Abstract in English:

Abstract The acquired enamel pellicle (AEP) consists of an organic, acellular, and bacteria-free film, formed in vivo as a result of biomolecules adsorption onto the tooth surface. It is composed of proteins, glycoproteins, lipids, phospholipids, and other macromolecules, such as carbohydrates. The AEP formation process is complex and can be divided into three stages: initiation, development, and maturation. The pellicle has two main layers: the globular and basal layers. The basal layer offers the most protection against demineralization, as the subsequent globular layer is weaker and less tenacious. The formation of the AEP can be influenced by various factors, such as the physicochemical properties of the teeth, location in the oral cavity, pathologies, and even the oral microbiota. With the advancement of “omics” techniques, it has been possible to observe the presence of acid-resistant proteins in the AEP, which allowed the development of the “acquired pellicle engineering” strategy. This strategy involves enriching and modifying the basal layer with acid-resistant proteins. Among these proteins, hemoglobin, statherin-derived peptide, and a protein derived from sugarcane stand out. The objective of this literature review is to provide a comprehensive overview of the AEP, detailing its composition, formation process, and protective functions. Additionally, the review aims to explore recent advances in the field of “acquired pellicle engineering,” highlighting the acid-resistant proteins of the AEP and their potential applications in dentistry. Finally, the review intends to highlight the clinical implications of these findings and how they may contribute to the development of new strategies for the prevention and treatment of dental pathologies according to published studies.

Abstract in English:

Abstract Submandibular salivary gland inflammation has been suggested as one of the mechanisms underlying impaired salivary secretion associated with sleep deprivation (SD). However, whether the salivary inflammatory response occurs to the same extent in paradoxical sleep deprivation with or without sleep recovery remains unknown. Objective: This study evaluated the extent to which inflammation influences salivary impairments associated with paradoxical sleep deprivation with or without sleep recovery. Methodology: Male Wistar rats were randomly assigned into three groups as control, partial SD (PSD) with sleep recovery for four hours a day and total SD (TSD). Paradoxical SD was carried out for seven days in the SD groups, after which saliva, blood, and submandibular gland samples were taken. Levels of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), and nitrite were determined in saliva, serum, and the submandibular salivary gland. Leucocyte count and neutrophil-lymphocyte ratio were determined in all groups. One-way ANOVA and the Tukey's post hoc tests were used for data analysis. P-values < 0.05 were considered statistically significant. Results: Levels of TNF-α, IL-6, and nitrite in the submandibular salivary glands were significantly higher in the TSD groups (p=0.04,p<0.001, p=0.03, respectively) than in the control. Saliva level of TNF-α was higher in the PSD and TSD groups (p=0.003 and p=0.01 respectively) than in the control. Neutrophil-lymphocyte ratio was significantly higher in both PSD and TSD groups than in the control (p<0.01 for both). Conclusion: While total SD produced higher inflammatory response in the submandibular salivary gland, four-hour sleep recovery ameliorated this impact. This finding suggests that sleep recovery is crucial to improve inflammatory salivary gland dysfunction induced by sleep deprivation.

Abstract in English:

Abstract Objectives: Depth of invasion (DOI) in oral squamous cell carcinoma (OSCC) guides treatment and prognosis but lacks three-dimensional (3D) insight. Thus, this study aimed to investigate the feasibility and accuracy of Lugol's iodine-enhanced micro-computed tomography (CT) for the 3D measurement of DOI in OSCC samples. Methodology: In total, 50 in vitro OSCC samples from Nanjing Stomatological Hospital (July 2022 to January 2024) were subjected to micro-CT imaging with a slice thickness of 50 μm following 3% Lugol iodine staining for 12 h, followed by pathological examination and staining. The panoramic diagnostic scanner digitally measured pathological DOI. The micro-CT DOI was measured by evaluating the voxel value of the boundary of the tumor lesion and comparing it with the pathological examination results. Experienced physicians analyzed both measurements, and statistical analyses were performed to determine their correlation. Results: Lugol iodine-enhanced micro-CT imaging distinguishes various tissue structures, such as tumor tissue, epithelial tissue, muscle tissue, blood vessel structure, and other major tissue structures in 3D space. This imaging technique found and localized micro-tumor lesions (1.82×1.5×1 mm3) when in conjunction with pathological sections. Statistical analysis indicated a strong correlation between pathological DOI and micro-CT DOI (P<.001; r=0.986). During DOI measurement, Lugol iodine-enhanced micro-CT imaging effectively compensated for the loss of 3D space information in the pathological measurements, improving the accuracy of the DOI measurement. Conclusions: Lugol iodine-enhanced micro-CT improves OSCC DOI 3D measurements, enhances pathological staging accuracy, and aids treatment decisions and prognosis.

