Polyvinylpyrrolidone—Alginate—Carbonate Hydroxyapatite Porous Composites for Dental Applications

Abstract

An alternative approach for the currently used replacement therapy in dentistry is to apply materials that restore tooth tissue. Among them, composites, based on biopolymers with calcium phosphates, and cells can be applied. In the present work, a composite based on polyvinylpyrrolidone (PVP) and alginate (Alg) with carbonate hydroxyapatite (CHA) was prepared and characterized. The composite was investigated by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance (EPR) and scanning electron microscopy methods, and the microstructure, porosity, and swelling properties of the material were described. In vitro studies included the MTT test using mouse fibroblasts, and adhesion and survivability tests with human dental pulp stem cells (DPSC). The mineral component of the composite corresponded to CHA with an admixture of amorphous calcium phosphate. The presence of a bond between the polymer matrix and CHA particles was shown by EPR. The structure of the material was represented by micro- (30–190 μm) and nano-pores (average 8.71 ± 4.15 nm). The swelling measurements attested that CHA addition increased the polymer matrix hydrophilicity by 200%. In vitro studies demonstrated the biocompatibility of PVP-Alg-CHA (95 ± 5% cell viability), and DPSC located inside the pores. It was concluded that the PVP-Alg-CHA porous composite is promising for dentistry applications.

Comparison between Two Different Synthesis Methods of Strontium-Doped Hydroxyapatite Designed for Osteoporotic Bone Restoration

“…The signals at 561 and 600 cm −1 as well as the signals from 962, 1024, and 1091 cm −1 are assigned to the PO 4 3− asymmetric bending and asymmetric stretching vibration groups [29]. The stretching vibration of the CO 3 2− from HA samples is observed at 1421 cm −1 , specific to the substitution of B-type HA with a low unit cell volume [30], and the signal at 874 cm −1 can indicate the presence of the CO 3 2− ions, which might occur during the synthesis [31]. The absence of the 1550 cm −1 vibration points out the low replacement of OH − groups by CO 3 2− in the channels of the HA structure and thus, the absence of A-type HA [30].…”

“…presence of the CO3 2− ions, which might occur during the synthesis [31]. The absence of the 1550 cm −1 vibration points out the low replacement of OHgroups by CO3 2− in the channels of the HA structure and thus, the absence of A-type HA [30]. The signal at 1636 cm −1 could be assigned to the in-plane H-O-H bending mode of the absorbed water.…”

“…The stretching vibration of the CO 3 2− from HA samples is observed at 1421 cm −1 , specific to the substitution of B-type HA with a low unit cell volume [30], and the signal at 874 cm −1 can indicate the presence of the CO 3 2− ions, which might occur during the synthesis [31]. The absence of the 1550 cm −1 vibration points out the low replacement of OH − groups by CO 3 2− in the channels of the HA structure and thus, the absence of A-type HA [30]. The signal at 1636 cm −1 could be assigned to the in-plane H-O-H bending mode of the absorbed water.…”

Microwaved-Assisted Synthesis of Starch-Based Biopolymer Membranes for Novel Green Electrochemical Energy Storage Devices

“…There is prevalent global pollution with plastics at the macro-and microscales; therefore, it is necessary to limit this kind of pollution in the environment. This is why, in recent years, so many studies have proposed that the use of biopolymers can compete with traditional plastic polymers in many crucial fields such as medicine [1][2][3], the food industry [4,5], safety [6], and energy storage [7][8][9].…”

“…Starch, a naturally occurring carbohydrate that is abundant in various plant sources, finds extensive applications in different industries, which showcases its versatility and utility [55]. It is a natural polymer produced from amylose and amylopectin, two types of polysaccharides built of α-d-glucopyranosyl units connected by (1,4) and (1,6) bonds [56] (Figure 1). Due to its cellulosic features, starch is considered a promising low-environmental-impact material and is widely applied in the food, paper, and textile industries and many more [57][58][59][60][61].…”