Focus and Scope JAOS’s mission is to disseminate scientific and technological advances made by the dental and speech and hearing communities, respecting quality indicators in order to ensure their acceptability to researchers in the field. Its main objective is to publish the results of original research in the field of oral sciences, with an emphasis on dentistry, speech therapy and related areas. Submissions of case reports (including case series and clinical protocols) and short communications are not accepted by JAOS and review manuscripts (including systematic reviews) can only be sent at the invitation of the editor.
Universidade de São Paulo. Faculdade de Odontologia de Bauru
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Molecular alterations in MAPK/ERK, β-Catenin/Wnt, and PI3K/mTOR pathways in adenomatoid odontogenic tumor
Background Previous studies have suggested that tumorigenesis of adenomatoid odontogenic tumor (AOT) may involve the activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway. However, research on other oncogenic signaling pathways in AOT remains limited. Objective This study aimed to investigate gene mutations (Kirsten rat sarcoma viral oncogene homolog (KRAS), catenin beta 1 (CTNNB1), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA)) and their associated protein expressions (phosphorylated extracellular signal-regulated kinase 1 and 2 (p-ERK1/2), β-catenin, and phosphorylated mechanistic target of rapamycin (p-mTOR)) in AOT cases. The association between gene mutations and protein expression was also examined. Methodology In total, eight formalin-fixed, paraffin-embedded AOT tissue samples were manually micro-dissected for DNA extraction. Polymerase chain reaction was performed. Positive samples underwent DNA sequencing. Mutations were analyzed in KRAS exon 2 (codons 12 and 13), CTNNB1 exon 3 (codons 32-45), and PIK3CA exon 9 (codons 542-549). Protein expression was assessed using immunohistochemistry. Results KRAS mutations (specifically G12R and G12V) were detected in three of the eight cases (37.5%). CTNNB1 mutation (T42I) was identified in one of six cases (16.7%), whereas no PIK3CA mutation was observed. Moreover, moderate expression of p-ERK1/2 and p-mTOR were found in tumor cells of AOT. β-catenin accumulation was detected in seven cases (87.5%), predominantly showing membranous and cytoplasmic localization with no nuclear β-catenin expression. Statistical analysis indicated no association between gene mutations and protein expression. Conclusions KRAS mutations and p-ERK1/2 expression support a potential role of MAPK/ERK signaling in AOT pathogenesis. The absence of PIK3CA mutations despite p-mTOR expression may in part suggest mutation-independent activation of the PI3K/mTOR pathway. The lack of nuclear β-catenin accumulation may suggest that canonical Wnt signaling is less likely to significantly contribute to AOT tumorigenesis. Further studies with larger cohorts and investigations of additional molecules related to these pathways are warranted.
Copyright (c) 2026 https://creativecommons.org/licenses/by/4.0
Time-series trends and regional disparities in complete denture production in Brazil (2000–2023)
Introduction Tooth loss remains a public health problem in Brazil, reflecting social inequality, population aging, and limited access to oral rehabilitation. For many individuals, complete dentures (CD) are the only option available free of charge through the Brazilian Unified Health System (Sistema Único de Saúde, SUS). However, nationwide assessments of service delivery and regional equity in prosthetic rehabilitation are limited. Objective To quantify national trends and regional disparities in CD production within the SUS and examine how prosthetic output relates to demographic, socioeconomic, and infrastructure indicators using the most recent data available. Methodology This ecological-analytical time-series study used open data from the SUS Outpatient Information System (SIA/SUS). The analysis included maxillary and mandibular CD procedures recorded between 2000 and 2022, representing the most recent consolidated period for temporal modeling, and a state-level snapshot for 2023 to describe the latest correlational scenario. Production rates were standardized per 100,000 inhabitants. Temporal trends were analyzed using segmented linear regression to estimate the average annual percent change (AAPC), which summarizes overall long-term changes in complete denture production, and to identify inflection points. Correlations between CD production and demographic or socioeconomic indicators were tested using Spearman’s rho (α = 0.05). Results Between 2000 and 2022, a total of 5,239,089 complete dentures were delivered through the Brazilian Unified Health System. CD production increased significantly nationwide from 2000 to 2022 (AAPC = 9.7%; 95% CI: 4.8–14.9), a relatively high annual growth rate for public health service expansion, with the steepest rise between 2006 and 2014 (AAPC = 29.2%; 95% CI: 18.6–40.7). Regional trends varied across the country, with the highest growth observed in the Northeast (AAPC = 16.4%; 95% CI: 11.7–21.3), followed by the North (AAPC = 14.3%; 95% CI: 10.9–17.7), Central-West (AAPC = 13.4%; 95% CI: 4.9–22.5), and South (AAPC = 12.8%; 95% CI: 9.0–16.7), whereas the Southeast showed the smallest expansion (AAPC = 8.0%; 95% CI: −1.7–18.8). In 2023, the SUS network included 2,903 prosthetic laboratories, highlighting the organizational infrastructure supporting prosthetic rehabilitation services. In 2023, São Paulo (Southeast region) produced 111,396 dentures, and Piauí (Northeast region) recorded the highest production rate (833.36 per 100,000 inhabitants). Strong correlations were observed between CD production and population size (ρ = 0.742, p < 0.001) and number of municipalities (ρ = 0.938, p < 0.001). Conclusion Over the past two decades, complete denture production within the SUS expanded substantially, reflecting the consolidation of Brazil’s public oral health policies. However, persistent regional disparities and heterogeneous production rates indicate that service expansion has not translated into equitable coverage nationwide. These findings highlight the importance of demographic and organizational factors in shaping prosthetic service provision and underscore the need for targeted planning and resource allocation to reduce inequalities in access to oral rehabilitation.
Expression of p53, Ki-67, sox-2, oct-4, and NANOG in the tongue and trachea of Swiss mice exposed to narghile smoke
Introduction: Narghile (waterpipe) tobacco use has increased worldwide, partly due to limited awareness of its harmful effects. Despite the widespread misconception that the water filters toxic substances, the chemical composition of narghile smoke is comparable to that of cigarette smoke. However, its effects on airway tissues remain poorly understood. Objective: This study aimed to evaluate the histological and immunohistochemical profiles of the tongue and trachea in Swiss mice exposed to narghile smoke. Methodology: Sixty animals were divided into six groups: a control group (0 days) and experimental groups exposed daily to narghile smoke for seven, 15, 30, 60, and 90 days. After euthanasia, tongue and tracheal tissues were collected for histological (hematoxylin and eosin staining) and immunohistochemical analyses of NANOG, OCT-4, SOX-2 (neoplastic stem cell markers), Ki-67, and p53 in epithelial cells. Results: Histological evaluation revealed cytological and architectural alterations in the tongue, suggestive of early dysplastic changes. In the trachea, early metaplastic modifications were observed, including cilia loss, epithelial hyperplasia, and mild keratinization. These changes increased with longer exposure duration. Immunohistochemical analysis showed greater expression of NANOG, OCT-4, SOX-2, and p53, peaking at 30 days, whereas Ki-67 expression peaked at 90 days. Elevated p53 levels suggest alterations in cell cycle regulation and apoptosis. Conclusion: Narghile smoke induced histological and molecular changes in the tongue and tracheal epithelium of mice, indicating a potential carcinogenic effect. Further in vitro, in vivo, and clinical investigations are warranted to validate these biomarkers and better elucidate the biological effects of narghile smoke exposure.
