MicroRNA-181b-5p modulates tumor necrosis factor-α-induced inflammatory responses by targeting interleukin-6 in cementoblasts.

Tooth cementum is a bone-like mineralized tissue and serves as a microbial barrier against invasion and destruction. Cementum is also responsible for tooth stability and defending pulp from outside stimuli, which is formed by cementoblasts. Although it is crucial for periodontal and periapical diseases, the mechanisms underlying the pathophysiological changes of cementoblasts and their inflammatory responses remain unclear. MiR-181b is found to modulate vascular inflammation and endotoxin tolerance. In this study, miR-181b-5p was downregulated in tumor necrosis factor-α (TNF-α)-stimulated cementoblasts, whereas proinflammatory molecules increased. The mouse periapical lesions have similar results, which imitate an inflammatory environment for cementoblasts in vivo. The bioinformatics analysis and dual luciferase reporter assay suggested that miR-181b-5p targeted interleukin-6 (IL-6). Overexpressing miR-181b-5p negatively regulated IL-6 and proinflammatory chemokine. Western blot analysis and luciferase activity reporter assay verified that miR-181b-5p weakened the NF-κB activity. Hence, miR-181b-5p moderated proinflammatory chemokine production by targeting IL-6 in cementoblasts and NF-κB signaling pathway was involved. Furthermore, miR-181b-5p promoted cementoblast apoptosis, which may enhance the resolution of inflammation. Overall, our data revealed that miR-181b-5p was a negative regulator of TNF-α-induced inflammatory responses in cementoblasts.

Penetration and bactericidal efficacy of two oral care products in an oral biofilm model.

PURPOSE: To investigate the immediate penetration and bactericidal effect of two oral care products marketed in China on an intact natural plaque biofilm model at different time points. METHODS: Eight subjects (aged 20 to 30 years; Turesky Plaque Index Score 2 to 3) were enrolled in the study according to the inclusion criteria. Plaque accumulators were worn by the subjects for 6 and 48 hours for harvesting the dental biofilm. Then the biofilms from different groups were stained with the LIVE/DEAD BacLight fluorescence system to investigate the changes in thickness and fluorescence intensity of living bacteria in biofilm 5 and 15 minutes post-treatment with a mouthrinse containing 0.074% cetylpyridinium chloride (1-minute treatment) or a toothpaste supernatant containing 1.16% stannous chloride (2-minute treatment). In addition, a specific Sn2+ probe was utilized to evaluate the penetration of Sn2+ in the biofilm. Fluorescent images were collected using confocal laser scanning microscopy. Analysis of covariance was used for statistical analyses. All comparisons were two-sided using a 5% level of significance. RESULTS: The thickness of generated plaque biofilm increased gradually from 7.352±4.22 µm at 6 hours to 16.73±7.38 µm at 48 hours (P< 0.05), whereas the thickness and fluorescence intensity of living bacteria stayed unchanged over time. After the treatment of toothpaste supernatant, the ratios of living bacteria thickness and fluorescence intensity of 6- and 48-hour plaque biofilm were significantly decreased (P< 0.05). Treatment of mouthrinse reduced the ratio of living bacteria thickness, but showed no significant impact on overall fluorescence intensity of living bacteria. For 48-hour biofilm, toothpaste supernatant significantly reduced fluorescence intensity of living bacteria from outer layer through inner layer, whereas the mouthrinse showed bactericidal effect only in the outer layer and middle layer. A wide distribution of Sn2+ was shown in the biofilm with the treatment of the tested toothpaste. CLINICAL SIGNIFICANCE: This biofilm model proved to be useful and appropriate for pre-clinical testing of anti-plaque agents. A brief exposure of the biofilm to the tested toothpaste produced significant losses in bacteria viability across outer-middle-inner layers. The tested mouthrinse exerted its bactericidal effect mostly in outer and middle layers of biofilm. The penetration of Sn2+ in the biofilm performed an important function in the bactericidal effect of the toothpaste.

