European Journal of Dentistry最新文献

Over the past decade, the occurrence of bone defects has seen a notable rise. In both developed and developing nations, their prevalence tends to increase in parallel with population density and levels of physical activity. Various therapeutic approaches have been implemented to address bone fractures, focusing on preventing infections, promoting faster healing, and restoring normal bone function. Among these, bone grafting-a surgical technique involving the use of biomaterials-remains a widely utilized method for bone replacement. This review aims to identify biomaterials that have biocompatibility with bone, osteoinductive, and osteoconductive properties so that they can trigger good osteogenesis. This review is based on a compilation of publications from various databases related to factors affecting the process of bone ossification. This study also evaluates the characteristics of hydroxyapatite biomaterials that play a role in inducing osteogenesis. The phosphate/calcium ratio close to 1.67, porosity in the range of 40 to 60%, pore diameter of 200 to 900 nm, and crystallinity of 40 to 60% will help the osteogenesis to perform well. The results of this study highlight the advantages of hydroxyapatite in terms of its osteoconductive, osteoinductive, and osteointegrative properties, which can trigger osteogenesis.

This study aimed to evaluate the impact of different surface pretreatments and bonding protocols on the shear bond strength (SBS) of two monolithic zirconia materials to composite resin.A total of 200 zirconia specimens, 3Y-TZP (n = 100) and 5YSZ (n = 100), were allocated into five groups: Control with no treatment, air-particle abrasion (APA), Nd:YAG (neodymium-doped yttrium aluminum garnet) laser treatment (L), a combination of APA and L, and laser treatment followed by cold plasma (CAP). Half of the specimens received a primer application before bonding with resin cement. Surface morphology was assessed using scanning electron microscopy, and SBS testing was conducted with a universal testing machine.The SBS analysis was done using multiway analysis of variance (p ≤ 0.05).Different surface pretreatments and 10-methacryloyloxydecyl dihydrogen phosphate primer application significantly increased SBS values (p ≤ 0.001). APA was associated with the highest SBS values, followed by APA + laser and laser + CAP. However, the combination of APA with L slightly reduce the bond strength. While the application of laser alone possesses the lowest SBS among the surface pretreatment methods, the control group was the worst by far. Different zirconia materials showed no impact on SBS values.APA surface pretreatment might still be the gold standard for zirconia adhesion. Laser surface pretreatment is a viable, less destructive option. Combining APA with laser slightly reduces SBS, while combining two inert surface pretreatment methods, such as laser and CAP, leads to enhancement of SBS compared with laser alone. Zirconia primer is highly recommended for bonding protocol. No special considerations should be taken for different yttria contents, as both materials reported comparable bond strength within the same coupled variables.

The objective of this study was to evaluate the bonding performance and the interfacial ultramorphology of an innovative self-curing restorative system compared with a conventional light-curing resin composite applied on dentin in etch-and-rinse (ER) or self-etch (SE) mode.Twenty cavities (class I) were prepared in sound dentin and restored using two materials: (1) CERAM (n = 10; CERAM.X ONE, Dentsply Sirona) in combination with a universal adhesive system (PBU [Prime & Bond Universal]), or (2) STELA (n = 10; Stela Automix, SDI) in combination with its adhesive primer. Half of the specimens from each group were bonded in ER or SE mode. Specimens underwent microtensile bond strength testing after 24 hours of storage in artificial saliva. Failure mode was determined using a stereomicroscope, and fractographic analysis was performed using scanning electron microscopy. The interfacial ultramorphology/nanoleakage of the resin-dentin slabs was analyzed through dye-assisted confocal microscopy.For quantitative analysis, bond strength values (in MPa) were assessed for normality and variance using Kolmogorov-Smirnov and Levene's tests, followed by ANOVA based on restorative material and adhesive bonding protocol, with Fisher's least significant difference post hoc test (α = 5%).SE groups exhibited significantly lower bond strength (17.4 MPa for CERAM; 26.2 MPa for STELA) compared with ER groups (35.8 MPa for CERAM; 33.6 MPa for STELA) (p < 0.05). CERAM applied in SE mode showed significantly lower bond strength compared with STELA applied in SE mode. Furthermore, CERAM applied in SE mode was the only group presenting a pre-test failure rate (27%). The failure mode was predominantly mixed in ER groups and adhesive in SE groups. Nanoleakage was observed clearly in the CERAM groups applied in both ER and SE modes but was less evident in the STELA groups.The new self-curing material (STELA) used in SE or ER may represent a promising clinical option to provide adequate interfacial adaptation and strong bonding to dentin when restoring deep class I cavities. The use of conventional adhesives in deep class I cavities may generate resin-dentin interfaces characterized by gaps and leakages.

