Dental materials journal最新文献

We aimed to improve the biocompatibility and osteoinductive potential of Ti implants using a simulated intraoral hydroxyapatite (HAp) coating. We devised a novel surface treatment for aggressive induction of osteoblast adhesion and bone regeneration on the implant surface. A thin α-tricalcium phosphate (α-TCP) film was deposited on the implant surface using a pulsed Er:YAG laser. The coating was converted to HAp through artificial saliva immersion, which was confirmed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM showed needle-like HAp crystals on the Ti disks and sandblasted implant surfaces after immersion in artificial saliva for 96 h. Microcomputed tomography and histological evaluation 4 and 8 weeks after implantation into beagle dog mandibles showed that the HAp-coated implant was biocompatible and exhibited superior osteoinduction compared to that of sandblasted implants. Coating the implant surface with HAp using an Er:YAG laser has potential as a new method of the implant-surface debridement.

Surface pre-reacted glass-ionomer (S-PRG) filler is a bioactive glass filler capable of releasing various ions. A culture medium to which was added an S-PRG filler eluate rich in boron was reported to enhance alkaline phosphatase (ALP) activity in human dental pulp-derived stem cells (hDPSC). To clarify the role of boron eluted from S-PRG fillers, the modified S-PRG filler eluate with different boron concentrations was prepared by using an anion exchange material. Therefore, elemental mapping analysis of anion exchange material, adsorption ratio, hDPSCs proliferation and ALP activity were evaluated. For statistical analysis, Kruskal-Wallis test was used, with statistical significance determined at p<0.05. ALP activity enhancement was not observed in hDPSC cultured in the medium that contained the S-PRG filler eluate from which boron had been removed. The result suggested the possibility that an S-PRG filler eluate with controlled boron release could be useful for the development of novel dental materials.

This study evaluated the bonding performance of coronal dentin disks, designed for biological restoration, and CAD/CAM resin composite disks when bonded to flat dentin surfaces using dual-cure resin cements, with and without a resin-coating (RC) technique. Three distinct groups were established within the non-RC group, each using one of the two types of resin cements in a self-adhesive mode: one-step self-etch adhesive (1-SEA) without light-cure, 1-SEA with light-cure, and a separate group using an alternate cement. Within the RC group, a subgroup was established for each cement. The microtensile bond strength (μTBS) of the disk-dentin beam was tested after 0 and 10,000 thermocycles in a 5°C/55°C. No significant μTBS difference was observed among the non-RC groups. However, when using RC, the μTBSs of coronal dentin disks significantly exceeded those of CAD/CAM resin composite disks. Thermocycle aging did not affect μTBS in any of the bonding methods, except in self-adhesive mode.

This study investigated the effects of low-temperature degradation (LTD) on the L*, a*, and b* values of highly translucent zirconia crowns. Four types of zirconia disks with different yttria contents (IPS e.max ZirCAD LT, IPS e.max ZirCAD MT, IPS e.max ZirCAD MT Multi, IPS e.max ZirCAD Prime, Ivoclar) and two shades (A2 and BL) were used. A crown was manufactured using four types of zirconia and LTD treated. Color measurements were performed, and the color difference (ΔE₀₀) before and after LTD was calculated. The microstructure was determined through X-ray fluorescence and X-ray diffractometry. Highly translucent zirconia crowns showed greater changes in the a* and b* values than in the L* value after LTD, regardless of the shade. The Multi2 crowns exhibited a discernible color change due to the LTD treatment. The X-ray fluorescence results did not reveal any apparent change in the microstructure between sintering programs for all zirconia specimens.

This study aimed to evaluate the wear resistance of primary tooth enamel and 3 kinds of 3D printing materials and to compare the marginal fitness and internal suitability of prefabricated all-ceramic crowns, computer-aided design/manufacturing (CAD/CAM) all-ceramic crowns, and three 3D-printed deciduous molar crowns. Multifunctional friction wear testing machine was used to image the wear surface of the sample and calculate the maximum wear depth and volume loss value of each sample. The internal fit evaluation used the silicon replica method, The four points were measured using scanning electron microscopy (SEM). The obtained data were statistically analyzed using ANOVA and Tukey HSD-test with a fully randomized design (p<0.05). The results showed the wear resistance of E-Dent400 was better than that of PEEK and three different 3D printed materials have good wear resistance compared with the primary tooth enamel. The measured values at M1 and M4 of E-Dent400 were both the smallest.

