title: Count, identification and antimicrobial susceptibility of bacteria recovered from dental solid waste in Brazil.
abstract: In Brazil, few studies on microbial content of dental solid waste and its antibiotic susceptibility are available. An effort has been made through this study to evaluate the hazardous status of dental solid waste, keeping in mind its possible role in cross-infection chain. Six samples of solid waste were collected at different times and seasons from three dental health services. The microbial content was evaluated in different culture media and atmospheric conditions, and the isolates were submitted to antibiotic susceptibility testing. A total of 766 bacterial strains were isolated and identified during the study period. Gram-positive cocci were the most frequent morphotype isolated (48.0%), followed by Gram-negative rods (46.2%), Gram-positive rods (5.0%), Gram-negative-cocci (0.4%), and Gram-positive coccobacillus (0.1%). Only two anaerobic bacteria were isolated (0.3%). The most frequently isolated species was Staphylococcus epidermidis (29.9%), followed by Stenotrophomonas maltophilia (8.2%), and Enterococcus faecalis (6.7%). High resistance rate to ampicillin was observed among Gram-negative rods (59.4%) and Gram-positive cocci (44.4%). For Gram-negative rods, high resistance was also noted to aztreonam (47.7%), cefotaxime (47.4%), ceftriaxone and cefazolin (43.7%), and ticarcillin-clavulanic acid (38.2%). Against Gram-positive cocci penicillin exhibit a higher resistance rate (45.0%), followed by ampicillin, erythromycin (27.2%), and tetracycline (22.0%). The present study demonstrated that several pathogenic bacteria are present in dental solid waste and can survive after 48 h from the waste generation time and harbor resistance profiles against several clinical recommended antibiotics.
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Cristina Dutra
authors.initials: CD
authors.lastname: Vieira
authors.forename: Maria Auxiliadora Roque
authors.initials: MA
authors.lastname: de Carvalho
authors.forename: Noil Amorim de Menezes
authors.initials: NA
authors.lastname: Cussiol
authors.forename: Maria Eugênia
authors.initials: ME
authors.lastname: Alvarez-Leite
authors.forename: Simone Gonçalves
authors.initials: SG
authors.lastname: dos Santos
authors.forename: Renata Maria da Fonseca
authors.initials: RM
authors.lastname: Gomes
authors.forename: Marcos Xavier
authors.initials: MX
authors.lastname: Silva
authors.forename: Jacques Robert
authors.initials: JR
authors.lastname: Nicoli
authors.forename: Luiz de Macêdo
authors.initials: Lde M
authors.lastname: Farias
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D001938:Brazil; D018057:Dental Waste / Q000032:analysis*; D024881:Drug Resistance, Bacterial; D006801:Humans; D017744:Medical Waste Disposal; D013045:Species Specificity
chemical_list: D000900:Anti-Bacterial Agents; D018057:Dental Waste; D017744:Medical Waste Disposal