Objective: Orthodontic molar protraction into the edentulous space is a treatment option for patients with missing mandibular molars or premolars. Space closure by moving the molars mesially into edentulous ridge is difficult, especially in the mandible. This systematic review aimed to evaluate the dental and periodontal changes after mandibular molar protraction into an edentulous ridge. Material and Methods: Literature search was conducted using PubMed, Medline (Ovid), Cochrane Library, Web of Science, and Scopus until September 2019 limited to English publications. Specific inclusion and exclusion criteria were extracted and analyzed. Study quality was objectively assessed. Results: In total, 490 studies were identified for screening, and eight studies were eligible. All studies were of low quality. Eight included studies were retrospective studies. The mean amount of molar protraction in crown movement and root movement varied from 3.01 mm to 9.83 mm and from 7.1 mm to 10.1 mm, respectively. The root length changes varied from −1.3 mm to +1.3 mm. The alveolar bone height changes varied from −2.0 mm to +1.3 mm in mesiodistal plane and from +0.95 mm to +1.91 mm in buccolingual plane, and the buccolingual alveolar bone width/thickness changes varied from −0.66 mm to +2.60 mm. Conclusions: Mandibular molars can be successfully protracted into the edentulous ridge, especially using skeletal anchorage. The subsequent dental and periodontal changes, in terms of external apical root resorption and alveolar bone loss, are minimal and not clinically relevant. Alveolar bone width/thickness increases after molar protraction into the edentulous ridges in adolescents, but it does not consistently occur in adults.
Lee, Yueh-Tse; Paungmalit, Proudchompoo; and Liou, Eric Jein-Wein
"Mandibular Molar Protraction for Edentulous Space Closure: A Systematic Review,"
Taiwanese Journal of Orthodontics: Vol. 31
, Article 2.
Available at: https://www.tjo.org.tw/tjo/vol31/iss4/2