The role of periodontitis in cancer development, with a focus on oral cancers.

Periodontitis is a severe gum infection that begins as gingivitis and can lead to gum recession, bone loss, and tooth loss if left untreated. It is primarily caused by bacterial infection, which triggers inflammation and the formation of periodontal pockets. Notably, periodontitis is associated with systemic health issues and has been linked to heart disease, diabetes, respiratory diseases, adverse pregnancy outcomes, and cancers. Accordingly, the presence of chronic inflammation and immune system dysregulation in individuals with periodontitis significantly contributes to the initiation and progression of various cancers, particularly oral cancers. These processes promote genetic mutations, impair DNA repair mechanisms, and create a tumor-supportive environment. Moreover, the bacteria associated with periodontitis produce harmful byproducts and toxins that directly damage the DNA within oral cells, exacerbating cancer development. In addition, chronic inflammation not only stimulates cell proliferation but also inhibits apoptosis, causes DNA damage, and triggers the release of pro-inflammatory cytokines. Collectively, these factors play a crucial role in the progression of cancer in individuals affected by periodontitis. Further, specific viral and bacterial agents, such as hepatitis B and C viruses, human papillomavirus (HPV), Helicobacter pylori (H. pylori), and Porphyromonas gingivalis, contribute to cancer development through distinct mechanisms. Bacterial infections have systemic implications for cancer development, while viral infections provoke immune and inflammatory responses that can lead to genetic mutations. This review will elucidate the link between periodontitis and cancers, particularly oral cancers, exploring their underlying mechanisms to provide insights for future research and treatment advancements.

Thymoquinone potentiates anti-cancer effects of cisplatin in oral squamous cell carcinoma via targeting oxidative stress.

Recent evidence has proved that thymoquinone as a natural polyphenol has great anticancer and anti-proliferative effects in cancer cells. In this study, we aimed to examine the effects of thymoquinone on increasing cisplatin-induced apoptosis human oral squamous cell carcinoma cells and its underlying molecular mechanisms. SCC-25 cancer cells treated by thymoquinone and cisplatin with different concentrations. Cell viability will determine by using MTT assay. The concentrations of reactive oxygen species (ROS) and antioxidant activities were determined using specific related kits. DNA damage, lipid, and protein oxidation were assessed. Real-time PCR and Western blot analysis will be used to determine the expression of apoptosis-related proteins including Bax, Bcl-2, and caspase-3. Combination of thymoquinone and cisplatin suppressed synergistically SCC-25 cancer cell viability and induced apoptosis in dose-depended manner. Cell treatment with combination of thymoquinone and cisplatin led to accumulation of ROS within cells and increase in the intracellular levels of DNA damage, protein and lipid peroxidation. In addition, the combination of thymoquinone and cisplatin modulated the mRNA and protein expression levels of apoptosis-related proteins including Bax, Bcl-2, and caspase-3. Thymoquinone potentiated cisplatin anti-cancer effect on OSCC by inducing oxidative stress in cells.

Recent Approaches to Enhance Osteogenesis of Dental Pulp Stem Cells on Electrospun Scaffolds.

Critical-sized bone defects are a challenging issue during bone regeneration. Bone tissue engineering is aimed to repair such defects using biomimicking scaffolds and stem cells. Electrospinning allows the fabrication of biocompatible, biodegradable, and strengthened scaffolds for bone regeneration. Natural and synthetic polymers, alone or in combination, have been employed to fabricate scaffolds with appropriate properties for the osteogenic differentiation of stem cells. Dental pulps are rich in stem cells, and dental pulp stem cells (DPSCs) have a high capacity for proliferation, differentiation, immunomodulation, and trophic factor expression. Researchers have tried to enhance osteogenesis through scaffold modification approaches, including incorporation or coating with mineral, inorganic materials, and herbal extract components. Among them, the incorporation of nanofibers with hyaluronic acid (HA) has been widely used to promote osteogenesis. In this review, the electrospun scaffolds and their modifications used in combination with DPSCs for bone regeneration are discussed.

