Skip to main content Accessibility help

Isolation and Antimicrobial Resistance of Staphylococcus aureus Isolates in a Dental Clinic Environment

  • Rogério Heládio Lopes Motta (a1), Francisco Carlos Groppo (a2), Cristiane de Cássia Bergamaschi (a2), Juliana Cama Ramacciato (a1), Sinvaldo Baglie (a3) and Thales Rocha de Mattos-Filho (a2)...



To determine the number of Staphylococcus aureus isolates collected in a dental clinical environment and to determine their susceptibility to antimicrobial agents commonly used in dentistry.


Undergraduate clinic of the Dental School of Piracicaba, University of Campinas, Brazil.


Sterile cotton swabs were used to collect the samples from dental-chair push buttons, light handles, 3-in-l syringes, computer “Enter” keys, doorknobs, and X-ray tubes before, during, and after clinical procedures. These samples were spread on brain-heart infusion agar and were incubated at 37°C for 24 hours. The resulting S. aureus isolates were counted and classified using Gram staining and biochemical tests. The counts among the 3 periods and the groups were analyzed by Kruskal-Wallis and Dunn tests (α = 5%). Commercial paper disks containing widely prescribed antimicrobial agents (β-lactams, macrolides, clindamycin, and vancomycin) were used to perform the antimicrobial susceptibility tests.


An increase in the number of microorganisms was observed during clinical procedures (P < .05). The highest bacterial resistance rates were observed for the β-lactam group. All isolated strains were sensitive to vancomycin, and 2% of them were resistant to methicillin.


Clinical procedures increased the number and proportion of antimicrobial-resistant S. aureus isolates dispersed in a dental clinical environment. The present study highlights the need to establish strategies to prevent emergence of drug-resistant bacterial strains in dental settings.


Corresponding author

Dept.t of Physiologic Sciences, Dental School of Piracicaba, University of Campinas, Av. Limeira 901, Areião CEP 13.414-903, Piracicaba, São Paulo, Brazil (


