Papers by Keyword: Calcium Hydroxide

Abstract: Calcium hydroxide (Ca (OH)₂) is an intracanal medicament used as a disinfectant in cases of tooth inflammation with ad dubia prognosis. The success of root canal treatment depends on the ability of intracanal medicaments to eliminate pathogenic bacteria present in the walls of narrow and complex root canals by releasing calcium and hydroxyl ions at the closest contacts. This study aimed to evaluate the effect of particle size on the ability to penetrate Ca (OH)₂ in the coronal, middle, and apical root canals. Fifteen mandibular premolars extracted for orthodontic and periodontal purposes were collected and cut to produce root canals with a length of 12 cm. The root canals were then prepared with a Protaper SX-F3 needle and irrigated using a solution of 2.5% NaOCl, NaCl, and 17% EDTA as lubrication at each needle change. Ca (OH)₂ with different particle sizes in paste form was manipulated with distilled water at a concentration of 0.8 g/mL then the paste was applied to the prepared tooth root canals and covered with a temporary filling. The samples were then stored in an incubator at 37 °C for 7 days. Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDX) was performed on the transverse surfaces of the coronal 1/3, middle 1/3 and apical 1/3 of the tooth. The maximum penetration depth was evaluated by measuring the maximum distance between the dentin canal wall and Ca (OH)₂ present in the dentinal tubules. In all three zones, the Ca (OH)₂ nanoparticles had a greater penetration depth than the Ca (OH)₂ nanoparticles (P<0.001). In both groups, the penetration depth increased from the apical to the coronal section. All differences in the penetration test ability of the Ca (OH)₂ nanoparticles and Ca (OH)₂ microparticles at all depths of the surface. Ca (OH)₂ nanoparticles penetrate deeper into the dentinal tubules than Ca (OH)₂ microparticles do.

Abstract: Continuous cockle shell dumping in open areas has become a global problem which generate major environmental issues. The conversion of the wastes into value-added products is highly desirable and economic. This work aimed to investigate the influence of sol-gel processing parameter on the properties of the synthesized calcium hydroxide (Ca(OH)₂). In this study, cockle shell waste was used as calcium carbonate (CaCO₃) precursor in the preparation of Ca(OH)₂ via sol-gel method and the processing parameter varied was hydrochloric acid (HCl) concentration (0.5, 1.0 and 2.0 M). The cockle shell based CaCO₃ and the prepared Ca(OH)₂ powders were characterized by X-ray diffraction (XRD), Fourier transform infra-Red (FTIR), field emission scanning electron microscopy with energy dispersive X-ray (FESEM-EDX), X-ray fluorescent (XRF) and particle size analyzer (PSA). The XRD analysis indicates that the calcium carbonate obtained from cockle shell was mainly in the form of aragonite polymorph. Upon sol-gel processing, the analysis of the sample shows the presence of portlandite and small traces of aragonite in all samples suggesting an incomplete reaction of the hydrolysis process. Ca(OH)₂ powder prepared using 1M HCl yields the smallest particle size.

Abstract: The article presents experimental studies of the composite binders modification with basalt fibers waste. The introductory part provides studies overview of basalt fibers resistance in various aggressive environments. It was revealed that the most aggressive environment in relation to basalt fibers and other products based on them is alkaline. Also, it is promising to use their production waste as a modifying additive for building compositions. But in this case, the problems associated with leaching are equally relevant for each of the reinforcing components. The components characteristics and the test procedure are described and illustrated in the next section. The following are the results of determining the strength characteristics of samples obtained on a composite binder modified with basalt fibers and acid ash productions waste. Finally, a brief analysis and conclusions are presented to confirm the effectiveness of reducing the environment aggressiveness in relation to the basalt fibers production waste adding acidic ash to the composition.

