Journal of Applied Oral Science最新文献

Background: Streptococcus mutans serotypes (c, e, f, k) are linked to dental caries, with less common serotypes (e, f, k) and collagen-binding genes (CBG: cnm and cbm) suggested to be associated with cardiovascular diseases.

Objective: This study investigated the presence of S. mutans serotypes and collagen-binding genes (CBGs) in dental plaque and their possible association with acute myocardial infarction (AMI) in adults.

Methodology: A total of 31 infarcted and 17 non-infarcted patients underwent oral and blood examinations. DNA from plaque samples was analyzed using PCR to identify S. mutans serotypes and cnm/cbm genes. S. mutans was detected in 22.6% (7/31) of infarcted patients and 11.8% (2/17) of non-infarcted patients.

Results: Serotype c was the most prevalent in infarcted patients (57.1%, 4/7), followed by e (42.9%, 3/7) and k (14.3%, 1/7); serotype f was not detected. Only serotype c was found in non-infarcted patients. Less common serotypes (e, k) and co-occurring serotypes (c, k) were exclusive to infarcted patients. No CBGs were detected in any serotypes. No association was found between S. mutans and dental caries in either group. Patients with cholesterol levels <190 mg/dL and no S. mutans had a 47.4% lower risk of infarction.

Conclusion: Although S. mutans, including less common serotypes, was more prevalent in infarcted patients, no significant association with AMI was observed. Further research is needed to elucidate the role of S. mutans in cardiovascular diseases.

Micro-nano bioactive glass (MNBG) has bone regenerative potential. However, the difficulty of MNBG molding restricts its clinical applications in bone regeneration. Exosomes carry proteins, lipids, and nucleic acids for communication between cells. In this study, we adhered human exfoliated deciduous teeth (SHED)-derived exosomes (SHED-Exos) to electrospun micro-nano bioactive glass/polycaprolactone (MNBG/PCL) membrane to control inflammation and promote bone regeneration. MNBG/PCL membrane showed biocompatibility and osteogenic ability. Next, we demonstrated that SHED-Exos internalized into macrophages attenuated LPS-induced expression of M1-macrophage markers iNOS, IL-6, and IL-1β and upregulated M2-macrophage marker IL-10 expression, indicating a switch from M1 to M2 macrophage phenotype. MNBG/PCL-loaded SHED-Exos membrane supported the survival and growth of mouse bone marrow stromal cells (mBMSCs). When M1 macrophages were co-cultured with mBMSCs on the membrane, the SHED-Exos-loaded membrane showed higher Runx2, Alp, and Ocn gene expression. Our findings indicate that SHED-Exos-functionalized MNBG/PCL membrane has anti-inflammatory and osteoinductive potential, suggesting its potential as a candidate material for bone regeneration.

Objective: This study evaluated the clinical relevance of EBI3 polymorphisms, along with tumor Epstein-Barr virus (EBV) and Human Cytomegalovirus (HCMV) status, in prognostically adverse HPV-negative OSCCs.

Methodology: EBI3 (rs4740, rs4905, rs428253) genotyping was performed by qPCR in 95 HPV-negative OSCC patients and 108 age- and sex-matched controls. Tumor HPV, EBV, and HCMV status were assessed by qPCR. EBV viral load was calculated by exponential approach and a relative estimate of EBV copies per 105 cells. Associations with overall survival (OS) and recurrence-free survival (RFS) were evaluated by Kaplan-Meier and Cox regression analyses.

Results: EBV-positive tumors showed a significant association with increasing nodal stage (P=0.020). EBV viral load stratification (negative, low, high) presented a non-significant trend toward association with advanced tumor stage (P=0.060). Notably, EBI3 rs428253 predicted worse OS in EBV-positive patients, whereas rs4740 and rs4905 variants were associated with advanced tumor stage (P=0.024 and P=0.018). rs4740 and rs4905 variants were inversely associated with OSCC risk in dominant and overdominant models. Analysis detected HCMV in 7.4% of tumors but was not clinically relevant.

Conclusions: EBI3 genetic variants and EBV status may have prognostic relevance in HPV-negative OSCC. EBV may interact with the host genetics to influence nodal metastases and outcomes, suggesting a potential EBV-EBI3 axis, which warrants further investigation. Future precision oncology approaches may incorporate host and viral genetic markers to identify and stratify high-risk HPV-negative OSCC patients.

Background: Paracoccidioidomycosis is a systemic mycosis caused by the dimorphic fungus Paracoccidioides brasiliensis and related species, which are endemic to Latin America. Oral manifestations are highly relevant for diagnosis, representing the primary anatomical site biopsied for confirmation.