MiR-34 by targeting p53 induces apoptosis and DNA damage in paclitaxel-resistant human oral squamous carcinoma cells.

MicroRNA-34 (miR-34) is one the most important tumor suppressor miRNAs involving in the various aspects of oral cancer. The present study aimed to evaluate the effects of miR-34 restoration in OECM-1 oral cancer resistant to paclitaxel (OECM-1/PTX) and its underlying mechanisms through p53-mediated DNA damage and apoptosis. OECM-1 and OECM-1/PTX were transfected with miR-34 mimic and inhibitor. Cellular proliferation and apoptosis were evaluated through MTT assay and flow cytometry, respectively. The mRNA and protein expression levels of p53, p-glycoprotein (P-gp), ATM, ATR, CHK1, and CHK2 were assessed through qRT-PCR and western blotting. Rhodamin123 uptake assay was used to measure the P-gp activities. P53 expression was also suppressed by sing a siRNA transfection of cells. The expression levels of miR-34 were downregulated in OECM-1/PTX. Restoration of miR-34 led to increase in cytotoxic effects of paclitaxel in cells. In addition, the expression levels and activities of P-gp were reduced following miR-34 transfection. miR-34 transfection upregulated the p53, ATM, ATR, CHK1, and CHK2 expression levels in OECM-1/PTX cells. Furthermore, cells transfected with miR-34 showed higher levels of apoptosis. miR-34 restoration reverses paclitaxel resistance in OECM-1 oral cancer. The chemosensitive effects of miR-34 is mediated through increasing DNA damage and apoptosis in a p53 depended manner.

Potential applications of medicinal herbs and phytochemicals in oral and dental health: Status quo and future perspectives.

OBJECTIVE: Herbal therapies are utilized to treat a broad diversity of diseases all over the globe. Although no clinical studies have been conducted to demonstrate the antibacterial, antimicrobial, and antiplaque characteristics of these plants, this does not imply that they are ineffectual as periodontal treatments or anti-cariogenic drugs. However, there is a scarcity of research confirming their efficacy and worth. SUBJECT: Herbs are utilized in dentistry as antimicrobial, antineoplastic, antiseptic, antioxidant, and analgesics agents as well as for the elimination of bad breath. In addition, the application of herbal agents in tissue engineering improved the regeneration of oral and dental tissues. This study reviews the application of medicinal herbs for the treatment of dental and oral diseases in different aspects. METHODS: This article focuses on current developments in the use of medicinal herbs and phytochemicals in oral and dental health. An extensive literature review was conducted via an Internet database, mostly PubMed. The articles included full-text publications written in English without any restrictions on a date. CONCLUSION: Plants have been suggested, as an alternate remedy for oral-dental problems, and this vocation needs long-term dependability. More research on herbal medicine potential as pharmaceutical sources and/or therapies is needed.

Effect of immersion in sodium hypochlorite on cyclic fatigue resistance of RaCe, HyFlex CM and XP-endo shaper files.

Background: This study assessed the effect of sodium hypochlorite on cyclic fatigue resistance of RaCe, HyFlex CM and XP-endo Shaper files. Materials and Methods: In this in vitro, experimental study, 90 RaCe, HyFlex CM and XP-endo Shaper files (n = 30 of each) were divided into two groups (n = 45). Group 1 included 15 files of each rotary system, which were immersed in 37°C sodium hypochlorite (5.25%) for 5 min. Group 2 files were immersed in 37°C saline for 5 min. The files underwent cyclic fatigue testing using simulated root canals in which, the rotary files could freely rotate until fracture. Time of fracture was recorded by a chronometer and the number of cycles until fracture was calculated. Data were analyzed using two-way ANOVA and Bonferroni test (α = 0.05). Results: No significant difference existed in the mean number of cycles or rotation time of files between saline and sodium hypochlorite (P > 0.05). The mean rotation time of RaCe was significantly shorter than that of HyFlex and XP-endo Shaper in both solutions (P < 0.05). The mean number of cycles of RaCe was significantly lower than that of HyFlex and XP-endo Shaper files in both solutions (P < 0.05). The mean number of cycles of HyFlex was significantly lower than that of XP-endo Shaper (P < 0.05). >Conclusion: Immersion of rotary files made of different alloys in 5.25% sodium hypochlorite for 5 min had no effect on their fracture resistance. However, type of file alloy affected its fatigue resistance such that XP-endo Shaper showed the highest and RaCe showed the lowest fatigue resistance.

