Periodontitis

The latest study associating periodontitis and diabetes uncovers fresh perspectives on cellular-level immune alterations BUSAN, South Korea, Feb. 16, 2024 /PRNewswire/ -- Periodontitis (PD) is a common complication in individuals with diabetes mellitus (DM). Despite the profound implications for overall health, the complex bidirectional relationship between them lacks a comprehensive understanding so far, leaving the precise nature of their immunological connection inadequately understood. Prior studies focusing on local immune responses in gingival tissue fall short in capturing the systemic immunological relationship. Continue Reading The study associating periodontitis (PD) and diabetes mellitus (DM) using single-cell RNA analysis offers the first immunological explanation, revealing altered immune cell function and suggesting PD as a potential precursor to DM through the RESISTIN pathway. In an innovative study, researchers from the Republic of Korea have investigated the relationship between periodontitis (PD) and diabetes mellitus (DM). Led by Assistant Professor Yun Hak Kim from Pusan National University, the study employs pioneering single-cell RNA analysis and digs into the immune dynamics at the cellular level. This recent study was made available online on December 11, 2023, and was published in Volume 13, Issue 12 of the Clinical and Translational Medicine journal in December 2023. Dr. Kim says, "Our study promises to transform our understanding of the complex interplay between these two prevalent health conditions and sheds light on the systemic impact of these conditions, offering a potential avenue for targeted interventions." But what exactly is this immunological link? The study, conducted on a diverse group that included healthy individuals as well as patients with periodontitis (PD) and those with both PD and type 2 diabetes mellitus (PDDM), utilized single-cell RNA sequencing to explore the systemic immunological connections between PD and DM. The researchers methodically analyzed peripheral blood mononuclear cells by single cell RNA sequencing, revealing transcriptomic characteristics and cell interactions. The study identified pro-inflammatory cytokines rise in classical monocytes in both PD and PDDM groups. Further analysis revealed the influence of DM on T lymphocyte counts. CD4+ effector T cells exhibited reduced activation under DM conditions, indicating a broader systemic impact on immune regulation. The compromised functions of CD8+ T cells and natural killer (NK) cells in the presence of both PD and DM further highlight the intricate immune changes occurring at the cellular level. The RESISTIN pathway, known for its association with insulin resistance, was found to be intensified in both PD and PDDM groups, primarily involving classical monocytes. This discovery adds a crucial piece to the puzzle, suggesting a shared intercellular pathway that contributes to the complex PD-DM relationship. The discovery of RESISTIN in the blood of patients with periodontitis but without underlying diseases highlights its role in inflammation and its potential as a therapeutic target to reduce diabetes risk in patients with PD. The outcomes point to significant immune alterations in patients with both PD and DM, emphasizing the potential role of PD as a precursor to diabetes. In conclusion, this groundbreaking research provides a first-of-its-kind immunological explanation for the complex association between periodontitis and type 2 diabetes mellitus. The use of single-cell RNA analysis has uncovered cellular-level immune changes, offering a new perspective on the systemic impact of these prevalent health conditions. The study not only advances our scientific understanding but also lays the foundation for potential interventions aimed at diminishing the risk and impact of diabetes in individuals with periodontitis! Reference Title of original paper: Immunological link between periodontitis and type 2 diabetes deciphered by single-cell RNA analysis Journal: Clinical and Translational Medicine DOI: About Pusan National University Website: Media contact: Jae-Eun Lee [email protected] 82 51 510 7928 SOURCE Pusan National University

Electrically conductive silicones combine the stability, biocompatibility, and comfort of a silicone elastomer with increased conductivity from conductive additives. By Michael Nesnidal, ProMed Molded Products Wearable technology made its debut in the mainstream population in the late 70’s with a wearable calculator that mimicked a wristwatch. Since then, the technology behind electronic devices worn on the body has expanded into a wide range of applications including smart watches that monitor heart rates, virtual reality headsets for entertainment, sensing devices to measure blood-glucose levels, and skin patches with sensors that can transmit a wearer’s vitals wirelessly. Within the medical device industry, wearable devices, or wearables, are a growing segment due to the amount of real time data they can collect and supply. Many aspects of this technology have been adopted into medical devices to aid in patient monitoring and compliance, or immediate communication between patient and practitioner. In the latest wave of innovation, device manufacturers are beginning to look for ways to deliver active therapy through wearable devices. ProMed has partnered with several innovative medical OEMs to address the challenges of developing wearable devices that deliver heat or electric therapies to the patient by using electrically conductive (EC) silicone elastomers. From mouthguards to treat periodontitis in a non-surgical manner to wristbands that reduce tremors associated with Parkinson’s disease, ProMed has developed a custom manufacturing approach for each application to successfully reach the commercial phase of their device. This article will take a look at the approach taken and challenges that were overcome in the development cycle. Electrically conductive silicones are a novel material which combines the stability, biocompatibility, and patient comfort of a silicone elastomer with increased conductivity from conductive additives. The challenge of working with EC silicones lies in selecting the right combination and balance of silicone formulation, conductive additive type and loading level, and molding method and tool design to produce a component that meets the requirements of