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Abstract Guided bone regeneration (GBR) is an alternative treatment for craniofacial bone defects reconstruction through membrane barrier adaptation, such as demineralized dentin material membrane (DDMM). DDMM is used as a substitute for GBR material, which aligns with Green Economy principles, it has a good biological osteoinductive and osteoconductive effects, and its structure resembles bones. The balance of bone remodeling when experiencing craniofacial defects will be altered and allow changes to resorption activity, so the mechanisms of osteoclastogenesis and bone resorption are vital. Objective: this article aims to analyze the expression of TNF-α, RANKL, and osteoclast cells count after application of DDMM as GBR in mandibular bone defects. Methodology: this is an experimental study with a post-test only control group design, which began with the randomization of 120 rats into five groups: K(−), without membrane implantation; K(+), PPCM; P1, DDMM; P2, DDMM + bone graft; P3, PPCM + bone graft. The expression of TNF-α, RANKL, and osteoclast cells count were observed, followed by analysis using a one-way ANOVA and post hoc Tukey HSD comparison test. Results: there were significant differences in the expression of TNF-α, RANKL, and osteoclast cells count in all study groups (p=0.000). TNF-α showed a decreasing difference with the highest expression in the K(−) group on day 3 of 12.00±2.16. RANKL expression increased on day 14 and decreased on day 21 in all groups. The osteoclast cells count generally showed a critical period with the highest increase in the K(−) group on day 14 of 73.00±0.00. Conclusion: DDMM has the potential to be a superior membrane substitute compared to PPCM as GBR in alternative treatment for craniofacial bone defects reconstruction.

Abstract in English:

Abstract Aim To evaluate the clinical effectiveness of ozonated sunflower oil (Oz) as an adjunctive of non-surgical periodontal therapy in patients with type 2 diabetes mellitus (DM2), on fibroblast cell viability and migration and the effectiveness of Oz on a Candida albicans (C. albicans) culture. Methodology In total, 32 sites in 16 DM2 with moderate to advanced periodontal disease with periodontal pocket depths ≥5mm were selected. The treatments were divided into two groups: control, saline solution (SS) as an adjunctive of scaling and root planing (SRP+SS), and test, Oz as an adjunctive of SRP (SRP+Oz). Hematological [fasting glucose level (FGL) and hemoglobin A1c (HbA1c)] and microbiological samples were collected from the participants at baseline and three months after periodontal treatment and the microbiological samples were analyzed by PCR. C. albicans was previously tested by the agar diffusion test. The effect of Oz was tested on cell viability and fibroblast migration. Results The groups showed no statistically significant differences (paired t-test-p>0.05) regarding hematological parameters, FGL (median - baseline 171.41, 3 months 164mg/dL), and HbA1c (baseline 8%, 3 months 7.5%) (Kruskal-Wallis One-Way Nonparametric-p>0.05) after periodontal therapy. The groups showed statistical differences for periodontal parameters between baseline and three months (paired t-test-p<0.05). PCR analysis showed a reduction in the percentage of C. albicans in the SRP+Oz group after three months (McNemar’s test-p=0.002). Cell viability was lower in the high glucose Dulbecco’s modified Eagle’s medium (4500 mg/L) than in low glucose (1000 mg/L) (RM-ANOVA-p<0.0001). The wound healing test showed reduced fibroblast migration (one-way ANOVA with Dunnett’s post-test-p<0.01). Oz showed high C. albicans antifungal inhibition (Kruskal-Wallis test-p=0.0001). Conclusions SRP+Oz effectively reduced C. albicans in-vitro and in-vivo but showed no clinical improvements compared to the control. Cell viability and wound healing of fibroblasts showed no improvements.

