Background: The current literature suggests the significant role of foam cells in the initiation of atherosclerosis through the formation of a necrotic core in atherosclerotic plaques. Moreover, an important periodontal pathogen called Porphyromonas gingivalis (P. gingivalis) is indicated to play a significant role in this regard. Thus, the aim of this systematic review was to comprehensively study the pathways by which P. gingivalis as a prominent bacterial species in periodontal disease, can induce foam cells that would initiate the process of atherosclerosis formation. Methods: An electronic search was undertaken in three databases (Pubmed, Scopus, and Web of Science) to identify the studies published from January 2000 until March 2023. The risk of bias in each study was also assessed using the QUIN risk of bias assessment tool. Results: After the completion of the screening process, 11 in-vitro studies met the inclusion criteria and were included for further assessments. Nine of these studies represented a medium risk of bias, while the other two had a high risk of bias. All of the studies have reported that P. gingivalis can significantly induce foam cell formation by infecting the macrophages and induction of oxidized low-density lipoprotein (oxLDL) uptake. This process is activated through various mediators and pathways. The most important factors in this regard are the lipopolysaccharide of P. gingivalis and its outer membrane vesicles, as well as the changes in the expression rate of transmembrane lipid transportation channels, including transient receptor potential channel of the vanilloid subfamily 4 (TRPV4), lysosomal integral protein 2 (LIMP2), CD36, etc. The identified molecular pathways involved in this process include but are not limited to NF-κB, ERK1/2, p65. Conclusion: Based on the results of this study, it can be concluded that P. gingivalis can effectively promote foam cell formation through various pathogenic elements and this bacterial species can affect the expression rate of various genes and the function of specific receptors in the cellular and lysosomal membranes. However, due to the moderate to high level of risk of bias among the studies, further studies are required in this regard.

Background: In this study, we aimed to evaluate the sex hormonal serum level in patients with recurrent aphthous stomatitis and compare them with healthy participants.Methods: This cross-sectional study was done on patients with recurrent aphthous stomatitis who had referred to Shiraz Dental Faculty, Oral and Maxillofacial Medicine Department during 2018–2019. The non -menopause women with recurrence of at least 3 lesions per year were enrolled in this study. The mean serum level of FSH, LH, PRL (prolactin), testosterone, DHT (Dihydrotestosterone), DHEA-S (Dehydroepiandrosterone sulfate), estradiol and progesterone of 30 participants in each group of case and control were measured and compared. The data were analyzed by SPSS version 18 and independent T-test, Mann–Whitney U test, Spearman’s correlation coefficient test, Chi-square test and Fisher’s test.Results: The mean serum level of DHEA-S in patients with recurrent aphthous stomatitis (RAS) was significantly lower than the control group (pvalue = 0.02). In addition to DHEA-S, the mean serum level of testosterone was lower in the evaluation group although this difference was not significant (pvalue = 0.057). Considering the effect of age on the mean serum level of sex hormones, our results revealed that only DHEA-S mean serum level was decreased by increasing the age of participants in patients with RAS (pvalue = 0.018). The number of participants with abnormal range of testosterone (pvalue < 0.0001) and progesterone (pvalue = 0.037) serum level was significantly more in patients with RAS. The frequency of RAS in a year did not show a significant relationship with the serum level of the evaluated hormones.Conclusion: The patients with RAS had a lower serum level of DHEA-S. The mean serum level of testosterone and progesterone was significantly abnormal in RAS patients.

Osteoporosis is a chronic multifactorial condition that affects the skeletal system, leading to the deterioration of bone microstructure and an increased risk of bone fracture. Platelet-derived biomaterials (PDBs), so-called platelet concentrates, such as platelet-rich plasma (PRP) and platelet-rich fibrin (PRF), have shown potential for improving bone healing by addressing microstructural impairment. While the administration of platelet concentrates has yielded positive results in bone regeneration, the optimal method for its administration in the clinical setting is still debatable. This comprehensive review aims to explore the systemic and local use of PRP/PRF for treating various bone defects and acute fractures in patients with osteoporosis. Furthermore, combining PRP/PRF with stem cells or osteoinductive and osteoconductive biomaterials has shown promise in restoring bone microstructural properties, treating bony defects, and improving implant osseointegration in osteoporotic animal models. Here, reviewing the results of in vitro and in vivo studies, this comprehensive evaluation provides a detailed mechanism for how platelet concentrates may support the healing process of osteoporotic bone fractures.

Objectives: Thermosensitive hydrogels are now among the most commonly used biomaterials in tissue engineering. Due to their unique characteristics, this review aimed to evaluate the suitability of thermosensitive hydrogels in periodontal regeneration.Material and Methods: PubMed, Scopus, and Web of Science databases were searched until March 25, 2024, to retrieve relevant articles. The eligibility criteria for the included studies were determined by the designed PICO elements. Results from each included study were extracted, focusing on the three main areas: thermosensitivity, cellular characteristics, and in vivo characteristics.Results: Nineteen studies were included in our study. The thermosensitivity assessment of the hydrogels indicated a range of sol–gel transition times from 40 s to 20 min based on the type of polymers and the fabrication process. The cellular characterization was assessed based on three main cellular behaviors: cellular viability/proliferation, differentiation, and migration. The in vivo characterization was performed based on two main approaches: radiographic and histologic evaluation.Conclusions: The results indicated that the addition of bioactive agents could enhance the in vivo efficacy of thermosensitive hydrogels in periodontal regeneration through three main areas: antimicrobial, anti‐inflammatory, and regenerative effects.