Healthy Gingiva Research Articles

Fibroblast ferroptosis is involved in periodontitis-induced tissue damage and bone loss.

Periodontitis causes inflammatory destructions of tooth-supporting tissue and constitutes a significant burden on public health. Failing to reserve the tissue damage and bone loss by any of the currently available therapies has left periodontitis uncurable thus far. Understanding the molecular mechanism in the inflammatory process is crucial to elucidating the pathogenesis and enlightening new therapeutic strategies for periodontitis. This study was to investigate whether and how ferroptosis, a newly-discovered form of cell death, was involved in the pathogenesis of periodontitis. Healthy and periodontitis human gingiva samples were collected and ligature-induced periodontitis murine models were constructed to investigate the role of ferroptosis in periodontitis. Single-cell RNA sequencing data was analyzed to identify the cell type that underwent ferroptosis. The susceptibility of human gingival fibroblasts to ferroptosis was investigated by in vitro cell cultures. We found that gingival fibroblasts undergo ferroptosis in periodontitis, and that periodontitis-induced tissue damage and bone loss were alleviated by inhibition of ferroptosis. Periodontitis-induced pro-inflammatory immune responses was featured by profound elevation of fibroblast-derived Interleukin-6, which was attenuated by ferroptosis inhibition. These results indicated fibroblast ferroptosis as a new clue to unveiling the cellular and molecular basis for periodontitis-induced tissue damage. Involvement of ferroptosis/Interleukin-6 signaling in the pathogenic process suggested a potential target for immunopharmacological approaches to curing periodontitis.

Association Of Il18 Gene Polymorphism with Susceptibility to Periodontitis - A Case Control Study

Background: Cytokine IL18, also known as IFN-inducing factor, is an important regulator of innate and acquired immune responses and plays a number of roles in chronic inflammation and dysfunction autoimmune disorder. Several polymorphisms in the IL18 promoter region have been identified. As there is little evidence for IL18 polymorphisms and periodontitis, this study aimed to evaluate the genetic association of polymorphisms of the IL18 gene (rs1946518). Materials and Methods: A total of 100 subjects were recruited for this study, including 50 patients with periodontitis (stage II, III and grade B) and 50 patients with healthy gingiva clinically intact periodontium. Genomic DNA was extracted from the blood obtained from the subjects. DNA was amplified using primers specific to the MseI region of the IL18 receptor gene. Amplicon was further genotyped using the restriction fragment length using the BtgI enzyme. Genotyping obtained on the basis of the RFLP model was recorded and used for statistical analysis. The distributions of genotypes and allele frequencies in the periodontal disease group and the control group were compared using the Chi Square test. Risks associated with individual alleles or genotypes were calculated using odds ratios (ORs) with 95% confidence intervals. Statistical significance in all trials was determined at p <0.05. Result: The frequencies of genotypes and the distribution of IL18 receptor MseI polymorphisms were not significantly different at ꭕ2df (P = .818). The results of our study showed that there was no significant difference between homozygous and heterozygous genotypes (GG vs TG TT) between periodontitis patients and control group with a P value of 0.8316. The detection frequencies of the TG (20% vs 22%) and TT (14% vs 10%) genotypes showed a significant difference (P value = 0.8316) between the control and experimental groups. experience. There were no significant differences for the G allele (76% vs 79%) and the T allele (24% vs 21%) between the experimental and control groups. Conclusions: The present study indicated that the polymorphism of the IL18 gene was not associated with CP in the analyzed study group.

Yoga as an Integrated Holistic Approach to Oral Health: A Review.

The association between various systemic diseases and periodontitis has been explored extensively. A sedentary lifestyle plays a significant role in systemic and periodontal disease progression. Therefore, lifestyle modification has been considered a component of therapeutic aspects for periodontal disease and systemic disease. This review focuses on how yoga may reduce chronic gingival inflammation by improving the body's defense, which can act more efficiently on periodontal bacteria and help maintain healthy gingiva. A literature search was performed in PubMed/MEDLINE CINAHL, Web of Science, and Google Scholar for all the published articles related to yoga and its systemic benefits and potential role in reducing periodontal breakdown, and the findings were summarized. The practice of yoga therapy has been proven to show several benefits, such as reduced stress levels, anxiety and depression, increased antioxidant levels, reduced insulin resistance, and improved respiratory function. It also helps to improve the immune system. Yoga can be used as a potential treatment modality adjunct to conventional periodontal therapy as it has been shown to have a potential benefit in controlling systemic risk factors.