Copyright (c) 2026 Sarah Freygang Mendes Pilati, Filipe Ivan Daniel, Paulo Vinicius Fontanella Pilati, Mariana Hornung Marins, Aline Cristina Batista Rodrigues, Filipe Modolo https://creativecommons.org/licenses/by/4.0
Modulation of TLR4, hBD-2, and hBD-3 expression and hepatic tissue response by systemic probiotics in experimental apical periodontitis in rats
Apical periodontitis is characterized by a robust inflammatory response and activation of innate immunity. Probiotics have been proposed as modulators of this response, but their local and systemic effects remain unclear. Objective To evaluate whether systemic supplementation with L. rhamnosus LR-04 and L. acidophilus LA-14 modulates the expression of TLR4, hBD-2, and hBD-3 in a rat model of experimental apical periodontitis (AP), and to assess potential histopathological alterations in the liver. Methodology Twenty-four male Wistar rats were randomly allocated into three groups (n=8): control (AP + water), AP + L. rhamnosus LR-04, and AP + L. acidophilus LA-14. AP was induced by exposing the pulp chambers of the first mandibular molars for 30 days. From the day of induction, probiotics (109 CFU/day via oral gavage) or water (control) were administered daily. After 30 days, the rats were euthanized. Mandibles were processed for immunohistochemical analysis of hBD-2, hBD-3, and TLR4 expression, which was assessed semi-quantitatively. Liver samples were collected, fixed, and stained with hematoxylin-eosin for histopathological evaluation of lobular inflammation, necrosis, portal inflammation, and fibrosis. Data were analyzed using the nonparametric Kruskal–Wallis test at a 5% significance level. Results No hepatic histopathological alterations were observed in any group. Probiotic supplementation resulted in significantly greater hBD-2 immunoreactivity in periapical tissues compared to the control group (P<0.05). hBD-3 expression was significantly higher in the L. acidophilus LA-14 group than in both the control and L. rhamnosus LR-04 groups (P<0.05). TLR4 expression in periapical lesions was increased in both probiotic groups relative to control (P<0.05). Conclusion Systemic supplementation with L. rhamnosus LR-04 and L. acidophilus LA-14 enhanced the local immune response in apical periodontitis, as evidenced by upregulation of TLR4, hBD-2, and hBD-3, without inducing detectable hepatic histopathological alterations.
Gabrielle Cabral Melville de Souza Tenório
Systemic toxicity assessment of tissue conditioners modified with nystatin and chlorhexidine in a rat model of denture stomatitis
Denture stomatitis is a condition that commonly affects the palatal mucosa of denture wearers. Recently, several treatments have shown promising results, including the addition of antimicrobial drugs to tissue conditioners. However, before initiating clinical trials, the safety profile of this modified material must be assessed. Objective This study investigated the potential systemic toxicity of a tissue conditioner modified with antifungals in a rat model of denture stomatitis. Methodology Male Wistar rats (N=59) were randomly assigned to the following groups: NC (negative control), SD (sterile device), DS (denture stomatitis), Soft (Softone), Nys (nystatin), Nys:βCD (nystatin:β-cyclodextrin), Chx (chlorhexidine), and Chx:βCD (chlorhexidine:β-cyclodextrin). Animals of all groups, except for NC and SD, wore a palatal device contaminated with Candida albicans for the induction of denture stomatitis. Rats from the Soft group had their devices relined with a tissue conditioner (Softone) with no drugs added, while devices from groups Nys, Nys:βCD, Chx, and Chx:βCD were relined with antifungals at their minimum inhibitory concentrations against C. albicans SC5314 (32 mg, 36 mg, 64 mg, and 46 mg for each gram of tissue conditioner, respectively). Four days after treatment, the animals had their blood collected for biochemical analyses and had their livers, lungs, stomachs, and kidneys removed for histopathological and enzymatic analyses. Results No significant renal, gastric, or pulmonary changes were detected. Some rats from groups Nys, Nys:βCD, Chx, and Chx:βCD presented vacuolation of hepatocytes, although this is not necessarily a sign of hepatic damage. However, the livers of the Chx group presented higher myeloperoxidase activity when compared to the NC, SD, and DS groups. Conclusion These findings suggest that incorporating Nys, Nys:βCD, and Chx:βCD into this tissue conditioner may represent a safe option for denture stomatitis treatment.
Salivary cotinine and S100A8/A9 levels in children exposed to environmental tobacco smoke
Exposure to environmental tobacco smoke (ETS) poses significant risks to children’s oral health by inducing oxidative stress and triggering inflammatory responses. Even in the absence of clinically evident oral inflammation, early biological changes can be detected in children exposed to ETS. Objectives This study aimed to evaluate salivary cotinine and S100A8/A9 levels in children exposed to ETS and to examine the relationship between exposure intensity and inflammatory biomarker expression. Methodology This observational case-control study included 150 systemically healthy children aged 6–12 years. ETS exposure was determined using parent-reported questionnaires. Clinical parameters, including plaque index, gingival index, and probing pocket depth, were recorded. Unstimulated saliva samples were analyzed for cotinine, S100A8, and S100A9 using ELISA kits. Group comparisons were conducted using the Mann–Whitney U test, and correlations were assessed using Spearman’s rank correlation coefficient. Statistical significance was set at p<0.05. Results ETS-exposed and non-exposed groups did not differ significantly in age, sex, socioeconomic status, oral hygiene habits, or clinical periodontal parameters (p>0.05). However, salivary cotinine, S100A8, and S100A9 levels were significantly higher in ETS-exposed children (p<0.05). Cotinine demonstrated a moderate positive correlation with S100A8, while its correlation with S100A9 was weak and non-significant. Exposure intensity was positively associated with cotinine and S100A8 levels, but not with S100A9. Conclusion ETS exposure in children is associated with early biochemical signs of inflammation, even in the absence of clinically detectable periodontal changes. Elevated salivary cotinine and S100A8 levels highlight the potential utility of salivary biomarkers for identifying subclinical effects of passive smoking. These findings underscore the importance of interventions aimed at reducing children’s exposure to ETS to protect long-term oral health. Clinical trial registration: NCT06791707
Polyphenol-functionalized silver nanoparticles promote differential remineralization and reinforcement of demineralized dentin
Silver nanoparticles (AgNPs) have gained relevance in restorative dentistry due to their antimicrobial and remineralizing properties. However, the role of AgNPs functionalized with different polyphenols in dentin remineralization remains insufficiently understood. Objectives This study aimed to synthesize and characterize AgNPs functionalized with crosslinking polyphenols extracted from grape seed extract (GSE) and green tea leaves (GT), and to evaluate their biocompatibility and their effects on the mechanical and physicochemical properties of demineralized dentin. Methodology AgNPs were characterized by TEM, XRD, TGA, and zeta potential analysis to determine particle morphology, crystalline structure, chemical composition, and surface charge. Biocompatibility was assessed using fibroblast cytotoxicity assays. In total, 40 human mid-coronal dentin specimens were randomly assigned to four groups (n=10): Control- (sound dentin), Control+ (pH-cycled dentin without treatment), AgGSE (pH-cycled + AgGSE, 1 min), and AgGT (pH-cycled + AgGT, 1 min). Treated dentin was analyzed by ATR-FTIR, XRD, TGA, and three-point bending tests. Results Both AgNPs were successfully synthesized and exhibited high biocompatibility. AgGSE demonstrated greater dentin matrix interaction, resulting in significantly higher flexural strength (p≤0.001). In contrast, AgGT induced pronounced remineralization with increased PO4/Amide I ratio (p=0.003) and CO3/PO4 ratios (p=0.007 by TGA; p=0.03 by ATR-FTIR), consistent with carbonated apatite deposition. Conclusions Green-synthesized AgNPs functionalized with GT or GSE promoted reinforcement and remineralization of demineralized dentin through distinct mechanisms of action. These findings highlight their potential as biocompatible agents for dental therapies.
