Light-cured Glass Ionomer Cement Research Articles

Comparative evaluation of microleakage of self-cure, dual-cure, and light cure glass ionomer cement in a simulated oral environment - an invitro study

Background. Pediatric dentistry utilizes various restorative materials wherein the durability and longevity of these restorations hinge on the maintenance of an intact marginal seal to prevent microleakage and its associated complications. Consequently, this study aims to assess the microleakage of self-cure, dual-cure, and light-cure glass ionomer-based cements utilizing a stereo microscope. Materials and Methods: Sixty therapeutically extracted deciduous molars were taken for the study. The restorative materials used for the studies were self-cure Glass Ionomer cement (Chemfil Rock and GC Fuji IX GP Fast GIC), dual cure Glass Ionomer cement (EquiaForte and Ionolux GIC), and light cure Glass Ionomer cement (GC Fuji II and Ketac N 100 GIC). All samples were stored in commercially available artificial saliva for 20 days to simulate the oral environment. The samples were immersed in Rhodamine B dye for 24 hours, and microleakage was evaluated using a Stereo microscope. Data were tabulated and statistical analysis was done. p < 0.05 is considered significant Results: In the individual assessment of glass ionomer-based cement, Ketac N100 GIC exhibited the lowest microleakage, whereas Ionolux displayed higher levels of microleakage. Conclusion: In terms of the curing method, light-cure glass ionomer cement demonstrated the least microleakage compared to both dual-cure and self-cure glass ionomer cement.

Shear Bond Strength of Chemical and Light Cured Glass Ionomer Cements Bonded to Resin Composite

The purpose of this study was to compare the shear bond strength of chemically cured (Conventional) glass ionomer cement and light cured (Resin modified) glass ionomer cement to resin composite and to evaluate the effect of acid etching of the glass ionomer cements on the shear bond strength.Forty acrylic molds were prepared, a hole (6×2) mm was prepared in each mold to retain the glass ionomer cements (GICs). The samples were divided into two main groups. The first group were filled with Conventional GIC and the second group were filled with Resin modified glass ionomer cement (RMGIC), then each group were subdivided into two subgroups, the first subgroup were acid etched and the second subgroup were left without etching. The bonding agent applied to the demarcated bond area on the GIC surface, the composite resin cylinders were built up over the GIC base. The samples were stored for one week in deionized water then thermocycled. The samples then tested for shear bond strength (SBS) using universal testing machine.The result shows that Independent samples T-test used for statistical analysis. The result showed that RMGIC significantly had higher SBS than conventional GIC. No statistical difference was shown in SBS between subgroup etched and without etching for RMGIC, but the conventional GIC showed significantly higher SBS in subgroup without etching than with etching.This study Conclude that the SBS of RMGIC to resin composite was significantly higher than that of conventional GIC. Acid etching the GIC surface did not improve the SBS of GICs to resin composite.

Color Stability of Pediatric Restorative Material Over Pediatric Drug Formulation.

To investigate the color stability of light-cured (LC) restorative material in different pediatric drug formulations. Two distinct restorative materials, specifically LC resin and LC glass ionomer cement (GIC), were employed to create 88 disc-shaped specimens. These comprised 44 specimens fabricated from each material. Each specimen had a diameter of 5 mm and a height of 3 mm. To conduct the experiment, specimens were randomly allocated into four experimental groups, each containing 11 specimens made of each material. This division was accomplished through the use of a stratified random sampling method.The five experimental groups and their respective liquid medications were as follows: Group 1 - montelukast sodium and levocetirizine dihydrochloride syrup, Group 2 - cefixime, Group 3 - sodium valproate, and Group 4 - metronidazole. To ensure thorough exposure to the medications, all samples underwent a two-minute agitation cycle, which was repeated every 12 h over the course of one week. Following the immersion period, the color stability of all specimens was assessed using a spectrophotometer. The data obtained from the color stability measurements were subjected to statistical analysis using one-way analysis of variance (ANOVA), followed by a post hoc test. The aim was to determine whether significant differences in color stabilitywere observed among the groups studied. The mean values and standard deviations of ΔE were calculated. The highest values of ΔE were observed in Group 3 (4.70 ± 1.89), followed by Group 4 (4.04 ± 2.10). Conversely, the lowest ΔE values were observed in Group 2 (3.23 ± 2.02) and Group 1 (3.24 ± 2.31). The calculated p-value was 0.298, and the F-value was 1.269. This study concludes that both restorative materials, LC composite and LC GIC, are susceptible to discoloration. Sodium valproate exhibited the greatest staining effect on both materials. Conversely, cefixime had the least impact on the color of the LC composite, whereas montelukast had the least effect on the color of LC GIC.

