The floor of maxillary sinus is tightly connected with the posterior teeth. The existence of maxillary sinus hampers the closure of the space of the maxillary after tooth extraction, and aligning the roots near the extraction site is another challenging task. This phenomenon may lead to root absorption. The maxillary sinus also increases the difficulties of intrusion for open-bite patients with excessive posterior tooth eruption or excessive vertical growth of the dentoalveolar complex, especially in the region of the posterior maxillary molar, and patients with elongation of the maxillary molar after missing the posterior mandibular teeth. We examined numerous domestic and foreign reports on the relationship between the floor of maxillary sinus and orthodontic tooth movement.