A cuttlefish ink nanoparticle-reinforced biopolymer hydrogel with robust adhesive and immunomodulatory features for treating oral ulcers in diabetes.

Oral ulcers can be managed using a variety of biomaterials that deliver drugs or cytokines. However, many patients experience minimal benefits from certain medical treatments because of poor compliance, short retention times in the oral cavity, and inadequate drug efficacy. Herein, we present a novel hydrogel patch (SCE2) composed of a biopolymer matrix (featuring ultraviolet-triggered adhesion properties) loaded with cuttlefish ink nanoparticles (possessing pro-healing functions). Applying a straightforward local method initiates the formation of a hydrogel barrier that adheres to mucosal injuries under the influence of ultraviolet light. SCE2 then demonstrates exceptional capabilities for near-infrared photothermal sterilization and neutralization of reactive oxygen species. These properties contribute to the elimination of bacteria and the management of the oxidation process, thus accelerating the healing phase's progression from inflammation to proliferation. In studies involving diabetic rats with oral ulcers, the SCE2 adhesive patch significantly quickens recovery by altering the inflamed state of the injured area, facilitating rapid re-epithelialization, and fostering angiogenesis. In conclusion, this light-sensitive hydrogel patch offers a promising path to expedited wound healing, potentially transforming treatment strategies for clinical oral ulcers.

Cementodentinal Tear Associated with a Periodontal- Endodontic Combined Lesion: A Case Report with a 14-Month Follow-up.

This case report describes the diagnosis and multidisciplinary treatment of a clinically indiscoverable cementodentinal tear associated with a periodontal-endodontic combined lesion. The tear site was located at the palatal root surface of the maxillary left canine. Due to its position and concomitant periapical periodontitis, it was not noticed at the initial visit until a 3D CBCT examination was conducted. Through combined endodontic-periodontal therapy (which included root canal therapy, root debridement, and periodontal flap surgery), the tear fragment was removed, and the periapical lesion healed gradually. A histologic examination confirmed the definitive diagnosis of a cementodentinal tear. After 14 months, the periodontal and endodontic status of the maxillary left canine were stable. According to these results, CBCT examination and multidisciplinary cooperation seem to be effective and necessary for the diagnosis and treatment of such clinically indiscoverable cementodentinal/cemental tears.

Cyclophilin A (CypA) is associated with the inflammatory infiltration and alveolar bone destruction in an experimental periodontitis.

BACKGROUND AND OBJECTIVE: CypA is able to regulate inflammatory responses and MMPs production via interaction with its cell surface receptor, EMMPRIN. This study aimed to address the possible association of CypA with pathological inflammation and destruction of periodontal tissues, and whether CypA-EMMPRIN interaction exists in periodontitis. MATERIALS AND METHODS: Experimental periodontitis was induced by ligation according to our previous method. Histological and radiographic examinations were performed. Western blot was used to detect CypA and EMMPRIN expressions in gingival tissues. Immunohistochemistry was applied for CypA, EMMPRIN, MMP-1, MMP-2, MMP-9, as well as cell markers of macrophage, lymphocyte and neutrophil. CypA expression, alveolar bone loss, and inflammatory infiltrations were quantified followed by correlation analyses. RESULTS: Western blot revealed that CypA and EMMRPIN expressions were dramatically elevated in inflamed gingival tissues (ligature group) as compared to healthy gingival tissues (control group). The enhanced CypA and EMMPRIN expressions were highly consistent in cell localization on seriate sections. They were permanently co-localized in infiltrating macrophages and lymphocytes, as well as osteoclasts and osteoblasts in interradicular bone, but rarely expressed by infiltrating neutrophils. MMP-1, MMP-2, and MMP-9 expressions were also sharply increased in inflamed gingiva. MMP-2 and MMP-9 were mainly over-expressed by macrophages, while MMP-1 was over-produced by fibroblasts and infiltrating cells. The number of CypA-positive cells was strongly correlated with the ACJ-AC distance (r=0.839, p=0.000), the number of macrophages (r=0.972, p=0.000), and the number of lymphocytes (r=0.951, p=0.000). CONCLUSION: CypA is associated with the inflammatory infiltration and alveolar bone destruction of periodontitis. CypA-EMMPRIN interaction may exist in these pathological processes.