A Comparative Evaluation of Enamel Surface Roughness of Two Different Bonding Adhesives After Debonding With Atomic Force Microscopy

Introduction The debonding procedures should restore the enamel surface to its pre-treatment state as much as possible after removing orthodontic attachments and all remaining adhesive remnants from the surface of the tooth. The orthodontic attachments are bonded commonly by a light-cured composite system. Light-cured glass ionomer cement has been developed as an alternative to the composite as a bonding agent for orthodontic brackets. There are different methods for cleaning the residual adhesive after the removal of orthodontic attachments. The study aims to evaluate and compare the enamel surface roughness of teeth between two different adhesive systems - light cure composite and glass ionomer cement adhesives - after debonding followed by the removal of resin remnants with a tungsten carbide (TC) bur.A null hypothesis is proposed that there exists no difference in the enamel surface roughness between the two adhesive systems. Materials and methods The test sample of 40 freshly extracted human premolar teeth(n = 40) for orthodontic purposes was taken up for this in vitro study based on the inclusion and exclusion criteria. The sample was randomly assigned into two equal groups, with metal brackets bonded in Group-I (n = 20) by light cure adhesive (Trans bond XT, 3M Unitek, Monrovia, CA)and Group-II(n = 20) with light glass ionomer cement (GC Fuji Ortho LC, Tokyo, Japan). All samples were stored in water at room temperature for 24 hand brackets were debonded with a debonding plier. The removal of cement adhesive remnants was performed with a TC bur with a low-speed handpiece. The three surface roughness parameters, average roughness (Ra), root mean square roughness (Rq), and maximum roughness depth (Rmax), were measured at T1 (before bonding) and at T2 (after debonding and finishing) and the values were compared. The mode of bond failure was assessed by a modifiedadhesive remnant index (ARI) and the time required for the clean-up of adhesive was also noted. Statistical analysis The continuous quantitative data were statistically analyzed usingSPSS Statistics v. 25.0 (IBM Corp., Armonk, NY). Student's independent t-test/independent-samples t-test is an inferential statistical test for analyzing the difference between the two groups. Paired t-test was used for comparison within the group. The ARIbetween the groups was analyzed by a chi-square test. The probability (p) value for statistical significance was 0.05 or less for the difference between any two groups for all the analytical tests. Results A comparison of enamel surface roughness before bonding and after debonding for both groups revealed that there was a statistically significant difference within each group. The surface roughness values of composite resin- Ra (98.75 ± 0.96), Rq (120.38 ±1.06), Rmax (650.14 ± 1.12) - and glass ionomer cement group - Ra (98.75 ± 0.96), Rq (62.76 ± 1.32), Rmax (434.36 ± 1.60) - showthat there was a statistically significant difference between the groups with p <0.01. Conclusion There was a significant increase in the surface roughness of enamel after debonding of brackets and finishing with a TC bur with both the light cure and the glass ionomer cement adhesive systems. The light cure group showed more enamel surface roughness when compared to the glass ionomer cement group. In this study, the null hypothesis was rejected as there is a significant difference between the groups tested.

