone defects were performed in rats of the control group I (GI) and left without any treatment to be considered as controls (n = 28). The rats of groups II, III and IV were handled as group I except that the tibial bone defects were filled with ACTIVA, MTA HP and iRoot BP, respectively. In all groups, rats were euthanized after one month and specimens were processed to histological investigation, SEM examination and EDX elemental analysis. In addition, semi-quantitative histomorphometric scoring system was conducted for the following parameters; new bone formation, inflammatory response, angiogenesis, granulation tissue, osteoblasts and osteoclasts. The clinical follow-up outcome of this study revealed the recovery of rats after 4 days post-surgical procedure. It was observed that the animal subjects returned to their routine activities, e.g., walking, grooming and eating. The rats showed normal chewing efficiency without any weight loss or postoperative complications. Histologically, the control group sections showed scanty, very thin, new bone trabeculae of immature woven type located mostly at the peripheral part of the tibial bone defects. These defects exhibited greater amount of thick bands of typically organized granulation tissue with central and peripheral orientation. Meanwhile, bone defects of ACTIVA group showed an empty space surrounded by thick, newly formed, immature woven bone trabeculae. Moreover, bone defects of MTA HP group were partially filled with thick newly formed woven bone trabeculae with wide marrow spaces presented centrally and at the periphery with little amount of mature granulation tissue at the central part. The iRoot BP Plus group section exhibited an observable woven bone formation of normal trabecular structures with narrow marrow spaces presented centrally and at the periphery showed lesser amount of well-organized/mature granulation tissue formation. Kruskal Wallis test revealed total significant differences between the control, ACTIVA, MTAHP and iRoot BP Plus groups (p < 0.05). Meanwhile, Mann–Whitney U test showed significant difference between control and ACTIVA groups, Control and MTA HP groups, control and iRoot BP Plus groups. ACTIVA and MTA HP groups, ACTIVA and iRoot BP Plus (p ˂ 0.05) with no significant difference between MTA HP and iRoot BP Plus (p > 0.05). The elemental analysis outcome showed that the lesions of the control group specimens were filled with recently created trabecular bone with limited marrow spaces. EDX tests (Ca and P analysis) indicated a lower degree of mineralization. Lower amounts of Ca and P was expressed in the mapping analysis compared with other test groups. Calcium silicate-based cements induce more bone formation when compared to an ion-releasing resin modified glass-ionomer restoration with claimed bioactivity. Moreover, the bio-inductive properties of the three tested materials are likely the same. Clinical significance: bioactive resin composite can be used as a retrograde filling.

Comparison of Efficacy of Resin-Modified Glass Ionomer and Composite Restoration in Inhibition of Secondary Caries in Primary Molars

Objective: To evaluate and compare clinical performance and caries inhibition of Resin modified glass ionomer cement and composite restoration in primary molars&#x0D; Study Design: Quasi-experimental study.&#x0D; Place and Duration of Study: Department of Operative Dentistry, Armed Forces Institute of Dentistry, Rawalpindi Pakistan, from Feb 2019 to Jan 2020.&#x0D; Methodology: Eighty-three patients fulfilling the selection criteria having at least one carious mandibular primary molar on both sides were divided by split-mouth design. Resin-modified Glass ionomer restorations were done on one side and termed Group-A, and Composite Restorations were done on the other side and termed Group-B. Each restoration was clinically evaluated regarding the appearance of secondary caries at 3, 6 and 12 months after placement by the same operator who performed the treatment.&#x0D; Results: A total of 166 conventional restorations were placed in the 83 children having carious mandibular primary molars, at least one on each side of the arch. The assessment of restorations, performed after six months, showed an 89.2% success rate of Resin modified Glass ionomer restorations and a 66% success rate of Composite Restoration. One year of follow-up showed an 80% success rate for Resin modified Glass ionomer restorations and 60% for Composite Restoration, as regards secondary caries; statistically significant differences were found in both groups.&#x0D; Conclusion: The study results showed that Resin modified Glass ionomer cement used to restore primary molars affected by caries performed better clinically than composite in assessing secondary caries.