Objective: To investigate whether the virulence of P. brasiliensis influences the levels of circulating antigen in susceptible (B10.A) and resistant (A/Sn) murine models at multiple post-infection time points. The presence of oral lesions and their correlation with antigenemia were also assessed.

Methodology: One-week-old female B10.A and A/Sn mice were inoculated with the P. brasiliensis lineages Pb18 or Pb265, whereas controls received sterile saline. At four, eight, 12, and 16 post-inoculation weeks, sera were collected via sub-axillary plexus incision under anesthesia. Circulating antigen levels were quantified using competitive ELISA. Specific antibody titers were determined by indirect non-competitive ELISA and P. brasiliensis antigens. Intergroup comparisons were performed using two-way ANOVA, followed by multiple comparisons. Oral cavities were visually examined by three independent evaluators to find mulberry stomatitis. Prevalence was expressed as the percentage of affected animals.

Results: Significant differences in the circulating antigen levels were detected between susceptible mice infected with Pb18 and Pb265 and between susceptible and resistant mice infected with Pb18 16 weeks after inoculation. The highest levels of antibodies were found when both B10.A and A/Sn mice were infected with Pb18. During infection, no mice showed mulberry-like lesions in the oral cavity.

Conclusion: The virulence of the infecting P. brasiliensis strain, although not specifically linked to the gp43 antigen, plays a critical role in antigenemia. Despite absent oral lesions-an inherent limitation of this murine model-this study provides relevant insights into the relationship between fungal virulence and circulating antigen levels.

Objective: To evaluate the formation of mixed-species biofilms of Candida albicans and methicillin-sensitive Staphylococcus aureus (MSSA) on the surface of a 3D-printed denture base resin, as well as its surface properties, under varying printing parameters.

Methodology: Discs (n=40 per group, 10×1.2 mm) of a denture base resin (priZma 3D Bio Denture) were fabricated using two 3D-printers-Liquid Crystal Display (LCD) and Digital Light Processing (DLP)-at three different angles (0°, 45°, or 90°). Surface roughness was measured using a digital profilometer and expressed as Ra (µm). For surface energy (SE) analysis, contact angles were measured using a tensiometer. Discs were incubated at 37 °C for 90 minutes and 48 hours to enable biofilm formation using C. albicans and MSSA inocula. Cell viability was assessed by colony-forming unit (CFU/mL) counts, and metabolic activity was evaluated using the XTT assay (absorbance). Microbial counts and XTT results were analyzed by three-way ANOVA (printer type, printing angle, incubation period). Surface roughness was analyzed by two-way ANOVA (printer type, printing angle), with Tukey's test and a significance level of 0.05.

Results: For both CFU/mL and XTT assays, incubation period was the only significant factor (p<0.001 and p=0.006, respectively), while other factors and interactions were not statistically significant (p>0.05). Surface roughness was significantly influenced by printer type, printing angle, and their interaction (p=0.027). The LCD 0° and LCD 90° groups produced smoother surfaces compared with LCD 45° (p=0.002), which showed similar values to all DLP groups regardless of angle (p>0.05). The DLP printer did not show significant roughness variations across the tested angles (p>0.05). The LCD groups presented numerically lower SE values compared to the DLP groups.

Conclusion: The LCD system performs better than DLP in reducing surface roughness at 0° and 90°. Moreover, the analyzed factors did not significantly affect microbial adhesion or the formation of mixed-species biofilms.

Composite resins containing S-PRG fillers may degrade under pH fluctuations and abrasion, influenced by their composition, particle size, exposure time, and solution acidity.

Objective: This study evaluated the ability of resin composites containing S-PRG fillers to modulate the pH of the surrounding medium, as well as their surface roughness and gloss following an erosive/abrasive challenge.

Methodology: Resin disks (⌀4mm × 2mm) (n=15) were prepared using Filtek Z350 XT (control), Beautifil II, Beautifil II Enamel, and Beautifil II LS (the latter three containing S-PRG fillers). To assess buffering capacity, disks (n=5) were immersed in a demineralizing solution, and pH was measured at baseline and after 1, 3, 7, 14, and 21 days. Separate specimens (n=10) underwent daily erosion cycles using 0.3% citric acid, combined with abrasion via toothbrushing, conducted over a 5-day period to simulate an acidic diet and twice-daily oral hygiene. Surface roughness (Ra) and gloss (GU) were assessed at baseline, after polishing, and following the challenge; surface topography was analyzed by a scanning electron microscope (SEM). Data were analyzed using a generalized linear mixed model for repeated measures over time, in addition to Tukey-Kramer, Kruskal-Wallis, Dunn, Friedman, and Nemenyi tests (α=0.05).