Reinforcement of endodontically treated teeth by different intraorifice barrier materials

Background: Fracture incidences are more common in teeth with endodontic therapy and hence endodontic therapy should aim toward the reinforcement of such teeth by placing various restorative materials. Aims: Comparative evaluation of different intraorifice barrier material on strengthening the fracture resistance of teeth requiring endodontic therapy. Methods: Sixty extracted human mandibular premolars with one root were divided into four groups (n = 15); Group 1- Light cured Glass ionomer cement, Group 2 - Nanohybrid composite (NHC), Group 3 - High copper amalgam, Group 4-Control. Decoronation of specimens was done to a standardized length of 14 mm and was instrumented up to International Organization for Standardization (ISO) #30 size master apical file. Gutta percha was used to carry out the obturation by the cold lateral compaction technique. With the exception of the control group, elimination of 3 mm obturation from the coronal portion was done and intraorifice barrier materials were placed. Universal Testing Machine was used for testing fracture resistance. Statistical Analysis: Analysis of variance was applied to analyze the data obtained and pairwise comparison was done by post hoc tukey's test (P < 0.05). Results: Better resistance to fracture incidence was seen with NHCs. Control group presented the least values. Conclusion: On placement of intraorifice barrier materials in teeth with endodontic therapy, there was a reduction in fracture incidence.

Influence of Selected Restorative Materials on the Environmental pH: In Vitro Comparative Study

In dental caries treatment, it is worth using such restorative materials that may limit plaque accumulation. The pH of the filling seems to be an important factor affecting the potential bacterial colonisation. Our study aimed to assess how selected restorative materials influence the environmental pH. A total of 150 specimens (30 of each: Ketac Molar, Riva LC, Riva SC, Filtek Bulk Fill, and Evetric) were placed in 100 sterile hermetic polyethene containers with saline and stored in 37 °C. The pH of each sample was measured using the electrode Halo HI13302 (Hanna Instruments, Poland) at specific points in time for 15 days. The initial pH levels were significantly lower for glass ionomer cements (3.9–4.7) compared to composites (5.9–6.0). With time, the pH increased for samples with glass ionomer cements (by nearly 1.5), whereas it decreased for samples with composites (maximally by 0.8). In the end, all materials were in the pH range between 5.3 and 6.0. The highest final pH was obtained with Ketac Molar at about 5.9. Double samples had lower pH values than single samples, irrespective of the type of material. In conclusion, immediately after application, restorative materials decreased the environmental pH, especially light-cured glass ionomer cements. For glass ionomers, within two weeks, the pH increased to levels comparable with composites.

Comparing Bacterial Leakage of Three Intraorifice Barrier Sealing Materials against Enterococcus faecalis and Proteus vulgaris

The purpose of this in vitro study was to evaluate the intraorifice sealing ability of light-cured glass-ionomer cement (LC-GIC), Tetric N-Flow, and ProRoot mineral trioxide aggregate (MTA) against Enterococcus faecalis and Proteus vulgaris. Crowns of the eighty human mandibular teeth were decapitated. Working length determination was performed, after which cleaning and shaping were carried out. A uniform orifice diameter of 1.3 mm, at its widest point, was made. Once instrumentation was completed, the canals were irrigated and then obturated. A heat carrier was used to remove gutta-percha to the depth of 3.5 mm. Samples were then divided into a control group (Group 1) with no barrier, and three groups, namely, Group 2, Group 3, and Group 4, were restored with the LC-GIC, Tetric N-Flow, and ProRoot MTA, respectively. The groups were further subdivided into Subgroup A for checking bacterial leakage against E. faecalis and Subgroup B, against P. vulgaris. All samples were subjected to the bacterial leakage test and observed daily for the appearance of turbidity after which statistical analysis was performed. Group 1 showed leakage in, as early as, 3 days. The longest time for the turbidity to appear was shown by Group 4 with an average of 31 days. The mean number of days for turbidity to appear in Group 2 and Group 3 was 23 and 24 days, respectively. Group 4 showed the best intraorifice sealing ability with a significant difference. The teeth with an intraorifice coronal seal had better protection against microbial leakage. Among all materials used, the ProRoot MTA showed the best intraorifice sealing ability. Use of the ProRoot MTA promises long-term results in the endodontically treated teeth as compared with other materials.

An in vitro evaluation of effect of internal matrices of hydroxyapatite and calcium sulfate on sealing ability of mineral trioxide aggregate and light cured glass Ionomer cement when used as furcation repair materials

An in vitro evaluation of effect of internal matrices of hydroxyapatite and calcium sulfate on sealing ability of mineral trioxide aggregate and light cured glass Ionomer cement when used as furcation repair materials

Comparative in vitro Assessment of Tooth Color Change under the Influence of Nano Fast Cement and MTA.