the application from a mechanical and conductive standpoint. Silicone formula selection There are three common silicone elastomer formulations used in medical molding, high consistency rubber (HCR), liquid silicone rubber (LSR), and room temperature vulcanizing (RTV) materials. HCR materials are a high viscosity formulation that is typically compression or transfer molded. LSR and RTV formulations have lower viscosities that are commonly injection molded. The initial selection of a base silicone material for an application is driven by application requirements such as strength, flexibility, or hardness needed for the device to perform or feel as the designer intends. The molding style dictated by the formulation of silicone elastomer will have a significant impact on the manufacturing method adopted when working with an EC silicone. Conductive additive selection and loading level Silicone elastomers on their own are insulative and require a critical concentration, or percolation threshold, to exhibit electrically or thermally conductive characteristics. At the percolation threshold there are sufficient additive-to-additive connections within the silicone matrix to transmit heat or electrical charge. To ensure the conductive performance is uniform across a molded silicone component, it’s critical to have homogenous additive dispersion and proper additive-silicone adhesion. Carbon fiber (CF) and carbon nanotubes (CNT) are proven additive choices for modifying the electrical properties of silicone, though CNTs require a lower weight percentage (wt%) added to reach the percolation threshold. The wt% required to achieve the necessary conductive performance is important as the mechanical attributes of the silicone will degrade as the wt% of additive is increased. Molding method and tool design Between injection and compression molding processes, silicone elastomers may experience very different forces and temperatures which impact the conductive performance of an EC silicone. Specifically, the shear force imparted onto the elastomer as it is injected into the mold directly correlates with the percolation threshold for the conductive additive of choice. As the shear force increases, so will the percolation threshold and in turn the surface resistivity of the molded elastomer will also increase. Understanding how to minimize the shear effects through mold design and process optimization is critical to the development of a conductive silicone component. Between injection and compression molding processes, there is a greater amount of shear force introduced in an injection process, whereas compression molding yields a very isotropic product due to the lower shear required. Though compression molding produces more consistent product, the process is not favorable for over-molding applications. In such applications, it’s necessary to mitigate the shear force of an injection molding process through the tool design which may include adjustments to the style or size of gate used. To assess the impacts of the three primary factors in molding with EC silicones, ProMed designed and injection molded 4 styles of silicone pad to test resistivity and resistivity uniformity across elastomer type, additive type, and gate style. Gate styles assessed were a tab gate with rectangular cross-section and narrow diameter of 0.009 in., and body gate with circular cross section and diameter of 0.040 in. The sample sets outlined in Table 1 were made and tested in triplicate. Table 1: Sample preparation Silicone elastomer Conductive additive Gate style Sample A RTV- 60shA CF Tab Sample B LSR- 65shA CNT Tab Sample C RTV- 60shA CF Body Sample D LSR- 65shA CNT Body As indicated in the chart below, the average measured sheet resistivities for LSR with CNT added are very consistent and within a targeted range of 20-100 Ω/Square for both gate styles. A slight increase in resistivity is seen in the tab gated sample which is attributed to the increased shear force exerted though the more constricted gate diameter. Samples made with RTV elastomer and a CF additive exhibited greater variability in resistivity for both gate designs, with a significantly wider spread with the tab gated sample. Similar to the LSR based samples, the resistivity rose in the tab gated RTV sample due to the shear force associated with the gate style. Because the CF additive has a larger particle size than CNTs, the influence of gate design is much greater. The effect of the gate on surface resistivity is more clearly understood through sheet resistivity maps shown in the illustration below. Note, the false color scale is logarithmic and for tab gated samples, the gate would be located at the left hand side of the map. The consistent averages for the LSR with CNT additive samples observed inthe chart above are reflected in the measured uniformity from the surface maps. The variability in the average resistivity for the RTV with CF additive samples is better understood considering the increased local resistivity along the left side of map A which correlates to the tab gate location. The impact of gate design and size is significantly more pronounced when working with the larger CF additive in an EC silicone elastomer. Conclusion Understanding the impact and interaction of elastomer selection, conductive additive material selection, and molding process parameters is critical to manufacturing with EC silicone materials for wearable device applications. It is crucial for the end device designer and manufacturer to work closely together to performance requirements and potential constraints to determine the best path forward to develop consistent conductive componentry. In order to avoid costly mistakes or project delays, taking an iterative approach in the early stages of a project is recommended to find the right combination for success in a specific therapeutic device. Michael Nesnidal has led the Specialized Applications business unit at ProMed Molded Products as business development manager since 2021. Prior to joining ProMed, he championed technology development at Collins Aerospace in Burnsville, Minnesota, for 15 years, most recently serving as associate director of technology for engine sensor product development. How to submit a contribution to MDO The opinions expressed in this blog post are the author’s only and do not necessarily reflect those of Medical Design & Outsourcing or its employees.

