The present work aims to carry out modal analysis of a functionally graded material (FGM) plate to determine its natural frequencies and mode shapes by using Finite Element Method (FEM). For this purpose, a code was written in MATLAB and linked with ABAQUS. First, a simulation was performed in accordance to other researcher’s model, and then after comparing the obtained results, the accuracy of the present study was verified. The obtained results for natural frequency and mode shapes indicate good performance of user-written subroutine as well as FEM model used in present study. After verification of obtained results, the effect of clamping condition and the material type (i.e., the parameter n) was investigated. In this respect, finite element analysis was carried out in fully clamped condition for different values of n. The results indicate that the natural frequency decreases with increase of n, since with increase of n, the amount of ceramic phase in FGM plate decreases, while the amount of metal phase increases, leading to decrease of the plate stiffness and hence, natural frequency, as the Young modulus of Al2O3 is equal to 380 GPa and the Young modulus of SUS304 is equal to 207 GPa.

The treatment of complicated crown-root fractures of tooth is often compromised by a fracture apical to the gingival margin and/or bone. This makes isolation difficult and compromises the adhesive union which is critical for a successful treatment. In the present case, the fracture line extended from cervical third of labial surface to cervical third of palatal surface sub gingivally which made the case a complicated crown root fracture. The reattachment of fragments would bring the vulnerable joint in the primary stress bearing area and in the subgingival region. Hence the tooth was removed traumatically with the help of periotome and intentional replantation was done which facilitated the attachment of fragments extra orally. Fragments reattachment was reinforced with the intraradicular fiber post and glass ionomer cement. Then the tooth was rotated 1800 to bring the subgingival fracture line to the labial surface where the occlusal load is less. As the amount of extra oral time is a critical factor in the success of reimplantation, the procedure was completed in 20 minutes. The teeth were stabilized with semi rigid splint for 6 weeks. Later full veneer crown was cemented on the tooth. The patient was followed up with clinical examination for mobility test, gingival sulcus depth and radiographic analysis to analyze the integrity of root, the alveolar cortex and the periodontal space for 12 months. The treatment is successful so far and has rendered satisfaction to both the clinician and patient.

This work aims to synthesize chitosan from locally available cowry and crab shells for Pharmaceutical application in drug delivery. Chitosan was synthesized from both shells using standard deacetylation technique. The synthesized chitosan, piroxicam and lactose were employed in preparing the drug loaded tablets by direct compression technique and subjected to characterization with the aid of Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Spectroscopy (SEM) and optical microscopy. Finally, the drug release rate was investigated with in vitro drug dissolution test. The results of FTIR spectra confirmed that the biopolymer extract was chitosan and it also shows that there was no interaction between chitosan and the piroxicam. The morphological properties of the samples were found to be suitable for drug delivery. The applied load and composition of tablets influenced the drug release rates.

As a third-generation biomaterial, the bioactive glass (BG) has gained the attention of various research groups who have started to employ it for enhancing tissue regeneration. Most of these applications focus on bone tissue engineering based on either BG alone or BG-based composites, where the properties of the other components can improve those of the BG. Moreover, recently, the BG has become one of the important materials with ability to improve the regeneration of soft tissues. This review highlights the up-to-date advances in the different BG-based composites which have been studied in the treatment of various soft tissue injuries. These include the neuronal, muscle, lung and cardiac tissue regeneration, as well as cornea treatment. In addition, the enhancement in tissue repair due to the composite structure is discussed with comparing to the individual component structures.

Hip fracture in frail people is an increasing problem with a major socio-economic impact. Besides, a first hip fracture is often followed by a second fracture of the opposite hip in the following years. The authors report on four cases with extra-capsular hip fractures treated not, only for the fracture but also to avoid future contralateral fracture by implanting an innovative device as a preventive measurement.