MicroRNA-212-5p regulates the inflammatory response of periodontal ligament cells by targeting myeloid differentiation factor 88.

OBJECTIVE: This study was aimed to investigate the effects of microRNA-212-5p (miR-212-5p) and myeloid differentiation factor 88 (Myd88) in Porphyromonas gingivalis lipopolysaccharide (P. gingivalis LPS)-challenged human periodontal ligament cells (PDLCs). METHODS: The levels of miR-212-5p and Myd88 in PDLCs were determined via quantitative real-time Polymerase Chain Reaction. Cell viability and pro-inflammatory cytokines were assessed using MTT assay and enzyme-linked immunosorbent assay. Bioinformatics and luciferase reporter gene assay were employed to explore the interaction between miR-212-5p and Myd88. Moreover, the activation of p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B signal pathways were testified via western blot analysis. RESULTS: MiR-212-5p was downregulated following stimulation of P. gingivalis LPS. Overexpression of miR-212-5p elevated the cell viability and reduced the secretion of pro-inflammatory cytokines. Myd88 is a target of miR-212-5p. Notably, pcDNA3.1-Myd88 reversed the anti-inflammatory effect of miR-212-5p overexpression. Likewise, miR-212-5p mimic inhibited the activation of p38 MAPK and nuclear factor kappa-B, whereas pcDNA3.1-Myd88 abrogated the effect of miR-212-5p mimic. CONCLUSIONS: MiR-212-5p inhibited the inflammatory response in PDLCs by targeting Myd88, which may involve the inactivation of p38 MAPK and nuclear factor kappa-B.

The effect of the surgical microscope on the outcome of root scaling.

The benefits of using a surgical microscope in periodontal therapy were mainly based on subjective statements made by patients or periodontists. We aimed to provide laboratory evidence for the advantages of using a surgical microscope during root scaling on periodontitis teeth. In the present study, the extracted teeth were categorized into four groups: normal teeth (normal control [NC] group), untreated periodontitis teeth (periodontitis control [PC] group), root surface scaled without magnification (macro group), and root surface instrumented with a microscope (micro group). To analyze both the mechanical and biological properties of the root surfaces, we performed nanoindentation in addition to the traditional methods. We found that by using a surgical microscope, we improved the clearance of bacterial deposits and calculi on periodontitis root surfaces. Nanoindentation results revealed that the nanotopography pattern, elastic modulus, and nanohardness of the root surface in the micro group were closest to those in the NC group. The immunofluorescence assay and cell proliferation analyses revealed improved morphology and enhanced adhesion and proliferation of periodontal ligament cells on the root surface in the micro group compared with the macro group. After instrumentation, the expression levels of interleukin-6 and interleukin-8 decreased when compared with the PC group. Our results demonstrated that surgical microscope application could improve the outcomes of periodontal treatment, implying that a surgical microscope can be a powerful tool for periodontists to seek accurate clinical periodontal performance and gain better biocompatibility of the treated root surfaces.

A deep learning algorithm for detection of oral cavity squamous cell carcinoma from photographic images: A retrospective study.

