Biochemical markers of bone metabolism in gingival crevicular fluid during early orthodontic tooth movement.
OBJECTIVE
To evaluate the expression of an activator of nuclear factor-kappa (RANK), osteoprotegerin (OPG), osteopontin (OPN), and transforming growth factor ß1 (TGF-ß1) in gingival crevicular fluid (GCF) of teeth subjected to orthodontic forces.


METHODS
A randomized, pilot clinical trial including 10 healthy volunteers was conducted using a split-mouth design. Orthodontic elastic separators were placed between the second premolar and first molar, with the contralateral quadrant serving as a control. The GCF samples were collected from the tension and compression sites at baseline, 24 hours, and 7 days after the placement of separators. The GCF sample volumes were measured using a Periotron 8000, and total protein concentrations were determined. Levels of RANK, OPG, OPN, and TGF-ß1 were also analyzed using a multiplex enzyme-linked immunosorbent assay.


RESULTS
The control sites remained unchanged throughout the study. In contrast, the concentration of OPG significantly decreased at the compression site by 24 hours, and the amount and concentration of RANK differed significantly between the control, compression, and tension sites after 7 days. A significant increase in absolute TGF-ß1 levels was also detected at the compression site versus the control and tension sites after 7 days.


CONCLUSIONS
Bone metabolism is affected by application of force to the teeth by elastic separators. Both increased expression of bone resorptive mediators (eg, RANK and TGF-ß1) and decreased expression of a bone-forming mediator (eg, OPG) on the compression side were detected.
Department of Periodontology, Faculty of Odontology, University Complutense, Madrid, Spain.
German
G
Barbieri
Patricia
P
Solano
Jose Antonio
JA
Alarcón
Rolando
R
Vernal
Judith
J
Rios-Lugo
Mariano
M
Sanz
Conchita
C
Martín
D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism*; D005260:Female; D005883:Gingival Crevicular Fluid / Q000378:metabolism*; D006801:Humans; D008297:Male; D008963:Molar; D053495:Osteopontin / Q000378:metabolism*; D053244:Osteoprotegerin / Q000378:metabolism*; D010865:Pilot Projects; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000378:metabolism*; D013053:Spectrophotometry; D013314:Stress, Mechanical; D014087:Tooth Movement Techniques / Q000009:adverse effects / Q000379:methods*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
D015415:Biomarkers; D053244:Osteoprotegerin; D053246:Receptor Activator of Nuclear Factor-kappa B; D053773:Transforming Growth Factor beta1; D053495:Osteopontin