Gingival Pigmentation Pattern in Correlation to Skin Color in a Group of Kurdish People in Sulaimani City

Background: Melanin pigmentation of the gingiva appears in all ethnicities. Excessive pigmentation is an esthetic concern that has increased awareness about depigmentation procedures. This epidemiological study aims to find the correlation between skin color and gingival pigmentation in Sulaimani Governorate, Kurdistan/Iraq. Subjects and Methods: A total of 820 apparently healthy and non-smokers, including 338 males and 482 females with healthy gingiva, aged between (18-40 years old) were enrolled in this study. Clinical examination on the participants’ gingivae was performed to assess color, and the distribution of pigmentations. Afterward the of participants skin color were visually examined and divided into six groups according to the Fitzpatrick scale. Results: Skin color of (53%) of our participants was medium to light brown. Most of the pigmentations were observed in the attached gingiva and interdental papilla (26.83%) and least being in the marginal gingiva and interdental papilla (9.27%). A statistically significant correlation was found between the participants’ skin color, and the intensity of their gingival pigmentations Conclusion: Darker-skinned subjects haveeavieringival pigmentation compared toair-skinned people in Sulaimani Governorate, Kurdistan/ Iraq. The intensity of gingival pigmentation increases with age with the highest rate of gingival pigmentation was in the upper and lower second premolar to premolar area.

MEMSbased Double-Stacked Tower Biosensor Array with Integrated Readout Circuitry for Detection of Salivary pH as a Diagnostic Biomarker Applied for Chronic Periodontal Disease.

MEMS based 3D double stacked tower pixel biosensor 10 × 10 array with integration of readout circuit for detection of saliva pH ion is demonstrated. The pixel biosensor comprised a driving electrode, sensing electrode and double stack tower pixel structure. The sensitivity of double stacked tower biosensor can be auxiliary enhanced by proposed lower-jitter low dropout regulator circuit and dual offset cancellation comparator. The double stacked tower sensor is fabricated by MEMS backend-of-line CMOS process, it is compatible with CMOS frontend readout circuits and integrated as a system-on-chip (SoC). The double stacked tower pixel by MEMS process is to obtain a larger volume ratio of charge groups in a pixel of biosensor to enhance the sensitivity and linearity for ion detection. With the double stacked tower structure in biosensor, the sensitivity is improved by 31% than that of single tower structure proved by simulation. A wide-range linearity from pH 2.0 to pH 8.3, high sensitivity of -21 ADC counts/pH (or 212 mV/pH), response time of 5 s, repetition of 98.9%, and drift over time of 0.5 mV are achieved. Furthermore, the proposed biosensor was performed to confirm the artificial saliva from healthy gingiva, chronic gingivitis and chronic periodontitis, the measured ADC counts from proposed biosensor SoC was in consistent of that measured cyclic voltametric (CV) method very well. The proposed 3D double stack tower biosensor and readout circuit can be further integrated with internet-of-thing (IoT) device and NFC for data transmission for continuous pH sensing to facilitate the chronic gingiva disease health care at home.

Influence of interdental embrasures on interdental papilla

Background: There is growing attention on anterior esthetics by both dentists and patients, which emphasizes the need for conduct of study encompassing the anatomical features of an embrasure and correlating with papilla fill. Hence the present study has been designed to meet these parameters, including food lodgement.
 Aim: To assess the influence of anatomical and morphological characteristics of interdental embrasures on interdental papilla and food lodgement.
 Objectives: were set as the following:
 1.Correlation of Modified Papilla Index Score (PIS) with interdental anatomical measurements as follows:
 a. Distance between Contact Point and Bone Crest (CP-BC). b. Interdental Distance (IDD).c. Embrasure Space Area (EA).d. Crown Form (CF).e. Papilla Length (PL).
 2.To determine the optimal dimensions of interdental embrasure between maxillary incisors so as to be completely filled by normal healthy interdental papilla.
 3.To correlate occurrence of food lodgement with Modified Papilla Index Score (PIS) and Embrasure Space Area (EA).
 Materials and methods : 532 patients aged 18-58 years who had fully erupted permanent dentition and healthy gingiva with probing depth ≤ 3mm were included into the study. Quantitative analysis of interdental papillae were done using clinical parameters along with radiographic examination.
 Results : The clinical and radiographic assessment of 1312 interdental papillae revealed that the interdental anatomical factors viz (which are) CP-BC distance, IDD, EA, CF and PL significantly influenced the degree of papilla fill. The study also highlighted the possible occurrence of food lodgment in patients with open embrasures.
 Conclusion : Embrasure anatomical parameters and papillary heightvary widely among individuals. Interdental papillary deficiency is a relative phenomenon since it is an outcome of net influence of all the other parameters.