To design biologically active, collagen-based scaffolds for bone tissue engineering, we have synthesized chimeric proteins consisting of stromal cell-derived factor-1α (SDF) and the von Willebrand factor A3 collagen-binding domain (CBD). The chimeric proteins were used to evaluate the effect of domain linkage and its order on the structure and function of the SDF and CBD. The structure of the chimeric proteins was analyzed by circular dichroism spectroscopy, while functional analysis was performed by a cell migration assay for the SDF domain and a collagen-binding assay for the CBD domain. Furthermore, computational structural prediction was conducted for the chimeric proteins to examine the consistency with the results of structural and functional analyses. Our structural and functional analyses as well as structural prediction revealed that linking two domains can affect their functions. However, their order had minor effects on the three-dimensional structure of CBD and SDF in the chimeric proteins.

In this study, we investigated the effects of surface treatment on the fracture strength of porcelain-veneered zirconia. Highly translucent 4 mol% yttria-stabilized zirconia disks (KATANA HT, Kuraray Noritake Dental) were divided into three surface-treatment groups: 1)as-sintered, 2) alumina sandblasted, and 3) ground. Crystallographic and surface-roughness analyses were conducted for each group. Veneering ceramics (Cerabien ZR, Kuraray Noritake Dental) were applied to the zirconia surfaces. The fracture strengths of the porcelain-veneered zirconia disks were measured using biaxial flexural-strength tests. Crystallographic analysis revealed that grinding and sandblasting increased the fractions of the monoclinic and rhombohedral zirconia phases. The ground specimens had a higher surface roughness than the sandblasted specimens. Weibull analysis showed no significant differences in biaxial flexural strength among the three groups. The results suggest that these surface treatments do not affect the fracture strength of porcelain-veneered zirconia.

This systematic review investigates the effectiveness of calcium and phosphate ions release on the bioactivity and remineralization potential of glass ionomer cement (GIC). Electronic databases, including PubMed-MEDLINE, Scopus, and Web of Science, were systematically searched according to PRISMA guidelines. This review was registered in the PROSPERO database. Five eligible studies on modifying GIC with calcium and phosphate ions were included. The risk of bias was assessed using the RoBDEMAT tool. The incorporation of these ions into GIC enhanced its bioactivity and remineralization properties. It promoted hydroxyapatite formation, which is crucial for remineralization, increased pH and inhibited cariogenic bacteria growth. This finding has implications for the development of more effective dental materials. This can contribute to improved oral health outcomes and the management of dental caries, addressing a prevalent and costly oral health issue. Nevertheless, comprehensive longitudinal investigations are needed to evaluate the clinical efficacy of this GIC's modification.

Cellulose nanofibrils (CNFs) exhibit excellent mechanical properties and are used to reinforce various composites. The effects of incorporating CNFs into commercial mineral trioxide aggregate (MTA) cements (NEX MTA (NEX) and ProRoot^® MTA (PR)) on the underwater setting properties, compressive strength, and flowability were estimated in this study. NEX mixed without CNFs disintegrated after water immersion. NEX mixed with CNF-suspended solutions showed good setting properties under water immersion and a similar compressive strength, which was kept in air (100% relative humidity). PR did not degrade after water immersion, regardless of the presence of CNFs, and no significant difference in the compressive strength caused by CNFs incorporation was detected. The relative flowability of the NEX mixture decreased with increasing CNFs content up to 1.0 w/v%. The application of CNF-incorporated MTA in various dental cases is promising because CNFs prevent the water-immersion-dependent collapse of some MTA cements immediately after mixing.

The objective of the study was to evaluate the effects of dentin deproteinization protocols for post space using different formulations containing sodium hypochlorite before fiber post cementation with self-adhesive resinous cement. The groups were divided according to the irrigation protocol (DWC, SHS, SHT and SHG). The residue cleanliness, bond strength, adhesive failure pattern, and tag formation at the adhesive interface between the self-adhesive cement and the dentin were evaluated. For this, analysis in scanning electron microscope, push-out test and confocal laser scanning microscopy were performed. The SHT protocol showed the highest residue cleanliness on the dentin surface of the post space (p<0.05). In addition, SHT protocol showed highest bond strength and tag formation in the cervical and middle thirds (p<0.05). Dentin deproteinization with sodium hypochlorite with surfactant provided the best dentin cleaning of residues, bond strength and tag formation after cementation of the fiber post with self-adhesive cement.