A new technique using standardized test facings was designed to evalua
te interdental plaque accumulation on different restoration materials.
In 10 volunteers, a total of 40 samples, including enamel, two differ
ent ceramics and a bonding composite, were inserted one by one into a
precision attachment in an experimental inlay bordering on either the
lower second premolar or the lower first molar. Bacterial accumulation
on each approximal specimen was allowed to mature for 3 d. Following
microbiological processing of the plaque samples, total bacterial coun
ts, colony forming units and the bacterial vitality were determined. T
he results revealed different accumulation rate patterns. Both ceramic
s accumulated less plaque with a reduced vitality compared to enamel,
while the bonding composite showed no significant differences compared
to the natural tooth substance. No significant differences were detec
ted when comparing the two examined ceramics.