Orthodontıc treatment and oral flora

The general aim of orthodontic treatment is to provide ideal occlusion, facial aesthetics and stability in individuals, as well as to provide healthy periodontal structures. A good orthodontic treatment can be possible with healthy gingiva. Plaque accumulation may occur in the tooth areas around the equipment used in orthodontic appliances. The microbiological composition of dental plaque is related to dental and oral health. During the orthodontic treatment process, microbiological changes may occur in the flora. Therefore, before starting orthodontic treatment, the oral hygiene of the patient should be checked. It should be considered that the lack of oral hygiene may cause complications. In this review, information on the relationship between orthodontic treatment and oral flora is summarized. Asian J. Med. Biol. Res. 2022, 8 (4), 181-186

Awareness about the significance of acid-base balance of saliva in maintaining oral health.

Saliva is a multilayered secretion. The quality of saliva is just as crucial as the quantity. Saliva is necessary for preserving the integrity of oral structures, personal connections, digestion, and acid-base balance. The acid-base balance in one's oral environment is always being challenged. It happens every time we eat a meal, and when microorganisms are present. At a pH of 5 or 5.5, the demineralization of the enamel and hard tooth structures occurs. This study aimed to raise awareness about the importance of acid-base balance of saliva in dental health. A self-structured questionnaire was prepared to assess the awareness on the importance of acid-base balance in maintaining oral health. The questionnaire consisted of 20 questions, and the results were plotted in a graph. The Chi-square test was employed for evaluating the data, which was done with SPSS software. The study indicated that 91.74% of the participants were aware of the salivary pH in case of healthy gingiva, 34.82% of the respondents were aware of the salivary pH in case of chronic gingivitis, and 20.33% of the respondents were aware of the salivary pH in case of chronic periodontitis. We also correlated our results with gender and year of study. Oral health plays a major role in identifying systemic diseases and hence enough knowledge about various aspects about the oral cavity and its manifestations needs to be created among dental students to ensure that they become efficient dental surgeons in the future. Even though a fair amount of people knew the pH of clinically healthy gingiva, most of them did not know the pH at which periodontitis or gingivitis was caused. Hence, creating awareness about this topic stands vital. Further studies are required for a better understanding of salivary components and how they affect the caries process. The utilization of modified oral molecules as medicinal agents could become a reality with this understanding. Our findings imply that being aware of dietary composition has an impact on acid-base balance. To maintain the correct acid-base balance, more awareness of protein consumption is required.

Assessment of independent variables of periodontal disease among selected South Indian population.

Periodontal diseases are chronic diseases that affect the surrounding tissues of the teeth and the alveolar bone. As the disease progresses, it can lead to tooth loss. Several risk factors may increase the risk of periodontal disease. The objective of the study was to assess the independent variables of periodontal disease among the few of the Southern population of India. The current study was done on 155 patients who visited Saveetha Dental College and Hospitals. Data of demographic details (age, gender, educational status) and periodontal status (clinically healthy gingiva, gingivitis, and periodontitis) were recorded. The demographic and the periodontal parameters were associated using Chi-square test (SPSS Software, Version 23.0). 20-30-year-old patients were mostly affected with gingivitis (25.8%) and 51-60-year-old patients were affected with periodontitis (22.58%). This showed statistical significance (P < 0.05). More males were affected with periodontal diseases than females and were statistically insignificant (P > 0.05). Periodontitis was more common among illiterates (26.45%) and was statistically significant (P < 0.05). The study shows that periodontitis was predominantly seen among males of 51-60 years of age and illiterates. The results of the study reveal a positive association between age, gender, and educational status of patients with their periodontal health.

