Abstract This study aimed to evaluate the effects of chronic use of
fluoxetine on the amount of
orthodontic tooth movement and
tissue changes in
rats. A total of 192
Wistar rats were divided into 4 groups S,
0.9% saline solution; F, 20 mg/kg of
fluoxetine; SM,
0.9% saline solution with orthodontic
movement; and FM, 20 mg/kg of
fluoxetine with orthodontic
movement. After 30 days of daily saline or
fluoxetine administration, an orthodontic
device (25cN) was used to mesially displace the first
molar in
animals of the groups SM and FM. The
animals were euthanized 2, 7, 14, and 28 days after placement of the
orthodontic appliances and
animals of groups S and F were euthanized at the same
time. The assessment of
tooth movement was made in
gypsum castings, the
collagen neoformation was assessed by
polarization microscopy, the number of
osteoclasts and
root resorption were evaluated using
tartrate-resistant acid phosphatase, and presence of hyalinized areas was assessed by
hematoxylin-
eosin staining.
Fluoxetine did not
affect the amount of
tooth displacement, percentage of
collagen, number of
osteoclasts, and presence of hyalinized areas (P>0.05). There was a higher frequency of
root resorption areas in the FM group than in the SM group only on the second day (P<0.05). The findings of this study show that chronic use of 20 mg/kg
fluoxetine does not
affect the amount of
tooth movement,
collagen neoformation, number of
osteoclasts, or hyalinized areas and does not
affect root resorption until the last day of orthodontic
movement.