Archives of oral biology最新文献

Objective: The aim of this study was to investigate changes in the expression of members of the matrix metalloproteinases (MMPs) family in response to lipopolysaccharide (LPS) stimulation and to investigate the regulatory effects of BMP9 on MMPs.

Design: The extracted human stem cells from the apical papilla (hSCAPs) were identified by flow cytometry, Alizarin Red staining, Oil Red O staining, and alkaline phosphatase staining. The appropriate LPS concentration for inducing inflammation in hSCAPs was determined using real-time quantitative PCR (RT-qPCR) and Cell Counting Kit-8 (CCK-8) assays. MMP expression in LPS-stimulated hSCAPs was evaluated by RT-qPCR. BMP9 was overexpressed in hSCAPs via recombinant adenovirus, and its effects on MMP regulation were assessed using RT-qPCR, Western blotting, and ELISA. All experiments were conducted in vitro. Data were analyzed by one-way ANOVA followed by Tukey's post-hoc comparison, with p < 0.05 considered significant.

Results: The results showed that on the 3rd and 5th day after LPS stimulation, the expression of MMP-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-10, MMP-12, and MMP-13 in hSCAPs was significantly upregulated. On the 7th day after LPS induction, the expression of MMP-3, MMP-8, MMP-9 and MMP-13 in hSCAPs was significantly increased. When BMP9 was overexpressed in hSCAPs, the elevated MMPs were inhibited to varying degrees.

Conclusions: In the LPS-induced inflammatory environment, certain MMPs are elevated in hSCAP, with MMP-13 being the most significant. Overexpression of BMP9 can significantly inhibit elevated MMPs, suggesting that BMP9 may provide new insights and targets for the treatment of periapical periodontitis.

Objective: This study aimed to correlate occlusal marks on posterior teeth and cusp tips, recorded using an analog qualitative method, with digital evaluations of masseter and temporal muscle activity through electromyography indexes, comparing two normalization techniques (cotton and wax) using the standardized Percentage Overlap Coefficient of the Anterior Temporal muscle and Percentage Overlap Coefficient of the Masseter muscle indexes.

Design: This is a comparative cross-sectional observational study. Occlusal contact and electromyography records of the anterior temporal and masseter muscles were detected in 30 individuals with an average age of 34.9 years. During the electromyography examination, two repetitions of normalization were performed, each with maximum voluntary clenches of 5 seconds on cotton and on wax. The average electromyography amplitude was calculated from three repetitions for each material. According to the average obtained for each pair of muscles, the muscle activity index was calculated and correlated to the number of contacts, which were converted into percentages.

Results: Normalization with cotton showed a positive correlation between occlusal contacts and muscle activity (rs = 0.465, p = 0.010). The mean muscle activity index for cotton was 79.4 ± 13.9 for the masseter and 83.3 ± 9.2 for the temporal muscle, with no significant difference between the two muscles (p = 0.195). Normalization with wax showed better intra-subject repeatability with less than 5 % variation (masseter: 4.9 %, temporal: 4.2 %). There was no significant difference in muscle contraction between the different normalization materials (p = 0.902).

Conclusion: Both normalization methods demonstrated a variation of less than 10 %, with wax being considered more comfortable by the participants, indicating occlusal and muscular adaptation to the different methods. The results showed a positive correlation between posterior occlusal contacts and masticatory muscle activity, especially with cotton normalization, suggesting that occlusal contacts significantly influence muscle activity, potentially leading to muscle fatigue or hyperactivity.

Objectives: In this review, we provide an overview of the composition of the microbiota associated with these two dental pathologies, caries and tartar, highlighting the microbial profiles associated with each pathology.

Design: This literature review was carried out by a manual search of two electronic databases, PubMed and Web of Science (WOS), using specific keywords to the two oral pathologies dental caries and calculus.

Results: The oral microbial community is known for its complexity, and comprises hundreds of species of different micro-organisms. Many of them, under the influence of endogenous and exogenous factors, can play a role in the onset and development of oral pathologies. Analysis of the microbial profiles of caries and dental calculus revealed that Streptococcus mutans and Lactobacillus species are abundant in the oral microbiota associated with caries whereas their presence is less reported in dental calculus. However, the three pathogens known as the "red complex", namely Porphyromonas, Tannarella and Treponema, which are associated with the development of periodontal pathology, are strongly present in the dental calculus microbiome.

Conclusion: The microbiota composition associated with dental caries and calculus highlights specific microbial signatures for each of the two oral pathologies, underscoring their differences and microbiological complexity, while the possible relationship between the formation of dental calculus and the development of caries remains unclear.

Objective: This study aims to identify miRNA-mediated regulation of the cell cycle in oral tongue cancer.