Universal versus Glass Ionomer –Based Adhesive: Effect on Shear Bond Strength and Micro-Morphological Analysis of Resin Modified Glass Ionomer Restorative Material /Dentin Interface

Universal versus Glass Ionomer –Based Adhesive: Effect on Shear Bond Strength and Micro-Morphological Analysis of Resin Modified Glass Ionomer Restorative Material /Dentin Interface

Flexural Properties of Contemporary Bioactive Restorative Materials: Effect of Environmental pH.

This study investigated the effects of environmental pH on the flexural properties of ion-releasing restorative materials (IRMs), including giomer (Beautifil-Bulk Restorative - BB), alkasite (Cention N - CN), bioactive composite (Activa - AB) and resin-modified glass ionomer (Riva Light Cure -RV) restoratives. A bio-inert resin-based composite (Filtek Bulk-fill Posterior - FB) served as the control. Stainless steel molds were used to fabricate 40 beam-shaped specimens (12mm × 2mm × 2mm) for each material. The specimens were finished, measured, and randomly distributed into four groups (n=10) and immersed in aqueous solutions of pH 3.0, pH 5.0, pH 6.8, and pH 10.0 at 37°C for 28 days. Specimens were then subjected to a uniaxial three-point bending flexural test with a load cell of 5 KN and a fixed deformation rate of 0.5 mm/min until fracture occurred. Flexural modulus and strength were statistically analyzed using analysis of variance/Dunnet T3's test (p=0.05). Mean flexural modulus varied from (2.40±0.41 to 9.65±1.21 GPa), while mean flexural strength ranged from (21.56±2.78 to 163.86±13.13 MPa). Significant differences in flexural properties were observed among the various pH values and materials. All materials immersed in artificial saliva (pH 6.8) presented the highest flexural properties, except AB. The flexural strength of AB was significantly better when exposed to acidic environments. FB had better flexural properties than IRMs after exposure to a range of environmental pH values.

Evaluation of the Masking Effect of Different Glass Ionomer Restorations following Silver Diamine fluoride and Potassium Iodide Application: An In Vitro Study

Abstract Objectives This is an in vitro study that aimed to evaluate the ability of different glass ionomer restorations to mask the discoloration produced following silver diamine fluoride (SDF) only and after potassium iodide (KI) application. Materials and Methods Thirty-six extracted human adult posterior teeth were collected. Box-shaped cavities (4 × 2 × 2 mm3) were prepared along the cementoenamel junction. Specimens were randomly divided into two major groups according to the materials applied under the restorations group (A) 38% silver diamine fluoride (SDF) followed by immediate application of potassium iodide (KI), group (B) 38% silver diamine fluoride (SDF) only. Each group was further subdivided according to the restorative material applied as follows (n = 6): subgroup (I) zirconia reinforced glass ionomer, subgroup (II) resin-modified glass ionomer restoration, and subgroup (III) high viscous glass ionomer restoration. Color assessment of all specimens was performed using a reflective spectrophotometer. Specimens' color was assessed color of normal dentin then assessed immediately after application of SDF (group A) and after application SDF + KI (group B) with the respective restorative material used. Statistical Analysis Data showed parametric distribution and variance homogeneity and were analyzed using one-way analysis of variance followed by Tukey's post hoc test. Results Intergroup comparisons showed that for SDF and SDF + KI samples, there was a significant difference between the different restorative materials (p &lt; 0.001). For glass ionomer, SDF samples had significantly higher color change value than SDF + KI (p &lt; 0.001), while for RMGI and zirconia reinforced glass ionomer, SDF + KI samples had significantly higher value (p &lt; 0.001) although zirconia reinforced glass ionomer showed the least color change following SDF (6.00 ± 2.74). Conclusion Within the limitations of this study, we could conclude that using zirconia reinforced glass ionomer could have a good masking effect on discoloration produced by SDF. While the resin-modified glass ionomer restoration showed more discoloration and darkening effect even after using of KI. Also, using KI in combination with SDF had a good masking effect on discoloration that produced by SDF.

Evaluation of the Shear Bond Strength of Four Bioceramic Materials with Different Restorative Materials and Timings.

