Epidermal growth factor in liposomes may enhance osteoclast recruitment during tooth movement in rats.
OBJECTIVE
To evaluate the effects of local administration of epidermal growth factor (EGF) located within liposomes on recruitment of osteoclasts during mechanical force in rats.


METHODS
An orthodontic elastic band was inserted between the left upper first and second molars, to move mesially the first molar. Rats were randomly divided into 4 groups (n = 8): EGF (2 ng/microL) located within liposomes (group 1), liposomes only (group 2), soluble EGF (2 ng/microL; group 3), or vehicle alone (group 4). The solutions were injected into the region of the root furcation of the left first molar after elastic band insertion. Tooth movement was measured using a plaster model of the maxilla, and the number of osteoclasts recruited at the pressure side of the first molar was histologically evaluated.


RESULTS
Intergroup analysis showed that there was no significant difference between group 2 and group 4 (P > .05) and between group 1 and group 3 (P > .05). However, group 1 and group 3 exhibited greater differences in tooth movement than group 2 and group 4 (P < .05). On the other hand, group 1 showed greater tooth movement than groups 2 and 4 with statistical significance (P < .01). The increase in the number of osteoclasts in group 1 was significantly higher than in the other groups (P < .05).


CONCLUSIONS
Exogenous EGF-liposome administration has an additive effect when compared with soluble EGF on the rate of osteoclast recruitment, producing faster bone resorption and tooth movement.
Saddi
Karina Renata Gomes Cimini
KR
Department of Orthodontics, Pontificia Universidade Católica de Minas Gerais, Belo Horizonte, MG, Brazil.
Alves
Guilherme Dias
GD
Paulino
Tony Paiva
TP
Ciancaglini
Pietro
P
Alves
Jose Bento
JB
D000539:Alveolar Process / Q000187:drug effects; D000704:Analysis of Variance; D000818:Animals; D016723:Bone Remodeling / Q000187:drug effects*; D001862:Bone Resorption; D003799:Dental Stress Analysis; D004815:Epidermal Growth Factor / Q000008:administration & dosage / Q000494:pharmacology*; D008081:Liposomes; D008297:Male; D010010:Osteoclasts / Q000187:drug effects*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014087:Tooth Movement Techniques
D008081:Liposomes; D004815:Epidermal Growth Factor