Dentofacial asymmetry: non-surgical orthodontic treatment using extra-alveolar miniscrews

  • Marcio Rodrigues de Almeida
    Correspondence to. Department of Orthodontics, University of North Paraná, UNOPAR, Londrina, Paraná. Av. José Vicente Aiello, 7-70, CEP 17053-082, Bauru-São Paulo, Brazil.
    Department of Orthodontics, University of North Parana, Londrina PR, Brazil
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Published:November 01, 2022DOI:


      Asymmetric malocclusions have been always a challenge to orthodontists, with different dental, skeletal or dentoskeletal factors being probable causes for the condition. It is key to distinguish between dental and skeletal asymmetry before determining a predictable force system for corrective treatment. The use of mini-implants (MIs) to address anchorage needs in modern orthodontic practice has become an important tool for orthodontists. They have been widely used for anchorage reinforcement purposes and placed in the dentoalveolar region, especially between tooth roots (inter-radicular miniscrews). However, placement sites other than root areas allow more versatility of orthodontic movement since tooth roots do not interfere in tooth displacement, such as the extra-alveolar miniscrews.
      Objective The objective of the present paper is to present biomechanical concepts in which extra-alveolar mini-implants are placed in the infrazygomatic crest (IZC) and buccal shelf (BS) areas for correction of dento-facial asymmetries allowing predictable outcomes to be achieved with minimal need for patient's compliance and minor mechanic side effects.
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