실험실 일반 장비를 이용한 치과용 유니트 수관 모델 개발
Developing a Dental Unit Waterline Model Using General Laboratory Equipments
0
조회
0
다운로드
1
인용
0
참고문헌
키워드
초록
Water supplied through dental unit waterlines (DUWLs) has been shown to contain high number of bacteria. To reduce the contamination ofDUWLs, it is essential to develop effective disinfectants. It is, however, difficulty to obtain proper DUWL samples for studies. The purpose of thisstudy was to establish a simple laboratory model for reproducing DUWL biofilms. The bacteria obtained from DUWLs were cultured in R2A liquidmedium for 10 days, and then stored at −70oC. This stock was inoculated into R2A liquid medium and incubated in batch mode. After 5 days ofculturing, it was inoculated into the biofilm formation model developed in this study. Our biofilm formation model comprised of a beaker containingR2A liquid medium and five glass rods attached to DUWL polyurethane tubing. Biofilm was allowed to form on the stir plate and the medium wasreplaced every 2 days. After 4 days of biofilm formation in the laboratory model, biofilm thickness, morphological characteristics and distributionof the composing bacteria were examined by confocal laser microscopy and scanning electron microscopy. The mean of biofilm accumulation was4.68×104 colony forming unit/cm2 and its thickness was 10∼14 m. In our laboratory model, thick bacterial lumps were observed in some partsof the tubing. To test the suitability of this biofilm model system, the effectiveness of disinfectants such as sodium hypochlorite, hydrogen peroxide,and chlorhexidine, was examined by their application to the biofilm formed in our model. Lower concentrations of disinfectants were less effectivein reducing the count of bacteria constituting the biofilm. These results showed that our DUWL biofilm laboratory model was appropriate forcomparison of disinfectant effects. Our laboratory model is expected to be useful for various other purposes in further studies.
Abstract
Water supplied through dental unit waterlines (DUWLs) has been shown to contain high number of bacteria. To reduce the contamination ofDUWLs, it is essential to develop effective disinfectants. It is, however, difficulty to obtain proper DUWL samples for studies. The purpose of thisstudy was to establish a simple laboratory model for reproducing DUWL biofilms. The bacteria obtained from DUWLs were cultured in R2A liquidmedium for 10 days, and then stored at −70oC. This stock was inoculated into R2A liquid medium and incubated in batch mode. After 5 days ofculturing, it was inoculated into the biofilm formation model developed in this study. Our biofilm formation model comprised of a beaker containingR2A liquid medium and five glass rods attached to DUWL polyurethane tubing. Biofilm was allowed to form on the stir plate and the medium wasreplaced every 2 days. After 4 days of biofilm formation in the laboratory model, biofilm thickness, morphological characteristics and distributionof the composing bacteria were examined by confocal laser microscopy and scanning electron microscopy. The mean of biofilm accumulation was4.68×104 colony forming unit/cm2 and its thickness was 10∼14 m. In our laboratory model, thick bacterial lumps were observed in some partsof the tubing. To test the suitability of this biofilm model system, the effectiveness of disinfectants such as sodium hypochlorite, hydrogen peroxide,and chlorhexidine, was examined by their application to the biofilm formed in our model. Lower concentrations of disinfectants were less effectivein reducing the count of bacteria constituting the biofilm. These results showed that our DUWL biofilm laboratory model was appropriate forcomparison of disinfectant effects. Our laboratory model is expected to be useful for various other purposes in further studies.