Abstract: Recurrent endodontic infections of treated teeth are mainly linked to microbial persistency in the root canal system. Enterococcus faecalis is a bacterium that is often identified in these recurrent infections. Calcium hydroxide (Ca(OH)₂) is a widely used root canal medicament and is now being developed to be produced from natural materials. Ca(OH)₂, which is synthesized from natural limestone from Palimanan, Indonesia, has a structure similar to Ca(OH)_2, which is often used as a root canal medicament. The purpose of this study was to determine the antimicrobial property of Ca(OH)₂ paste synthesized from natural limestone compared to conventional Ca(OH)₂ paste. This study is an in vitro experimental study consists of 3 groups (n=24, namely, conventional Ca(OH)₂ paste, limestone synthesized Ca(OH)₂ paste, and saline as the negative control, for 2 intervals of time and evaluated by Total Plate Counting (TPC) method. Samples were mandibular first premolar root canal prepared by root canal preparation and contaminated with E. faecalis (ATCC 29212). The infected root canals of each group were treated by the medicaments, and samples from the root canals were taken on day 7 (n=4) and 14 (n=4). Results showed that both Ca(OH)₂ groups had antimicrobial activities against E. faecalis. The limestone Ca(OH)₂ paste group had the least amount of bacterial colonies on the 7^th day compared to other groups. In contrast, on the 14^th day, the conventional Ca(OH)₂ paste had the least bacterial colonies. It can be concluded that the Ca(OH)₂ paste synthesized from natural limestone has an antimicrobial effect on E. faecalis, the antimicrobial effect was higher on the 7^th day but decreases on the 14^th day, whereas the conventional Ca(OH)₂ had a higher antimicrobial effect on day 14 compared to day 7. Further studies are expected to improve the long-term antimicrobial effectiveness and sustainability of the natural limestone synthesized Ca(OH)₂ paste.

Abstract: Calcium hydroxide [Ca(OH)₂] has been widely used as an intracanal medicament especially in treatment of periapical lesion. This case report will discuss about calcium hydroxide as intracanal medicament in a periapical lesion of an upper left central incisor. This case describes about treatment of periapical lesion with suspect of infected cyst with symptoms and root resorption. Root canal preparation was done by crown down technique using protaper hands universal from S1/27mm until F5/27mm. Calcium hydroxide paste was continuously applicated every 2 weeks as intracanal medicament until the periapical index (PAI) of lesion decrease, in this case PAI decreased from scale 5 until scale 2 during three months recall. Calcium hydroxide supports tissue repair, stimulates fibroblast formation and damage the cytoplasmic membrane of bacteria, denature their proteins or damage the DNA by its alkaline property. As conclusion, the use of calcium hydroxide successfully decrease the periapical lesion index in the periapical radiograph examination and can be considered as a simple and effective medicament for endodontic infection.

Abstract: The objective of this paper is to introduce a patented and eco-friendly method to synthesize aqueous suspension of all types of alkaline-earth metal hydroxides nanoparticles (NPs). This method is based on an ion exchange process; the exchange takes place at ambient temperature/pressure, starts from cheap or renewable reagents and, in one single step, results in the creation of the crystalline desired nanoparticles in only a few minutes. In terms of structural and morphological features, the synthesized nanoparticles are characterized by means of XRD-Rietveld refinement, FTIR, and TEM. In particular, we obtained pure and crystalline magnesium and calcium hydroxide suspensions, showing the typical brucite crystal structure with a hexagonal lamellar morphology and dimensions generally <100 nm. With respect to the strontium and barium hydroxide suspensions, we observed different kinds of hydroxides (either anhydrous and hydrate forms), characterized by orthorhombic or monoclinic crystal lattices with rod-like nanostructured morphologies. Despite the different morphologies, all synthesized nanoparticles appear constituted by a superimposition of primary nanoparticles, of dimensions ranging from a few to 15 nm, correlated to the increase in the atomic number of the alkaline earth metal.

Abstract: Calcium hydroxide [Ca (OH)₂] has been the gold standard for endodontic medicament as inter-appointment dressing, due to its ability to act as antimicrobial agent and to promote hard tissue healing. The main mechanism of this material is the release of Ca²⁺ and OH^- ions through its vehicle, providing high alkaline pH. Indonesia, has many potential resources, namely limestone (CaCO₃), that can be utilized as raw material for Ca (OH)₂. The objective of this present study is to investigate the synthesis and characterization of Ca (OH)₂ from Indonesian limestone as endodontic intra-canal medicament. Limestone were taken from Palimanan area in West Java, Indonesia. CaCO₃ was calcined at 900°C for 4h resulting CaO powder. CaO powder were mixed with distilled water using a rotary stirrer for 24h and produce Ca (OH)₂ paste. The Ca (OH)₂ paste was dried at 80°C, then crushed using a mortar and pestle to obtain Ca (OH)₂ powder. The powder samples were thus subjected for characterization by X-Ray Diffraction (XRD) and Fourier-Transform Infrared (FTIR) Spectroscopy. The XRD patterns revealed that the high peak of Ca (OH)₂ crystallinity was successfully achieved in this study. The FTIR spectroscopy also showed bands at 3640 cm^-1 which belongs to OH^- stretching vibration of the Ca (OH)₂. The results indicate that the synthesize of Indonesian limestone as Ca (OH)₂ by this method was attained. Indonesian limestone is a potential raw material that can be used as a precursor for synthesis of Ca (OH)₂ as endodontic material.

