Search Results (1,674)

The durability of dental restorations against erosive and staining challenges is crucial for long-term clinical success. Therefore, this in vitro study aimed to investigate the combined effects of sequential simulated gastric acid exposure, coffee immersion, and different cleaning procedures on the surface roughness and color stability of four contemporary flowable resin composites with different filler and matrix characteristics. Ninety-six disk-shaped specimens were fabricated from four resin composites: Omnichroma Flow, G-ænial Universal Injectable, Universal Flo, and EverX Flow. Baseline surface roughness and color coordinates were recorded. Specimens were immersed in 0.06 M hydrochloric acid for 48 h to simulate gastric acid exposure and subsequently immersed in coffee solution for 24 h to simulate staining. Color measurements were performed at baseline, after sequential gastric acid–coffee exposure, and after cleaning procedures. ΔE₀ was calculated between baseline and post-exposure values, whereas ΔE₁ was calculated between post-exposure and post-cleaning values. Specimens were then allocated to three cleaning subgroups: toothbrushing (BR), water flosser (WF) and mouthrinse (MR). Final surface roughness and color changes were evaluated. Data were analyzed using mixed and factorial ANOVA tests. Sequential gastric acid–coffee exposure significantly increased surface roughness in all materials. Omnichroma Flow showed the lowest roughness values, whereas G-ænial Universal Injectable demonstrated the highest post-treatment roughness, particularly after toothbrushing. Toothbrushing generally caused greater roughness increases than other cleaning procedures. Material type significantly affected color stability, with Universal Flo showing the greatest discoloration and Omnichroma Flow the lowest color change. Surface roughness and color stability were significantly influenced by sequential gastric acid–coffee exposure and cleaning procedures in a material-dependent manner. Full article

Periodontitis, a chronic inflammatory disease affecting approximately 40% of U.S. adults aged 30 years and older, is characterized by dysbiosis of the dental plaque microbiome. However, although scaling and root planing (SRP) is the cornerstone of periodontal treatment, its effects on the taxonomic composition and functional potential of the dental plaque microbiome remain incompletely understood. In this study, we used whole-metagenome shotgun sequencing to characterize taxonomic composition and functional potential in dental plaque microbiomes collected from 39 patients with Stage II or III generalized periodontitis before and 3–4 months after SRP. Consistent with clinical improvement, periodontal therapy significantly reduced probing depth, clinical attachment level, bleeding on probing, and plaque index. Whole-metagenome shotgun sequencing identified 3.18 million non-redundant genes and 12,353 microbial species across 78 samples, revealing increased gene and species richness after treatment, along with a significant restructuring of the microbial community. Established periodontal pathogens, including Porphyromonas gingivalis, as well as the emerging pathogens Escherichia coli and Burkholderia multivorans, decreased following treatment. Tannerella forsythia also showed a marked reduction after treatment, although this decrease was not significant after false discovery rate (FDR) correction. In contrast, health-associated early colonizers, including multiple Actinomyces species and Streptococcus cristatus, increased. Functional annotation using the Carbohydrate-Active Enzymes (CAZy) database identified significant treatment-associated differences in carbohydrate-active enzymes, including multiple glycosyltransferases, indicating remodeling of the predicted functional potential of the dental plaque microbiome. These findings demonstrate that successful SRP promotes coordinated taxonomic and predicted functional remodeling of the dental plaque microbiome and highlight the value of shotgun metagenomic sequencing for characterizing both taxonomic and functional recovery following periodontal therapy. Full article