Abstract in English:

Abstract Objective This study evaluated whether hypoglycemic drug metformin enhances the anti-cancer effects of cisplatin in YD-9 cells. Methodology YD-9 cells, derived from oral mucosal squamous cell carcinoma of oral mucosa, were used to assess the combined effects of metformin and cisplatin by means of MTT assay, live and dead cell staining, and colony formation assays to evaluate cell viability and proliferation. Reactive oxygen species level was measured using a Muse cell analyzer. Apoptosis, epithelial-mesenchymal transition, and related molecular pathways were analyzed by western blot. Wound healing assays and Transwell migration assays examined cell migration, whereas monophosphate-activated protein kinase inhibitor Compound C, was utilized to investigate the AMPK pathway. Results Sequential treatment of YD-9 cells with metformin and cisplatin resulted in decreased cell viability and proliferation, increased ROS levels, and elevated apoptosis compared with the individual drugs. Moreover, the treatment inhibited EMT, wound healing, and cell migration. These results correlated with increased AMPK phosphorylation, a key regulator of cellular energy homeostasis. Introduction of Compound C pre-treatment upregulated N-cadherin and α-smooth muscle actin along with enhanced cell migration. Conclusion This study found synergism in anti-cancer effects between metformin and cisplatin. Additionally, introduction of Compound C confirmed that EMT inhibition is AMPK dependent. These findings indicate the potential use of metformin as an adjunct drug in anti-cancer treatments, warranting further investigation.

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Abstract Ionizing radiation directly affects hard dental tissues, compromising the dental structure, which results in damage to dentin collagen fibers and impacts the integrity of the dentin-enamel junction (DEJ). Objective To evaluate the effects of radiotherapy on the chemical composition and mechanical properties of human cervical dentin. Methodology Ten third molars were divided into control/non-irradiated and irradiated groups (n=5). The irradiated teeth were subjected to in vitro radiotherapy with the following protocol: 1.8 Gy daily, five days per week for eight weeks, totaling 72 Gy. The dentin in the cervical region was evaluated for each group. The chemical composition was assessed using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy, focusing on the mineral/matrix ratio (M:M), carbonate/mineral ratio (C:M), and amide I/amide III ratio. Amide I/CH2 ratio was used to assess collagen quality, as amide I reflects protein conformation and hydrogen bonding, while CH2 indicates side-chain vibrations with low sensitivity to molecular orientation. Nanohardness and elastic modulus were evaluated by instrumented indentation. Scanning electron microscopy (SEM) was used to assess the enamel’s morphology. Statistical analysis of each parameter was performed using a t-test. Results The FTIR analysis showed statistically significant differences in the C:M ratio (p=0.004) and amide I/amide III ratio (p=0.007). Raman spectroscopy revealed significant differences in the M:M ratio (p<0.001), as well as in the amide I/amide III (p<0.001) and amide I/CH2 ratios (p<0.001). Additionally, nanohardness (p=0.04) and the elastic modulus (p=0.003) showed statistically significant differences. SEM images revealed sound dentin shows normal tissue organization, whereas irradiated dentin showed no clear limit between peri and intertubular dentin. Conclusions Radiotherapy induced significant changes in dentin composition and mechanical properties, characterized by increased organic content and phosphate levels, reduced carbonate, and decreased nanohardness and elastic modulus. These findings highlight the adverse effects on dentin's structural integrity.