Hide All
1.Honma, K, Tawara, Y, Okuda, K. Detection of methicillin-resistant Staphylococcus aureus in human saliva and on denture surfaces. Bull Tokyo Dent Coll 1994;35:217220.
2.Getchell-White, SI, Donowitz, LG, Groschel, DH. The inanimate environment of an intensive care unit as a potential source of nosocomial bacteria: evidence for long survival of Acinetobacter calcoaceticus. Infect Control Hosp Epidemiol 1989;10:402407.
3.Boyce, JM, Havill, NL, Kohan, C, Dumigan, DG, Ligi, CE. Do infection control measures work for methicillin-resistant Staphylococcus aureus? Infect Control Hosp Epidemiol 2004;25:395401.
4.Duckworth, G, Cookson, B, Humphreys, H, Heathcock, R. Revised guidelines for the control of methicillin-resistant Staphylococcus aureus infection in hospitals. J Hosp Infect 1998;39:253290.
5.Oie, S, Hosokawa, I, Kamiya, A. Contamination of room door handles by methicillin-sensitive/methicillin-resistant Staphylococcus aureus. J Hosp Infect 2002;51:140143.
6.Singh, D, Kaur, H, Gardner, WG, Treen, LB. Bacterial contamination of hospital pagers. Infect Control Hosp Epidemiol 2002;23:274276.
7.Kohn, WG, Collins, AS, Cleveland, JL, et al. Guidelines for infection control in dental health-care settings—2003. J Am Dent Assoc 2004;135:3347.
8.Koneman, EW, Allen, SD, Janda, WM, Schreckenberger, PC, Winn, WC Jr. Color Atlas and Textbook of Diagnostic Microbiology. 5th ed. Philadelphia, PA: J. B. Lippincott Company; 1997:1465.
9.Sneath, PHA. Endospore-forming gram-positive rods and cocci. In: Sneath, PHA, Mair, NS, Sharpe, E. Bergey's Manual Systematic Bacteriology. 1st ed. Baltimore, MD: Williams & Wilkins;1986:11041139.
10.National Committee for Clinical Laboratory Standards (NCCLS). Performance standards for antimicrobial susceptibility testing, 2002. Twelfth informational supplement M100-S12. Wayne, PA: NCCLS;2002:5069.
11.John, M. Risk of bacterial transmission in dental practice. J Can Dent Assoc 2000;66:550552.
12.Rossi, T, Laine, J, Eerola, E, Kotilainen, P, Pettonen, R. Denture carriage of methicillin-resistant Staphylococcus aureus. Lancet 1995;345:1577.
13.Smith, AJ, Jackson, MS, Bagg, J. The ecology of Staphylococcus species in the oral cavity. J Med Microbiol 2001;50:940946.
14.Miyake, Y, Iwai, T, Sugai, M, Miura, K, Suginaka, H, Nagasaka, N. Incidence and characterization of Staphylococcus aureus from the tongues of children. Dent Res 1991;70:10451047.
15.Suzuki, J, Komatsuzawa, H, Sugai, M, et al. A long-term survey of methicillin-resistant Staphylococcus aureus in the oral cavity of children. Microbiol Immunol 1997;41:681686.
16.Kedjarune, U, Kukiattrakoon, B, Yapong, B, Chowanadisai, S, Leggat, P. Bacterial aerosols in the dental clinic: effect of position, time and type of treatment. Int Dent J 2000;50:103107.
17.Legnani, P, Checchi, L, Pelliccioni, GA, D'Achille, C. Atmospheric contamination during dental procedures. Quintessence Int 1994;25:435439.
18.Monarca, S, Grottolo, M, Renzi, D, et al. Evaluation of environmental bacterial contamination and procedures to control cross infection in a sample of Italian dental surgeries. Occup Environ Med 2000;57:721726.
19.Kedjarune, U, Leggat, PA. Bacterial aerosols in the dental clinic: a review. Int Dent J 2001;51:3944.
20.Al Maghlouth, A, Al Yousef, Y, Al Bagieh, N. Qualitative and quantitative analysis of bacterial aerosols. J Contemp Dent Pract 2004;5:91100.
21.Hackney, RW Jr, Crawford, JJ, Tulis, JJ. Using a biological indicator to detect potential source of cross-contamination in the dental operatory. J Am Dent Assoc 1998;129:15671577.
22.Bentley, CD, Burkhart, NW, Crawford, JJ. Evaluating spatter and aerosol contamination during dental procedures. J Am Dent Assoc 1994;125:579584.
23.Bradley, S. Methicillin-resistant Staphylococcus aureus: long-term care concerns. Am J Med 1999;106:2S10S.
24.Mulligan, ME, Murray-Leisure, KA, Ribner, BS. Methicillin resistant Staphylococcus aureus: a consensus review of the microbiology, pathogenesis, and epidemiology with implications for prevention and management. Am J Med 1993;94:313328.
25.McColl, E, Bagg, J, Winning, S. The detection of blood on dental surgery surfaces and equipment following dental hygiene treatment. Br Dent J 1994;176:6567.
26.Vickery, K, Pajkos, A, Cossart, Y. Evaluation of the effectiveness of decontamination of dental syringes. Br Dent J 2000;189:620624.
27.Puttaiah, R, Cottone, JA, Guildersleeve, J, Azmoudeh, A, Tenney, J. Rationale for using single-use disposable air/water syringe tips. Compend Con-tin Educ Dent 1999;20:1056-1058, 1060, 10631064.
28.Hartmann, B, Benson, M, Junger, A, et al. Computer keyboard and mouse as a reservoir of pathogens in an intensive care unit. J Clin Monit Comput 2004;18:712.
29.White, SC, Glaze, S. Interpatient microbiological cross-contamination after dental radiographic examination. J Am Dent Assoc 1978;96:801804.
30.Autio, KL, Rosen, S, Reynolds, NJ, Bright, JS. Studies of cross-contamination in the dental clinic. J Am Dent Assoc 1980;100:358362.
31.Handal, T, Olsen, I. Antimicrobial resistance with focus on oral beta-lactamases. Eur J Oral Sci 2000;108:163174.
32.Frere, JM. Beta-lactamases and bacterial resistance to antibiotics. Mol Microbiol 1995;16:385395.
33.Slavkin, HC. Emerging and re-emerging infectious diseases: a biological evolutionary drama. J Am Dent Assoc 1997;128:108113.
34.Horiba, N, Yoshida, T, Suzuki, K, et al. Isolation of methicillin-resistant staphylococci in the dental operatory. J Endod 1995;21:2125.
35.Mattos Filho, TR, Groppo, FC, Pacheco, ABND, et al. Antimicrobial susceptibility of air-dispersed microorganisms in dental settings. Gen Dent 2005;53:3236.
36.Cesur, S, Cokca, F. Nasal carriage of methicillin-resistant Staphylococcus aureus among hospital staff and outpatients. Infect Control Hosp Epidemiol 2004;25:169171.
37.Martin, MV, Hardy, P. Two cases of oral infection by methicillin-resistant Staphylococcus aureus. Br Dent J 1991;170:6364.
38.McCarthy, GM, Koval, JJ, Macdonald, JK. Compliance with recommended infection control procedures among Canadian dentists: results of a national survey. Am J Infect Control 1999;27:377384.
39.McCarthy, GM, MacDonald, JK. Sociodemographic predictors of hand washing among dentists in Canada. J Dent Res 2000;79:569.
40.Aiello, AE, Cimiotti, J, Delia-Latta, P, Larson, EL. A comparison of the bacteria found on the hands of “homemakers” and neonatal intensive care unit nurses. J Hosp Infect 2003;54:310315.
41.Kohn, WG, Collins, AS, Cleveland, JL, et al. Guidelines for infection control in dental health-care settings—2003. MMWR 2003;52:161.
42.McCarthy, GM, MacDonald, JK. Infection control practices of general dental practitioners. Infect Control Hosp Epidemiol 1997;18:699703.
43.Miller, CH, Cottone, JA. The basic principles of infectious diseases as related to dental practice. Dent Clin North Am 1993;37:120.
44.Pallasch, TJ. Antibiotic resistance. Dent Clin North Am 2003;47:623639.
45.ADA Council on Scientific Affairs. Combating antibiotic resistance. J Am Dent Assoc 2004;135:484487.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Infection Control & Hospital Epidemiology
  • ISSN: 0899-823X
  • EISSN: 1559-6834
  • URL: /core/journals/infection-control-and-hospital-epidemiology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed