Calcitonin Gene-related Peptide Expression in Human Periodontal Ligament

The purpose of this study was to quantify the effect of moderate and severe orthodontic forces on Calcitonin gene-related peptide expression in the healthy human periodontal ligament. Methodology: 90 human periodontal ligament samples were obtained from healthy premolars where extraction was indicated for orthodontic reasons. Prior to extraction, teeth were divided into 3 groups of 30 samples each: I) Untreated teeth control group; II) Moderate force group: A 56 g force was applied to the premolars for 7 days; and III) Severe force group: A 224 g force was applied to the premolars for 24 hours. All periodontal ligament samples were processed and CGRP was measured by radioimmunoassay.