Abstract: In order to improve the corrosion resistance, bioabsorbable magnesium (Mg) alloy was immersed in an aqueous solution with three times of Ca2+ and HPO42- in comparison with those of conventional SBF at the moderate temperature. After immersion in the solution, the whole surface of Mg alloy was coated with plate-like crystals consisting of octacalcium phosphate (OCP). Then the OCP-coated Mg alloy was immersed in the alkali solution. Although significant change of morphology was not observed, the OCP formed on the Mg alloy was transformed to hydroxyapatite (HAp) under alkali condition.
Abstract: Platelet Rich Fibrin (PRF) is a platelet that contains growth factor, such Vascular Endothelial Growth Factor (VEGF) that not only have implication in inflammation, stimulate tissue healing but also bone regeneration. The aim of this study was to evaluate the effect of combination PRF with bone graft (carbonate apatite) to VEGF level. This research is an experimental study, with consecutive sampling technique. This research was conducted by selecting 20 subjects (12 male, 8 female) which divided into two groups; 10 subjects in the treatment group were given bone graft and PRF application while another 10 subjects in the control group were given only bone graft without PRF application. The measurement of VEGF level was taken by inserting the paper point no.30 into sulcus before the surgery (D0) and one week after surgery (D7). VEGF level was assessed by ELISA method. All collected data were analyzed by using Wilcoxon test with p <0.05, and Mann-Whitney test with p <0.05. The treatment group, VEGF level at D0 was 3.8 pg/ml and D7 was 8,1 pg/ml. The difference in the level of VEGF was 4.3 pg/ml. The average of the control group at D0 was 4.5 pg/ml and D7 was 5.4 pg/ml, obtained the difference in the level of VEGF 0.9 pg/ml. The Mann Whitney Test analysis showed there was a significant difference between the treatment group and the control group with p-value 0.038. PRF with bone graft application influence the increased level of VEGF.
Abstract: Dental materials purely composed of calcium phosphate are ideal for the dental medicine. We have been developing ultrathin amorphous calcium phosphate (ACP) sheets for enamel repair. In this study, long term stability of the ultrathin ACP sheets applied on enamel surfaces which kept in a simulated intraoral condition for 21 days was evaluated. Surface morphologies of the ACP sheets were observed by optical images. A boundary condition between the ACP sheet and the enamel was evaluated by cross-sectional SEM image. A durability of the ACP sheet was evaluated by a brushing test conducted after 21 days incubation. As the result of these evaluations, it was confirmed that the ACP sheets were stable even after long-term incubation under the simulated intraoral environment condition.
Abstract: Porous β-tricalcium phosphate (β-TCP) foam granular cements was obtained by exposing different range size of β-TCP foam granular (300-600 μm and 600-1000 μm) with 1.4 mol/L of saturated acidic calcium phosphate solution at various setting reaction times. It was found that large amount of dicalcium phosphate dihydrate (DCPD) was formed in the set specimens after exposing small size of β-TCP foam granular with saturated acidic calcium phosphate solution. Morphological observation shows that the bridging of DCPD platelet-like crystals between β-TCP foam granular surfaces were detected as early as 10 mins after exposing 300-600 μm of β-TCP foam granules with saturated acidic calcium phosphate solution. In fact, the amount of DCPD formed in the specimens obtained from small size of β-TCP foam granules is higher than large sized foam granules. These results demonstrated that small size of β-TCP foam granules induced fast setting reaction of β-TCP foam granules to produce porous β-TCP foam granular cements.
Abstract: Carbonate apatite is one of the most widely studied bioceramic material for its use as bone cement. On the previous study, it has already stated that CO3Ap cement has good osteoconductivity which makes this cement could be replaced by bone. However, the mechanical strength of CO3Ap cement is still low. This low mechanical strength is estimated due to the high porosity and absence of organic components. The aim of this study is to improve the mechanical strength of the CO3Ap cement reinforced by gelatin as an organic component with genipin as a cross-linking agent (Gelapin). The powder phase of vaterite and DCPA at weight ratio 40:60 were mixed with 0.2 mol/L Na2HPO4, 5% (w/v) gelatin, and 20% (v/v) genipin using 0.5 liquid to powder (L/P) ratio. The liquid phase ratios of Na2HPO4 and Gelapin were 50:50, 70:30, and 90:10. For control group, Gelapin were didn’t mixed in the liquid. Diametral tensile strength was improving and statistically significant (p<0.05) on set cement with 50:50 liquid ratio, the average value was 6.02 ± 0.14 MPa whereas the average value of the control group was only 3.10 ± 0.15 MPa. For this instance, gelatin serves a polymer matrix so the carbonate apatite crystallites could be well distributed within it which then gives more flexibility and resistance for the cement. On the other hand, genipin was also successfully cross-linked the gelatin. This study showed that by reinforcing CO3Ap cement using genipin cross-linked gelatin might be a good candidate for a bone substitute material.