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Abstract Objective To evaluate the association between non-syndromic cleft lip with or without cleft palate (NSCL±P) and tooth agenesis (TA), as well as the association of both conditions with polymorphisms in genes encoding growth factors. Methodology This cross-sectional study included children with NSCL±P and a control group of children without NSCL±P. Permanent teeth TA (excluding third molars) was evaluated using panoramic radiographs by a trained examiner. Only TA located outside the cleft was considered in the NSCL±P group. Genetic polymorphisms in Transforming Growth Factor Beta 1 (TGFB1)–rs1800470 and rs4803455–Transforming Growth Factor Beta Receptor 2 (TGFBR2)–rs3087465 and rs764522–Epidermal Growth Factor (EGF)–rs4444903 and rs2237051–and Epidermal Growth Factor Receptor (EGFR)–rs2227983– were genotyped by real-time PCR allele discrimination from buccal cell samples. Associations were tested by uni and multivariable Poisson regression models (5% significance level). Results A total of 243 children–127 with NSCL±P (mean age = 8.80±2.14 years) and 116 without NSCL±P (mean age = 8.58±2.03 years) were included. TA was more frequent in the NSCL±P group (23.8%) than in the control group (6.2%) (p<0.01). The EGF rs2237051 was significantly associated with NSCL±P, independently of the other variables (PRa=1.41; p=0.042). Regarding TA, only the cleft presence was associated with a higher prevalence of TA regardless of different variables (PRa=3.70; p=0.001). There was no association between TA and the investigated genetic polymorphisms. When TA and NSCL±P were considered together, a borderline association was observed with rs1800470 in TGFB1 (p=0.06). Conclusion NSCL±P is associated with TA outside the cleft area. The EGF rs2237051 was associated with NSCL±P. Polymorphisms in genes encoding growth factors are not associated with TA.

Abstract in English:

This article is derived from Irisvaldo Lima Guedes's Master's dissertation and is available at the address: https://sigaa.ufpi.br/sigaa/public/programa/noticias_desc.jsf?lc=pt_BR&id=370¬icia=519307121

Abstract in English:

Abstract Inflammation, oxidative damage, and adenosine triphosphate (ATP) depletion play a role in the pathogenesis of cisplatin (CIS)-induced oral mucositis. Objective: The purpose of this research is to examine the impact of ATP against potential oral mucositis development in cisplatin-treated rats. Methodology All rats were randomly assigned to four groups, namely healthy control group (HG), ATP group (ATPG), Cisplatin group (CISG), and ATP + Cisplatin group (ATCS). Firstly, ATP 4 mg/kg was administered via intraperitoneal injection (IP) to both ATPG and ATCS groups. The same volume of normal saline was injected into HG and CISG groups. After 1 h, cisplatin 5 mg/kg was administered via IP to CISG and ATCS groups. The drugs were taken 1x1 for 7 d. Later, tongue tissues were collected from all groups. Biochemical, macroscopic, and histopathological examinations were performed on all tissues. Results: ATP inhibited cisplatin-induced oxidative damage and pro-inflammatory cytokines levels in tongue tissue. In the CIS group, a significant number of distinct sulcus formations were found in the apex and corpus, as well as a few ulcer foci in the corpus, significant papilla loss, and bleeding. Meanwhile, in the ATP group, a similar appearance to healthy tissue was observed. Histopathologically, it was determined that in cisplatin-aggravated tongue tissue damage, filiform papillae decreased when ATP was administered, and the arrangement and structures of the epithelium, blood capillaries, muscle groups, and adipose cell groups were normal. Conclusions: Oral mucositis caused by cisplatin is alleviated by ATP. These findings may be useful for developing new therapeutic approaches to prevent or treat mucositis, a side effect so severe that can lead to treatment discontinuation.

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Abstract Introduction: According to the latest international consensus in 2018, sleep bruxism is the activity of the masticatory muscles during sleep characterized by rhythmic or non-rhythmic teeth clenching or grinding. Regarding its harmful effects, bruxism is considered one of the predisposing factors of tooth wear and temporomandibular joint diseases. Occlusal splint therapy is the most frequently used treatment for minimizing these harmful effects. Objectives: This study compared the volumetric wear loss and pain scores between digitally and conventionally manufactured occlusal splints for individuals with sleep bruxism. Methodology: A total of 30 individuals diagnosed with sleep bruxism were selected following the inclusion criteria and randomly divided into two groups. Pain scores were subjectively reported using a visual analog scale. Volumetric wear loss of the occlusal splint surface was measured using the Geomagic software. Data were analyzed with SPSS version 25.0. Results: At the six-month follow-up, conventionally manufactured splints (103.53±41.23) showed a volumetric loss significantly higher than that the digital ones (62.33±26.29) (p=0.005). We found no significant difference between the two splint types regarding VAS scores. Conclusion: Occlusal splint wear can gradually alter the balance of occlusal contact and potentially reduce its therapeutic effectiveness, highlighting the importance of using wear-resistant materials. Our findings indicate that digital manufacturing processes provide advantages due to their long-term clinical outcomes.