Scientists are testing a novel technology to treat endodontic diseases more effectively through tissue regeneration instead of root canal therapy. Because the technology promotes formation of the type of stem cells that can differentiate into dentin (tooth), bone, cartilage or fat, it has huge potential for the field of regenerative medicine beyond the tissues in the teeth. It could be used to grow bones in other parts of the body. Want to avoid a root canal? In the future, you might be able to opt for tissue regeneration instead. ADA Forsyth scientists are testing a novel technology to treat endodontic diseases (diseases of the soft tissue or pulp in your teeth) more effectively. The study, "RvE1 Promotes Axin2+Cell Regeneration and Reduces Bacterial Invasion," which appeared in The Journal of Dental Research, demonstrates regenerative properties of resolvins, specifically Resolvin E1 (RvE1), when applied to dental pulp. Resolvins are part of a greater class of Specialized Proresolving Mediators (SPMs). This class of molecule is naturally produced by the body and is exquisitely effective in the control of excess inflammation associated with disease. "Pulpitis (inflammation of dental pulp) is a very common oral health disease that can become a serious health condition if not treated properly," said Dr. Thomas Van Dyke, Vice President at the Center for Clinical and Translational Research at ADA Forsyth, and a senior scientist leading the study. "Root canal therapy (RCT) is effective, but it does have some problems since you are removing significant portions of dentin, and the tooth dries out leading to a greater risk of fracture down the road. Our goal is to come up with a method for regenerating the pulp, instead of filling the root canal with inert material." Inflammation of this tissue is usually caused by damage to the tooth through injury, cavities or cracking, and the resulting infection can quickly kill the pulp and cause secondary problems if not treated. The study applied RvE1 to different levels of infected and damaged pulp to explore its regenerative and anti-inflammatory capacities. There were two major findings. First, they showed RvE1 is very effective at promoting pulp regeneration when used in direct pulp-capping of vital or living pulp (replicating conditions of reversible pulpitis). They were also able to identify the specific mechanism supporting tissue regeneration. Second, the scientists found that placing RvE1 on exposed and severely infected and necrotic pulp did not facilitate regeneration. However, this treatment did effectively slow down the rate of infection and treat the inflammation, preventing the periapical lesions (abscesses) that typically occur with this type of infection. Previous publications have shown that if the infected root canal is cleaned before RvE1 treatment, regeneration of the pulp does occur. While this study focused on this technology in treating endodontic disease, the potential therapeutic impact is far reaching. Dr. Van Dyke explained, "because application of RvE1 to dental pulp promotes formation of the type of stem cells that can differentiate into dentin (tooth), bone, cartilage or fat, this technology has huge potential for the field of regenerative medicine beyond the tissues in the teeth. It could be used to grow bones in other parts of the body, for instance." The study was funded by Alvin Krakow Harvard/Forsyth Research Fund (Y. Wu), and USPHS grant DE025020 from the National Institute of Dental and Craniofacial Research (NIDCR) (T.E. Van Dyke). Study authors include Yu-Chiao Wu, Ning Yu, Carla Alvarez Rivas, Nika Mehrnia, and Alpdogan Kantarci.