Tissue Levels of CD80, CD163 and CD206 and Their Ratios in Periodontal and Peri-Implant Health and Disease.

This study aimed to compare tissue levels of CD80 (pro-inflammatory macrophage-related surface marker), CD163, and CD206 (anti-inflammatory macrophage-related surface markers), and their ratios in periodontal and peri-implant health and disease. Altogether, 36 tissue samples were obtained from 36 participants with clinically healthy gingiva (n = 10), healthy peri-implant mucosa (n = 8), periodontitis lesions (n = 9), and peri-implantitis lesions (n = 9). CD80, CD163, and CD206 levels were assessed with immunoblotting. CD163 levels were found to be decreased (p = 0.004), and the CD80/CD163 ratio was found to be elevated (p = 0.002) in periodontitis lesions compared to healthy gingiva. Peri-implantitis lesions showed a tendency towards a higher CD80/CD163 ratio than in healthy peri-implant mucosa with a borderline difference (p = 0.054). No statistically significant difference was detected in CD80, CD163, and CD206 levels of periodontitis lesions when compared to peri-implantitis, and in healthy gingiva when compared to healthy peri-implant mucosa. A disruption in CD80/CD163 balance seems to be related to the pathogenesis of periodontitis and peri-implantitis, being less prominent in the latter. The reason behind this phenomenon may be either suppressed CD163 expression or reduced CD163+ anti-inflammatory macrophage abundance.

Novel Correlations among the Histopathological Components of Oral Squamous Cell Carcinoma

Background: Oral squamous cell carcinoma (OSCC) is an aggressive tumor with high mortality and morbidity rates.&#x0D; Aims:In this study, we aimed to probe whether there is association between stromal histopathological parameters with patient data, as well as, the correlation of these parameters with each other.&#x0D; MaterialsandMethods:This study was performed at University of Duhok, College of Dentistry, the practical section was carried out between February 2022 and June 2022 as follow:A group of 86 formalin fixed paraffin embedded (FFPE) samples of OSCC and 20 FFPE samplesof healthy gingiva were stained with Hematoxylin and eosin(H&amp;E) and Mason’s trichrome (MT)stains. Tumor/ stroma ratio(TSR), stromal tumor-infiltrating lymphocytes(sTIL), budding activity (BA), cell nest size (CNS), orientation and packing of collagen fibers and collagen fibercontent(CFC) were evaluated. These histomorphological parameters were correlated with clinicopathological characteristics and with each other.&#x0D; Statistical Analysis Used: Chi square test, fisher exacts test and spearman’s rank correlation coefficient were used for analyzing our study data.&#x0D; Results: Tumor/ stroma ratio, BA, CNS, orientation and packing of collagen fibers, and CFC were significantly associated with pT stage of the tumor. Moreover, significant correlations were observed among TSR, BA, CNS and CFC. In addition, orientation and packing of collagen fibers were significantly correlated with each other.&#x0D; Conclusions: Novel correlations were found between collagen fiber features with TSR, BA, and CNS in an easy and cost- effective methods.

Viabilty Test of Fish Scales Collagen Gourami (Oshpronemus Gouramy) on Human Gingival Fibroblasts Cells

Periodontal disease is a pathological inflammatory condition of the periodontal tissues surrounding the teeth, including Human Gingival Fibroblasts (HGF) which is one of the major components of tissue formation in periodonsium. HGF regeneration with the accelerating proliferation of tissue engineering therapy needs. Generally, the tissue engineering using regenerative materials from cow or pig as the therapies, but these materials have some flaws so this research to find alternative materials regenerative tissue engineering scaffold collagen type 1 derived from fresh water fish scales, one of which are gourami fish scales. This research was conducted to test the viability of fish scales collagen gouramy against Human Gingival Fibroblasts for 24 hours. This study aimed to determine the concentration of fish scale collagen gourami which can maintain the viability of human gingival fibroblast cells for 24 hours. HGF is taken from healthy gingiva and planted in 96 well plates. Fish scales collagen gouramy with a concentration of 0.32 mg/ml, 0.16 mg/ml, 0.04 mg/ml, 0.02 mg/ml and 0.01 mg/ml were added to each well and incubated during 24 hours. MTT Assay is performed to see the viability of fibroblast cells. The viability of HGF were increased after the addition of fish scales collagen gourami on concentration 0.32 mg/ml until 0.01 mg/ml. The highest viability of the cells was shown after the addition of 0.01 mg/ml. Fish scales collagen gouramy has the potential in tissue engeneering and the concentration of 0.01 mg/ml shows the highest viability of HGF.