Statin-loaded carbonated hydroxyapatite nanoemulsion controls matrix metalloproteinase-1 activity to enhance post-orthodontic stability in rats
Background The persistence of periodontal ligament (PDL) and alveolar bone remodeling following appliance removal is a key factor in orthodontic relapse, which is a significant barrier to treatment stability. In this study, a statin-loaded carbonated hydroxyapatite (CHA) nanoemulsion was evaluated as a local therapy to control relapse rate by modulating matrix metalloproteinase-1 (MMP-1) in rats. Methodology A total of 48 rats (n=48) were allocated to control, simvastatin, CHA hydrogel, or CHA–simvastatin nanoemulsion groups. Treatments were delivered intrasulcularly during stabilization, and relapse was measured at days zero, one, seven, and 14 post-debonding. MMP-1 expression in the PDL was assessed using immunofluorescence at the same time points. Collected data were evaluated using analysis of variance. Results Relapse occurred in all groups, with the highest relapse rate during early observation. At day one, the relapse rate was significantly reduced in treatment groups compared with the control, and the CHA–simvastatin group showed the lowest relapse rate (control 1048±20.20 vs. CHA–simvastatin 549.33±27.22 μmd−1; p=0.001). MMP-1 expression peaked at day one and was significantly lower in all treatment groups than control, with the greatest suppression in the CHA–simvastatin group (16.33±2.08 vs. 7.33±0.57 positive cells/field; p=0.001). By day 14, relapse rates and MMP-1 expression decreased across groups, with persisting advantages for the combined treatment. Conclusion Local CHA-simvastatin nanoemulsion decreased early relapse and downregulated MMP-1 expression in rats, suggesting a promising adjunctive strategy to enhance post-orthodontic stability.
Comparison of root coverage by injectable-platelet rich fibrin in thick and thin phenotypes
Objective This study aimed to compare the effectiveness of injectable platelet-rich fibrin (I-PRF) using a submucosal injection technique for creeping attachment in thin and thick phenotypes with gingival recession. Methodology The study was designed as a prospective clinical trial. Participants were divided into two groups based on gingival thickness (GT): thin phenotype group (≤1.0 mm) and thick phenotype group (>1.0 mm). I-PRF was applied once a month to each gingival site using the submucosal injection technique, for a total of three applications. Periodontal parameters were measured at baseline (T0), nine months after treatment (T1), and 12–48 months after treatment (T2). Root coverage percentage (RC%) was calculated. Results Twelve systemically healthy, non-smoking patients (seven males and five females; mean age: 36.5±9.4), comprising 66 teeth, were analyzed. The primary outcome, RC%, demonstrated a statistically significant intergroup difference at T1 (p=0.032); however, this difference was not statistically significant at T2. In the thick phenotype group, RC% was 20.91±30.80% in T1 and increased to 31.40±30.92% in T2 (p=0.040). Conversely, the thin phenotype group showed higher RC% values at T1 (35.04±29.76%), which were not sustained at T2 (30.70±28.46%; p=0.355). Recession depth decreased in both groups at all time points, but this difference was not statistically significant. Keratinized tissue width showed a significant increase in both groups, from 2.34±1.08 and 2.73±0.95 at T0, respectively, to 2.89±1.17 and 3.28±1.12 at T1 (p<0.05). In the intergroup comparison, GT values were significantly higher in the thick phenotype group than in the thin phenotype group at T0 and T2, while no significant difference was observed at T1. Conclusion I-PRF application was shown to enhance RC% in both phenotypes. A significant increase in GT was observed in the thin phenotype; however, these increases in GT and RC% were not fully sustained during long-term follow-up in this sample.Clinical Trial registration: NCT05591326
Influence of impacted mandibular third molars on pathological changes on themselves and adjacent tissues across different age groups
Objective To investigate the effects of different types of impacted mandibular third molar (IMTM) on lesions in situ and on adjacent tissues at different ages. Methodology Cone Beam Computed Tomography (CBCT) images of 1007 IMTM cases were retrospectively analyzed. Associations between age, gender, impaction type, distal alveolar bone condition of mandibular second molar (MSM), IMTM-MSM contact status and occurrence of lesions on IMTM and its adjacent tissues were evaluated using Pearson’s chi-squared test and Fisher’s exact test. Results MSM distal alveolar bone defects showed the highest incidence among all IMTM-related lesions (79.2%), followed by MSM distal external root resorption (ERR) (25.5%) and MSM distal caries (10.4%). Mesioangular (96.2%, p<0.001) and horizontal (95.9%, p<0.001) IMTM were associated with more severe bone defects and the incidence increased with age. IMTM-MSM surface-to-surface contact was significantly associated with MSM distal caries severity (12.5%, p<0.001) and distal ERR (29.5%, p<0.001). Inflammatory resorption of MSM distal alveolar bone was significantly correlated with MSM distal caries (47.1%, p<0.001), ERR (36.5%, p<0.05), distal alveolar bone defects (100%, p<0.001), and IMTM caries (14.1%, p<0.05). Study design followed the STROBE guidelines. Conclusion Mesioangular impaction, horizontal impaction, MSM-IMTM surface-to-surface contact, and MSM distal alveolar bone in a state of inflammatory resorption greatly affect lesions on IMTM and its surrounding tissues. These findings suggest the prophylactic extraction in young adults (18–25 years) with high-risk impactions, while recommending observation or cautious management for asymptomatic older patients without signs of inflammatory bone resorption.
