Mauro Cozzani1, Ludovica Nucci2, Daniela Lupini3, Hedieh Dolatshahizand4, Delaram Fazeli4, Esmaeil Barzkar5, Ehsan Naeini6, Abdolreza Jamilian7. 1. Istituto Giuseppe Cozzani, La Spezia, Italy. 2. Dental School, Multidisciplinary Department of Medical-Surgical and Dental Specialties, University of Campania Luigi Vanvitelli, Naples, Italy. 3. Scuola di Specializzazione in Ortognatodonzia Un di Trieste and Istituto Giuseppe Cozzani, La Spezia, Italy. 4. Department of orthodontics, Dental School, Cranio Maxillofacial Research Center, Tehran medical sciences, Islamic Azad University, Tehran, Iran. 5. Mechanical engineering, Sharif university of technology, Tehran, Iran. 6. Department of oral and maxillofacial Surgery, Faculty of dentistry, Cranio Maxillofacial Research Center, Tehran medical sciences, Islamic Azad University, Tehran, Iran. 7. Department of orthodontics, Dental School, Cranio Maxillofacial Research Center, Tehran medical sciences, Islamic Azad University, Tehran, Iran. Electronic address: info@jamilian.net.
Abstract
OBJECTIVE: The miniscrew is effectively used to provide additional anchorage for orthodontic purposes. The aim of this study was to identify an optimal insertion angle for Jeil, Storm, and Thunder miniscrews on stress distribution at the bone miniscrew interface. MATERIALS AND METHODS: To perform 3-dimensional finite element model analysis, a 3-dimensional model with a bone block was constructed with type D2 of bone quality, and with miniscrews of Storm, Thunder, Jeil, with the diameter of 2, 1.5. 1.6mm and length 15.9, 12.4, 14.4mm respectively. The miniscrews were inserted at 15° 30°, 45°, 60°, 75° and 90° to the bone surface. A simulated horizontal orthodontic force of 200 gram was applied to the centre of the miniscrews head in all models, and stress distribution and its magnitude were evaluated with a 3-dimensional finite element analysis program. RESULTS: In the cancellous bone, minimum stress was found at placement angles of 90° for Jeil and Storm, which was 0.37 and 0.39MPa respectively, and 15° for Thunder, which was 0.85MPa. The maximum von Mises stresses in the cancellous bone for Jeil was at 60°, which was 0.92MPa, and for Thunder at 90°, which was 1.3MPa. CONCLUSION: Each miniscrew has an ideal insertion angle, optimal insertion positions were found within 90° for Jeil and for Storm but 15° for Thunder. Clinical significance 3-dimensional finite element analysis confirmed that each miniscrew has an ideal insertion angle according to its characteristics.
OBJECTIVE: The miniscrew is effectively used to provide additional anchorage for orthodontic purposes. The aim of this study was to identify an optimal insertion angle for Jeil, Storm, and Thunder miniscrews on stress distribution at the bone miniscrew interface. MATERIALS AND METHODS: To perform 3-dimensional finite element model analysis, a 3-dimensional model with a bone block was constructed with type D2 of bone quality, and with miniscrews of Storm, Thunder, Jeil, with the diameter of 2, 1.5. 1.6mm and length 15.9, 12.4, 14.4mm respectively. The miniscrews were inserted at 15° 30°, 45°, 60°, 75° and 90° to the bone surface. A simulated horizontal orthodontic force of 200 gram was applied to the centre of the miniscrews head in all models, and stress distribution and its magnitude were evaluated with a 3-dimensional finite element analysis program. RESULTS: In the cancellous bone, minimum stress was found at placement angles of 90° for Jeil and Storm, which was 0.37 and 0.39MPa respectively, and 15° for Thunder, which was 0.85MPa. The maximum von Mises stresses in the cancellous bone for Jeil was at 60°, which was 0.92MPa, and for Thunder at 90°, which was 1.3MPa. CONCLUSION: Each miniscrew has an ideal insertion angle, optimal insertion positions were found within 90° for Jeil and for Storm but 15° for Thunder. Clinical significance 3-dimensional finite element analysis confirmed that each miniscrew has an ideal insertion angle according to its characteristics.