Statement of the Problem: Tooth color changes followed by treatment with bioceramic materials are always a matter of concern.Purpose: The aim of the present in vitro study was to compare tooth discoloration that occurs in human teeth filled with ProRoot WMTA (DENTSPLY Tulsa Dental Specialties, Tulsa, OK) and those filled with Nano Fast Cement (NFC) over the course of 3 months.Materials and Method: In this experimental study, Thirty human intact premolars were obtained. The roots of all teeth were removed by a horizontal cut about 2 mm below the cementoenamel junction. The pulp tissues were removed using a barbed broach (Mani, Tokyo, Japan).The teeth were randomly divided to 3 groups (n= 10) including the control (no material), ProRoot WMTA and NFC. The experimental materials were condensed into the crowns and the teeth ends were sealed with light-cure glass ionomer cement (GC Corporation, Tokyo, Japan). The color was assessed at TBL (baseline; after preparation of the cavities but before placement of the materials), TPO (immediately after placement of the filling material and provisional restoration), T4 (after 4weeks of storage), and T12 (after 12weeks) of storage.Results: The discoloration was evident in all teeth, immediately (TPO) after applying MTA and NFC. The highest ΔΕ was noted in WMTA at 12 weeks, followed by NFC; however, there was no significant difference between the discolorations induced by these two materials. Conclusion: Similar levels of clinically observable tooth discoloration were detected by using either WMTA or NFC.

The use of carbonate apatite bioglass cement as pulp capping material examined from reparative dentin

Root canal infection potentially develops to periapical infection as a result of opening of pulp chamber as a pathway for irritants to periapical area. Proper pulp capping procedure can be done to prevent root canal infection by preserving the vitality of the pulp and inducing reparative dentin. Generally, calcium hydroxide (Ca(OH2)) is used as pulp capping material although it stil3Ap) and CO3Ap bioglass cement are bioceramic materials proven for their ability to form new bone structure upon a research on bone tissue. These materials have better mechanical strength than Ca(OH2) and have the ability to set in humid environment similar to the body’s physiological condition. This study was a preclinical trial of CO3Ap and CO3Ap bioglass cement as pulp capping material. The materials were applied on a perforation site of 24 Wistar rat teeth, divided into 4 groups of different treatments, negative control (no treatment), positive control (Ca(OH2)), CO3Ap, and CO3Ap bioglass, respectively. Following the application of the pulp capping materials, the perforation sites were covered with light-cured glass ionomer cement. Evaluation of reparative dentin was performed after 21 days, where the rats were euthanized, and histopathological specimens were stained using hematoxylin and eosin. The results of the study revealed that dentinal bridge was formed on all the treatment and positive control groups (p=0.000) but not on the negative control. We concluded that CO3Ap as well as CO3Ap bioglass cement have the ability to induce the formation of reparative dentin, therefore both materials can be considered as pulp capping material for open pulp or thin dentin condition on pulp chamber roof.

Effects of magnetic resonance imaging on the microleakage of five restorative materials: An in vitro study

The objective of this study was to assess the effects of 3 T magnetic resonance imaging (MRI) on the microleakage of 5 restorative materials. In total, 100 maxillary molars were randomly assigned to 5 groups (n=20) for restoration with 5 different materials: amalgam, light-cured glass-ionomer cement, feldspathic porcelain fused to metal, pressed lithium disilicate glass ceramic, and composite resin. In each group, 10 specimens were subjected to MRI, and 10 specimens served as controls with no MRI exposure. Standardized class V cavities were prepared with occlusal margins terminating in enamel and gingival margins terminating in dentin. Microleakage penetration at the enamel and dentin margins was calculated for each group. A chi-square test was used for intergroup comparisons. Statistical significance was established at P < .05. Microleakage penetration did not differ significantly between specimens subjected to MRI and the controls for any restoration (P ≥ .362 for the enamel margin, P ≥ .067 for the dentin margin) or between specimens treated with different restorative materials (P ≥ .355). No significant differences in microleakage were discovered between the enamel and dentin margins of any of the restorative groups (P ≥ .236). MRI had no effect on the microleakage of the 5 restorative materials.