For cementation of ceramic restorations, a layer of adhesive followed by resin cement is applied to the treated enamel surface. The light activation of adhesive may occur before or simultaneously with the resin cement. The aim of this study was to evaluate the influence of ceramic thickness and previous light activation of adhesive on shear strength of resin cement to enamel.Vestibular bovine enamel was bonded to lithium disilicate ceramic cylinders with resin cement. The samples were divided into two groups, according to the ceramic thickness (1 or 2 mm). The cylinders had one surface treated for cementation and the enamel surface was treated with acid etching and adhesive system. Only half of samples received light activation of the adhesive prior to cementation. The samples were stored for 30 days in water at 37°C, and then subjected to the shear bond strength test.Two-way analysis of variance was applied to evaluate the influence of previous light activation and ceramic thickness on the bond strength to enamel (α = 0.05).The results of this study indicated that there is no significant difference in the shear adhesive strength between ceramics and dental enamel in relation to the factors evaluated.It is concluded that bond strength is not affected by neither the previous adhesive light activation nor ceramic thickness (1 or 2 mm).

This study aims to compare the elemental composition and surface characteristics of root cementum in teeth affected by severe periodontitis with those of healthy teeth.Forty-seven teeth, including 25 teeth affected by stage III, grade C periodontitis and 22 healthy teeth, were extracted from patients aged 17 to 34 years. The cementum surfaces were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) to evaluate surface morphology and elemental composition.SEM images revealed that healthy teeth exhibited a homogenous, smooth cementum surface, while teeth affected by periodontitis showed an irregular, uneven surface with deep crack lines and resorption areas. EDX analysis indicated significant differences in elemental composition; periodontitis-affected teeth had lower calcium and phosphorus but higher magnesium, sodium, and sulfur levels than healthy teeth.Periodontitis significantly alters the surface characteristics and elemental composition of root cementum, which may contribute to disease progression and impaired periodontal health.

Beta-tricalcium phosphate (β-TCP) is a synthetic graft material with excellent biocompatibility, osteoconductivity, and osteoinductivity. β-TCP may induce adipose-derived mesenchymal stem cells (ADMSCs) osteodifferentiation. This study aims to investigate the osteoinductivity of 300 to 600 and 600 to 1,000μm β-TCP in ADMSCs.ADMSCs were obtained from the visceral adipose tissue of young male rabbits. To determine the osteoinductive ability, bone morphogenic protein 2 (BMP-2), Osterix, runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteopontin, and osteonectin expression was examined using an immunochemical assay on ADMSCs conditioned with an osteogenic medium and a β-TCP bioceramic with granule sizes of 300 to 600 and 600 to 1,000 µm (100 ng diluted to 100 nmol as the final concentration). A 3,3'-diaminobenzidine staining kit was used for immunocytochemical staining. Anti-BMP-2, anti-Osterix, anti-Runx2, anti-ALP, anti-osteopontin, and anti-osteonectin monoclonal antibodies were employed at a 1:500 dilution. A light microscope with magnifications of 400× and 1,000× was used to manually observe and examine cultures in five different fields of view.BMP 2, Runx2, Osterix, and ALP expression was higher in ADMSCs + β-TCP 300 to 600 µm compared with the control group (p < 0.05). Osteonectin and osteopontin expression was higher in ADMSCs + 300 to 600 µm β-TCP compared with the control group (p < 0.05) and ADMSCs + 600 to 1,000 µm β-TCP (p < 0.05).ADMSC osteodifferentiation was influenced by β-TCP bioceramic granule size. The considerable difference in osteonectin and osteopontin expression supports the idea that 300 to 600 µm β-TCP induce ADMSCs osteodifferentiation than 600 to 1,000 µm β-TCP.

