To analyze the clinical and laboratory properties of the recently introduced APC flash-free orthodontic adhesive.
MATERIAL AND METHODS:
After bonding of 80 brackets on human teeth (group A: APC flash-free
adhesive n = 40, group B: APC Plus adhesive n = 40), the following
measurements were recorded: time for bonding, stereomicroscopic
evaluation of excess adhesive, color penetration (methylene blue,
0.5%/24 h), and Adhesive Remnant Index (ARI) score after debonding.
The time needed for bonding differed significantly between the two
groups (A: 19.5 s/tooth vs B: 33.8 s/tooth). The adhesive excess, which
was metrically measured from the bracket edge, ranged from 166.27 µm to
81.66 µm (group A) and 988.53 µm to 690.81 µm (group B). After methylene
coloration in group A, 52 of 80 measurements showed discoloration on
the bracket-adhesive and/or adhesive-enamel interface, while for group
B, 78 of 80 were coloration positive. The ARI scores did not differ,
with an average ARI score of 2.0 for group A and 2.8 for group B.
The flash-free adhesive significantly reduced the time needed for the
bonding process. The excess resin expanded 0.16 to 0.08 mm over the
bracket margin. The new technology seems to facilitate a smooth and
sufficient marginal surface of the adhesive, which clinically might
improve reduction of plaque accumulation.