EFFECT OF DIFFERENT CAVITY LINING MATERIALS ON MARGINAL SEALING OF PACKABLE COMPOSITE RESIN RESTORATIONS- AN IN VITRO STUDY.

ABSTRACT:&#x0D; “AIM: To assess the effect of three lining materials; flowable composite, flowable compomer, and light-curing glass ionomer cement (LCGIC) on microleakage in Class V restoration using packable composite restorations.&#x0D; MATERIALS AND METHODS: A standardized class V cavity was prepared on buccal surface of 40 young premolar teeth with the cervical margin extending 0.5 mm below the cementoenamel junction, into the dentin. All the samples were randomly divided into 4 groups according to the lining material used: Group I- Control; Group II- flowable composite; Group III- LCGIC and Group IV- flowable compomer. The restored teeth were thermocycled and immersed in 2% methylene blue solution for 24 hours. Each tooth was then sectioned along buccolingual direction. The dye penetration of the occlusal and gingival margins of each section was evaluated by a single observer using a stereomicroscope and statistically analyzed using Kruskal Walis Test and Mann-Whitney U Test.&#x0D; RESULT: Maximum dye penetration score for Group 1, Group 2 was 3 and Group 3, Group 4 was 1. (p&lt;0.05)&#x0D; CONCLUSION: Flowable compomer and light cure glass ionomer cement as intermediate lining material can reduce microleakage under packable composite.&#x0D; Keywords: Compomer, flowable composite, light-curing glass ionomer cement, microleakage, packable composite.”

An antibacterial dental light-cured glass-ionomer cement with improved hardness

An antibacterial dental light-cured glass-ionomer cement has been developed and evaluated. An antibacterial furanone derivative was synthesized and covalently attached onto the surface of alumina filler particles. The formed antibacterial fillers were then mixed into a light-curable glass-ionomer cement formulation. Surface hardness and bacterial viability were used to evaluate the modified cements. Effects of coated furanone moiety content on the modified fillers, modified alumina filler particle size and loading, and total glass filler content were investigated. Results showed that increasing antibacterial furanone content, modified particle size and loading, and total glass filler content generally increased surface hardness. Increasing furanone moiety, filler loading and total filler content increased antibacterial activity. On the other hand, increasing particle size decreased antibacterial activity. The leaching tests indicate that the modified experimental cement showed no leachable antibacterial component to bacteria and cells

Calcium silicate cement interface with restorative materials through layering after different time intervals.

The aim was to evaluate the interfacial characteristics of Biodentine, CEM Cement, and ProRoot MTA when restored with different final restorative materials after different time intervals. Biodentine, CEM Cement and ProRoot MTA were layered with amalgam, composite resin or light cure glass ionomer cement. Layering was done either immediately, 24 or 72h after cement placement. The interface of cements with restorative materials was characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) after separation. Vickers surface microhardness test was also performed on the interface. Statistical analysis included two-way Anova, Dunnett T3, and Tukey HSD. The significance level was set at P < 0.05. The highest microhardness values were seen when restorative materials were layered after 24h in the case of Biodentine, and after 72h in the case of CEM Cement and ProRoot MTA. In ProRoot MTA no significant difference was seen in the microhardness when layered with different restorative materials regardless of the time of layering. In immediate layering, Biodentine exhibited the highest microhardness values. Both immediate and delayed layering resulted in element transfer between calcium silicate cements (CSCs) and restorative materials. Deposition and depletion of element occurs subsequent to layering of restorative materials on CSCs. When immediate layering is necessary, Biodentine may be a better option compared to other CSCs evaluated.