Background/Objectives: Menopause is a complex physiological transition characterized by progressive estrogen deficiency and systemic biological changes that can affect multiple organs and tissues, including the oral cavity. Growing evidence suggests that hormonal fluctuations during the menopausal transition may influence periodontal health, salivary function, oral sensory perception, and overall oral health-related quality of life. Objective: This narrative review aims to provide a comprehensive overview of the biological mechanisms and clinical manifestations associated with the relationship between menopause and oral health, with particular attention to periodontal outcomes, salivary changes, oral discomfort, dental status, and the potential role of hormone replacement therapy (HRT). Methods: This narrative review was based on a structured literature search conducted in PubMed/MEDLINE and Scopus to identify studies published between January 2005 and May 2026. Predefined eligibility criteria were applied to identify relevant human studies. The retrieved evidence was synthesized narratively according to major oral health domains and menopausal phenotypes. Results: Fifty studies met the inclusion criteria. Overall, menopause was associated with poorer periodontal parameters, including increased probing depth, clinical attachment loss, and periodontal inflammation. Reduced salivary flow, dry mouth, altered salivary composition, burning symptoms, and taste disturbances were frequently reported in peri- and postmenopausal women. A higher prevalence of caries and tooth loss was also reported, although the contribution of age and other confounding factors varied across studies. New evidence suggests that estrogen deficiency may influence oral health through interconnected pathways involving immune regulation, bone metabolism, salivary gland function, and host–microbiome interactions. Evidence regarding the effects of HRT has been mixed, although several studies have reported improvements in salivary function and periodontal outcomes among treated women. Conclusions: Menopause appears to act as an important systemic modifier of oral health through multifactorial biological mechanisms. Menopause-associated oral manifestations go beyond local tissue changes and reflect broader interactions between hormonal status, inflammation, bone metabolism, and microbial ecology. Increased awareness among dental and medical professionals and a multidisciplinary approach could improve the prevention, diagnosis, and management of oral diseases in postmenopausal women. Further, well-designed longitudinal studies are needed to clarify causal relationships and identify effective therapeutic strategies. Full article

Material selection is crucial to hard tissue regeneration, and matching scaffold properties to those of the target tissue can improve clinical outcomes. This study compared the physicochemical, mechanical, and biological performance of fibrous scaffolds fabricated from polycaprolactone (PCL), polydioxanone (PDO), and gelatin methacryloyl (GelMA) for hard tissue regeneration. Polymeric fibers were produced by electrospinning, and their morphological, physical, and mechanical properties were characterized by scanning electron microscopy (SEM, n = 2), swelling and degradation analyses (n = 8), water contact angle measurements (n = 16), and tensile testing (n = 8). In addition, periodontal ligament stem cells (PDLSCs), alveolar bone marrow stem cells (aBMSCs), and dental pulp stem cells (DPSCs) were seeded onto the scaffolds to evaluate cell spreading (n = 4), viability (n = 8), and mineralized matrix formation (n = 6). Data were analyzed using one- or two-way ANOVA followed by appropriate post hoc tests (α = 5%). All polymers formed homogeneous fibrous scaffolds, with diameters within the nanoscale range. PDO and GelMA showed higher swelling than PCL, while PCL retained approximately 95% of its initial mass after three months. PCL and PDO showed higher elongation at break, tensile strength, and Young’s modulus than GelMA. Both PDO and GelMA displayed contact angles below 90°, with GelMA showing the lowest values. In vitro, all polymers were cytocompatible: PDO and GelMA enhanced DPSC viability at 7 days, whereas GelMA produced the highest viability for PDLSCs and aBMSCs at that time point. GelMA also promoted the highest mineralized matrix formation for DPSCs and PDLSCs, with no significant differences among polymers for aBMSCs. Overall, GelMA scaffolds promoted greater cell viability and mineralized matrix formation, while PCL and PDO provided superior mechanical properties, highlighting the importance of balancing biological and mechanical requirements when designing scaffolds for hard tissue regeneration. Full article

This study evaluated the effect of sports and energy drinks on the surface roughness of three commonly used restorative dental materials: resin-based composites (RBCs), resin-modified glass ionomer cements (RMGICs), and conventional glass ionomer cements (GICs). Sixty-three A2-shade specimens of each material were fabricated, stored in distilled water for 24 h, and then immersed in six commercially available beverages or distilled water (control) for 6, 30, or 60 h. Surface roughness was assessed after each immersion period using contact profilometry, and the effects of material type, immersion medium, and exposure time were compared. Surface roughness increased with longer immersion times for all materials, although the magnitude of change varied significantly among material types. RBCs showed the greatest resistance to surface degradation, whereas RMGICs and particularly GICs exhibited progressively higher roughness values over time. Beverages generally produced greater surface roughness than distilled water, with sugar-containing formulations showing higher roughness values than their sugar-free counterparts. Prolonged exposure to sports and energy drinks may adversely affect the surface integrity of restorative materials. Resin-based composites demonstrated the highest resistance to roughness changes, whereas glass ionomer cements were the most susceptible. Increased surface roughness may contribute to plaque accumulation, staining, and material wear, potentially compromising the long-term clinical performance of restorations. Full article