Abstract: Pulp capping has been suggested as one treatment of choice after pulp exposure. Calcium hydroxide [Ca (OH)2] recognized as gold standard of direct pulp capping matter for some decades. Throughout the time, a new cement known as mineral trioxide aggregate (MTA) has developed into a prominent alternative. A recent study found that matter as the most effective pulp capping material. Despite the fact, MTA is an expensive material. Several studies in different country show that portland cement has highly similarity chemical composition with MTA. The purpose of this study is to evaluate the chemical composition of white portland cement that fabricated in Indonesia compared to MTA. White portland cement fabricated in Indonesia was used as a sample in this study and commercial MTA as a control. Samples and control were assessed using X-ray fluorescence spectrometry (XRF) to figure out chemical composition and concentration. Investigating the wavelength of the functional group using Fourier Transform Infrared Spectroscopy (FTIR). The results show that composition, concentration, and functional group either Indonesian white portland cement and MTA has highly similar. Hence, it has a chance to use Indonesian white portland cement for dental pulp capping material as MTA substitution.
Abstract: Apatite cement is ideal self-setting cement for bone substitute material, however its use is limited only to areas that receive minimum load bearing because mechanical strength of apatite cement is low. Silica-calcium phosphate nanocomposite (SCPC50) is material having good mechanical strength and has an important role in bone remodeling (bone metabolism), mineralization, synthesis of cartilage, collagen production, proliferation and differentiation of bone cells. However, the unsetting and granule’s physical shape of SCPC50 limits the application. The purpose of this study is to determine the effect of various mixtures of SCPC50 and apatite cement to manipulative index (setting time and handling property), and mechanical properties. The experimental results show that the setting time of apatite cement mixture with 5% and 10% SCPC50 was 40% higher (p<0.05). The mechanical strength evaluated by Diametral Tensile Strength showed that the addition of both 5% silica and 10% SCPC50 composition to apatite cement mixture increased the mechanical strength of apatite cement mixture (p<0.1). The handling property of cement paste was significantly increased between the apatite cement without SCPC50 and apatite cement with both 5% SCPC50 and 10% SCPC50 (p<0.05). It is concluded that the addition of SCPC50 to apatite cement mixture could improve the mechanical properties and it is expected to improve its bioactivity.
Abstract: Sintering of zirconia usually takes a long time. In recent years, new products with extremely short sintering time have been released. Therefore, it is useful to study in detail the effect of sintering temperature and time on translucency of zirconia. The prepared discs were sintered under four conditions; 30 minutes, 40 minutes, 50 minutes and 60 minutes as firing temperature rising time up to 1500°C. Samples were measured with a spectrophotometer and translucency parameter (TP), opalescence parameter (OP) and contrast ratio (CR) were calculated. In this study, there were no statistically significant differences between TP, OP and CR due to the differences in heating rates. There is a possibility that a heating time up to the sintering temperature does not affect translucency of zirconia.
Abstract: Various bioceramic materials including zirconia and hydroxyapatite have been developed for various applications. Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) is one of the most interesting features of calcium phosphate-based bioceramic that widely used in various applications especially for bio-application, bone engineering, and dentistry. However, the applications of pristine HAp have limited due to low load bearing applications. The wet chemical precipitation techniques was used to synthesize the solids based on zirconia. Hydroxyapatite and zirconia powder (0-30 weight %) were mixed homogeneously. Structure and morphological were characterized by SEM JEOL-JSM-T330A. The presence of functional group was observed by FTIR. Hardness value of material was measured by using Vickers hardness test measurement. Through this techniques, pure hydroxyapatite precipitate was obtained. Sintering temperature is an important factor that could influence the hardness of zirconia-doped hydroxyapatite. Based on the SEM observation, zirconia-doped hydroxyapatite were developed in blended morphology. FTIR results shows the interaction between hydroxyapatite and zirconia. Increasing zirconia increased the hardness value of zirconia-doped hydroxyapatite. Eventually, these ceramic-based materials could be developed for dental materials applications.