Evaluation of marginal sealing quality of restorations with low shrinkage composite resins

BackgroundThis study compared the quality of marginal sealing in the gingival wall of class II preparations of two low-shirinkage resins of the bulk fill type with a conventional resin isolated or associated with a glass ionomer cement (GIC). Material and Methods40 human molars were divided into 4 groups and 80 occlusal-mesial and occlusal-distal restorations were performed with the following materials: SureFil SDR flow, Filtek Bulk Fill Posterior, Z250 resins and Riva Light Cure GIC. 40 restorations were evaluated in Scanning Electron Microscopy (SEM) with Elemental Microanalysis Spectrometry (EDS) initially and the remainder after a period of 6 months of aging in a 37 ± 5°C oven. An average of the silver penetration at each restoration was obtained in the two evaluations and the results were statistically analyzed in a descriptive and inferential way, through the paired t-Student and one-way ANOVA F-test. ResultsThere were no significant statistical differences between the materials with respect to silver nanoinfiltration, except for the Bulk Fill Posterior/3M ESPE resin compared to the GIC and conventional resin in the final evaluation. Conclusions The low shrinkage resins showed a similar behavior in relation to the marginal sealing quality observed in the GIC or composite resin with the incremental technique, also presenting the advantage of simplicity in the technique of confection of the restorations and reduction of the time of work. Key words:Resin composites, Bulk fill, dental restorations, marginal quality, adhesion.

PERBEDAAN ANGIOGENESIS PADA PULPA SETELAH APLIKASI EKSTRAK PROPOLIS DAN KALSIUM HIDROKSIDA

Background : Propolis is a resinous hive product collected by bees ( Apis Mellifera ) from tree buds and mixed with secreted bee wax in order to avoid bacterial contamination in the hive, and also to seal it. Propolis is employed for the treatment of various infectious diseases because it is wellknown that is has antibacterial and anti-inflammatory properties. Calcium hydroxide was introduced to the dental profession in 1921 and has been considered the “gold standard” for direct pulp capping materials in the past decades. Aims :This research is to investigate the development of new blood vessels ( angiogenesis ) in rat's dental pulp following application of propolis extract and calcium hydroxide. Methods : There was 43 Strain Wistar rats of 8–16 week old and 200–250 grams in weight were used in this study. The rats were randomly divided into 6 groups. Pulp exposures were performed on the occlusal surface of right maxillary first molars. At the 1st and 4th groups, as the control group, without pulp capping paste. At the 2rd and 5th groups, pulp exposure was applied with propolis extract. And at 3th and 6th groups pulp exposure was applied with calcium hydroxide ,and the 7th group is negative control is a normal teeth. Pulp exposure was applied with propolis extract. After that, all of the cavities were filled with light cured glass ionomer cement as a permanent filling. Animals on the 1st, 2rd, and 3th groups were decaputed after 7x24 hour post pulp capping material application and were sent for histological examination which new blood vessels ( angiogenesis ) cells were present. And at the 4th, 5th, 6th groups were culled after 7x 24 hour post pulp capping material application and were sent for histological examination which new blood vessels ( angiogenesis ) evaluated were present. Result : All sample were histopathological examinated and data was statiscally analysed using one way ANOVA the histological analysis revealed that the development of the new blood vessels occurred in all group. The new blood vessels ( angiogenesis ) of propolis extract group was milder compared to the control and calcium hydroxide group, with statistical analysis showed significant difference (p &gt; 0.05). Conclusion: The development of new blood vessels is earlier happened in group capping material containing propolis and which show with reduce the amount of the new blood vessels in days 7 and 14 than the other group.

Clinical and Radiographic Success of Three Adhesive Restorative Materials in Primary Molar Proximal Lesions: A Randomized Clinical Trial.

Aim:The aim of this study was to evaluate and compare the clinical and radiographic success of primary molar proximal lesions in 4–8 years children restored with three adhesive restorative materials followed up for 12 months.Materials and Methods:This study was carried out on 102 primary molars of 51 children in the age range of 4–8 years. In all the participants, Class II lesions were restored and randomly allocated into three material groups as giomer group, nano-ionomer group, and light-cured glass-ionomer cement (LC-GIC) group based on the restorative material used. All the restorations were evaluated and scored according to federation dentaire internationale (FDI) criteria for clinical and radiographic success rate at 3, 6, and 12 months' interval. Data were formulated in a predesigned format and were subjected to statistical analysis using the Chi-square test and Fisher's exact test.Results:There was no statistically significant difference observed among the restorative material groups to all the properties of FDI criteria. The overall success rates of restorative materials at 3, 6, and 12 months' interval were as follows: giomer – 100%, 100%, and 94.1%; nano-ionomer – 97%, 94%, and 85.3%; and LC-GIC – 100%, 94%, and 88.2%.Conclusion:The highest clinical success rate was found for the giomer group followed by LC-GIC group and the least for the nano-ionomer group, whereas the highest radiographic success rate was found for giomer as well as LC-GIC group and the least for nano-ionomer group.