Results: All materials showed a significant increase in the pH of the surrounding medium over time (p<0.05). After 24 hours, Beautifil II exhibited a significantly higher pH than the others (p<0.05). Filtek Z350 XT demonstrated lower surface roughness than the other materials after the erosive/abrasive challenge (p<0.0001). Following the challenge, Beautifil II and Beautifil II Enamel presented higher gloss values (p<0.05).

Conclusions: Resin composites containing S-PRG fillers slightly increased the pH of the surrounding medium over time. Surface roughness increased after the erosive/abrasive challenge, although the gloss of the S-PRG-containing composites also improved.

Objective: This study investigates the microstructural and mechanical characteristics of primary teeth affected by ROD.

Methodology: A total of two ROD-affected primary teeth from two different cases underwent clinical examinations. In addition to control samples of caries-free retained primary teeth, the affected samples were examined using micro-computed tomography (micro-CT), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and nanoindentation analysis.

Results: Clinical findings revealed yellowish discoloration, rough surfaces, and root resorption on the affected teeth. Radiographs indicated hypocalcified enamel, widened pulp chambers, and delayed development of permanent teeth. Micro-CT showed affected teeth with thinner and uneven enamel, disordered dentin, and reduced mineral density. XRD analysis found reduced crystallinity. SEM and TEM analyses revealed hypoplastic and loosely packed enamel crystals, whereas dentin exhibited disorganized collagen fibrils and poorly mineralized crystals. EDS analysis showed a reduced calcium/phosphorus ratio and an increased magnesium/calcium ratio in the affected enamel. Nanoindentation tests found reduced hardness and elastic modulus in ROD-affected enamel compared with control teeth.

Conclusion: ROD-affected primary teeth display significant microstructural abnormalities and compromised mechanical properties, underscoring the need for early intervention and long-term monitoring to prevent complications.

Objective: The incorporation of bioactive agents into resin-modified glass ionomer cement (RMGIC) is a promising strategy to improve its mechanical strength and biofilm control, especially for patients with active dental caries. This study aimed to evaluate the effects of incorporating ZnONPs and CaGP into RMGIC on its mechanical and microbiological properties.

Design: Six groups were tested: 1) RMGIC (without CaGP/ZnONPs); 2) RMGIC-1.0%ZnONPs; 3) RMGIC-2.0%ZnONPs; 4) RMGIC-3.0%CaGP; 5) RMGIC-3.0%CaGP-1.0%ZnONPs; and 6) RMGIC-3.0%CaGP-2.0%ZnONPs. The compressive strength (CS), diametral tensile strength (DTS), and surface hardness (SH) were evaluated after 24 hours and 7 days. Antimicrobial and antibiofilm activity were evaluated using agar diffusion and biofilm metabolic activity (XTT) assays.

Results: After 24 hours, all the groups showed similar DTS values (p>0.05), except for RMGIC-3.0%CaGP-1.0%ZnONPs, which showed the highest DTS value (p<0.05). Comparing 24 hours and 7 days, the DTS values of RMGIC-3.0%CaGP-2.0%ZnONPs, RMGIC-3.0%CaGP, and RMGIC-3.0%CaGP-2.0%ZnONPs were similar (p=0.360). After 24 hours, the RMGIC group showed the CS highest value, followed by RMGIC-2.0%ZnONPs (p < 0.05). After 7 days, the RMGIC-3.0%CaGP-1.0%ZnONPs group exhibited the highest CS value, approximately 15% higher than RMGIC (p<0.05). The RMGIC-1.0%ZnONPs group exhibited significantly higher SH at 24 hours (p=0.621). At 7 days, the highest SH value was observed for the RMGIC-3.0%CaGP-1.0%ZnONPs group (p<0.05). Regarding antimicrobial and antibiofilm activity, including results from biofilm metabolism assays, the RMGIC-3.0%CaGP-1.0%ZnONPs group demonstrated the most effective antimicrobial and inhibitory effects (p<0.05).

Conclusion: This study demonstrated that adding ZnONPs and CaGP to RMGIC enhanced its mechanical and antimicrobial and antibiofilm properties, suggesting enhanced mechanical performance and improved protection against cariogenic biofilms-critical factors for successful restorative treatments. Therefore, the addition of ZnONPs and CaGP is a promising strategy to develop advanced restorative materials that improve clinical outcomes, especially for patients with active dental caries.