Methods: Comprehensive computational analysis was performed on the GEO dataset "GSE168227". DIANA Tool-mir path v.3, STRING, Cytoscape 3.6.0, Enrichr, and TargetScan Human 7.2 were utilized to identify and analyze miRNAs and their targets in oral tongue cancer. The identified miRNA and its target genes were further analyzed in oral tongue cancer patients using qPCR and immunohistochemistry (IHC).

Results: Computational analysis revealed miR-17 as a differentially expressed miRNA in oral tongue cancer. Database analysis indicated potential binding sites of miR-17 for CDKN1A and CCND1 mRNA at 3'-UTR. In oral tongue cancer samples, miR-17, CDKN1A, and CCND1expression were upregulated compared to controls. IHC demonstrated overexpression of p21 and Cyclin D1 across various tumor grades, with predominant cytoplasmic expression of p21 observed in oral tongue cancer samples.

Conclusion: The findings suggest that miR-17 may regulate the G1-S transition of the cell cycle in oral tongue cancer. Further validation and functional studies are warranted to confirm their role as biomarkers.

Objectives: This study aims to evaluate the genetic association between emotional disorders and TMD-related pain through two-sample Mendelian randomization analysis.

Design: Single-nucleotide polymorphisms (SNPs) related to emotional disorders (worry, nerves, or depression) were selected from genome-wide association studies (GWAS) from UK Biobank consortia, and related these to SNPs from FinnGen consortia. The inverse-variance weighted (IVW) was used as the primary effect estimate between emotional disorders and TMD-related pain, and various methods were applied to test the reliability and stability of the results, namely MR-Egger and weighted median.

Results: The Mendelian randomization analysis showed that there was a positive correlation between emotional disorders and TMD-related pain, including worry group (IVW odds ratio (OR) = 3.86, 95 % confidence interval (CI) = 1.67-8.91), nerves group (IVW OR = 11.20, 95 % CI=2.04-61.64) and depression group (IVW OR = 3.32, 95 % CI=1.24-8.90). MR-Egger intercept and MR-PRESSO global test did not suggest evidence of horizontal or directional pleiotropy. Cochran's Q test showed that there was no heterogeneity between instrumental variables.

Conclusions: This study provides genetic evidence that strengthens the connection between emotional disorders and TMD-related pain, which has important implications at the causal level as well as throughout the treatment process of TMD-related pain.

Objective: This proof-of-concept sequence of in vivo/in vitro studies aimed to unveil the role of acquired enamel pellicle (AEP) engineering with statherin-derived peptide (StN15) on the AEP protein profile, enamel biofilm microbiome in vivo and on enamel demineralization in vitro.

Design: In vivo studies, 10 volunteers, in 2 independent experiments (2 days each), rinsed (10 mL,1 min) with: deionized water (negative control) or 1.88 × 10^-5 M StN15. The AEP, formed along 2 h and the biofilm, along 3 h, were collected. AEP was analyzed by quantitative shotgun-label-free proteomics. The enamel biofilm microbiome was evaluated using 16S-rRNA Next Generation Sequencing (NGS). An in vitro model with microcosm biofilm was employed. Bovine enamel samples (n = 72) were treated with 1) Phosphate-Buffer-Solution (PBS), 2) 0.12 %Chlorhexidine, 3) 500ppmNaF; 4) 1.88 × 10^-5MStN15; 5) 3.76 × 10^-5MStN15 and 6) 7.52 × 10^-5MStN15. Biofilm was supplemented with human saliva and McBain saliva and cultivated for 5 days. Resazurin, colony forming units (CFU) and Transversal Microradiography Analysis-(TMR) were performed.

Results: Proteomic results showed several proteins with acid-resistant, calcium-binding, and antimicrobial properties in the StN15 group. The microbiome corroborated these findings, reducing bacteria that are closely related to dental caries in the StN15 group, compared to the PBS. The microcosm biofilm showed that the lowest concentration of StN15 was the most efficient in reducing bacterial activity, CFU and enamel demineralization compared to PBS.

Conclusion: StN15 can effectively alter the AEP proteome to inhibit initial bacterial colonization, thereby mitigating enamel demineralization. Future research should explore clinical applications and elucidate the mechanisms underlying the protective effects of StN15.

Objective: To evaluate the antimicrobial capacity and cell viability of a final irrigation protocol based on the use of a hydrolases enzymes mixture (HEM) and a hyperosmotic solution (HS) as an alternative to conventional protocols.

Methods: Root canals from 28 human first molars were used to develop multispecies anaerobic biofilms in standard reactors and irrigated with various protocols according to the following groups. Group A: control (sterile saline), group B: 2.25 % NaOCl, group C: 1 % NaOCl, group D: HS, group E: 100 U/mL HEM + 1 % NaOCl, group F: 100 U/mL HEM + HS, or group G: 100 U/mL HEM. The disinfection evaluation per group was carried out by CFU counting and Scanning Electron Microscopy (SEM). The viability was determined on fibroblasts.