Polyetheretherketone (PEEK) has emerged as a promising biomaterial for orthopedic and craniofacial implants due to its favorable mechanical properties and fatigue resistance; however, its inherent chemical inertness limits effective osseointegration. In this study, femtosecond laser surface modification is explored as a strategy to enhance the bioactivity of PEEK. Based on a previously performed parametric study, controlled micro- and nanoscale surface textures were fabricated using femtosecond laser processing, enabling precise tuning of surface roughness and wettability without the need for additional chemical treatment. The modified surfaces were systematically characterized in terms of morphology, composition, and topography using scanning electron microscopy (SEM), 3D profilometry, and water contact angle measurements. Four optimized femtosecond laser-generated surface architectures were selected for the present investigation and comprehensively characterized, followed by in vitro evaluation of dental pulp stem cell adhesion, morphology, and proliferation. The results indicate that laser-induced micro/nanostructuring enhances the surface properties of PEEK, while supporting cellular attachment and favorable cell–surface interaction. Differences in the biological response were observed among the optimized laser-textured surfaces. These findings highlight the feasibility of femtosecond laser texturing as a clean, reproducible, and scalable approach for the development of next-generation, personalized orthopedic implants. Full article

The study aimed to develop and preliminarily characterize experimental resin-based dental composites (RBCs). In addition to the composites, didodecyldimethylammonium bromide (DDAB) was used as a biocide in various concentrations (0–3 wt%). Hardness (HV), flexural strength (FS), and modulus of elasticity, as well as diametral tensile strength (DTS) of composites, were examined. Additionally, shrinkage stress, surface free energy (SFE), water sorption (Wsp), and solubility (Wsl) were determined. Cytometric analysis, including biocidal surface testing and susceptibility to colonization by Streptococcus mutans, Escherichia coli, and Candida albicans, assessed antibacterial activity. The HV of RBCs varied from 27.2 ± 1.5 to 31.5 ± 1.8 depending on DDAB amount, FS—67.0 ± 16.1 MPa for control composite and 79.2 ± 14.5 MPa for modified composite. All DTS values exceed 24 MPa. Shrinkage stress is highest for the composite with 0.25 wt% DDAB—18.5 ± 1.9 MPa—and lowest for the composite with 1 wt% DDAB—15.0 ± 2.5 MPa. Wsp is lowest in the control group (37.19 ± 1.69 µg/mm³) and highest for 1 wt% modifier (42.11 ± 2.75 µg/mm³). Wsl was at its lowest in control group (1.98 ± 1.58 µg/mm³), and highest for modification with 1 wt% (3.91 ± 1.74 µg/mm³). For RBCs modified with 3 wt% DDAB after 60 min, an increase in dead cells is observed: 51% for Escherichia coli, 71% for Streptococcus mutans, and 24% for Candida albicans. Preliminary results show that DDAB effectively reduced the presence of the tested pathogens and contraction stress; however, at certain concentrations it negatively influences hardness and water sorption of composites. The presented findings highlight both the potential and the limitations of DDAB-modified RBCs and underline the need for further studies, including cytotoxicity and genotoxicity assessments, release analyses and evaluation of composites’ ageing behavior. Full article

