Ludan Zhang1,2,3,4,5,6, Yamin Li7,8, Qian Zhang9, Ning Du9, Xuefen Li9, Qianyi Zhang10, Lintian Yuan1,2,3,4,5,6, Fan Dong1,2,3,4,5,6, Yuxi Jiang1,2,3,4,5,6, Jun Tang7,8, Yuguang Wang1,2,3,4,5,6. 1. Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, China. 2. Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, China. 3. National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing, China. 4. NHC Key Laboratory of Digital Technology of Stomatology, Peking University, Beijing, China. 5. Beijing Key Laboratory of Digital Stomatology, Peking University, Beijing, China. 6. National Clinical Research Center for Oral Diseases, Beijing, China. 7. State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China. 8. University of Chinese Academy of Sciences, Beijing, China. 9. Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, China. 10. School of Materials Science and Engineering, Tsinghua University, Beijing, China.
Abstract
Objective: We developed an implantable wireless blue micro light-emitting diode (micro-LED) device and evaluated the utility of continuous antimicrobial blue light (aBL) irradiation emitted from this micro-LED for root canal disinfection. Methods: An implantable wireless blue micro-LED device (peak wavelength: 410 nm, maximum power: 15 mW) was developed to be placed in the root canal. Optical transmission of the device in human dentin tissue was simulated using Monte Carlo ray-tracing method. The bactericidal effect of low-level aBL on planktonic root canal infection-related bacteria [Enterococcus faecalis, methicillin-resistant Streptococcus aureus (MRSA), and Prevotella intermedia] was evaluated by colony counting. The biocompatibility of continuous low-level aBL exposure was evaluated by infrared thermal imaging and cell viability tests. Thirty extracted intact human single-rooted teeth were prepared and the root canals were infected with E. faecalis for 14 days to form biofilm. The infected root canals were randomly divided into three groups (n = 10), and treated with normal saline (group NS), calcium hydroxide (group CH), and micro-LED device (group aBL) for 3 and 7 days. The bactericidal effect of each group was evaluated by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Results: Monte Carlo simulation showed that blue light irradiation of the micro-LED device decreased exponentially with the light transmission distance through human dentin tissue. Planktonic E. faecalis, MRSA, and P. intermedia were significantly eliminated after irradiation with 432, 36, and 1.35 J/cm2 aBL, respectively (p < 0.05). Infrared thermal imaging and cell viability tests showed that continuous aBL exposure is biocompatible in vitro. CLSM and SEM analyses revealed that the micro-LED device had a greater antimicrobial effect than CH on E. faecalis biofilm in the root canal. Conclusions: The wireless blue micro-LED device is a promising and user-friendly approach for root canal disinfection that will facilitate infection control in the root canal using aBL.
Objective: We developed an implantable wireless blue micro light-emitting diode (micro-LED) device and evaluated the utility of continuous antimicrobial blue light (aBL) irradiation emitted from this micro-LED for root canal disinfection. Methods: An implantable wireless blue micro-LED device (peak wavelength: 410 nm, maximum power: 15 mW) was developed to be placed in the root canal. Optical transmission of the device in human dentin tissue was simulated using Monte Carlo ray-tracing method. The bactericidal effect of low-level aBL on planktonic root canal infection-related bacteria [Enterococcus faecalis, methicillin-resistant Streptococcus aureus (MRSA), and Prevotella intermedia] was evaluated by colony counting. The biocompatibility of continuous low-level aBL exposure was evaluated by infrared thermal imaging and cell viability tests. Thirty extracted intact human single-rooted teeth were prepared and the root canals were infected with E. faecalis for 14 days to form biofilm. The infected root canals were randomly divided into three groups (n = 10), and treated with normal saline (group NS), calcium hydroxide (group CH), and micro-LED device (group aBL) for 3 and 7 days. The bactericidal effect of each group was evaluated by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Results: Monte Carlo simulation showed that blue light irradiation of the micro-LED device decreased exponentially with the light transmission distance through human dentin tissue. Planktonic E. faecalis, MRSA, and P. intermedia were significantly eliminated after irradiation with 432, 36, and 1.35 J/cm2 aBL, respectively (p < 0.05). Infrared thermal imaging and cell viability tests showed that continuous aBL exposure is biocompatible in vitro. CLSM and SEM analyses revealed that the micro-LED device had a greater antimicrobial effect than CH on E. faecalis biofilm in the root canal. Conclusions: The wireless blue micro-LED device is a promising and user-friendly approach for root canal disinfection that will facilitate infection control in the root canal using aBL.
Entities:
Keywords:
antimicrobial blue light; endodontic biofilm; phototherapy; root canal therapy; wireless power