BACKGROUND: The overall prognosis of oral cancer remains poor because over half of patients are diagnosed at advanced-stages. Previously reported screening and earlier detection methods for oral cancer still largely rely on health workers' clinical experience and as yet there is no established method. We aimed to develop a rapid, non-invasive, cost-effective, and easy-to-use deep learning approach for identifying oral cavity squamous cell carcinoma (OCSCC) patients using photographic images. METHODS: We developed an automated deep learning algorithm using cascaded convolutional neural networks to detect OCSCC from photographic images. We included all biopsy-proven OCSCC photographs and normal controls of 44,409 clinical images collected from 11 hospitals around China between April 12, 2006, and Nov 25, 2019. We trained the algorithm on a randomly selected part of this dataset (development dataset) and used the rest for testing (internal validation dataset). Additionally, we curated an external validation dataset comprising clinical photographs from six representative journals in the field of dentistry and oral surgery. We also compared the performance of the algorithm with that of seven oral cancer specialists on a clinical validation dataset. We used the pathological reports as gold standard for OCSCC identification. We evaluated the algorithm performance on the internal, external, and clinical validation datasets by calculating the area under the receiver operating characteristic curves (AUCs), accuracy, sensitivity, and specificity with two-sided 95% CIs. FINDINGS: 1469 intraoral photographic images were used to validate our approach. The deep learning algorithm achieved an AUC of 0·983 (95% CI 0·973-0·991), sensitivity of 94·9% (0·915-0·978), and specificity of 88·7% (0·845-0·926) on the internal validation dataset (n = 401), and an AUC of 0·935 (0·910-0·957), sensitivity of 89·6% (0·847-0·942) and specificity of 80·6% (0·757-0·853) on the external validation dataset (n = 402). For a secondary analysis on the internal validation dataset, the algorithm presented an AUC of 0·995 (0·988-0·999), sensitivity of 97·4% (0·932-1·000) and specificity of 93·5% (0·882-0·979) in detecting early-stage OCSCC. On the clinical validation dataset (n = 666), our algorithm achieved comparable performance to that of the average oral cancer expert in terms of accuracy (92·3% [0·902-0·943] vs 92.4% [0·912-0·936]), sensitivity (91·0% [0·879-0·941] vs 91·7% [0·898-0·934]), and specificity (93·5% [0·909-0·960] vs 93·1% [0·914-0·948]). The algorithm also achieved significantly better performance than that of the average medical student (accuracy of 87·0% [0·855-0·885], sensitivity of 83·1% [0·807-0·854], and specificity of 90·7% [0·889-0·924]) and the average non-medical student (accuracy of 77·2% [0·757-0·787], sensitivity of 76·6% [0·743-0·788], and specificity of 77·9% [0·759-0·797]). INTERPRETATION: Automated detection of OCSCC by deep-learning-powered algorithm is a rapid, non-invasive, low-cost, and convenient method, which yielded comparable performance to that of human specialists and has the potential to be used as a clinical tool for fast screening, earlier detection, and therapeutic efficacy assessment of the cancer.

A potential role of EMMPRIN by regulating ECM degradation in periodontitis.

Periodontitis are characterized by the destruction of the extracellular matrix (ECM) of periodontal tissues. Matrix metalloproteinases (MMPs) play an important role in the degradation of ECM. But until now, it is not clear about the regulation of MMPs expression level in periodontitis. EMMPRIN is a 58 kDa, highly glycosylated, transmembrane molecule belonging to the immunoglobin superfamily, which interacts with fibroblasts to stimulate the expression of MMPs. It is logical to postulate that EMMPRIN may play a critical role in the regulation of MMPs participating the destruction of periodontal ECM in periodontitis. The hypothesis will provide the brand-new direction that we may prevent and treat the periodontitis by regulating the expression of EMMPRIN in host aspect.

Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in healthy and inflamed human gingival.

OBJECTIVE: To evaluate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in healthy and inflamed human gingiva. METHOD AND MATERIALS: Tissue samples from 9 healthy specimens and 21 specimens with chronic periodontitis were collected. The expression of EMMPRIN protein was detected with immunohistochemical staining and Western blot analysis. RESULTS: EMMPRIN was mainly localized in keratinocytes of healthy human gingival tissues; in inflamed gingival tissues, EMMPRIN protein could be detected in keratinocytes, fibroblasts, and inflammatory cells. In addition, EMMPRIN expression level in the inflamed gingiva was increased dramatically compared to that in healthy tissue (P < .05). Using Western blot analysis, EMMPRIN protein was also found to express in both healthy and inflamed gingiva, and the level of EMMPRIN in inflamed gingiva was significantly higher than that in healthy control subjects (P < .05). CONCLUSION: EMMPRIN might be involved in the physiologic and pathologic states of periodontal tissues.