Expression of caspase-8 in non-alcoholic fatty liver disease related to ligature-induced periodontitis in rats
Aim This study aimed to evaluate the oral and hepatic changes, as well as the expression of caspase-8 in liver tissue damage, both associated with ligature-induced periodontitis in rats. Methodology A total of 16 female Wistar rats were divided into two groups (n=8): one received ligature around the first lower molar to promote periodontitis, and the other was the control group with no ligature. After the period of induction of the disease the animals were evaluated by clinical measures for periodontitis, euthanized, and the samples of gingival tissue, hepatic tissue, and serum were collected to the measurement of biomarkers for inflammation (myeloperoxidase), oxidative stress (glutathione, malonaldehyde, and nitrate [NO3]), liver damage and histopathological evaluation with immunohistochemistry for caspase-8. The data were expressed as mean and standard deviation for data with normal distribution or median and interquartile range for data with non-normal distribution. We used ANOVA followed by the Student-Newman-Keuls test for multiple comparisons of normally distributed data, and the Kruskal-Wallis test followed by Dunn's test for non-normally distributed data. The statistical tests were performed with GraphPad Prism Software (version 5.0), in which a p-value <0.05 was considered significant. Results Our study demonstrates that the group with ligature-induced periodontitis showed increased measurement of periodontal destruction, local and systemic biomarkers of inflammation as well as liver damage which we observed several hepatocytes with loss of conformation and steatosis in the periodontitis group. The histopathological evaluation evidenced the periodontitis-related steatosis and higher expression of Caspase-8 in comparison with the control group (p<0.0006). Conclusion Our study demonstrates the high expression of Caspase-8 in liver damage related to ligature-induced periodontitis in rats.
Any Carolina Cardoso Guimarães Vasconcelos
Can angiotensin II affect the inflammatory response of human dental pulp cells in vitro?
Dental pulp fibroblasts respond to various stimuli, including microbial agents, endodontic materials, restorative procedures, pulp protection treatments, and inflammatory molecules. Its inflammatory response to injury involves a complex set of mechanisms that have been increasingly studied for their roles in this intricate biological process. Among these mechanisms is angiotensin II (ANG-II), the involvement of which in inflammation has been shown in several pathological conditions via its local generation and action. Objective This study aimed to evaluate the capacity of fibroblasts from permanent and deciduous dental pulp to express inflammatory mediators when exposed to bacterial and inflammatory antigens. It also sought to assess the presence of components of the renin-angiotensin system (RAS) and the potential modulatory role of ANG-II in this response. Methodology Fibroblasts were cultured from the pulp of permanent and deciduous teeth obtained from three adult and four pediatric donors with informed consent. Cells were stimulated with Porphyromonas gingivalis and Escherichia coli lipopolysaccharides (LPS) either alone or in combination with ANG-II and, in some cases, with IL-1β. Gene expression of RAS components and various inflammatory mediators was analyzed by qRT-PCR. ANG-II receptor expression was quantified by flow cytometry. Results The results showed that both bacterial antigens and IL-1β significantly upregulated the expression of genes encoding key inflammatory mediators. However, ANG-II, either alone or in combination with other antigens, failed to alter the expression levels of these mediators. Conclusion These findings clearly show that ANG-II has no influence on the expression of inflammatory mediators by human dental pulp fibroblasts under the tested conditions.
Clinical and aesthetic outcomes of enamel matrix derivative and subepithelial connective tissue graft using the modified coronally advanced tunnel technique
Objectives This randomized controlled clinical trial evaluated the short-term clinical outcomes of the modified coronally advanced tunnel technique combined with three different regenerative approaches—subepithelial connective tissue graft (as the gold standard), enamel matrix derivative (as a donor-site-sparing alternative), and their combination (to explore potential synergistic effects)—in treating recession type 1 gingival defects. Methodology A total of 52 systemically healthy patients (aged 18–60) with 90 recession type 1 gingival defects were enrolled and randomly assigned to one of the three treatment groups: Group 1 (n=18; subepithelial connective tissue graft), Group 2 (n=19; enamel matrix derivative), and Group 3 (n=15; both materials). Primary outcome consisted of the percentage of root coverage at 6 months. Secondary outcomes included plaque index, gingival index, gingival recession depth, gingival recession width, clinical attachment level, keratinized tissue width, gingival thickness, wound healing index, probing depth, and root coverage aesthetic score. Clinical parameters were measured at baseline, 3, and 6 months, and aesthetic outcomes were assessed at 6 months. Results All groups showed significant improvements in clinical parameters. Mean root coverage was 80.4% for Group 1, 76.2% for Group 2, and 73.6% for Group 3, with no significant differences among them. Keratinized tissue width significantly increased in Group 1 and Group 3, but not in Group 2. Mean root coverage aesthetic score values were 7.74 ± 2.35, 7.54 ± 2.39, and 7.62 ± 1.97, respectively (p > 0.05). Conclusion Within the limitations of this study, including its short-term follow-up period and baseline differences in recession width, all three groups exhibited comparable clinical and aesthetic outcomes at 6 months. Clinical Trial Registration Number: NCT06504329
Parkinson's disease and Porphyromonas gingivalis levels
Neurodegenerative diseases have been associated with periodontal diseases. Objectives This study aimed to evaluate the clinical and epidemiological aspects of the association between Parkinson's disease (PKD) and periodontitis (PE), including the quantification of Porphyromonas gingivalis and the influence of different risk variables on this association. Methodology This case-control study included 172 individuals: 86 cases (PKD) and 86 controls (without any neurodegenerative disease). Participants underwent a complete periodontal examination (plaque index and probing depth), and clinical subgingival sampling was conducted to quantify Porphyromonas gingivalis counts. The association between PKD and PE was evaluated through univariate and binary logistic regression analyses. Results A high prevalence of PE (73.2%) was observed among individuals with PKD [OR=3.99 (2.00-7.59); p<0.001]. Variables that were significantly retained in the final binary logistic regression model for the occurrence of PKD were: PE (OR=3.23; p=0.003), mean P. gingivalis counts (OR= 3.39; p=0.036), lower number of teeth (OR= 2.21, p<0.001), low frequency of toothbrushing/day (OR=1.95; p=0.006), and bleeding on probing (OR=2.45; p<0.001). The significant positive correlations observed between P. gingivalis counts and clinical periodontal parameters were considered moderate to strong in individuals with PKD. Conclusions A strong association between PKD and PE was demonstrated, with risk increasing in parallel with the severity of periodontal involvement. Furthermore, individuals with PKD exhibited significantly higher levels of P. gingivalis compared to controls.
Objective. Despite emerging evidence pointing to a comorbidity between temporomandibular disorders (TMD), bruxism, and neuropsychiatric conditions such as Attention-Deficit/Hyperactivity Disorder (ADHD), limited studies have explored this relationship in adult populations. This study aimed to investigate the prevalence of painful TMD and self-reported bruxism in adults with highly consistent ADHD symptoms. Methodology. In total, 90 adult participants were divided into two groups based on the Adult ADHD Self-Report Scale Screener, G1: individuals with highly consistent ADHD symptomatology (n=60), and G2: controls (n=30). All participants completed validated instruments assessing TMD (TMD Pain Screener), self-reported bruxism (OBC), anxiety (GAD-7), somatization (PHQ-15), perceived stress (PSS), sleep quality (PSQI), pain hypervigilance (PVAQ), and jaw function (JFLS-8). The chi-square test, adjusted using Bonferroni criteria for multiple comparisons, and the Mann-Whitney U-test were used. Results. A higher prevalence of women (p=0.006), South Americans (p=0.008), and individuals with low/lower middle income (p=0.0001) was found in G1. G1 showed a significantly higher prevalence of painful TMD (p=0.001) and awake bruxism (p=0.013) compared to G2. Participants in G1 also exhibited significantly higher levels of anxiety, somatization, stress, poor sleep quality, pain hypervigilance, and jaw limitation (p<0.05). No significant differences in sleep bruxism were found between groups (p>0.05). Conclusion. These findings suggest a potential behavioral and emotional vulnerability to orofacial disorders in adults with highly consistent ADHD symptoms.