Abstract: The mechanical strength of pulp capping material based on carbonate apatite and silica calcium-phosphate composite (CO₃Ap-SCPC) is one of the key factors for the success of the material in protecting the vitality of the pulp during the formation of apatite and dentin reparative. Modifying the material in the powder phase was known to increase the mechanical strength. The purpose of this study was to determine whether the addition of SCPC and calcium hydroxide in pulp capping materials based on CO₃Ap-SCPC would affect the compressive strength of this pulp capping material. In this study, three cement groups were used, each group consisted of dicalcium phosphate anhydrous and vaterite which added by SCPC concentration 0%, 5% and 10% and calcium hydroxide concentration 0%, 5% and 10%, respectively. All groups were tested by a compressive strength test and X-Ray diffraction (XRD) for phase analysis. The mean value of compressive strength with addition of 0% SCPC and 10% Ca(OH)₂ was 16.54 ± 1.35 MPa, addition of 5% SCPC and 5% Ca(OH)₂ of 18.55 ± 2.81 MPa, addition of 10% SCPC and 0% Ca(OH)₂ was 9.22 ± 1.21 MPa. The addition of SCPC and Ca(OH)₂ show statistically significant difference in compressive strength (p<0.05). The XRD analysis of the highest compressive strength revealed that the apatite crystal was successfully formed. It can be concluded that incorporated specific amount of SCPC and Ca(OH)₂ could improve the mechanical strength and the apatite formation of the CO₃Ap-SCPC pulp capping material.

Abstract: The stability of ettringite as high-watery mineral is highly dependent on the ambient temperature. Under standard laboratory conditions, onset of decomposition of this phase occurs at temperature of 80°C already and the theoretical temperature of the complete decomposition of ettringite is 180°C. Ettringite decomposition can occur at significantly different temperatures under humidity conditions other than the laboratory ones. Within the work verification of the possibility of synthetic preparation of ettringite by direct addition of aluminum sulfate, Al₂(SO₄)₃·18H₂O, and calcium hydroxide, Ca (OH)₂, as an alternative method to the yeelimite hydration procedure was carried out. The stability of the resulting systems was examined in two different environments, namely in a laboratory environment and the environment of saturated water vapour. The phase composition of the samples was determined by X-ray diffraction (XRD) analysis, thermal analysis and scanning electron microscopy (SEM).

Abstract: Calcium hydroxide (CH) is a by-product from hydration reaction of cement along with calcium silicate hydrate (C-S-H) gel. It helps to protect the steel reinforcements in concrete structures from corrosion process due to carbonation. The presence of calcium hydroxide provides a basic environment (pH˃10) that induces the formation of passive oxide film and keeps steel structures from corrosion. The detection and quantification of calcium hydroxide in concrete structures are important to understand the nature and state of the steel structures in concretes. In this research work, the variation of calcium hydroxide to calcium silicate ratios in cement were measured by using near-infrared spectroscopy (NIR). The first overtone of the OH groups in calcium hydroxide absorbs at 7082 cm^-1 and this absorption peak can be used as a quantitative measure of calcium hydroxide in samples. Correlation plot between second derivative absorbance intensity at 7082 cm^-1 with different mixtures of calcium hydroxide in calcium silicate base. The amount of calcium hydroxide in calcium silicate base was established. This calibration plot was used as basis for determining calcium hydroxide content in unknown concrete samples. Concrete samples for the quantitative determination of calcium hydroxide were prepared from standard cement samples and cement samples with or without pozzolan along with various water to cement ratios. The results show that all samples analyzed in this work contain calcium hydroxide in varying amounts. This variation reflects the composition of the cement and concrete samples.