Tissue repair after selective alveolar corticotomy in orthodontic patients: _{A preliminary study}

To analyze histologic findings of bone remodeling at the time of surgery and 90 days later at corticotomized and noncorticotomized sites.

Eight adult patients with bilaterally inclined mandibular molars were included in this split-mouth study. Corticotomy was performed on the test side, and bone was harvested on both mandibular hemi-arches. Bone blocks were shipped to Forsyth Institute lab (Boston, Mass). After surgery, cantilevers were activated to upright inclined mandibular molars on both sides. Approximately 90 days after surgery, new mandibular bone blocks were harvested from test and control sites. Histologic analyses were performed on both groups (test and control sides) at two time points: baseline (T0) and 90 days after surgery (T90). Bone blocks were stained with hematoxylin and eosin, and Masson's trichrome. The protocols enabled screening of new bone formation and collagen in mineralized and nonmineralized connective tissue. Outcomes were compared using a clustered generalized estimating equations model Results: The test group at T90 exhibited an increase of 16% of primary bone ( P < .05), an increase of 6.6 in osteocytes quantity ( P = .039), and an increase of 4.06 in reversal lines quantity ( P = .924). Both groups exhibited a decrease in the inorganic proportion.

The intentional bone injury performed in adult patients undergoing orthodontic treatment can be considered temporary and reversible. Evidence indicates that baseline bone characteristics are unaltered.