Attention deficit disorder with hyperactivity
Apical delta filling with calcium silicate and epoxy resin sealers using different obturation techniques by microcomputed tomography
Objectives This study aimed to evaluate the filling quality of simulated apical deltas in 3D-printed tooth replicas using microcomputed tomography and comparisons of two obturation techniques and calcium silicate cement-based sealer groups. Methodology A single-rooted, straight maxillary premolar was instrumented and scanned by microcomputed tomography to generate a 3D model. Apical delta configurations were digitally created and integrated into the canal anatomy. In total, 40 translucent resin replicas were 3D printed and randomly assigned for obturation with one of four sealer groups (AH Plus Resin, AH Plus Bioceramic, Bio-C Sealer, and NeoSealer Flo). Following obturation, all specimens were rescanned, and a volumetric analysis was performed to determine the percentage of the filled volume in the apical delta region. Statistical analyses included one-way ANOVA and the Kruskal-Wallis test (α=0.05). Results The continuous wave technique resulted in significantly greater apical delta filling than the single-cone one regardless of sealer. For the single-cone technique, NeoSealer Flo showed the highest filling percentage (42.7±2.0), followed by Bio-C Sealer (28.7±1.1), AH Plus Resin (24.9±1.9), and AH Plus Bioceramic (17.9±1.0). For the continuous wave technique, Bio-C Sealer showed the most filling (66.2±2.0), followed by NeoSealer Flo (54.2±1.4), AH Plus Resin (45.9±1.5) and AH Plus Bioceramic (36.8±1.0). Conclusions The continuous wave technique achieved the most apical filling, with Bio-C sealer showing the highest performance. Bio-C and NeoSealer Flo achieved significantly higher filling percentages than AH Plus Resin and AH Plus Bioceramic under the single-cone technique.
Effects of highly leukotoxic Aggregatibacter actinomycetemcomitans associated with ligature-induced periodontitis on oral and gut tissues in male rats
Objective To evaluate the effects of gastric administration of the highly leukotoxic Aggregatibacter actinomycetemcomitans JP2 strain (Aa JP2), with or without ligature-induced periodontitis, on periodontal and small intestinal tissues in a rat model. Methodology Forty-eight-week-old male Wistar rats were divided into four groups (n=10/group): Control (CG), Periodontitis (PG), Periodontitis and Aa JP2 (PAaG), and Aa JP2 only (AaG). Ligatures were placed in PG and PAaG on day one and maintained for 42 days. After six weeks of twice-weekly gastric Aa JP2 inoculation, mandibles and small intestines were analyzed using stereomicroscopy, micro-computed tomography (CT), and histopathology to assess alveolar bone loss, trabecular architecture, inflammatory infiltrate, vascular congestion, goblet cell density, and villus morphology. Statistical analyses included the Kruskal–Wallis, Mann–Whitney, and Chi-square tests for group comparisons (p<0.05), as well as Spearman’s correlation test. Results PG and PAaG exhibited significantly greater bone loss compared to CG and AaG (p<0.05). Micro-CT analysis revealed reduced trabecular thickness in AaG (342.4±23.1µm) compared to PG (378.2±28.1µm) and PAaG (385.5±45.1µm) (p<0.05). PAaG and AaG presented higher inflammatory infiltrate scores (>751 inflammatory cells) compared to CG and/or PG (p<0.05). Elevated vascular congestion and/or goblet cell hyperplasia in the jejunum and ileum were observed in PAaG and AaG compared to CG and PG (p<0.05). Villus height (duodenum/ileum) and villus width (jejunum/ileum) differed significantly among groups (p<0.0001). Significant correlations were identified: the alveolar bone volume/total volume ratio was positively associated with duodenal vascular congestion (rho=0.738; p=0.037); the periodontal inflammatory infiltrate was positively associated with jejunal goblet cell counts (rho=0.704; p=0.007); alveolar bone loss was positively associated with both duodenal and jejunal villus height (rho≥0.762; p<0.05); and bone volume was negatively associated with both jejunal vascular congestion (rho=-0.696; p=0.003) and jejunal goblet cell counts (rho=-0.617; p=0.011). Conclusions Gastric inoculation with Aa JP2 exacerbates ligature-induced periodontitis and independently induces intestinal morphological changes.
Effects of live and heat-killed Bifidobacterium lactis in rats with induced periodontitis
Background Probiotics and postbiotics have emerged as promising adjunctive therapies in managing periodontal disease. Bifidobacterium animalis subsp. lactis HN019 has shown antimicrobial and immunomodulatory effects in both experimental and clinical settings when administered orally. However, the systemic impact of this strain, independent of local oral effects, remains unclear. Objective To evaluate the systemic effects of live and heat-killed B. animalis subsp. lactis HN019 in a rat model of ligature-induced periodontitis, excluding direct contact with the oral cavity. Methodology A total of 32 Wistar rats were randomly assigned to four groups (n=8): control (C), periodontitis only (EP), periodontitis + probiotic (PRO), and periodontitis + postbiotic (POS). Periodontitis was induced by placing a cotton ligature around the cervical region of the lower right first molar, inserted into the gingival sulcus. Treatments were administered via oral gavage for 30 days before and 15 days after periodontitis induction. Alveolar bone loss and periodontal parameters were assessed using micro-computed tomography (microCT) and histomorphometric analysis. Results MicroCT revealed that ligature effectively induced periodontitis, reducing BV/TV and Tb.N and increasing Tb.Sp and Po.Tot. Probiotic and postbiotic treatments did not improve outcomes. Bone loss was lowest in the control group, with no differences between EP, PRO, and POS. Conclusion Systemic administration of Bifidobacterium animalis subsp. lactis HN019 or its derived postbiotic resulted in no significant improvements in periodontal outcomes in this experimental model. Further investigations using integrative approaches are needed to better characterize the systemic effects of probiotics and postbiotics.
Hydrogel microarchitecture as a regulatory cue for in vitro odontogenic differentiation
Objective This study introduces an innovative, cost-effective, and easily reproducible strategy for engineering three-dimensional bioprinted GelMA-based scaffolds, designed with ordered macroporous and tubular architectures, and integrated microfluidic channels to advance structural and functional performance. Their geometric features were specifically designed to investigate how microarchitectural cues influence the mineralizing cell differentiation of human dental pulp cells (HDPCs). Methodology The scaffolds were fabricated via an indirect bioprinting process using resin molds, resulting in cylindrical structures with distinct grid or honeycomb surface architectures. Biomaterials were characterized for morphology, surface topography, porosity, pore diameter, and degradability. Biological performance was evaluated by culturing HDPCs for 21 days to assess viability, proliferation, and mineralizing differentiation (ANOVA/Tukey; α=0.05). Results Both scaffold designs exhibited interconnected porous networks, with the honeycomb configuration presenting significantly larger pores. HDPCs cultured on the scaffolds showed high viability and proliferation, with the honeycomb architecture promoting elevated ALP activity. However, the grid architecture more effectively influenced odontoblastic differentiation and mineralized matrix deposition. Conclusion Our findings highlight the impact of biomaterial architecture on cellular behavior and reveal the potential of this novel bioprinting approach for bioactive dentin regeneration in dental tissue engineering.