This study aimed to evaluate whether adopting a horizontal viewpoint, facilitated by a novel digital assistive device, could enhance endodontic file placement accuracy and reduce operator-dependent variability during root canal treatment.A total of 40 modified upper jaw dental stone models, each accommodating a plastic tooth replacing the upper right second molar, were divided into two groups (n = 20 each). The mesiobuccal canal of each tooth was prepared to a standardized working length of 21.0 mm and a working width of size 35. A size 40 file with a stopper preadjusted to 19.0 mm was then inserted. In the first (conventional) group, files were placed without assistance; in the second (device-assisted) group, a horizontal-view digital device was designed, developed, and used to align and insert the file. The second operator, blinded to the device's purpose, performed all insertions under simulated clinical conditions. An intraoral scanner subsequently captured the vertical distance from the stopper's bottom surface to a standardized anatomical landmark. Pairwise comparisons between the two groups were computed using alignment software to account for potential measurement artifacts.Normality in both groups was confirmed via the Shapiro-Wilk test. An independent-samples t-test compared mean vertical distances. Additionally, differences in stopper positioning were calculated for all aligned virtual models in CloudCompare.The device-assisted group exhibited a significantly shorter mean stopper-to-landmark distance (0.425 mm, standard deviation [SD] = 0.225) than the conventional group (0.971 mm, SD = 0.432) (t = -5.014, p = 2.534 × 10^-5). Pairwise analysis highlighted closer apical positioning in the device-assisted group, closely matching pilot study findings that a 26.57° vertical viewing angle can distort perceptions by 0.5 mm. The device's mean intraoral mounting time was 224 s (SD = 35.2), considered negligible over the full treatment duration.Adopting a horizontal perspective with a novel digital assistive device significantly improved file placement accuracy and reduced operator-dependent variability during root canal treatment. Optimizing this device's design and assessing its cost-effectiveness may facilitate broader clinical adoption and further enhance endodontic procedural outcomes.

Certain factors that disturb the tumor microenvironment influence the promotion of tumorigenesis. Detecting gene expression at the protein level is highly valuable and complements the histopathological analysis achieved by immunohistochemistry (IHC). Hypoxia-inducible factor (HIF)-1α accomplishes autophagy induction and regulation of autophagy-associated genes. So, this study was carried out to evaluate the tissue protein expression of Beclin-1 and HIF-1α using IHC and correlate their expression with the prognosis of oral squamous cell carcinoma (OSCC).Immunohistochemical evaluation of Beclin-1 and HIF-1α was done in 5 samples of normal oral epithelial tissues and 45 samples of OSCC, which were classified histologically into 15 samples each of well, moderately, and poorly differentiated squamous cell carcinoma.According to statistics, normal tissue had the highest values for Beclin-1, while poorly differentiated OSCC had the lowest mean area percentage. HIF-1α showed the opposite results. These results indicate that the association of both molecules has a greater role in the transformation from normal to different histopathological grades of OSCC.The close association between Beclin-1 and HIF-1α identified in the current study confirms hypoxia's critical role in autophagy activation. Moreover, reduced Beclin-1 and elevated HIF-1α expression were significantly associated with the histopathological grading of OSCC, supporting their pivotal role in the development and progression of OSCC.