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Abstract Chitosan nanoparticles suspension (ChNPs) showed antimicrobial effects in the oral cavity, but its effects on enamel erosion prevention remain little explored. Objective This study synthesized ChNPs and evaluated their effect on enamel after erosive challenge. Design ChNPs were synthesized by ionic gelation and characterized using scanning electron microscopy (SEM), infrared spectrophotometry (FTIR), dynamic light scattering methods (DLS) and zeta potential (ZP). In total, 56 human enamel blocks were divided into four groups (n=14/group): (i) ChNPs suspension (4.4mg/mL); (ii) 0.05% sodium fluoride solution (NaF); (iii) chitosan solution (5.0 mg/mL); and (iv) distilled water. After incubation in freshly collected human saliva (3h), the samples were exposed to erosive challenge in 1% citric acid (90s) and remineralizing solution (2h) performed four times a day. After the 1st and 4th acid exposures, solutions were applied for 2 min. After 7 days, % Vickers surface hardness change (% SMH) was obtained using 300 g load applied for 15s. Enamel surface loss was evaluated using optical profilometer by subtracting the final profile values from baseline ones. Data were analyzed by ANOVA and post-hoc T tests (α=0.05). Surface topography was obtained by optical profilometer. Results SEM revealed the formation of spherical nanoparticles. DLS showed nanoparticles with 85.7±10.5 nm diameter and ZP value of +45.5±5.4mV. Enamel surface loss was significantly lower in ChNPs and NaF groups, exhibiting a less rough surface in the treated areas. ChNPs, NaF and chitosan groups showed lower % SMH values. Conclusions ChNPs suspension minimized enamel loss after in vitro erosive challenge and appears to be a promising material for enamel erosion prevention.

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Abstract Objective: To evaluate the possible clinical association between dental fracture and the presence of amalgam restorations, including other restorative treatments in the control group. The potential association of fractures with dental wear facets and the restoration size was also assessed as a secondary objective. Methodology: Patients with fractured teeth restored with silver amalgam or not were included as the case group (n=25). The control group, with non-fractured teeth, was selected after considering the case group aspects, with twice as many patients (n=50) with posterior teeth sound or restored (amalgam, composite resin, or another restorative material). For both groups, the type of restorative material, extension of the restorations, remaining tooth structure, and the presence or absence of wear facets were analyzed. The teeth were impressed with alginate, and from the plaster models, the extent of fractures or restorations was measured by two calibrated examiners with a digital caliper at the cervico-occlusal and bucco-lingual directions. The data were subjected to the Chi-square test (5%) and odds ratio. Results: There was no statistical difference between the presence or absence of amalgam restorations regarding the risk of tooth fracture. Regarding fractures larger than 3.5mm, the chances of failure are 0.53 for amalgam restorations with no statistical differences (p=0.433), and, regarding the presence of wear facets, the odds ratio of failure is 1.357 for amalgam restorations (p=0.65). Conclusion: It can be deduced that, within the conditions of the study, no discernible association exists between dental fractures and the presence of silver amalgam restorations. Clinical Trial Register: (ReBEC) UNT code U1111-1215-7255.

