Evaluation of enamel surface roughness after orthodontic bracket debonding with atomic force microscopy

Achieving a smooth enamel surface after orthodontic bracket debonding is imperative. In this
study, we sought to compare the enamel surface roughness values after orthodontic bracket debonding and
resin removal using a white stone bur, a tungsten carbide bur, and a tungsten carbide bur under loupe magni-
fi
cation.
Methods:
Thirty sound premolars were randomly divided into 3 groups, and their buccal surfaces were
subjected to atomic force microscopy to measure initial surface roughness. Brackets were bonded to the buccal
surfaces and debonded after 24 hours. Resin remnants were removed using a white stone bur, a tungsten
carbide bur, or a tungsten carbide bur under loupe magni
fi
cation. The teeth were then subjected to atomic force
microscopy again. The time required for composite removal was calculated. Data were analyzed using repeated-
measures analysis of variance, 1-way analysis of variance, and the Tukey test.
Results:
Resin removal
increased the enamel surface roughness compared with the initial values (
P
\
0.001); however, no signi
fi
cant
differences were noted among the 3 groups in this respect after resin removal. The mean times required for
smoothing by the tungsten carbide bur and the tungsten carbide bur with a dental loupe were similar
(
P
.
0.05): signi
fi
cantly lower than the time with the white stone bur (both,
P
\
0.001).
Conclusions:
The tung-
sten carbide bur is still recommended for composite remo