The release of growth factors in injectable platelet-rich fibrin (I-PRF) exhibits a peak within 24 hours and subsequent decline by day 10, underscoring immediate application, limiting its effectiveness in alveolar bone repair. In order to enhance its regenerative potential, I-PRF can be combined with biomaterial scaffolds such as collagen-chitosan hydrogels, which mimic the extracellular matrix and support tissue regeneration. This combination has been shown to enhance cellular signaling and tissue repair. This study aimed to analyze the characterization of collagen-chitosan hydrogels with I-PRF and determine the growth factor release pattern that occurs after mixing.Collagen-chitosan hydrogels were prepared and combined with I-PRF at a 1:1 ratio. The structural characterization of these hydrogels, both with and without I-PRF, was performed using Fourier transform infrared spectroscopy (FTIR), enabling the comparison of absorption bands. Furthermore, the release profiles of transforming growth factor-beta 1 (TGF-β1) and platelet-derived growth factor AB (PDGF-AB) were assessed in two experimental groups: The first group consisted of I-PRF alone, while the second group comprised of I-PRF combined with collagen-chitosan hydrogels. Growth factor release was evaluated at multiple time points (days 1, 3, 5, 7, 9, 11, 13, 15, and 17) using enzyme-linked immunosorbent assay. The resulting absorbance values were converted into concentration measurements (pg/mL) using a standard calibration curve. Statistical analysis was conducted using two-way analysis of variance followed by a post hoc least significant difference test.FTIR analysis demonstrated that the functional groups present in the collagen-chitosan hydrogel remained unchanged following the incorporation of I-PRF, confirming the formation of physical rather than chemical bonds. Subsequent analysis revealed statistically significant differences in the release patterns of TGF-β1 and PDGF-AB between the two groups (p < 0.05). The combination of collagen-chitosan hydrogel and I-PRF exhibited a more stable and sustained release profile from day 1 to day 17.The combination of I-PRF with collagen-chitosan hydrogels does not alter the fundamental chemical structure of the scaffold. However, this combination does influence the controlled release of growth factors. This finding indicates that the synergistic interaction between collagen and chitosan enhances the hydrogel's properties, suggesting its potential as a promising biomaterial for use as a scaffold in bone regeneration.

The objectives were to synthesize a bioactive nanocomposite as an endodontic antimicrobial agent by loading previously synthesized electrosprayed chitosan nanoparticles (Ch-Np) into Zeolite-Y as a carrier and compare its antimicrobial activity against two endodontic pathogens using the agar diffusion test. Additionally, the effect of tissue inhibitors (dentin powder and serum albumin) on the antimicrobial activity of the Ch-Np-Zeolite nanocomposite was studied. Finally, the possible cytotoxicity of the novel nanocomposite against Balb/c 3T3 mouse fibroblast cells was evaluated.A concentration of 3% (w/v) electrosprayed Ch-Np was mixed with Zeolite-Y in a concentration of 53.3 (w/v) and characterized using high-resolution scanning electron microscopy (HR-SEM) and energy-dispersive X-ray spectroscopy (EDS) analysis. The antimicrobial activity was evaluated against Streptococcus mutans and Enterococcus faecalis using the agar diffusion test, and the time-kill test was performed using the broth microdilution technique in the presence of tissue inhibitors. The cytotoxicity was evaluated against 3T3 mouse fibroblast cells using the standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.The difference between the antimicrobial activity of Ch-Np-Zeolite nanocomposite against S. mutans and E. faecalis was analyzed using the Mann-Whitney's U test. The effect of tissue inhibitors on the antimicrobial activity of Ch-Np-Zeolite nanocomposite was analyzed by comparing the mean of log colony-forming unit per milliliter over time. For the cytotoxicity assay, a statistically significant difference between each group and their control was made using a t-test with a probability value of p ≤ 0.05, considered a significant difference.HR-SEM of the dried paste-like mixture Ch-Np-Zeolite revealed the typical crystal habit of the supporting zeolite, and EDS analysis confirmed that the zeolite parent material retained its elemental composition after loading with Ch-Np. The antimicrobial activity of Ch-Np-Zeolite was demonstrated by the mean diameter inhibition zones of 9.57 and 7.85 mm for S. mutans and E. faecalis, respectively. Streptococcus mutans and E. faecalis were completely eradicated in the presence of tissue inhibitors. The Ch-Np-Zeolite nanocomposite significantly promoted the growth of 3T3 fibroblast cells (p < 0.05), supporting its lack of cytotoxicity.Zeolite-Y-loaded Ch-Np nanocomposite shows promising antimicrobial activity while maintaining its biocompatibility even in the presence of tissue inhibitors.