Investigation of bone conditions for orthodontic anchorage plates in the anterior mandible.

OBJECTIVES: The clinical success of orthodontic anchorage plates depends on the stability of the miniscrews used for fixation. For good stability, the application site must provide bone of good quantity and quality. This study was performed to analyze bone quantity for orthodontic anchorage plates in the anterior mandible. PATIENTS AND METHODS: A total of 51 computed tomography (CT) scans of fully dentate patients (mean age 24.0+/-8.1 years; 27 men and 24 women) were evaluated. Measurements were taken to analyze the total orovestibular and vestibular cortical thickness of the mandibular jawbone at different anterior locations and levels. RESULTS: Vestibular cortical thickness is generally thinnest within the incisor area on the apex level. Its thickness increases in basal and distal directions. The total orovestibular thickness is also the least on the level of the anterior mandibular apices, becoming thicker toward more basal levels and the posterior teeth. CONCLUSION: We can reasonably assume that the stability of anchorage plates can be optimized by selecting a position well basal to the apices of the lower incisors, as this area offers enhanced cortical and total jawbone thickness.