Background: Vital pulp therapy is limited by incomplete dentin regeneration and dose-limiting toxicities of current histone deacetylase (HDAC) inhibitors. Previous structural studies have identified critical determinants of HDAC4-silencing mediator for retinoid and thyroid hormone receptor (SMRT) protein interactions, providing a rationale for developing selective inhibition strategies.

Objective: This study evaluated SMRT peptide 1-protein transduction domain (SP1-PTD), which is a cell-penetrating peptide designed to selectively disrupt HDAC4-SMRT interaction based on structural insights, for promoting odontoblast differentiation with improved safety compared to pan-HDAC inhibitors.

Methodology: SP1-PTD comprises an SMRT-derived sequence fused to a PTD, enabling targeted inhibition without affecting HDAC catalytic activity. Effects on odontoblast differentiation were assessed in murine dental papilla cell lines and primary human dental pulp cells using gene expression analysis, functional mineralization assays, and mechanistic studies including chromatin immunoprecipitation and RUNX2 acetylation analysis. Cytotoxicity was directly compared with suberoylanilide hydroxamic acid (SAHA) and trichostatin A.

Results: SP1-PTD treatment significantly enhanced odontoblast differentiation with 15.9-fold increase in dentin sialophosphoprotein (Dspp) expression alongside upregulation of RUNX2, osteocalcin, and bone sialoprotein. Functional analysis revealed 1.8-fold increased mineralization capacity. Mechanistically, SP1-PTD increased RUNX2 protein acetylation and histone acetylation at the Dspp promoter, indicating derepression of RUNX2-mediated transcription. Importantly, SP1-PTD did not show cytotoxicity across a wide therapeutic range (0.1-20 μM) and promoted cell proliferation, contrasting sharply with dose-dependent toxicity of pan-HDAC inhibitors. Direct comparison revealed SP1-PTD induced 14-fold increase in Dspp expression while SAHA suppressed it despite comparable Runx2 induction.

Conclusions: SP1-PTD represents a first-in-class selective HDAC4 inhibitor that achieves robust pro-differentiation effects with an exceptional safety profile. By specifically targeting HDAC4-SMRT interactions, SP1-PTD overcomes limitations of conventional HDAC inhibitors and offers translational promise for dental regenerative medicine.

Background: Fractalkine (CX3CL1) is expressed by various cells, contributing to the pathogenesis of diseases such as diabetes mellitus, vascular pathologies, and rheumatoid arthritis via immunological mechanisms. The CX3CL1-CX3CR1 axis regulates cellular responses such as proliferation and collagen production, which are implicated in gingival overgrowth (GO).

Objectives: This study aimed to assess the levels of CX3CL1, tumor necrosis factor-α (TNF-α), and transforming growth factor-beta (TGF-β) in both gingival crevicular fluid (GCF) and gingival tissues among patients with biofilm- and amlodipine-induced GO. Additionally, the potential relationship between these biomarkers and clinical periodontal parameters was evaluated.

Methods: The study included 17 participants with biofilm-induced GO (Group I), 18 participants with amlodipine-induced GO (Group A), and 10 systemically healthy participants without GO (Control). CX3CL1, TNF-α, and TGF-β levels in GCF samples were assessed using enzyme-linked immunosorbent assay (ELISA). Moreover, mRNA expression levels of CX3CL1, TNF-α, and TGF-β in tissue samples were determined by quantitative real-time PCR (qPCR).

Results: The total GCF CX3CL1 level was significantly higher in Group I and Group A compared to controls. However, tissue CX3CL1 and TNF-α levels were significantly higher in Group I than Group A (p<0.05). In Group A, total GCF CX3CL1 levels showed a positive correlation with the gingival index (GI) (r=0.644), bleeding on probing (BOP) (r=0.622), and GCF volume (r=0.720). A significant positive correlation was observed between tissue CX3CL1 and TNF-α levels (r=0.762) (p<0.05). In Group I, a significant correlation was observed between total GCF CX3CL1 and TNF-α, TGF-β, and GCF volume levels, respectively (r=0.865, r=0.845, r=0.651). A positive correlation (p<0.05) was also found between tissue CX3CL1 and TNF-α and TGF-β levels, respectively (r=0.689, r=0.903).

Conclusion: CX3CL1 may have a potential role in the development of GO-associated tissue fibrosis and its inflammatory mechanisms.