The objective of this study was to evaluate the antioxidant and antibacterial profiles of Picea orientalis (Oriental spruce) resin extracts collected from three distinct geographical sites (Artvin, Borçka, and Çaykara) within the Eastern Black Sea region of Türkiye. Additionally, it aimed to assess the viability of these extracts as natural antibacterial agents against cariogenic pathogens and to determine their subsequent effect on dental bond strength performance. Quantitative phytochemical analysis of the ethanolic extracts included the determination of total phenolic content, coupled with individual phenolic profiling by HPLC-PDA. The antioxidant potential was assessed through DPPH and FRAP assays. Additionally, the antibacterial activity against a panel of oral and systemic pathogens was evaluated using agar well diffusion. Furthermore, to evaluate mechanical performance, composite bond strengths were tested on 180 dentin specimens using both self-etch and etch-and-rinse adhesive strategies, following cavity pre-treatment with a control, chlorhexidine, or the resin extracts. The results revealed that the resin from the Artvin region exhibited the highest phenolic content, characterized by an abundance of trans-cinnamic, caffeic, and ferulic acids, which correlated with their superior antioxidant capacity. Furthermore, while the extracts demonstrated potent inhibitory effects against Staphylococcus aureus, their antibacterial activity against Streptococcus mutans was found to be comparatively moderate. In bond strength evaluations, the non-aged control group exhibited the highest values (p = 0.000); however, no statistically significant difference was observed between the chlorhexidine and resin extract groups (p > 0.05). Consequently, the phenolic-rich P. orientalis resin represents a promising natural antibacterial alternative for dental applications. Full article

Background/Objectives: This study aimed to evaluate the direct effect of elements released from dental casting alloys on human gingival fibroblasts (HGF). Methods: Ten discs each of commercially pure titanium (Ti), silver-palladium (Ag-Pd), and nickel-chromium (Ni-Cr) alloys, measuring 4 mm in diameter and 3 mm in thickness, were fabricated and placed directly on HGF cultures for 72 h. Five discs from each alloy group were incubated in DMEM, whereas the remaining five discs were incubated in artificial saliva. Cytotoxicity was assessed using three in vitro methods: morphological evaluation of HGF, the dye exclusion test (DET), and the methyl-thiazolyl-tetrazolium (MTT) colorimetric assay. Results: HGF directly exposed to cpTi, Ag-Pd, and Ni-Cr discs demonstrated reduced cell density around the alloy specimens compared with untreated control cells after 72 h of incubation in both DMEM and artificial saliva. cpTi alloy exhibited no detectable cytotoxic effects, whereas Ag-Pd and Ni-Cr alloys demonstrated cytotoxicity in both DMEM and artificial saliva under the experimental conditions. Among the tested alloys, Ni-Cr exhibited the highest cytotoxicity. Artificial saliva enhanced the cytotoxic effects of the tested alloys, as evidenced by increased morphological alterations, reduced cell viability, and lower MTT activity compared with DMEM. Conclusions: cpTi alloy exhibited the lowest direct cytotoxic effect on HGF in both DMEM and artificial saliva. In contrast, Ag-Pd and Ni-Cr alloys demonstrated greater cytotoxicity, particularly in the presence of artificial saliva, suggesting that both alloy composition and the surrounding environment influence the biological response of oral soft tissues. Full article

Directing a stream of air across the tooth when light curing resin-based composites (RBCs) may affect their degree of conversion (DC), maximum rate of polymerization (RP_max), and in vitro intrapulpal temperature. Methods: Filtek One Bulk Fill and VisCalor bulk were preheated according to the manufacturer’s instructions and used to fill a Class I cavity in a molar at 32 °C. A stream of air at either 15 or 30 psi was directed across the tooth from an air-water syringe positioned 1 cm from the buccal surface. The RBCs were light-cured for 20 s using the Bluephase N, and the DC and RP_max were determined from real-time FT-IR data. A T-type thermocouple positioned inside the pulp chamber recorded the temperature. DC and RP_max data were analyzed using one-way ANOVA, whereas temperature was analyzed using two-way ANOVA, followed by Tukey post hoc tests. Results: Directing a stream of air at the tooth produced no significant differences in the DC and RP_max. The temperature change (ΔT) decreased compared to when no air was delivered. No significant difference in ΔT was found between the two air pressures. Conclusions: Directing a stream of air across the tooth when the preheated RBC was inserted did not affect the polymerization kinetics. The air stream reduced the temperature rise inside the pulp chamber as the RBC was light-cured. Clinical Significance: Directing a stream of air across the tooth at either 15 psi or 30 psi during light curing is an easy method to reduce the temperature increase inside the pulp chamber without affecting the polymerization kinetics of the evaluated preheated RBCs in this in vitro model. Full article