Perforation of the pulp chamber floor: repair with mineral trioxide aggregate, light-cured glass ionomer cement and light-cured calcium hydroxide

Perforation of the pulp chamber floor: repair with mineral trioxide aggregate, light-cured glass ionomer cement and light-cured calcium hydroxide

Evaluation of Carbonate Apatite Cement in Inducing Formation of Reparative Dentin in Exposed Dental Pulp

Carbonate apatite (CO3Ap) cement is a biocompatible material with the ability to induce osteogenesis and is widely studied as the bone substitute material. The similarity of bone to tooth structure in their organic and inorganic composition offers a good prospect of the application of CO3Ap for regeneration of dentin and pulp tissue repair. This study is a sequel of the previous study in the development of CO3Ap cement for dental application, particularly in pulp capping treatment. In this study, the CO3Ap cement is used to cover an exposed dental pulp in rats and histological evaluation was carried out to evaluate the formation of reparative dentin, which is one of the signs of positive pulp capping treatment outcome. The CO3Ap cement was made by combining 60% dicalcium phosphate anhydrous (DCPA) and 40% vaterite with 1 mol/L Na2HPO4 aqueous solution at liquid to powder ratio of 0.5 and conventional calcium hydroxide [Ca(OH)2], which is the golden standard for pulp capping material was used for control. The coronal part of dental pulp in Wistar Rat was exposed with a small dental bur until bleeding were visible. The CO3Ap cement was applied to the exposed pulp and covered with light cured glass ionomer cement. The same protocol was applied to the control groups using Ca(OH)2. The Evaluation of formation of reparative dentin was done in 3 weeks after application by histological observation. Reparative dentin was histologically visible for all samples in CO3Ap group, as well as in the Ca(OH)2 groups. None of the dental pulps were necrotic and the pulp showed no heavy chronic inflammation. The CO3Ap cement was able to maintain the vitality of the pulp with no sign of chronic inflammation. The formation of reparative dentin was observable in 3 weeks of evaluation. Investigation on other properties and in vivo studies in different types of perforation and animal are to be carried out for further development of this material in dental application.

The effect of cusp capping with composite resin on fracture resistance of premolars with prepared endodontic access cavities: An in vitro study

Introduction: The purpose of this study was to evaluate the effect of remaining dentinal wall thickness and the effect of remaining cusp height of endodontically treated premolars when restored with composite resin. Materials and Methods: Ninety premolars were divided into 4 test groups (n = 20) and 2 control groups (n = 5). In all groups, except the negative control group (sound teeth), standardized endodontic access cavities were prepared, pulp extirpated, mesioocclusodistal (MOD) cavities prepared and access sealed with Light Cure Glass Ionomer Cement (LC GIC). Test groups were divided as:- Cusp reduction for Groups I and II- 2.5 mm and for Groups III and IV- 1.5 mm. Dentinal wall thickness for Groups I and III- 1-1.5 mm and Groups II and IV- 2-3 mm. The groups were further subdivided into Subgroup A, restored with P60 and Subgroup B, restored with Herculite Precis. Positive control- only access cavity with no cusp reduction and restoration. Fracture resistance was assessed using Universal Testing Machine (UTM). Results: Highest fracture resistance was demonstrated by Group VI and least by Group V. Groups VI, II and I, showed statistically insignificant difference for both the composites (P > 0.05). Groups III and IV showed statistically significant difference only for Subgroup B. Conclusion: When the cusp reduction was 2.5 mm, dentinal wall thickness had no effect on the fracture resistance, for both the composites. When the cusp reduction was 1.5 mm and the remaining dentinal thickness was 1-1.5 mm, Herculite Precis showed inferior results to P60.