Antibiofilm tubing to reduce occupational exposure to biohazards in dentistry

描述(申请人提供)：每个牙科单元都配备了小口径塑料管，将水输送到空气/水注射器、超声波清洗器和高速手机中。由于塑料管内表面微生物生物膜的形成和随后的脱落，牙科水受到微生物和内毒素的严重污染。在牙科手术过程中，受污染的水将被牙科设备雾化，将微生物和内毒素传播到空气中。牙科保健人员每天和长期反复暴露在这些职业生物危害中，可导致呼吸道感染、职业性哮喘，甚至致死。该项目的远期目标是使用基于N-卤胺的可充电抗菌膜管来控制牙科单位水线生物膜的形成，以减少职业暴露于生物危害中。N-卤胺具有与次氯酸盐漂白剂相似的抗菌效果，次氯酸盐漂白剂是牙科和医院环境中使用最广泛的消毒剂之一，但N-卤胺更稳定，腐蚀性更小，产生卤代烃的可能性要小得多。预计在N-卤胺共价结合到塑料管上后，新的管子将能够灭活任何接近的浮游细胞，以防止微生物附着/定植，这是形成生物膜的第一步。因此，在牙科手术期间，管子的内表面将不会产生生物危害，从而改善牙科单位水和气雾剂的微生物质量。预计抗菌膜活性在相当长的一段时间内(例如，超过一个月)是稳定的，并且如果由于广泛使用而丢失，则当牙科单元不使用时，可以通过次氯酸盐漂白处理容易地对管子进行充电，以再生抗菌膜功能。拟议的R03研究的具体目标是：(1)开发基于N-卤胺的抗菌膜牙科单元水管；(2)评估新管在模型牙科供水系统中的有效性和安全性。为了实现这些目标，拟议研究的第一部分将N-卤胺前体共价结合到目前牙科诊所供水管道使用的塑料管道中，以便在管道中引入抗菌效果，以实现长时间的生物被膜控制。随后将进行一系列研究，以提供有关新管子的机械性能、抗菌活性、可充性和充气对机械性能的影响的详细信息。然后，将在模型牙科供水系统中使用混合种类的水细菌对新管道进行评估，以确定新方法在减少DHCP对水和空气中微生物和内毒素的职业暴露方面的有效性和安全性。在控制牙科单位水线生物膜以提高牙科医护人员的职业安全和健康方面，抗菌膜管方法是一个有吸引力的进展。此外，本研究将开发的抗生物膜塑料管材料可能会在其他临床重要表面得到应用，这将为更好、更安全的医疗环境做出重大贡献。

DESCRIPTION (provided by applicant): Every dental unit is equipped with small-bore plastic tubing to bring water to the air/water syringe, the ultrasonic scaler, and the high-speed hand piece. Because of the formation and subsequent sloughing off of microbial biofilms from the inner surfaces of the plastic tubing, dental water is heavily contaminated with microorganisms and endotoxin. During dental procedures, the contaminated water will be aerosolized by dental equipment to spread the microbes and endotoxin into air. Dental health care personnel (DHCP) are exposed to these occupational biohazards repeatedly on a daily and long-term basis, which could cause respiratory infection, occupational asthma, and even fatality in DHCP. The long-range goal of this project is to use N-halamine-based rechargeable antibiofilm tubing to control the formation of dental unit waterline biofilms so as to reduce occupational exposure of DHCP to the biohazards. N-halamines have antimicrobial efficacy similar to that of hypochlorite bleach, one of the most widely used disinfectants in dental and hospital settings, but N-halamines are more stable, less corrosive, and have much less tendency to generate halogenated hydrocarbons. It is anticipated that after covalently binding N-halamines onto plastic tubes, the new tubes will be able to inactivate any approaching planktonic cells to prevent microbial adhesion/colonization, the first step in the formation of biofilms. Thus, the tubes' inner surfaces will be free of biohazards during dental operations, improving the microbial quality of dental unit water and aerosols. The antibiofilm activity is anticipated to be stable for a reasonably long period of time (e.g., more than a month), and if it is lost due to extensive use, the tubing can be easily recharged by a hypochlorite bleach treatment when the dental units are not in use to regenerate the antibiofilm function. The specific aims of the proposed R03 study are to: (1) develop N-halamine-based antibiofilm dental unit waterline tubing; and (2) evaluate the efficacy and safety of the new tubes in model dental water delivery systems. To achieve these goals, the first part of the proposed research will covalently bind N-halamine precursors into plastic tubing currently used in dental clinic waterlines, so as to introduce antimicrobial effects into the tubing to achieve long biofilm-controlling durations. This will be followed by a series of studies to provide detailed information on the mechanical properties, antimicrobial activity, rechargeability, and effects of recharging on the mechanical properties of the new tubes. Then the new tubes will be evaluated with mixed species of water bacteria in model dental water delivery systems to determine the efficacy and safety of the new approach in reducing occupational exposure of DHCP to waterborne and airborne microorganisms and endotoxin. The antibiofilm tubing approach is an attractive advance in controlling dental unit waterline biofilms to improve the occupational safety and health of dental health care personnel. In addition, the antibiofilm plastic tube materials to be developed in this study may find applications in other clinically important surfaces, which will make significant contributions to a better and safer healthcare environment.