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Abstract Pulpitis, which is often triggered by caries and trauma, is a significant clinical challenge due to its prevalence. This research aims to uncover potential metabolic biomarkers for pulpitis and map out the implicated metabolic pathways, thereby laying a foundation for enhanced diagnostic and preventive strategies. Methodology We analyzed pulp samples from 12 participants (six who had pulpitis and six who had healthy teeth) using serum metabolomics via ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry. Important biomarkers were pinpointed via multivariate analysis and orthogonal partial least squares discriminant analysis. Additionally, correlation and biomarker pathway enrichment analyses were conducted to explore the relations between differentially expressed biomarkers and their associated biological pathways. Specific metabolites of interest were further examined via alkaline phosphatase (ALP) staining, Alizarin Red staining, and RT-qPCR analysis. Results We identified 22 significant biomarkers (13 increased, nine decreased) related to 18 metabolic pathways in pulpitis cases. Key biomarkers included ascorbic acid, inosine, allopurinol riboside, and L-asparagine, in which ascorbic acid and inosine showed the most substantial downregulation and strongest association with pulpitis. Notably, aminoacyl-tRNA biosynthesis and retrograde endocannabinoid signaling pathways were closely linked with pulpitis. Ascorbic acid enhanced the osteogenic differentiation, calcium deposition, as well as the expression of osteogenic genes of human dental pulp stem cells (DPSCs).Conclusions: The identified biomarkers and metabolic pathways offer insights into the pathogenesis of pulpitis and have potential applications in developing preventive treatments.

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Abstract The nasopalatine duct cyst (NPDC) is the most common nonodontogenic jaw cyst, with a higher prevalence reported in males. Diagnosing jaw cysts remains challenging for general dentists due to their overlapping clinical and radiographic presentations. An updated case series and integrative literature review may assist in improving the accurate diagnosis of NPDC. Objective This study aimed to describe the clinicopathological and imaging characteristics of 63 NPDC cases and to review previously reported cases in the literature. Methodology An international, multicenter, retrospective NPDC case series was conducted. Demographic, radiographic, and histopathological data were collected from clinical records. Additionally, a PubMed/MEDLINE search was performed to identify articles on NPDC. Results A total of 63 NPDC cases were evaluated, with a mean patient age of 47 years and no significant sex predilection. Twenty-one cases were asymptomatic, while 34 presented with symptoms such as pain and swelling. Radiographically, NPDC appeared as a well-defined radiolucent lesion located between the upper central incisors, bordered by a radiopaque margin. The integrative literature review identified 67 studies, comprising 51 case reports, 12 retrospective studies, and four case series, totaling 1,003 reported NPDC cases. The clinicopathological and radiographic findings from the literature aligned with those in this case series. Conclusion The 63 cases analyzed in this study showed consistent findings across six international centers, with no sex predilection observed, contrasting with the male dominance reported in the literature. NPDC should be considered in the differential diagnosis of intraosseous lesions in the anterior maxilla. Accurate diagnosis requires a combination of radiographic and histopathological evaluations to prevent misdiagnosis and improper treatment.

Abstract in English:

Abstract Aim This cross-sectional study investigated the salivary proteomic profile associated with generalized gingivitis in pregnant women with obesity. Methodology Pregnant women in the third trimester (≥27 weeks of gestation) were divided into two groups based on bleeding on probing (BOP): G1 (BOP>50%; n=9) and G2 (BOP 0–30%; n=9). Collected unstimulated saliva samples were individually analyzed using nano liquid chromatography electron spray ionization tandem mass spectrometry. Identified proteins were classified according to gene ontology for biological processes, molecular functions, immune system involvement, and cellular components. Differential protein expression was determined using thresholds of p<0.05 for downregulation and 1-p>0.95 for up-regulation proteins. Results Of the 183 identified proteins, 100 were shared between groups, totaling 57 up-regulated and 27 downregulated proteins in G1. Key biological processes included antimicrobial humoral response and hydrogen peroxide catabolism, with proteins linked to immune function and endopeptidase regulation. Functional analysis showed that Lactotransferrin (5-fold increase in G1), Haptoglobin (4-fold), and Immunoglobulin J chain (3-fold) were up-regulated, whereas Statherin (5-fold) and Protein S100-A8 (4-fold) were downregulated in G1. Conclusions Pregnant women with obesity and generalized gingivitis exhibited a distinct salivary proteomic profile characterized by the up-regulation of immune-related proteins and downregulation of tissue-protective proteins. These findings suggest potential salivary biomarkers for detection and targeted management of periodontal inflammation in this high-risk population.