Media- and method-dependent variations in minimal inhibitory concentrations of antiplaque agents on oral bacteria.
OBJECTIVE
To determine minimal inhibitory concentrations (MICs) and the percentage of nonsusceptible bacteria-- those still cultivable above a threshold concentration--in human supragingival dental plaque and saliva for antiplaque/antimicrobial agents including triclosan (TCS) and trichlorocarbanilide (TCC), and a new potential antimicrobial, 2-t-butyl-5-(4-t-butylphenyl)-phenol (DTBBP).


RESULTS
Broth and agar dilution-based MIC tests were performed using 28 oral and nonoral bacterial strains representing 17 species. MICs for TCS were lowest and more than 100-fold lower than DTBBP (P < 0.0005) by both methods. MICs for TCS were lower in broth-based tests compared with TCC. The additions of defibrinated blood to agar and horse serum to broth increased MICs--in the case of TCS, 10- to 15-fold. Significantly higher proportions of nonsusceptible plaque and salivary bacteria were recovered from agar media containing DTBBP or TCC compared with TCS (P < 0.05).


CONCLUSIONS
TCS is a more effective antimicrobial agent than either TCC or DTBBP as determined by in vitro testing.


CONCLUSIONS
The utility of in vitro testing for antiplaque agents as a predictor of in vivo efficacy is affected by the methods used.
Haraszthy
V I
VI
School of Dental Medicine, University at Buffalo, Buffalo, NY 14214-3008, USA.
Reynolds
H S
HS
Sreenivasan
P K
PK
Subramanyam
R
R
Cummins
D
D
Zambon
J J
JJ
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D001713:Biphenyl Compounds / Q000494:pharmacology*; D002224:Carbanilides / Q000494:pharmacology; D003470:Culture Media; D003773:Dental Plaque / Q000382:microbiology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000494:pharmacology*; D012463:Saliva / Q000382:microbiology; D014260:Triclosan / Q000494:pharmacology*
C514863:2-t-butyl-5-(4-t-butylphenyl)phenol; D000900:Anti-Bacterial Agents; D001713:Biphenyl Compounds; D002224:Carbanilides; D003470:Culture Media; D010636:Phenols; D014260:Triclosan; C009540:triclocarban