In the present study composites based on polylactide and hydroxyapatite with the content of components 50:50 and 75:25 were investigated. Components were mixed at 40°C, which was followed by the sonication procedures and its precipitation in ethanol. The analysis of the following composite materials revealed that their chemicalcrystallographic characteristics of individual components remained intact after varying its dispersion and material crystallinity degree. Composite material of the ratio 75:25 were characterized by the lowest degree of crystallinity - 20.5% and the average crystallite size up to 28.8 nm showed an increased roughness and dispersive component of surface energy. In comparison to polylactide, the composite has a high capacity for osseointegration. In the paper, special attention is given to the immunomodulatory properties of composite materials. Assessment of the immune system cells showed that the macrophages are most viable in the presence of pure polylactide and composite 75/25. Intensive secretion of proinflammatory cytokines in macrophage cultures in vitro was not found at that.

Successful application of 1:1 layered phyllosilicates as excipients of drugs and agrochemicals depends on the efficiency and effectiveness of activation reactions carried out prior to their usage. Reluctance of kaolinite to direct reactions involving interlayer spaces created a challenge which requires a sustainable search for optimum activation agents. This study investigated the features of cyclone based wet beneficiated kaolinite with kaolinite sheets activated using solid dispersion of NaCl. Starting materials and the resulting activated counterparts were characterized for their chemistry, functionalities (as per mineral phases present), and variation of crystal sizes upon each treatment cycle along with lattice contraction and expansion in the interlayer spaces and orientation of layers (as per their morphological changes) as well as molecular vibration. It was observed that, upon successful activation with NaCl, there was a significant change in the orientation of kaolinite sheets from euhedral pseudohexagonal platelets into vermiform whose pattern offer a maximum orientation for reactions involving interlayer spaces. The formation of vermiform which may be due to packing of nano-layers was noted to be associated with the contraction of interlayer spaces of about 0.018 nm from 2θ = 12.543o to 12.552o as revealed in the x-ray diffraction trials. Therefore, the ability of NaCl activation reactions to orient kaolinite layers into well-ordered vermiform pattern makes NaCl a suitable activation agent for use when kaolinite is to be used for design of excipients for drugs and agrochemicals.

Binder-jet 3D printing responses of sea-shell powder based ceramic composites have been evaluated considering the material consolidation mechanisms and mechanical characterisations. Initial experimental printing trials are done manually, varying the composition of the composite powders from 5% to 50% of the seashell powder and the rest plaster. Overall, the seashell and plaster combinations worked well in terms of achieving the necessary green strengths within the binder-jet process conditions. Scanning electron microscopy and 3-point bending results indicated no significant loss of properties at lower levels of the seashell component, but the strength decreased beyond the 25% mark. The optimum levels of seashell powder are found to be within 15-20% by weight in terms of the best compression strengths. Neat sea-shell powder however goes too sticky immediately after the interaction with the binder liquid and does not show evidence of any binding mechanism that can be accelerated.

Some phosphate glasses containing different amounts of by-pass cement dust (BCD) were prepared by the melt quenching method. The selected molecular composition was [(100-x)% - P2O5 (x)% BCD (where 30≤ x≥60)]. The obtained experimental density and molar volume values were inspected and were then compared with those obtained empirically for the close packed structure of the corresponding compounds. The comparison between experimental and emperical values evidenced the short range order of the studied samples. The electric and dielectric properties were thoroughly investigated. The appearance of maxima and minima in the total conductivity BCD concentration dependence can be attributed to the mixed alkali – alkaline earth effect (MAAE) and to the presence of considerable amount of CaO. The suitability of such glasses to act as gamma-ray shielding materials was thoroughly investigated, and correlation between the chemical composition (the BCD concentration) and gamma-ray attenuation behavior was established.

The antimicrobial effect of staphylococcus aureus, Streptococcus mutans, E. coli and Candida albicans are dependent on surface properties and restorative dental materials types. The aim of this study was to evaluate the effect of antibiotics on the residual natural saliva (after Filtek, glass-ionomer, porcelain and zirconia takeout from it). Also, the effect of brushing on fungi and bacteria growth in these surface materials was characterized. The results show that, bacterial growth around Filtek, glass ionomer, porcelain, and zirconia materials after takeout from saliva that is meant these materials have no resistance for E. coli, staphylococcus aureus, Streptococcus mutans and Candida albicans. The color of residual saliva changed. All antibiotics caused inhabitation zone except Ampicillin. Ciprofloxacin shows significant inhibition zone for all used materials. Also, brushing removed most if not all fungi and bacteria formed on surface dental materials.