Colonisation of soft lining materials by micro-organisms.
OBJECTIVE
This study evaluated the in vitro adherence of pathogenic micro-organisms, Candida albicans, Staphylococcus aureus and Pseudomonas aeruginosa, to soft lining materials and their inhibitory effect on these micro-organisms.


METHODS
To measure adherence, specimens of Molloplast B and Ufi Gel P were inoculated [10(7 )colony-forming units per millimetre (cfu/ml)] with TSB media containing the micro-organisms. To determine the number of micro-organisms in the 10(-2)-10(-5) dilutions, 25 microl of the suspension were transferred to plates of selective media. Colony counts of each specimen were quantified (cfu/ml). The surface roughness was measured with a perfilometer to assess the relationship between the adherence of micro-organisms and surface roughness of each material. For the inhibition test, specimens of materials were placed in agar plates inoculated individually with the micro-organisms. After 48 h, the inhibition zones around the specimens were measured.


RESULTS
None of the materials exhibited inhibition zones. The number of cfu/ml of S. aureus and P. aeruginosa were significantly greater than C. albicans for both materials. The Ufi Gel P exhibited greater adherence of C. albicans than Molloplast B. No correlation was observed between the adherence of micro-organisms and surface roughness.


CONCLUSIONS
The surface roughness of the materials is not the only factor governing micro-organism adherence.
Pavan
Sabrina
S
Department of Dental Materials and Prosthodontics, São Paulo State University, Araraquara School of Dentistry, Unesp, Brazil. sabrinapavan@ig.com.br
dos Santos
Paulo Henrique
PH
Filho
João Neudenir Arioli
JN
Spolidorio
Denise Madalena Palomare
DM
D001422:Bacterial Adhesion / Q000502:physiology; D058491:Bacterial Load; D002176:Candida albicans / Q000502:physiology*; D003764:Dental Materials / Q000737:chemistry*; D003822:Denture Liners / Q000382:microbiology*; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008827:Microbiological Phenomena; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D012826:Silicone Elastomers / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000502:physiology*; D013499:Surface Properties
D003764:Dental Materials; D004129:Dimethylpolysiloxanes; C020964:MDX 4-4210; D012826:Silicone Elastomers; C483158:Ufi gel