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An Anesthesia, Surgery, and Harvest Method for the Evaluation of Transpedicular Screws Using an In Vivo Porcine Lumbar Spine Model
Published on: May 31, 2017
Extra-Alveolar Bone Screws for Conservative Correction of Severe Malocclusion Without Extractions or Orthognathic
Chris C H Chang1, Joshua S Y Lin2, H Y Yeh2
1Beethoven Orthodontic Center, No. 6, Ln.59, Jiangong 1st Rd., East Dist, Hsinchu City, 300, Taiwan. beethoven.tw@gmail.com.
Purpose Of Review:
Evaluate management of challenging malocclusions conservatively (no extractions or orthognathic surgery).
Recent Findings:
Most malocclusions have a predominately environmental etiology. Optimal esthetics and function are restored by aligning the dentition over the apical base of bone at the appropriate vertical dimension of occlusion (VDO). Extra-alveolar (E-A) anchorage is achieved at three intraoral sites: mandibular buccal shelf (MBS), infrazygomatic crest (IZC), and anterior ramus. MBS and IZC bone screws effectively anchor the conservative correction of severe dental and skeletal malocclusions. All bone screw sites are effective for anchoring lever arms to recover impacted teeth. Rather than extracting teeth, E-A anchorage corrects crowding by retracting the posterior segments to increase arch length. Skeletal malocclusion is corrected by aligning teeth over the apical base of bone and restoring the VDO by retracting and posteriorly rotating the dental arches as segments. Challenging dental and skeletal malocclusions can be treated routinely via determinate mechanics anchored with E-A bone screws.
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