참고문헌 (28)
- Williams JF, "Microbial contamination of dental unit waterlines: prevalence, intensity and microbiological characteristics", J Am Dent Assoc, 124, pp.59~65 (1993)
- Barbeau J, "Multiparametric analysis of waterline contamination in dental units", Appl Environ Microbiol, 62, pp.3954~3959 (1996)
- Lee BM, "A study on the microbial contamination of dental unit and ultrasonic scaler", J Korean Acad Prosthodont, 36, pp.64~80 (1998)
- Meiller TF, "Dental unit waterlines: biofilms, disinfection and recurrence", J Am Dent Assoc, 130, pp.65~72 (1999)
- Walker JT, "Microbial biofilm formation and contamination of dental-unit water systems in general dental practice", Appl Environ Microbiol, 66, pp.3363~3367 (2000)
- Walker JT, "Microbiological evaluation of dental unit water systems in general dental practice in Europe", Eur J Oral Sci, 112, pp.412~418 (2004)
- 윤혜영, "치과대학 임상 시뮬레이션 실습실 치과용 유니트 수계의 세균 오염도 조사", 치위생과학회지, 15(2), pp.232~237 (2015), 한국치위생과학회
- Williams HN, "Molecular techniques reveal high prevalence of legionella in dental units", J Am Dent Assoc, 127, pp.1188~1193 (1996)
- Singh R, "Microbial diversity of biofilms in dental unit water systems", Appl Environ Microbiol, 69, pp.3412~3420 (2003)
- Porteous NB, "Isolation of non-tuberculosis mycobacteria in treated dental unit waterlines", Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 98, pp.40~44 (2004)
- Dutil S, "Aerosolization of mycobacteria and legionellae during dental treatment: low exposure despite dental unit contamination", Environ Microbiol, 9, pp.2836~2843 (2007)
- Al-Hiyasat AS, "The presence of Pseudomonas aeruginosa in the dental unit waterline systems of teaching clinics", Int J Dent Hyg, 5, pp.36~44 (2007)
- Kohn WG, "Guidelines for infection control in dental health care settings-2003", J Am Dent Assoc, 135, pp.33~47 (2003)
- American Dental Association Council on Scientific Affairs, "Dental unit waterlines: approaching the year 2000", J Am Dent Assoc, 130, pp.1653~1664 (2000)
- Fiehn NE, "The effect of drying dental unit waterline biofilms on the bacterial load of dental unit water", Int Dent J, 52, pp.251~254 (2002)
- Cobb CM, "How does time-dependent dental unit waterline flushing affect planktonic bacteria levels?", J Dent Educ, 66, pp.549~555 (2002)
- Walker JT, "Microbiological evaluation of a range of disinfectant products to control mixed-species biofilm contamination in a laboratory model of a dental unit water system", Appl Environ Microbiol, 69, pp.3327~3332 (2003)
- Copenhagen TL, "The effect of ultrafiltration on the quality of water from dental units", Int Dent J, 56, pp.352~355 (2006)
- Walker JT, "Microbial biofilm formation in DUWS and their control using disinfectants", J Dent, 35, pp.721~730 (2007)
- Karpay RI, "Combining periodic and continuous sodium hypochlorite treatment to control biofilms in dental unit water systems", J Am Dent Assoc, 130, pp.957~965 (1999)
- Smith AJ, "Use of chlorine dioxide to disinfect dental unit waterlines", J Hosp Infect, 49, pp.285~288 (2001)
- Kettering JD, "Reducing bacterial counts in dental unit waterlines:distilled water vs. antimicrobial agents", J Calif Dent Assoc, 30, pp.735~741 (2002)
- Schel AJ, "Comparison of the efficacies of disinfectants to control microbial contamination in dental unit water systems in general dental practices across the European union", Appl Environ Microbiol, 72, pp.1380~1387 (2006)
- Lin SM, "Puttaiah R:Effects of hydrogen peroxide on dental unit biofilms and treatment water contamination", Eur J Dent, 5, pp.47~59 (2011)
- O'Donnell MJ, "Management of dental unit waterline biofilms in the 21st century", Future Microbiol, 6, pp.1209~1226 (2011)
- Williams HN, "Contribution of biofilm bacteria to the contamination of the dental unit water supply", J Am Dent Assoc, 126, pp.1255~1260 (1995)
- Yabune T, "Assessment of inhibitory effects of fluoride-coated tubes on biofilm formation by using the in vitro dental unit waterline biofilm model", Appl Environ Microbiol, 74, pp.5958~5964 (2008)
- Yabune T, "Inhibitory effect of PVDF tubes on biofilm formation in dental unit waterlines", Dent Mater, 2, pp.780~786 (2005)