Immunoexpression of interferon-gamma in the interdental gingiva of chronic periodontitis patients with interferon-gamma (+874A/T) rs62559044 polymorphism.

Interferon-gamma (IFNγ), which is involved in inflammation, has an essential role in the pathogenesis of chronic periodontitis (CP). The association of IFNγ +874A/T gene polymorphisms with a higher incidence of CP has been reported previously. We investigated the immunoexpression of IFNγ in human gingiva from CP patients with IFNγ +874A/T gene polymorphisms compared to a healthy group. Biopsies from interdental gingiva (n=60) were obtained from CP patients (n=38) and individuals who had clinically healthy gingiva (n=22). The specimens were classified according to genotypes of IFNγ +874A/T gene polymorphism using amplification-refractory mutation system-polymerase chain reaction (ARMS-PCR) (10AA, 18AT, and 10TT). After tissue processing and slide preparation, we evaluated the expression levels of IFNγ in the interdental gingiva using the immunohistochemistry technique. Values were compared between two study groups by Mann-Whitney and Kruskal-Wallis analysis. P<0.05 was considered the level of significance. There was a noticeable increase in the immunoexpression of IFNγ in the gingival epithelium, fibroblasts, and capillaries of gingival tissue from CP patients compared to the control group. We found different levels of IFNγ expression in different parts of the gingival epithelium. The highest levels were found in the middle regions of the gingival epithelium in patients with TT genotypes. Immune cells and vascular endothelium of gingiva in the AA group also showed increased expression of IFNγ. Results suggest that IFNγ +874A/T gene polymorphism may change the expression level of IFNγ and subsequently the progression of CP.

Immunohistochemical differential expression of p16 proteins in follicular type and plexiform type ameloblastoma

Background: Differences in histopathological features that describe the growth mechanism and biological behaviour of follicular and plexiform ameloblastomas are associated with benign, aggressive and destructive tumour markers. p16 has inhibitory interactions between cyclin D and CDK 4/6 to block the cell cycle and alterations related to severity. Purpose: This study intends to evaluate and determine differential expressions of p16 protein in follicular and plexiform ameloblastomas. Methods: This is a descriptive analytics study. A total of 21 specimens consisting of follicular and plexiform ameloblastomas and healthy gingiva tissues as the negative control were examined using the immunohistochemistry assay. The analysis of p16 protein expression was interpreted by immunoreactive scoring. Statistical analysis was conducted using SPSS software with the Mann–Whitney test. A p-value &lt;0.05 shows the significance of the change in expression. Results: An increased expression of p16 protein was found in the follicular ameloblastoma type (2.13 ± 1.808) and the plexiform type (4.44 ± 2.506) in comparison to the negative control group (0 ± 0). The increase of p16 expression in the follicular and plexiform ameloblastomas was significant compared to the negative control group (p-value &lt;0.05); however, there was no significant difference between either type of ameloblastoma (p-value &gt;0.05). Conclusion: The highest intensity of p16 protein expression was found in the plexiform type, even though it was not significantly different from the follicular type ameloblastoma.

Whole-transcriptome analysis of periodontal tissue and construction of immune-related competitive endogenous RNA network

BackgroundIn periodontitis, noncoding RNAs may play a regulatory role in the immune microenvironment through competitive endogenous RNA. We aimed to profile noncoding RNA expression and construct immune-related ceRNA network in periodontitis.MethodsFive inflamed periodontal tissue and five healthy gingivae were collected for whole-transcriptome sequencing. Differential gene, functional enrichment, and protein–protein interaction network analysis were performed to explore the function of differentially expressed genes. CIBERSORTx was used to analyze level of immune cell infiltration in the periodontal tissue. An immune-related competitive endogenous RNA network was constructed and expression of key regulators in the network was validated.ResultsCompared with healthy gingiva, 200 mRNAs, 90 long noncoding RNAs, 65 microRNAs, and 518 circular RNAs were differentially expressed, and cell chemotaxis was significantly enhanced in inflamed periodontal tissue. Immune cell infiltration analysis showed that neutrophils, macrophages M1, T follicular helper cells, and naive B cells were significantly increased in periodontitis. Key regulators including JUN, FOS, THBS1, KLF2, WIF1, were identified and their expression was then validated.ConclusionWe constructed an immune-related competitive endogenous RNA network in periodontal tissue, which provided new insights into immune homeostasis in periodontitis and laid a foundation for further study of noncoding RNAs. Key regulators in this network may be promising targets for future periodontitis treatment.