The objectives of this study were to evaluate the shear bond strength (SBS) of a resin composite (RC) and a resin-modified glass ionomer (RMGI) to four different bioceramic materials and to compare the effects of the immediate vs. delayed placement of restoration on the SBS. A total of 160 Teflon blocks and 40 blocks/material, were randomly filled with one of the bioceramic materials (NeoPUTTY®, NeoMTA2®, TotalFill® BC RRM™ Fast Set Putty, and ProRoot® MTA). The restoration was performed immediately or in a delayed time frame (after 7 days) using a Filtek™ Z350 XT Flowable composite (bonded to the bioceramic materials using Single bond universal 3M) or GC Fuji II LC® RMGI. The SBS test was performed at a crosshead speed of 1 mm/min, and the failure mode was evaluated under a digital microscope by one blinded examiner. One-way analysis of variance (ANOVA) with the Games–Howell post hoc test was used to compare the mean SBS between the groups. The mean SBS of the bioceramic materials to RC was significantly higher than to RMGI except for ProRoot MTA (p-value 0.65). The SBS values to RC were as follows: ProRoot MTA (7.64 MPa); NeoMTA2 (8.57 MPa) which was significantly higher than both NeoPUTTY (4.04 MPa) and TotalFill® BC RRM™ Fast Set Putty (4.38 MPa). For RMGI groups, ProRoot MTA showed the highest SBS (7.18 MPa), followed by NeoMTA2 (4.15 MPa), NeoPUTTY (1.62 MPa), and TotalFill® BC RRM™ Fast Set Putty (1.54 MPa). The delayed timing restoration showed a significantly higher SBS than the immediate, except for the immediate RMGI restoration with MTA. To conclude, the SBS of RC to the bioceramic materials was significantly higher than RMGI, except for ProRoot MTA. Both restorative materials had a significantly higher SBS to the MTA groups in comparison to premixed bioceramics. Delayed RC restoration had a higher SBS than immediate restoration. Similarly, delayed RMGI restoration had a higher SBS than immediate restoration with premixed bioceramic but not with MTA.

Microtensile Bond Strength of Resin Modified Glass Ionomer Restoration in Carious Primary Molars Pretreated With Silver Diamine Fluoride

Microtensile Bond Strength of Resin Modified Glass Ionomer Restoration in Carious Primary Molars Pretreated With Silver Diamine Fluoride

Microtensile Bond Strength of Resin Modified Glass Ionomer Restoration in Carious Primary Molars Pretreated With Silver Diamine Fluoride

Microtensile Bond Strength of Resin Modified Glass Ionomer Restoration in Carious Primary Molars Pretreated With Silver Diamine Fluoride

Evaluation Of Fluoride Uptake By Dentine Following Pretreatment With Silver Diamine Fluoride And Potassium Iodide Under Resin Modified Glass Ionomer Restoration Versus Resin Modified Glass Ionomer Restoration Alone In Carious Primary Molars: (In Vitro Study).

Evaluation Of Fluoride Uptake By Dentine Following Pretreatment With Silver Diamine Fluoride And Potassium Iodide Under Resin Modified Glass Ionomer Restoration Versus Resin Modified Glass Ionomer Restoration Alone In Carious Primary Molars: (In Vitro Study).

Effect of delayed light-curing on solubility, color stability, and opacity of Fuji II LC glass ionomer cement: original article

Objective: Resin-modified glass ionomer (RMGI) cements are among the commonly used restorative materials inlow stress-bearing areas and also for temporary restorations. The competition between acid-base reactions andlight polymerization reactions in delayed curing of RMGIs can affect their physical and mechanical properties,as well as their degree of conversion. Since solubility, color stability, and opacity are among the main physicalproperties affecting the durability and clinical service of RMGI restorations, this study aimed to assess the effectof delayed curing on solubility, color stability, and opacity of Fuji II LC RMGI. Material and Methods: This invitro, experimental study evaluated 80 Fuji II LC RMGI specimens (10 specimens per each in 4 groups) in termsof solubility, color stability, and opacity at 6 months later. Specimens were cured immediately or were curedwith 1, 5 and 10 min delay. Results: Maximum solubility and minimum change in opacity and color stabilityat 6 months were noted in the group with delayed curing by 10 min. A significant difference was noted in thesolubility of specimens cured after 10 min and 1 min. Significant differences were also noted in the opacity andcolor stability of specimens cured after 10 min and all other groups (P &lt; 0.05). Conclusion: Delayed curingby 1 min decreased the solubility of RMGI specimens compared with immediate curing or curing after 5 min.Although this difference did not reach statistical significance. Color stability and changes in opacity are mainlyinfluenced by the acid-base reactions rather than polymerization reactions.KEYWORDSGlass Ionomer cement; Fuji II LC cement; Solubility; Color; Opacity.

