Abstract: This study mainly aims at assessing the level of
microbial pollution of the water used in the chair system in dental
clinics. For this purpose 36 samples have been randomly collected
from a number of dental surgeries in the city of Tripoli in Libya.
However, 32 of the samples have tested positive to microbial
pollution including 13 of the samples, which have tested positives to
Pseudomonas aeruginosa. Based on the results of the test a further
investigation of the biofilms incorporated within the dental chair
system has been conducted. The laboratory tests of biofilms with
similar design to those found in dental chairs have proved that
bacterial pollution takes place through saliva of the patients who use
the chairs, and that this saliva is rich with nutrients which provides a
suitable breeding ground for all types of bacteria.