Background and Objectives: Long-standing contact between oral mucosa and restorative materials may be associated with adaptive epithelial and stromal remodeling. This study evaluated non-dysplastic epithelial plasticity in the oral mucosa adjacent to long-term restorative materials. Materials and Methods: This retrospective study included 150 formalin-fixed, paraffin-embedded oral mucosal specimens divided into five groups: control, dental amalgam, methacrylate-based resin composite, clinically documented all-ceramic restorations, and metallic/metal–ceramic restorations (n = 30 each). Exposed cases had documented mucosal adjacency or repetitive contact with a dominant restorative material for at least 5 years. Histopathological parameters, CK19, Ki67, p53, and COX-2 expression were assessed, and MAERS was calculated. Statistical significance was set at p < 0.05. Results: MAERS differed significantly among groups (p < 0.001), with the highest mean values in metallic/metal–ceramic specimens (10.3 ± 2.4) and dental amalgam specimens (9.7 ± 2.1), intermediate values in resin composite specimens (7.1 ± 1.8), and the lowest values in all-ceramic (5.0 ± 1.4) and control specimens (4.8 ± 1.3). Suprabasal CK19 redistribution was observed in 22/30 metallic/metal–ceramic specimens (73.3%) and 20/30 amalgam specimens (66.7%), elevated Ki67 expression in 22/30 (73.3%) and 19/30 (63.3%), and moderate-to-strong COX-2 expression in 21/30 (70.0%) and 19/30 (63.3%), respectively. p53 expression was heterogeneous and did not show dominant, strong, or diffuse overexpression. Conclusions: Metallic/metal–ceramic restorations showed the highest remodeling burden, dental amalgam showed a similarly high profile, resin composite showed an intermediate profile, and all-ceramic-associated mucosa remained close to control specimens. These findings suggest material-dependent, inflammation-associated epithelial plasticity without evidence of epithelial dysplasia. Full article

The ongoing development of subtractive options for indirect restorations places clinicians in a position that requires adaptation, understanding and choosing of the most suitable option for the long-term survival of the restoration. Mechanical parameters represent important indicators of long-term success. Consequently, this research aimed to assess the impact of water sorption on the mechanical properties of two direct resin composites, Gradia Direct Anterior A2 and Filtek Z550 A2 and three CAD/CAM subtractively manufactured dental resin composites, Vita Enamic, Brilliant and Cerasmart. A total of one hundred specimens (50 control, 50 underwent this protocol: dehydration, immersion in distilled water for 30 days and then re-desiccation), standardized to the dimensions of 14 mm × 4 mm × 1.2 mm were subjected to three-point bending test (based on ISO 4049:2019 and ISO 6872:2015), in order to find out the flexural strength and the elastic modulus of the material at the breaking point. Then, the fractured sample surfaces were fractographical analyzed. Using the two-parameter Weibull approach, the Weibull modulus (m) and the characteristic strength (σ₀) were evaluated. In this investigation, the elastic modulus varied from 5.8 (Gradia Control) to 20.31 (Vita Degraded) GPa, with the upper limit close to the values of natural dentin (17.7–29.8 GPa). The values of flexural strength ranged from 174.47 (Brilliant Control) to 79.2 (Gradia Control), subtractively processed materials demonstrating higher flexural strength and elastic modulus values than the direct resin composites, which is related to their high inorganic filler content. All material groups, except for Gradia Control, had a flexural strength more than the 80 MPa minimum value needed to sustain masticatory force. The dehydration and hydration cycles did not have a statistically significant influence on the mechanical properties of the material. The fractographic analysis revealed fracture patterns and features associated with the microstructure, with the PICN category material being particularly notable. Weibull analysis revealed that the direct resin composite materials exhibited higher reliability, lower data scatter and CAD-CAM materials showed greater characteristic strength, with a notably high performance of the nano-hybrid direct resin composite. Full article

