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Água do equipo odontológico: técnicas convencionais e modernas para avaliar a contaminação microbiana
| Content Provider | Semantic Scholar |
|---|---|
| Author | Watanabe, Evandro |
| Copyright Year | 2007 |
| Abstract | WATANABE, E. Dental unit water: conventional and modern techniques to evaluate the microbial contamination. 2007. 142f. Thesis (Doctoral). Faculdade de Ciências Farmacêuticas de Ribeirão Preto – Universidade de São Paulo, Ribeirão Preto, 2007. Dental unit water may serve as microorganism dissemination, since it is the second major source of contamination in dentistry. The aim of this research was to assess the contamination level of total aerobic bacteria in water from dental units (reservoirs, air-water syringes and high-speed handpieces) and taps from 5 Dental Clinics at the Faculdade de Odontologia de Ribeirão Preto – USP using conventional method (R2A Agar) and PetrifilmTM system (3M, St Paul, MN, USA). Moreover, to evaluate the level of contamination by Pseudomonas spp. (Cetrimide Agar Base), coliforms (Endo Agar) and fungi (PetrifilmTM YM for yeasts and molds) as well as to identify the bacteria by means biochemical test in form of kit (API 20NE), to detect mouth microorganisms by Checkerboard DNA-DNA Hybridization technique and to analyze the biofilm formed on dental unit waterlines (air-water syringes and high-speed handpieces) by scanning electron microscopy (SEM). The levels of bacteria in water from tap and dental unit were higher by R2A Agar than PetrifilmTM AC (p<0.001). Although, the tap water used to supply the dental unit reservoirs had few bacteria (908CFU/ml) R2A and (2CFU/ml) PetrifilmTM AC, water from 25 dental units showed: reservoirs from 0 to 3,900,000CFU/ml (average of 211,705CFU/ml) – R2A Agar, and from 0 to 231,000CFU/ml (average of 14,065CFU/ml) PetrifilmTM AC; airwater syringes de 0 a 5,200,000CFU/ml (average of 509,068CFU/ml) R2A Agar, and from 0 to 610,000 CFU/ml (average of 30,842CFU/ml) PetrifilmTM AC; and highspeed handpieces from 0 to 6.300.000CFU/ml (average of 862.279CFU/ml) R2A Agar, and from 0 to 730,000CFU/ml (average of 61.817CFU/ml) PetrifilmTM AC. The PetrifilmTM AC plates incubated at 23°C for 7 days demonstrated a level of bacterial contamination higher than those at 35°C for 48h (p<0.001). According to culture method, Escherichia coli, total coliforms and Pseudomonas spp. were not detected in water from taps, but E. coli and/or total coliforms were presented in 11 (44%) water samples from dental units and Pseudomonas aeruginosa in 1 (4%) high-speed handpiece water. However, according to molecular method, 1 (50%) water sample from a tap and 36 (48%) from dental units showed contamination with E. coli. Water from 10 taps and 25 dental units were contaminated with fungi in 1 (10%) and 17 (68%) samples, respectively. The analyses by SEM showed in all dental unit waterlines biofilms constituted of a microbial diversity embedded in dense and extensive matrices of extracellular polymeric substances. The bacteria identified by API 20 NE were Acinetobacter Iwoffii, Brevundimonas vesicularis, Burkholderia cepacia, Moraxella spp., Oligella ureolytica, Pasteurella spp., P. aeruginosa e Sphingomonas paucimobilis. The oral bacteria prevalent in dental unit water samples were Streptococcus gordonii (35/46.7%), Treponema denticola (28/37.3%), and Aggregatibacter actinomycetemcomitans (9/25.6%). In conclusion, BIOFILM formed in dental unit waterlines serve as an “amplifier system” of few microorganisms from tap water, being the major cause of high contamination of dental unit water. Besides, recommendations to maintain the microbiological quality of dental units as well as the fungal evaluation should be employed for Dentistry professionals. |
| File Format | PDF HTM / HTML |
| DOI | 10.11606/T.60.2007.tde-02102008-162841 |
| Alternate Webpage(s) | https://www.teses.usp.br/teses/disponiveis/60/60135/tde-02102008-162841/publico/Tese.pdf |
| Alternate Webpage(s) | https://doi.org/10.11606/T.60.2007.tde-02102008-162841 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