The expression of salivary microRNAs in oral lichen planus: Searching for a prognostic biomarker.

Oral lichen planus (OLP) is a premalignant disease with unknown etiology. It has been demonstrated that inflammation and immune activation play a central role in the pathogenesis of OLP. Various cellular and molecular mechanisms are involved in the pathogenesis of OLP. Studies have shown that 2-7% of OLP patients develop oral squamous cell carcinoma (OSCC). As a result, determining the prognosis of the disease will be promising in preventing oral carcinoma. MicroRNAs are involved in the regulation of cytokine expression and cytokines have a central role in the pathogenesis of OLP. As a result, their evaluation in body fluids may be helpful in assessing the disease's status and progression, and facilitating the treatment process. In this regard, much attention has been paid to the saliva of OLP patients as the sampling is cost-effective and non-invasive. Here, we discuss the potential of miRNAs in predicting the disease severity and progression.

Pattern of maxillofacial fractures: a 5-year analysis of 8,818 patients.

BACKGROUND: This multicenter study assessed the demographics, prevalence, causes, types, treatment, and complications of maxillofacial (MF) fractures managed by MF surgeons nationwide. METHODS: This 5-year retrospective descriptive analytical chart study evaluated 8,818 patients treated for MF fractures from 2007 to 2012 at 11 medical centers. Parameters, including age, sex, cause of injury, site of injury, type of injury, fracture patterns, treatment modalities, and complications, were evaluated from patient charts and radiographs. Collected data were analyzed via t test or χ test using SPSS 20 (Chicago, IL). A p value of less than 0.05 was considered statistically significant. This retrospective chart study was exempt from institutional review board approval. RESULTS: There were 7,369 male patients (83.6%), 1,376 female patients (15.7%), and 73 patients (0.8%) of unknown sex (aged 6 months to 112 years); 39.54% (3,457 patients) were in the 21-year to 30-year age group (mean, 28.18 years). We found 5,737 mandibular fractures (65.1%); mandible fracture was the most common (p < 0.05), followed by maxillary (1,641, 18.6%), zygomatic (3,240, 36.0%), orbital floor (743, 8.4%), naso-orbitoethmoidal (472, 5.4%), nasal (848, 9.6%), and frontal (344, 3.9%) fractures. Road traffic accidents were the most common cause. Posttreatment documented complications included remaining neurosensory disturbance of the inferior alveolar nerve (16.01%) and the infraorbital nerve (15.5%), remaining neuromotor disturbance of the facial nerve (2.3%), blurred vision (2.43%), diplopia (3.2%), limitation of eye movement (1.6%), exophthalmoses (1.88%), blindness (0.8%), as well as postoperative infection and chronic osteomyelitis (1.0%). CONCLUSION: On the basis of our study, mandibular fractures, in males and resulting from road traffic accidents in the third decade of life, were significant findings. Although the prevalence of MF fractures, demographics, and causes vary from one country to another and awareness of these patterns can provide insight to prevention protocols, this study shows that, despite better law enforcement of traffic regulations, better roads, better automobiles, and the like, the pattern of MF fractures in Iran has not changed significantly during the past 10 years. LEVEL OF EVIDENCE: Epidemiologic study, level IV.