The Viability of Collagen Peptide from Osphronemus goramy Fish Scale Extract on Human Gingival Fibroblast

Background: Damage to the periodontium tissue requires a regenerative treatment to increase the dimensions of the lost bone. This research was conducted to find another regenerative material with the use of type 1 collagen peptides derived from gourami fish scales. This study was conducted to test the viability of gourami scales collagen peptides on Human Gingival Fibroblast cells for 24 hours. Purpose: To determine the viability of Human Gingival Fibroblasts (HGF) after the administration of collagen peptides of gourami fish scales. Method: HGF was taken from healthy gingiva and planted in 96 well plates. The type 1 collagen peptides of gourami fish scales with concentrations of 0.32 mg / ml, 0.16 mg / ml, 0.04 mg / ml, 0.02 mg / ml and 0.01 mg / ml were inserted into each well and incubated for 24 hours. MTT Assay was performed to see the viability of fibroblast cells. Results: There was an increase in the viability value from a concentration of 0.32 mg/ml to 0.01 mg/ml. The concentration of 0.01 mg/ml showed the highest viability. Conclusion: The collagen peptide is a potential substance for tissue engineering. The concentration of 0.01 mg/ml collagen peptides shows the highest HGF viability.

Comparative Evaluation of Gingival Crevicular Fluid Interleukin-17, 18 and 21 in Different Stages of Periodontal Health and Disease.

Background and Objectives: The elicitation of a host’s immune–inflammatory responses to overcome oral bacterial biofilm challenges is mediated by numerous cytokines. We explored the role of three such cytokines, viz. interleukin (IL)-17, 18 and 21, by measuring their levels in the gingival crevicular fluid (GCF) of Indian individuals with healthy gingiva, chronic gingivitis, or chronic periodontitis. Materials and Method: Ninety systemically healthy individuals were enrolled in the study on the basis of predefined criteria and were categorized into three groups of 30 participants each. Groups A, B and C were composed of a control group with healthy gingiva, subjects with chronic gingivitis and subjects with chronic periodontitis, respectively. The periodontal disease status was assessed on the basis of a subject’s gingival index, probing pocket depth, clinical attachment loss and radiographic evidence of bone loss. After the complete history-taking and identification of gingival sulcus/pocket depth areas for GCF collection, a sample was collected from each subject in all groups for an estimation of the cytokine levels using ELISA. Statistical analysis was performed using SPSS v 21.0. Intergroup comparisons were conducted using a post hoc Tukey’s test. A value of p < 0.05 was considered to be statistically significant. Results: The mean IL-17, 18 and 21 concentrations in pg/mL was the greatest for Group C (99.67 ± 18.85, 144.61 ± 20.83 and 69.67 ± 12.46, respectively), followed by Group B (19.27 ± 2.78, 22.27 ± 2.43 and 22.74 ± 1.43, respectively) and finally by Group A (healthy control; 11.56 ± 0.99, 17.94 ± 1.24 and 12.83 ± 1.21 respectively). A statistically significant difference in the mean concentrations of two interleukins (IL-17 and IL-18) was observed between Groups A and C and also between Groups B and C. A statistically significant difference in the mean concentrations of IL-21 was observed between Groups B and C. Conclusions: Within the limitations of the present study, the findings revealed that the GCF levels of IL-17, IL-18 and IL-21 rose and correlated well with the severity of the disease. Thus, these cytokines present in GCF have the potential to be considered as biomarkers for periodontal tissue destruction. IL-21 in particular appears to be a promising biomarker for differentiating between gingivitis and periodontitis.

The Effect of Changing the Toothbrush on the Marginal Gingiva Microcirculation in the Adolescent Population-A Laser Doppler Flowmetry Assessment.

