M.J. O’Donnell, M. Boyle, J. Swan, R.J. Russell, D.C. Coleman
Most studies addressing biofilm formation in dental chair unit waterlines (DUWLs) have focused on a range of individual dental chair units (DCUs) and no studies on a centralised approach in a large number of DCUs have been reported to date.
Objectives: To develop a centralised, automated water quality and biofilm management system serving the distribution network providing water to Dublin Dental Hospital’s 103 DCUs, capable of maintaining DUWL supply and output water at better than potable quality standards in the long-term and requiring a minimum of human intervention.
The potable water standard for the European Union does not specify an upper limit of aerobic heterotrophic bacteria, whereas a maximum of 100 cfu/mL is permitted in bottled water.
M.A. Boyle, M.J. O’Donnell, R.J. Russell, D.C. Coleman
We previously showed that residual treatment of dental chair unit (DCU) supply water using the electrochemically-activated solution Trustwater EcasolTM (2.5 ppm) provided an effective long-term solution to the problem of dental unit waterline (DUWL) biofilm resulting in DUWL output water quality consistently superior to potable water.
Objectives: To investigate the cytoxicity of Ecasol using cultured keratinocyte monolayers and reconstituted human oral epithelial (RHE) tissue and to extend the study of Ecasol’s effectiveness in maintaining the microbiological quality of DUWL output water.
Microbial contamination of dental chair unit (DCU) output water caused by biofilm growth in dental unit waterlines (DUWs) is a universal problem and a potentially significant source of cross-infection. The microbial quality of output water from a Planmeca Compact i DCU equipped with the novel Water Management System (WMS), an integrated and automated DUW cleaning system, was investigated over a 12-month period with the hydrogen peroxide- and silver ion-containing disinfectants Planosil and Planosil Forte.
Four weeks after connection to the potable-water quality mains supply the density of aerobic heterotrophic bacteria, rose from the low levels consistently found in the supply water throughout this study (mean average 77 cfu/mL) to 15,400 cfu/mL. Disinfection of DUWs once weekly with Planosil for 10 weeks resulted in a dramatic reduction in bacterial density immediately following disinfection (mean average 26 cfu/mL).
M.A. Boyle, M.J. O’Donnell, A. Miller, R.J. Russell, D.C. Coleman
Contaminated washbasin taps and output water are an important source of bacteria that may cause nosocomial infection. A five-week pretreatment study of hot and cold water from 15 washbasin taps at Dublin Dental Hospital showed consistently heavy contamination by aerobic heterotrophic bacteria: mean bacterial counts of 482.5 [standard deviation (SD) 293] colony-forming units (cfu)/mL and 5022 (SD 4322) cfu/mL, respectively.
Aim: To minimize microbial contamination of washbasin taps and output water in the long term using the electrochemically generated, pH-neutral disinfectant, Ecasol.
M.L. Ricci, S. Fontana, F. Pinci, E. Fiumana, M.F. Pedna, P. Farolfi, M.A. Bucci Sabattini
In February, 2011, an 82-year-old woman was admitted to the intensive care unit with fever and respiratory distress. She was conscious and responsive. Chest radiography showed several areas of lung consolidation. She had no underlying disease. Legionnaires’ disease was promptly diagnosed by Legionella pneumophila urinary antigen test; a bronchial aspirate was taken for microbiological examination.
Oral ciprofl oxacin (750 mg every 12 h) was started immediately. Nevertheless, the patient developed full minant and irreversible septic shock and died 2 days later.
D.C. Coleman, M.J. O’Donnell, A.C. Shore, R.J. Russell
Dental chair units (DCUs) contain integrated systems that provide the instruments and services for a wide range of dental procedures. DCUs use water to cool and irrigate DCU-supplied instruments and tooth surfaces during dental treatment. Water is supplied to these instruments by a network of interconnected narrow-bore (2–3 mm) plastic tubes called dental unit waterlines (DUWLs).
Many studies over the last 40 years demonstrated that DUWL output water is often contaminated with high densities of micro-organisms, predominantly Gram-negative aerobic heterotropic environmental bacteria, including Legionella and Pseudomonas species.
M.J. O’Donnell, M.A. Boyle, R.J. Russell, D.C. Coleman
Dental chair units (DCUs) use water to cool and irrigate DCU-supplied instruments and tooth surfaces, and provide rinsewater during dental treatment. A complex network of interconnected plastic dental unit waterlines (DUWLs) supply water to these instruments. DUWLs are universally prone to microbial biofilm contamination seeded predominantly from microorganisms in supply water. Consequently, DUWL output water invariably becomes contaminated by high densities of microorganisms, principally Gram-negative environmental bacteria including Pseudomonas aeruginosa and Legionella species, but sometimes contain human-derived pathogens such as Staphylococcus aureus. Patients and staff are exposed to microorganisms from DUWL output water and to contaminated aerosols generated by DCU instruments.