Historically, the study of oral fungal species was limited by the inability to cultivate most of them. However, advances in metagenomic techniques have enabled the direct identification of microbial genomes from human samples, markedly broadening our understanding of the oral mycobiome. This narrative review aims to analyze the available scientific evidence on the composition and dynamics of the oral mycobiome, as well as its influence on the development of local pathological conditions. The oral mycobiome is highly diverse, with emphasis on genus Candida, followed by Cladosporium, Aureobasidium and Saccharomyces. Candida albicans remains the most frequently identified species in both health and diseases state. However, individuals with oral candidiasis present a higher detection of Candida dubliniensis, Candida parapsilosis, Pichia kudriavzevii, Antrodiella micra and Cladosporium sphaerospermum. In dental caries, C. albicans and C. dubliniensis are associated with advanced lesions, whereas Debaryomyces and Rhodotorula may exert protective effects against Streptococcus mutans, a cariogenic bacterium. In periodontitis, an increase in yeast-bacteria interactions is observed. Additionally, C. albicans has been implicated in oral carcinogenesis through multiple mechanisms. These findings highlight the need for a deeper understanding of the oral mycobiome to enable early detection of oral diseases and the development of therapeutic approaches. Full article

The radiopacity of adhesives is important for radiographic diagnosis and micro-computed tomography (micro-CT) evaluation of adhesive restorations. However, most universal adhesives lack sufficient radiopacity. This study examined the radiopacity and intracavity distribution of four universal adhesives—Scotchbond Universal Adhesive (SBU), Scotchbond Universal Plus Adhesive (SBP), Clearfil Universal Bond Quick ER (UBQ), and G-Premio Bond (GPB)—using a cylindrical cavity model. Cavities were prepared in bovine enamel–dentin blocks and scanned using micro-CT at 5.0 μm/voxel after cavity preparation, adhesive application, and resin composite filling (n = 3). The adhesive layer region was geometrically defined from sequential datasets and analyzed using actual 16-bit grayscale values. Grayscale values, adhesive layer thickness, and composite-filling-induced volume changes were evaluated by three-dimensional difference analysis. SBP showed a grayscale value equivalent to that of dentin, whereas SBU, UBQ, and GPB were statistically indistinguishable from air. Adhesive thickness increased from the lateral walls to the cavity floor, and reduced-density regions were observed in UBQ and GPB. Therefore, SBP was the only tested universal adhesive with dentin-equivalent radiopacity, enabling reliable micro-CT evaluation and reducing the risk of radiographic misdiagnosis. The proposed grayscale-based approach may support future non-destructive investigations of dental adhesive behavior. Full article

Tooth avulsion is one of the most severe dental injuries, and appropriate storage media are essential for preserving avulsed teeth before replantation. However, little is known about the effects of these media on the color stability of existing restorative materials. This in vitro study evaluated the color stability of a composite resin and a glass hybrid restorative material immersed in six storage media commonly recommended for avulsed teeth. A total of 120 disc-shaped specimens were prepared and allocated to dry environment, artificial saliva, tap water, cow’s milk, goat milk, and kefir groups. Color measurements were performed using the CIE L*a*b* system at baseline, 30 min, 1 h, 6 h, 12 h, and 24 h, and color change (ΔE) values were calculated. Data were analyzed using a linear mixed-effects model with restorative material, storage medium, and time as fixed effects and specimen ID as a random effect. Color change increased significantly over time in all groups (p < 0.001). Glass hybrid restorations exhibited significantly higher ΔE values than composite restorations across most storage media and time points (p < 0.001). Significant material–medium–time interactions were observed (p < 0.001), indicating that the effects of storage media varied according to restorative material and exposure duration. Dry storage conditions were generally associated with the highest color changes. Within the limitations of this study, the tested composite restorative material (G-ænial Posterior) demonstrated greater short-term color stability than the tested glass hybrid restorative material (EQUIA Forte HT) in the evaluated storage media. Full article