Impact of direct restorative dental materials on surface root caries treatment. Evidence based and current materials development: A systematic review.

This systematic review provides an update on the development and efficacy of direct restorative dental materials for root caries interventions from in vitro and clinical studies. PubMed, Embase, and Web of Science were searched using specific MeSH keywords. Full articles from September 1990 to October 2021 were collected. Additional articles were identified by reference retrieval and manual searching. Studies not related to restorative materials for root caries treatment, case reports, non-original articles, and/or articles not written in English were excluded. Bias risk assessment was performed for the clinical studies. Forty-two articles (eleven clinical studies and thirty-one in vitro studies) were included for analysis. Most in vitro studies indicated an excellent cariostatic effect of glass ionomer cement. Resin-modified glass ionomer restorations also presented reduced recurrent caries activity but had a lower efficacy than glass ionomer cement restorations. For composite resin restorations, the main material development strategies are to strengthen the tooth structure and integrate antimicrobial activity. The clinical studies offered limited data, so the most appropriate material for surface root caries treatment is still inconclusive. However, atraumatic restorative treatment (ART) is an alternative treatment for patients with limiting conditions. Further clinical studies are required to confirm the efficacy of bioactive materials.

WITHDRAWN: Impact of riboflavin and curcumin mediated photodynamic therapy and Er,Cr:YSGG on microleakage of class V resin glass ionomer restorations in permanent molar teeth

The present study aimed to evaluate the impact of PDT using curcumin and riboflavin as photosensitizers and Er,Cr:YSGG on microleakage in class V RMGIC restorations in permanent teeth. Eighty permanent molars were investigated and randomly divided into 4 groups: control group: resin-modified glass ionomer restoration with no treatment, R-PDT: PDT with riboflavin, Cu-PDT: PDT with curcumin (Cu) and, Er,Cr:YSGG: laser application. All the teeth in each group were restored with the help of RMGIC. The samples were dipped for 24 h in 0.5 % Fuchsine solution, and subsequently fixed in acrylic resin-based molds. Microleakage scores were estimated considering both cervical and occlusal boundaries. Intergroup comparisons were made at each margin, and intragroup comparisons made at the cervical and occlusal margins. The Shapiro Wilk test was used to check the normality of the values. Whereas, the analysis of data was conducted using SPSS version 25 via the Kruskal-Wallis and Wilcoxon tests. P < 0.05 was contemplated to be statistically important. A high frequency (95%) of the enamel walls were not penetrated when subjected to treatment with R-PDT, followed by Cu-PDT and Er,Cr:YSGG. The highest amount of microleakage was observed (55%) Cu-PDT at the site of the cavity near the cementum. The least amount of microleakage was observed in the control group. A statistically significant difference in microleakage was noted at the cervical wall (p=0.015), while no significant difference was seen at the occlusal wall (p=0.789) between the groups. A significant difference was noted at the cervical wall between the control and R-PDT group (p=0.021) and Cu-PDT group (p=0.005), respectively. A significant difference in microleakage was observed when occlusal was compared with cervical walls within each group (p<0.05). Photosensitizers using riboflavin and curcumin may reduce the microleakage within the enamel surface restored with RMGIC in class V lesions that may not interfere with bonding. However, extreme caution should be taken while considering riboflavin and curcumin for class V RMGIC restorations extending to cementum surface.

Post-operative pain after 38% silver diamine fluoride application in primary molars with deep caries versus interim restorative therapy: A randomized pilot study

Aim: To compare the post-operative pain after application of Silver Diamine Fluoride (SDF) 38% in cavitated primary molars, in relation to Interim Restorative Therapy (IRT).Design: The study was performed on 20 carious primary molars in children aged 4-6 years attending the clinic in Pediatric Dentistry and Dental Public Health Department- Faculty of Dentistry -Cairo University. Partial excavation of caries on the walls of the cavity was performed then in group (A) SDF was applied in two visits with one-week interval, and finally Resin Modified Glass Ionomer Restoration (RMGI) was applied to the cavity. While, in group (B) Resin Modified Glass Ionomer restoration was applied immediately after partial caries excavation. Clinical and radiographic examinations were performed at three and six month’s follow-up periods for both groups.Results: In both groups, 100% of patients had no complications at three and six months follow up periods; except for 10% of patients experienced failure of restoration at three months in group B. The results showed insignificant differences between groups regarding clinical and radiographic outcomes at both three and six months. Conclusions: Silver Diamine Fluoride and Interim Restorative Therapy were clinically and radiographically successful when used in primary molars with cavitated dentin carious lesions.

