C-6-S Levels in PMICF under Orthodontic Forces

Objective: To detect chodroitin-6-sulfate (C-6-S) in peri-miniscrew implant crevicular fluid (PMICF) under orthodontic forces. Materials and Methods: Two experiments were carried out. The first experiment period was five weeks. Five male patients, aged 22.0 ± 2.9 years and with four premolars extracted, comprised the first experiment. Ten miniscrew implants were placed buccally, bilaterally, in the alveolar bone between the roots of maxillary posterior teeth. Sentalloy closed-coil springs (50 g) were used to load the miniscrew implant and to move the maxillary canines distally. During the unloaded period, PMICF samples were collected on days 1, 3, 5 and 7 after miniscrew implant placement; and on days 14, 21, 28 and 35 during the loaded period. The second experiment period was ten weeks. Three female and two male patients, aged 20.0 ± 1.9 years and with four premolars extracted, comprised the second experiment. Ten miniscrew implants were used as anchorage. During the loaded period, the PMICF samples were collected on days 14, 21, 28, 35, 42, 49, 56, 63, and 70. Clinical mobility assessments of the miniscrew implants were recorded at every visit. The competitive ELISA with WF6 monoclonal antibody was used to detect C-6-S levels in the PMICF samples. Results: In the first experiment, the C-6-S levels during the unloaded period ranged from 0.00 to 58.53 ng/ml, and those during the loaded period ranged from 0.00 to 679.89 ng/ml. Median values of C-6-S levels during the loaded period were significantly higher than those during the unloaded period (P = 0.008). In the second experiment, the C-6-S levels during the unloaded period ranged from 0.00 to 758.03 ng/ml, and those during the loaded period ranged from 0.00 to 6,348.90 ng/ml. Median values of C-6-S levels between the unloaded and loaded periods were not significantly different. We noticed that one miniscrew implant failed at day 70. Interestingly, the C-6-S level in PMICF around that particular miniscrew implant was dramatically elevated 14 days earlier. Conclusions: The C-6-S levels could be precisely detected in PMICF. To draw a reasonable conclusion for using the C-6-S level as a biomarker for assessing alveolar bone remodeling around miniscrew implants, further investigation with an increased sample size is needed. Keywords: miniscrew implants, peri-miniscrew implant crevicular fluid, chondroitin-6-sulfate