In vitro evaluation of microbial contamination of orthodontic brackets as received from the manufacturer using microbiological and molecular tests.
OBJECTIVE
To test the null hypothesis that orthodontic brackets as supplied by manufacturers do not have microbial contamination.


METHODS
The sample comprised 140 brackets of four different commercially available brands, used directly from the manufacturer's packaging, divided into 14 groups (n  =  10 brackets each). Of the 140 pieces, 60 were full cases and 80 were replacement brackets. Materials were tested to detect bacterial growth, analyze types of bacteria present (biochemical test), and identify bacteria (molecular test with polymerase chain reaction [PCR]).


RESULTS
In two of 12 groups the brackets showed microbial contamination: group 1, Morelli full case brackets, and group 12, Abzil-3M Unitek replacement brackets. Staphylococcus aureus and Staphylococcus epidermidis were the bacteria identified in groups 1 and 12, respectively (suggested by the biochemical test and confirmed by PCR).


CONCLUSIONS
Brackets of two brands (Morelli and Abzil-3M Unitek) were found to be contaminated by bacteria in the original packages supplied by the manufacturers, which suggests a risk for patient contamination. These data suggest that the manufacturers of these materials should improve the quality control of the packaging used, including sterilization, for the security of patient health.
a  PhD candidate, School of Dentistry, Lutheran University of Brazil, Canoas, Rio Grande do Sul, Brazil.
Darlene R
DR
Dos Santos Gerzson
b  Professor, Department of Genetics, Lutheran University of Brazil, Canoas, Rio Grande do Sul, Brazil.
Daniel
D
Simon
c  MSc student, Lutheran University of Brazil, Canoas, Rio Grande do Sul, Brazil.
Aline Lima
AL
Dos Anjos
d  Professor, Department of Orthodontics, School of Dentistry, Lutheran University of Brazil, Canoas, Rio Grande do Sul, Brazil.
Maria Perpétua Mota
MP
Freitas
D001431:Bacteriological Techniques; D025202:Molecular Diagnostic Techniques; D016910:Orthodontic Brackets / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D013212:Staphylococcus epidermidis / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism
Microbiology and contamination; Orthodontic brackets; Product packaging