The effect of Stage I-II periodontitis on the mechanical, structural, and biological properties of leukocyte and platelet-rich fibrin
Objective This study aimed to compare the mechanical, biological, and structural properties of a leukocyte- and platelet-rich fibrin (L-PRF) membrane in periodontally healthy patients and those with periodontitis. A total of 30 individuals (17 men and 13 women) with a median age of 41 years were divided into two groups as periodontally healthy (control group) and as having periodontitis (test group). Methodology Blood samples were collected and centrifuged at 2700 rpm for 12 minutes. A tensile test was performed to determine the mechanical properties of L-PRF membranes. Elasticity-modulus, tensile strength, and stretch at rupture were calculated. Platelet and leucocyte counts and ratios were calculated. Fibril thickness and density were evaluated by scanning electron microscopy imaging. The comparisons between groups were analyzed by the Mann–Whitney U test, and a p<0.05 value was considered statistically significant. Results In the comparison of the control group versus the test group, pocket depth (3.55 (1.59-3.97) vs. 1.52 (1.47-3.53)), clinical attachment level (3.11 (1.77-4.23) vs. 0.06 (0.05-3.68)), plaque index (1.63 (0.05-1.75) vs. 0.04 (0.04-1.58)), gingival index (1.55 (0.04-1.63) vs. 0.05 (0.04-1.49)), and bleeding on probing (56.25 (3.7-70.11) vs. 3.57 (2.67-47.12)) were statistically significantly higher in the test group than in the control group (p= 0.009, p=0.008, p=0.008, p=0.009, p=0.009, respectively). Elasticity-modulus, tensile strength, and stretch at rupture values showed no statistically significantly differences between groups (p=0.745, p=0.754, p=0.602, respectively). Fibril thickness and density values showed no statistically significant differences between groups (p=1.000, p=0.753, respectively). Platelet count and platelet and leukocyte ratio values showed no statistically significant differences between groups (p=0.754, p=0.600, p=0.142, respectively). Leukocyte count was found to be statistically significantly higher in the control group than in the test group (p=0.028). Conclusion This study showed no effect of Stage I-II periodontitis on the mechanical, structural, and biological properties of L-PRF. Further studies with larger sample sizes are required to confirm these findings.
Bond strength in class V cavities: an in vitro study on beveling, universal adhesive strategy, and composite type
Cervical Class V lesions present restorative challenges due to their multifactorial etiology and complex bonding substrates. Objectives: This study evaluated the influence of marginal bevel, bonding using a universal adhesive (etch-and-rinse or self-etch), and the resin composite type (conventional or bulk-fill) on the bond strength of simulated Class V cavities. Methodology: A total of 80 dental fragments (7mm×7 mm×2 mm) were obtained from bovine incisors. Cylindrical cavities with enamel margins and internal dentin walls were prepared centrally in each specimen. Samples were randomly assigned to groups based on three factors: presence or absence of bevel, bonding strategy (etch-and-rinse or self-etch), and resin composite type (conventional or bulk-fill). Groups with bevel received a 1 mm enamel bevel along the preparation margins using a conical diamond bur. Adhesive and restorative procedures were performed following the manufacturer’s recommendations. Bond strength was assessed using a push-out test on a universal testing machine. Data were analyzed using three-way ANOVA and Tukey’s post-hoc test (α=5%). Results: Presence of a marginal bevel did not significantly influence bond strength. The etch-and-rinse bonding strategy resulted in significantly higher bond strength than the self-etch approach, and bulk-fill composites presented superior performance compared with conventional composites. Conclusions: Combining a universal adhesive applied with the etch-and-rinse strategy and a bulk-fill composite proved to be an effective approach for enhancing bond strength with enamel and dentin substrates. Beveling of enamel margins did not improve the bond strength of Class V restorations, suggesting that this procedure may be unnecessary when margins are in enamel. Avoiding beveling in such situations contributes to preserve sound tooth structure and supports a more conservative restorative approach.
Comparative analysis of connective tissue graft versus ozone-enriched platelet-rich fibrin in the treatment of Cairo class I gingival recessions
Gingival recession is characterized by the apical displacement of the marginal gingiva, exposing the root surface and causing aesthetic and functional issues such as dentin hypersensitivity and cervical lesions. Subepithelial connective tissue grafts (SCTG) are considered the gold standard for root coverage. Recently, ozone-enriched advanced platelet-rich fibrin (A-PRF) has emerged as a promising alternative due to its regenerative potential and biocompatibility. Objectives: To compare the clinical efficacy of ozone-enriched A-PRF and SCTG combined with the coronally advanced flap (CAF) technique to treat Cairo Class I gingival recessions. Methodology: This randomized, double-blind, controlled clinical trial included 22 healthy patients (mean age 32.23±11.86 years, range 20–60 years), each with bilateral Cairo Class I recessions. Sites were treated with either CAF + SCTG (control) or CAF + ozone-enriched A-PRF (test). Clinical parameters were assessed at baseline, 90, and 180 days. Data were analyzed using the Shapiro-Wilk, repeated measures ANOVA, Tukey, and Friedman tests (α=0.05) on GraphPad Prism 8.0®. This study adhered to the CONSORT guidelines for randomized clinical trials. Results: Complete root coverage (100%) was achieved in 13 of 22 sites (60%) in the SCTG group and in nine of 22 cases (43%) in the ozone-enriched A-PRF group. Both groups statistically and significantly improve over time in selected clinical parameters (p<0.05). The SCTG group showed significant gains in all evaluated outcomes, whereas the ozone-enriched A-PRF group showed significant improvements in clinical attachment level, recession height, recession width, and dentin hypersensitivity. SCTG more greatly increased gingival thickness (0.77±0.52 mm) and keratinized tissue width (0.81±0.95 mm) than ozone-enriched A-PRF (0.27±0.55 mm and 0.22±0.42 mm, respectively). Conclusions: Both treatment approaches effectively managed Cairo Class I gingival recessions. SCTG promoted superior soft tissue augmentation, whereas ozone-enriched A-PRF achieved comparable reductions in recession-related parameters. The limitations of this study include its short follow-up period and the absence of histological assessment. Clinical Trial Register: RBR-537bzqt
Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm in the oral cavity, characterized by high morbidity and mortality. Various proteins, including matrix metalloproteinases (MMPs), have been investigated as potential biomarkers for diagnosing and prognosing this disease. Objective: To evaluate the utility of MMP-2, MMP-9, and the tissue inhibitor of metalloproteinase-2 (TIMP-2) as biomarkers in diagnosing and prognosing OSCC. Methodology: This retrospective case-control study involved 60 cases and 30 controls from the University Hospital Fundación Santa Fe de Bogotá, part of the Colombian cohort of the InterChange/Headspace study. Saliva samples were collected using a 60-second mouth rinse with 10 mL of sterile saline solution, along with serum and oral tissue samples and clinical and sociodemographic data. MMP-9, MMP-2, and TIMP-2 concentrations in saliva were determined using ELISA, whereas tissue samples were analyzed by immunohistochemistry. MMP activity in saliva was quantified using a generic activity assay. Results: Salivary MMP-9 and MMP-2 concentrations were significantly higher in cases than in controls, whereas no significant differences were observed for TIMP-2. ROC curve analysis showed excellent discriminatory capacity for salivary MMP-9 (AUC=0.946; sensitivity=0.817; specificity=0.867), good performance for MMP-2 (AUC=0.708; sensitivity=0.717; specificity=0.633), and lower discriminatory ability for TIMP-2 (AUC=0.630; sensitivity = 0.617; specificity=0.500). Elevated MMP-9 concentrations were observed in 33% of the serological samples. The immunohistochemistry of MMP-2, MMP-9, and TIMP-2 showed differences between cases and controls. Conclusions: This study highlights salivary MMP-9 and MMP-2, together with MMP activity, as biomarkers of interest for OSCC that may contribute to the understanding of disease-related molecular changes detectable by liquid biopsy. While elevated salivary levels were observed in OSCC cases when compared to controls, these findings should be interpreted as exploratory. Elevated serological MMP-9 levels were observed in a small subset of cases. However, the limited sample size and the absence of a control group in this study preclude diagnostic interpretation. Larger, well-powered, and externally validated studies are required to determine the potential clinical utility of these biomarkers.
Squamous cell carcinoma of head and neck
Assessment of chitosan addition to at-home bleaching gel with and without calcium on the physical properties of tooth enamel
Dental bleaching is a widely used esthetic treatment, but concerns persist regarding its potential effects on enamel integrity. The incorporation of remineralizing and protective agents into bleaching gels, such as calcium and chitosan, has been proposed to mitigate these effects. Objective: This in vitro study evaluated the effects of adding 2% chitosan to at-home bleaching gels with and without calcium on enamel physical properties. Methodology: Bovine enamel specimens stained with black tea were assigned to five groups (n = 12): control (no bleaching), 7.5% hydrogen peroxide (7.5% HP), 7.5% HP + 2% chitosan (7.5% HP+ Chi), 7.5% HP + calcium (7.5% HP + Ca), and 7.5% HP + calcium + chitosan (7.5% HP + Ca + Chi). Bleaching was performed for 14 days (1 hour/day). Color (∆L*, ∆a*, ∆b*, ∆Eab, ∆E00, and ∆WID), surface roughness, and surface microhardness (SMH) were evaluated at baseline (T1) and after treatment (T2). Mineral content (Ca, P, and the Ca/P ratio) was assessed by energy-dispersive X-ray spectroscopy and enamel morphology by scanning electron microscopy. Statistical analyses included the Kruskal-Wallis and Dunn's tests, mixed models, and ANOVA. Results: Groups containing chitosan (7.5% HP + Chi and 7.5% HP + Ca + Chi) showed the lowest surface roughness and the highest microhardness values. For these groups, SMH showed no decrease after treatment (T2), remaining similar to the initial values (T1). Color changes were similar among all bleached groups. Calcium, phosphorus, and Ca/P levels were the same for all groups. Conclusion: Adding 2% chitosan to 7.5% hydrogen peroxide-based at-home bleaching gels appears to be a promising approach to protect enamel against changes in roughness, microhardness, and mineral content without compromising bleaching efficacy.
Integrated analysis identifies CCNA2 as a candidate diagnostic and prognostic biomarker in oral tongue squamous cell carcinoma
Background Oral tongue squamous cell carcinoma (OTSCC) is an aggressive malignancy with poor prognosis, necessitating reliable biomarkers. Methodology Genes with significantly higher expression in OTSCC tumor tissues compared to normal tongue tissues were identified via integrated transcriptomic analysis of seven GEO datasets. To assess their diagnostic and prognostic potential, these genes were further characterized using multi-omic and clinical data from the TCGA-OTSCC and CPTAC-OTSCC cohorts. Results A total of 1,117 genes were found to be upregulated in OTSCC tissues, among which only CCNA2 (Cyclin A2) was significantly associated with both reduced overall survival (OS) and disease-free survival (DFS) in the TCGA-OTSCC cohort (n=128), based on Cox proportional hazards regression and Kaplan–Meier analyses. CCNA2 showed moderate prognostic performance (AUC=0.63 for OS; AUC=0.65 for DFS) and was significantly upregulated in higher-grade tumors (p=0.01) and in deceased patients (p=0.03). No somatic mutations or promoter methylation alterations were observed in CCNA2 based on TCGA data. In CPTAC-OTSCC samples (n=18), CCNA2 protein expression was significantly higher in tumor tissues than in non-tumoral tissues (p <0.0001), with a positive correlation between mRNA and protein levels (r=0.56, p=0.01). Both mRNA and protein forms showed strong diagnostic performance (AUC=0.92 and AUC=0.82, respectively), consistent with observations across multiple tumor types. While CCNA2 protein levels showed prognostic relevance for OS (AUC=0.69, p=0.01), the mRNA-based prediction did not reach statistical significance (AUC=0.63, p=0.36). Functional enrichment analysis of CCNA2 co-expressed genes predicted involvement in cell cycle, mismatch repair, and DNA replication pathways. Additionally, protein–protein interaction analysis positioned CCNA2 as a central hub, suggesting its potential role in OTSCC pathogenesis. Conclusions These findings indicate that CCNA2 is a promising diagnostic and prognostic biomarker candidate in OTSCC. Given the small size of the CPTAC validation cohort, further studies in larger, independent OTSCC cohorts are warranted to confirm its clinical utility.
Evaluation of bleaching efficacy and cytotoxicity of an experimental hydrogel containing MnO-Doped Biosilicate® activated by violet LED light
Although hydrogen peroxide (HP) at 35% is effective in dental bleaching, the cytotoxicity associated with its use remains a significant concern. In this context, this study aimed to develop a bleaching hydrogel containing 6% HP, Biosilicate® (BioS) doped with manganese oxide (MnO_BioS), and irradiated with violet LED light (LED). Enamel/dentin discs were submitted to the following bleaching treatments (n=08): 35%HP (positive control), 6%HP gel containing BioS or MnO_BioS (0 and 10 wt%), with or without LED irradiation. The discs were adapted to artificial pulp chambers (APCs), with the enamel exposed for bleaching and the dentin facing the culture medium (DMEM). Bleaching was performed in three 30-minute sessions with 7-day intervals. After bleaching, the extracts (DMEM + bleaching gel components diffused through the discs) were collected and applied to the odontoblast-like MDPC-23 cells. Color change (ΔE00) and changes in the whiteness index (ΔWID) were determined before (T0) and after the last bleaching session (T2). Cell viability (MTT, %), HP diffusion (µg/mL), oxidative cell stress (OxS), and cell fluorescence (live/dead assay, by confocal microscopy) were assessed after the first session (T1). The data were analyzed using ANOVA and Tukey’s test (p=0.05). The addition of 6%HP_MnO_BioS_LED exceeded ΔWID compared to 35%HP, showing statistical differences from the other groups, while ΔE00 was statistically similar to 35%HP. 6%HP_MnO_BioS_LED demonstrated higher cell viability, lower HP diffusion, and reduced oxidative stress (OxS) compared to the other groups (p<0.05). 6%HP_MnO_BioS_LED increased bleaching potential and presented lower cytotoxicity compared to 35%HP.
Notch2 is involved in regulating apical tissue repair following severe intrusive luxation
This study aims to characterize apical repair dynamics in immature permanent teeth after severe intrusive luxation, and to explore Notch signaling pathway regulation in this process using a Sprague-Dawley rat model. Methodology In this study, a modified tool was utilized to establish an intrusive luxation model in SD rats. Tissue repair was assessed via micro-computed tomography (Micro-CT) and hematoxylin-eosin (H&E) staining. Differential gene expression analysis of stem cells from the apical papilla (SCAPs) was performed using the publicly available GEO dataset. Immunohistochemical detection of Notch2 receptor expression in the apical region of injured teeth was subsequently conducted, guided by bioinformatics screening. Finally, the Notch signaling pathway was pharmacologically inhibited using DAPT (γ-secretase inhibitor), and its impact on post-injury prognosis was evaluated. Results Histological analysis revealed prevalent pulp hypoplasia and apical tissue fibrosis after injury. Differential gene analysis suggested that the Notch signaling pathway, particularly Notch2, is involved in the regulation of angiogenesis-related pathways in SCAPs. Immunohistochemistry showed positive Notch2 expression in fibrotic apical regions. Notably, inhibition of Notch signaling significantly reduced aberrant fibrosis while enhancing vascular proliferation in the injury site. Conclusions Severe intrusive luxation is primarily characterized by aberrant fibrous differentiation in the apical region. The Notch signaling pathway may negatively regulate angiogenesis in the damaged apical area, suggesting that targeted inhibition of this pathway could promote tissue repair following embedded dental injuries.
Bioactive luting cements on the adhesive interface of fiber post and root dentin
Innovative self-etching dental cements have been considered a versatile material with recent formulations incorporating bioactive additives. Objective This study analyzed the role of these ingredients in systems used for luting intracanal posts. Methodology Bond strength (BS), water sorption (WS), water solubility (WSB), and in situ zymography (IZ) were assessed. Three cements were tested: RelyX U200 (RU, bioactive-free control), RelyX Luting Plus (RL, fluoride-containing glass-ionomer), and BeautiCem SA (BC, S-PRG-based). Bond strength was evaluated in bovine root dentin (n=10) at the cervical, middle, and apical thirds at 7 days and 6 months. WS/WSB were assessed using 10 cement disks (10×1 mm) cycled through deionized water immersion (m1), desiccation (m2), and a second immersion (m3). For IZ, the specimens (n=3) were sectioned and incubated with fluorescein-conjugated gelatin for 48h at 37°C at both storage times (7 days and 6 months) for analysis by Confocal Laser Scanning Microscopy. Fluorescence intensity was quantified using Image J. Data were analyzed using ANOVA and Tukey’s test (p<0.05). Results RU presented the highest BS and the lowest WS/WSB, while RL showed the opposite trend. BC demonstrated intermediate performance with no statistical differences from the other materials. For all cements, the cervical third and the 6-month period yielded the highest BS values. WS/WSB were greater for the bioactive cements (BC, RL). IZ results aligned with BS findings, revealing suppressed enzymatic activity over time. Based on these results, it can be concluded that RU exhibited superior mechanical stability despite lacking bioactivity. Conclusion Among bioactive cements, BC emerged as an interesting alternative, offering improved bond strength, water stability, and bioactive potential compared to RL.
Copyright (c) 2026 Tiago Carvalho dos Santos, Giovanna Speranza Zabeu, Ana Carolina Almeida Lima, Mylena Proença Costa, Marcela Rocha Carrilho, Linda Wang https://creativecommons.org/licenses/by/4.0
Tooth discoloration is a frequent concern among dental patients. While many professionals and patients choose veneers or other invasive solutions, Minimal Intervention Dentistry (MID) recommends non- and microinvasive approaches to preserve tooth structure. Objective To assess Brazilian dentists’ knowledge and practices on tooth discoloration and how education and professional profile may influence them. Methodology A cross-sectional observational study was conducted with 384 volunteer dentists via an online series of questions on causes, diagnosis, treatment (per tissue removal), and professional-patient relationship. Answers were scored (1=correct/affirmative, 0=incorrect/negative). Descriptive and multivariate regression analyses were performed (α=0.05). Results Most respondents were female, aged 20-49, from the Southeast region. Correct answer rates: 69.9% for causes, 69.4% for diagnosis, 48.8% for treatment, 83.6% for professional-patient relationship, 56.4% overall. Graduation from public universities and holding graduate training in Operative or Pediatric Dentistry or Orofacial Harmonization were associated with better outcomes. Conclusion Knowledge of non- and microinvasive approaches to tooth discoloration remains limited. Broader educational efforts are needed, especially among specific groups of professionals who showed lower performance.
Effects of bromelain, melatonin, and thymoquinone on neutrophil extracellular trap formation and macrophage polarization in experimental periodontitis
Periodontitis is a chronic inflammatory disease characterized by dysregulated immune responses leading to alveolar bone loss. Formation of neutrophil extracellular traps and macrophage polarization play critical roles in its pathogenesis, and natural agents with immunomodulatory properties are being investigated as potential adjunctive therapies. Objective This study aimed to compare the effects of systemically administered melatonin, bromelain, and thymoquinone on serum neutrophil extracellular trap formation and macrophage polarization in experimental periodontitis. Methodology Forty rats were assigned to five groups: control, experimental periodontitis, and experimental periodontitis treated with melatonin, bromelain, or thymoquinone. Periodontitis was induced by ligature placement for 14 days. After ligature removal, the treatment groups received daily oral doses of melatonin, bromelain, or thymoquinone for 14 consecutive days. Biochemical, histologic, histomorphometric, and immunohistochemical analyses were performed. Comparisons between groups were performed using one-way ANOVA. Neutrophil extracellular trap levels measured before and after treatment within the same group were analyzed using a paired t-test. Results Thymoquinone treatment significantly reduced alveolar bone loss compared to the bromelain and melatonin groups (p=0.00). The highest value was observed in the Periodontitis group and the lowest in the Thymoquinone group for neutrophil extracellular trap levels, with intergroup comparisons showing no statistically significant differences (p=0.597). All immunohistochemical analyses showed significant differences in all treatment groups compared to both the control and periodontitis groups (p=0.000). CD68(+) macrophages were most abundant in the periodontitis group and least in the Melatonin group (p=0.00). CD80 expression was highest in the Melatonin group and lowest in the Thymoquinone group (p=0.000), while CD206 expression was highest in the Bromelain group and lowest in the Thymoquinone group (p=0.00). Conclusion Thymoquinone exhibited comparatively more favorable patterns, and overall, all agents showed trends that may support their consideration as adjunctive approaches in periodontitis management.