Sealing Ability of Three Different Surface Coating Materials on Conventional and Resin Modified Glass Ionomer Restoration in Primary Anterior Teeth: An In vitro Study

Introduction: Microleakage is an important property that has been used in assessing the success of any restorative material used in restoring a tooth. Immediate application of a surface coating agent is suggested to protect glass ionomer cement against moisture contamination and dehydration during early setting. Aim: To compare marginal microleakage of two different Glass Ionomer Cement (GIC)- Conventional GIC and Resin Modified GIC in primary anterior teeth using three surface coating materials. Materials and Methods: An in vitro study was conducted between January 2014 to October 2017 on freshly extracted 40 anterior primary teeth which were randomly assigned into two main groups (Fuji II GIC and Fuji II LC GIC) with four subgroups (control-no surface coating, A=GC Fují Varnish II, B=GC G-Coat Plus, C=Icon). A standardised Class V cavity preparation was prepared on the labial surface of each tooth. Specimens were coated with two layers of nail varnish, leaving a 1 mm window around the cavity margins and placed in a solution of Methylene blue Dye for 24 hour at 37°C. The teeth were sectioned longitudinally in a buccolingual direction of the restorations and evaluated under stereomicroscope to check extent of dye penetration. The results were analysed by ANOVA and Tukey’s post-hoc test (p≤0.05). Results: It was found that maximum microleakage was seen in group 1 (Fuji II GIC) as compared to group 2 (Fuji II LC GIC) and it was non-significant (p=0.53). Ascending order for mean microleakage for Group 1 was as follows: Control &gt;GC Fuji Varnish &gt;Icon DMG &gt;GC G-Coat and for Group 2: Control &gt;GC Fuji Varnish &gt;Icon DMG &gt;GC G-Coat. Icon when compared with Gc coat and Varnish also showed non-significant (p=0.137) difference in Group 2. Conclusion: All three different surface coatings can seal glass ionomer restorations. The GC G-Coat Plus has the least microleakage on Resin-Modified GIC (RMGIC) compared to the other surface coatings. This would aid the clinicians to make appropriate decision regarding the choice of material to be used for restoration and coating in anterior primary teeth.

Influence of Isolation Technique on the Survival of Resin-Modified Glass-Ionomer Restorations in Primary Molars: A 9-Months Randomized Controlled Trial

Objective: T o compare the survival of occlusal and occlusal-proximal restorations performed with resin-modified glass-ionomer cement (RMGIC) in deciduous molars using rubber dam and cotton rolls isolation . Material and Methods: Ninety-two patients were included and 200 deciduous molars with cavitated occlusal or occlusoproximal dentin caries lesions were randomized into two groups: cotton rolls (n = 100) and rubber dam (n = 100) and RMGIC restorations were placed. At baseline and in the follow-up visit, presence, severity and activity of caries lesions were registered. Two independent, blinded examiners evaluated the treated teeth clinically using the USPHS criteria and radiographically after 9 months. Descriptive analysis, survival curve (log-rank test) and Cox regression were performed to assess risk factors related to failure. Results: Out of the 179 teeth (92 cotton rolls group and 87 rubber dam group) evaluated at 9-month follow-up period. No lesion progression was observed radiographically. The overall treatment success rate was 85.47% (83.47% for cotton rolls and 87.35 rubber dam group). No significant difference between isolation methods was observed in the log-rank test (p = 0.16). Cox regression showed no risk factors related to failure . Conclusion: No difference was found in the survival of occlusal and occlusal-proximal restorations performed with RMGIC in deciduous molars using a rubber dam and cotton rolls isolation after a 9-month follow-up period.

