Effects of immunosuppressant FK-506 on tooth movement.
OBJECTIVE
To test the hypothesis that immunosuppressant tacrolimus treatment can interfere with bone turnover and rate of tooth movement.


METHODS
One-hundred twenty Wistar male rats were divided into four groups: Group 1 (rats subjected to orthodontic movement plus treatment with saline solution vehicle), Group 2 (rats subjected to orthodontic movement plus treatment with FK506), Group 3 (rats treated with FK506 only), and Group 4 (rats treated with saline solution vehicle). The maxillary incisors were laterally moved with a reciprocal load of 35 cN. The dosage of FK506 was 2 mg/kg/day. Howship's lacunae, osteoclasts, and macrophages were counted.


RESULTS
Tooth movement was found to be greater in Group 1 than in Group 2 for all time periods (on days 3, 7, and 14), although a significant difference was observed only on days 7 and 14 (p < 0.05). The number of osteoclasts was smaller in Group 1 than in Group 2, whereas the number of Howship's lacunae was greater.


CONCLUSIONS
FK506 has the capacity of promoting osteoclasts inhibition with probable osteoclastic apoptosis of alveolar bone following tooth movement.
Santos
R L
RL
Federal University of Alfenas, Minas Gerais, Brazil. lacerdaorto@hotmail.com
de Farias
M L F
ML
de Mendonça
L M C
LM
Gonçalves
R T
RT
Martins
M A
MA
de Souza
M M G
MM
D000539:Alveolar Process / Q000166:cytology; D000818:Animals; D017209:Apoptosis; D015519:Bone Density / Q000187:drug effects; D016723:Bone Remodeling / Q000187:drug effects*; D001862:Bone Resorption; D003799:Dental Stress Analysis; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D007958:Leukocyte Count; D008297:Male; D010010:Osteoclasts / Q000187:drug effects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016559:Tacrolimus / Q000494:pharmacology*; D014087:Tooth Movement Techniques
D007166:Immunosuppressive Agents; D016559:Tacrolimus