It is well-known that proper tooth brushing has the effect of stimulating microcirculation in a healthy gingiva. The aim of this study was to evaluate the microcirculation dynamics at the level of healthy marginal gingiva in adolescents after changing their toothbrush. Three evaluation instruments were employed to assess and quantify the effects on the marginal gingiva: the periodontal probing depth (PD), gingival index (GI) and laser Doppler flowmetry (LDF). A total of 12 adolescents, aged between 15 and 20, were enrolled in the study, resulting in a total of 72 frontal upper teeth for PD and GI and 48 gingival interdental sites for LDF assessment. For each measurement, the pulp blood flow signal was recorded for 1 min and represented as a pulsatory signal. Data were collected in four moments: before the toothbrush changed and 24 h, 7 days and 14 days after. For the statistical analysis, the nonparametric Friedman test was applied for comparisons between more than two pair numeric series and for comparisons between two sets of pair values without Gaussian distribution, the Wilcoxon signed-rank test was applied. The paired t test was used for two sets of normally distributed paired values. The results showed that using a new toothbrush in the adolescent population with healthy gingiva can induce statistically significant increases in gingival blood flow, which remain at a high level even at two weeks. The GI also increases significantly at 7 days and 14 days, while the periodontal PD does not change significantly.

In vivo evaluation of traumatic and malignant oral ulcers with optical coherence tomography: A comparison between histopathological and ultrastructural findings

Ulcers in the oral mucosa is a relatively common, although challenging, entity in oral medicine, as it can arise due to a wide range of traumatic, infective, autoimmune, and neoplastic disorders. Although histopathology of lesional and peri‑lesional tissues remains the gold standard for persistent oral breaching, optical coherence tomography (OCT) has been recently suggested as a potential ally to enhance the early or non-invasive diagnosis of likely causation. The aim of the present study was to provide an in-vivo OCT analysis and description from a sample of 70 patients affected by traumatic or neoplastic-related ulcers, located on the buccal mucosa, tongue or gingiva, and compare the OCT data with those of 20 patients with healthy oral mucosa. OCT dynamic scans revealed clear distinction of epithelial layer (EP), lamina propria (LP) of healthy buccal mucosa, gingiva, and tongue as well as allowing observation of the keratin layer in gingiva, and the subepithelial vascularization of each site. Traumatic lesions had an EP of reduced in thickness, with an irregular, if not disrupted surface. Interestingly, LP seemed to preserve its reflectiveness and vascularization only in the traumatic lesions. Among neoplastic lesions, regardless their site of onset, both EP integrity/homogeneity, and LP reflectiveness/vascularization were lost and unrecognizable when compared to their healthy counterparts. OCT scanning allowed some differentiation between traumatic and malignant ulcers and thus may a useful and non-invasive means of determining the need and/or urgency of histopathological examination of oral lesions.

PINK1-mediated mitophagy reduced inflammatory responses to Porphyromonas gingivalis in macrophages.

Mitochondria are strained by microbial stimuli in the periodontal niche. Damaged mitochondria are cleared by mitophagy. The purpose of the study was to explore whether mitophagy participated in the progress of periodontitis and whether activation of mitophagy can inhibit inflammatory responses to bacterial infection in macrophages. Mitophagy-related genes were measured in the healthy and inflamed human gingiva. Bone marrow-derived macrophages (BMDMs) were infected with Porphyromonas gingivalis. Dexmedetomidine, urolithin A, and resveratrol were used to activate mitophagy, while small interference RNA was utilized to knock down PTEN-induced putative protein kinase 1 (PINK1). Activation of mitophagy-related genes and colocalization of them were detected by Western blot and confocal imaging. Damages of mitochondria, accumulation of mitochondrial reactive oxygen species (mtROS), and production of IL-1β, IL-6, and TNF-α were measured. Levels of mitophagy-related genes were decreased in inflamed periodontal tissues and P.gingivalis-infected BMDMs. Dexmedetomidine, urolithin A, and resveratrol activated mitophagy, leading to reduced mitochondria damages, decreased mtROS generation, and inhibited IL-1β, IL-6, and TNF-α production. PINK1 knockdown reduced dexmedetomidine, urolithin A, and resveratrol-induced anti-inflammatory effect. Inhibited mitophagy participated in the progress of periodontitis. Activation of mitophagy may become a therapeutic target during the progress of periodontitis by reducing mtROS.