Miller Class III root coverage with coronary tissue repositioning associate with conjunctive graft

Miller Class III root coverage with coronary tissue repositioning associate with conjunctive graft

Comparative Evaluation of Microleakage of Amalgam, High Viscosity and Resin-Modified Glass Ionomers as Restorative Materials in Primary Molars

&lt;p&gt;&lt;strong&gt;Background and Objective:&lt;/strong&gt; One of the major requisites of an ideal restorative material is excellent marginal seal. Microleakage has been identified as a significant clinical problem with filling materials. The objective of the study was to evaluate and compare the degree of microleakage of amalgam, high viscosity glass ionomer and resin-modified glass ionomer in primary molars.&lt;br /&gt;&lt;strong&gt;Methods:&lt;/strong&gt; A total of 99 human non-carious primary molars that were liable to exfoliate within the next six months were selected. Standardized Class I cavities were prepared on occlusal surfaces of molars and randomly filled with either Amalgam (Aristaloy 21), High Viscosity Glass Ionomer (Ketac Molar) or ResinModified Glass Ionomer (GC Fuji II LC). The teeth were divided into nine groups (n=11 each) on the basis of filling material used and time of restored tooth extraction viz. one week, six weeks and twelve weeks. After immersion in a 2% methylene blue dye solution for 24 hours, the teeth were sectioned buccolingually in an occluso-apical direction through the middle of the restoration. The specimens were then examined under&amp;nbsp;&lt;br /&gt;stereomicroscope at 30X magnification. Statistical analyses were performed with ANOVA and Tukey&amp;rsquo;s test&amp;nbsp;&lt;br /&gt;at 5% level of significance.&lt;br /&gt;&lt;strong&gt;Results:&lt;/strong&gt; Amalgam restorations had significantly less microleakage as compared to the high-viscosity glass ionomer and resin-modified glass ionomer restorations. High-viscosity glass ionomer restorations were superior in resisting microleakage than resin-modified glass ionomers. The restorative materials used can be arranged in their sealing ability from least to severe microleakage as: Amalgam &amp;lt;High-viscosity glass ionomer &amp;lt;Resin-modified glass ionomer.&lt;br /&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;Amalgam restorations showed less microleakage as compared to high-viscosity and resinmodified glass ionomer restorations. Amalgam may preferably be used as a restorative material of choice&amp;nbsp;&lt;br /&gt;for primary molars.&lt;/p&gt;

Assessment of Bioactive Resin-Modified Glass Ionomer Restorative as a New CAD/CAM Material. Part I: Marginal Fitness Study

The objective of this in vitro study was to evaluate and compare the marginal fitness of monolithic crowns fabricated from a newly developed bioactive CAD/CAM resin block and reinforced resin CAD/CAM block pre-and post-cementation with adhesive and self-adhesive resin cements. Bioactive CAD/CAM block were fabricated from ACTIVA BioACTIVE-RESTORATIVE (Pulpdent Corporation, USA) using a clear rectangular Teflon mold. Thirty-two human maxillary first premolar teeth were prepared to receive full crowns then divided into two main groups of 16 teeth each according to the type of block used to fabricate the crowns: Group A: crowns fabricated from the bioactive resin block, Group B: crowns fabricated from reinforced composite block (BRILLIANT Crios, Coltene). Each group was then subdivided into two subgroups according to the type of resin cement used for cementation, Subgroups (A1, B1): RelyX Ultimate cement, Subgroups (A2, B2): ACTIVA BioACTIVE-cement. The prepared teeth were scanned using CEREC Omnicam digital intra-oral and the crowns were then designed using CEREC Premium software (version 4.4.4) and milled using CEREC MC XL milling unit. The marginal gap of each crown was measured before cementation at four points on each tooth surface using a digital microscope at a magnification of 230x. Each crown was then cemented on its respective tooth according to the manufacturers’ instructions of each cement, and the marginal gap was measured again at the same aforementioned points. The results of this study showed that the marginal gap of all groups are below the clinically acceptable limit. Meanwhile, the marginal gap of the crowns fabricated from both block types increased significantly after cementation with both types of cement. Pre-cementation, student’s t-test revealed that there is no statistically significant difference in the marginal gap of crowns fabricated from both block types (p&gt; 0.05). Post-cementation, a statistically highly significant difference was seen between both block types with both types of cement (p&lt;0.01). From the results of this study, the newly developed bioactive resin block seems a promising material for CAD/CAM applications in terms of marginal fitness.