Results: The F group, which consisted in irrigating with HEM + HS, had a biofilm elimination of over 5.33 (Log reduction), as well as the groups treated with NaOCl with eliminations of up to 5.34 (Log reduction). In addition, the evaluation of viability reflects a biocompatibility of the F group treatment, as opposed to the groups treated with NaOCl.

Conclusions: The irrigation protocols with HEM+HS and HEM+NaOCl turned out to be as efficient as the conventional protocol using NaOCl; moreover, the irrigation protocol with HEM+HS had low cell cytotoxicity in the viability assay when compared to cell cultures exposed to NaOCl.

Clinical significance: It is imperative that new and innovative ways are found for root canal therapy to ensure that the root canal system can be thoroughly cleaned.

Objective: We assessed levels of mRNA encoding two glucocorticoid receptor (GR) isoforms (GRα and GRβ) in saliva and examined their relationship with hair cortisol levels and dental caries experience.

Design: Adolescents and young adults were assessed for dental caries experience, and hair cortisol was measured by ELISA. RNA was extracted from whole saliva using TRIzol, followed by quantitative real-time PCR analysis of GRα, GRβ, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH).

Results: GRβ mRNA was not detectable in most samples, whereas GRα mRNA was observed in all samples. There were significantly lower levels of GRα mRNA in individuals with elevated hair cortisol levels than in those with normal cortisol levels. Levels of GRα mRNA did not differ significantly in individuals with dental caries experience compared to individuals with no caries experience.

Conclusions: We identified and quantified mRNA encoding GRα in saliva. Its levels were inversely associated with hair cortisol (a marker of chronic stress). Although caries experience was associated with hair cortisol levels, there was no significant association between GRα levels and caries experience. Chronic stress has been proposed to be associated with reduced expression of GRα and this association appears to hold for GRα mRNA levels in saliva.

Objective: This study aimed to compare the effects of a combination of sodium fluoride, soluble calcium, and pyrophosphate (FCaP) versus fluoride alone in inhibiting enamel caries progression.

Design: Different FCaP solutions were prepared, and two were selected for testing (FCaP-1: F = 76 mmol/L, Ca = 7.6 mmol/L, P = 7.6 mmol/L, FCaP-5: F = 76 mmol/L, Ca = 23 mmol/L, P = 23 mmol/L). Fluoride solution (F = 76 mmol/L) was used as a control. Fluoride and calcium bioavailability in the solutions were measured, and NMR analysis was used to identify fluorine-containing complexes. Sound bovine enamel samples (n = 24 / group) underwent a 4-day pH cycling protocol followed by an additional 3 days of demineralization. Micro-hardness testing and fluoride concentration measurements were performed.

Results: FCaP-1 and FCaP-5 demonstrated nearly 100 % fluoride and calcium bioavailability. NMR analysis confirmed the formation of fluorine-containing complex. Enamel treated with FCaP-5 exhibited significantly less reduction in subsurface hardness after pH cycling and additional demineralization compared to fluoride alone. Interestingly, fluoride concentration and acid resistance on enamel surfaces treated with FCaP-5 was lower than with fluoride alone (Steel's multiple comparison test, p < 0.05).

Conclusions: FCaP effectively inhibits caries progression in subsurface enamel layers under pH cycling conditions by providing bioavailable calcium, indicating that FCaP increases the effectiveness of fluoride in caries management. FCaP may be a valuable addition to clinical practice, particularly for improving the effectiveness of fluoride-containing oral care products in individuals with low salivary calcium levels.

Objective: This review aims to provide an overview of the role of microorganisms in the onset and progression of periapical diseases, particularly regarding their effects on bone homeostasis.

Design: The search for this narrative review was conducted in PubMed, Web of Science and Google Scholar using relevant keywords, including checking reference lists of journal articles by hand searching.

Results: Microorganisms directly promote osteoclasts through pathways such as nuclear factor-κB (NF-κB) and extracellular regulated protein kinases (ERK), while inhibiting osteoblasts function by interfering with the wingless-related integration site (Wnt)/β-catenin pathway in the periapical area. Moreover, microorganisms indirectly regulate periapical bone homeostasis by inducing programmed cell death and modulating the immune microenvironment through the activation of innate immunity via pattern-recognition receptors (PRRs) and subsequent cascades of responses. Among these microorganisms, Enterococcus faecalis, Porphyromonas gingivalis and Fusobacterium nucleatum play significant roles.

Conclusion: Microorganisms regulate pathways such as NF-ĸB and Wnt/β-catenin, as well as programmed cell death and the immune microenvironment in the periapical area, thereby disrupting bone homeostasis.