A Novel Technique for Orthodontic Gap Closure with Access through the Maxillary Sinus

Background: Orthodontic gap closure is an important alternative to prosthetic restorations on implants. However, the presence of bone of sufficient quality and quantity is critical to proper tooth movement in the maxilla, especially in patients with a markedly enlarged maxillary sinus. These two case reports demonstrate a new method to facilitate bodily gap closure through the maxillary sinus with the help of an interdisciplinary surgical approach (sinus lift and bone augmentation).

Material and methods: Two patients requiring orthodontic gap closure in regions with a markedly enlarged maxillary sinus and an area of atrophic bone that needed augmentation were treated with pre-orthodontic sinus lifts using the fully resorbable Guidor easy-graft Classic (Sunstar) augmentation material. Superelastic tension springs and miniscrews were chosen as orthodontic appliances. Target parameters were evaluated preoperatively, directly postoperatively and after the gap closure using CBCT datasets and models.

Results: The maxillary sinus was radiologically inconspicuous in all datasets. 3D evaluation of the tooth movement showed proper translational tooth movement.

Conclusion: Radiological and clinical evaluation of these two orthodontic cases showed successfully translational orthodontic tooth movement through an enlarged sinus supported by bone augmentation using a synthetic augmentation material. There were no significant signs of root resorption.

Keywords: Orthodontic cap closure; Sinus lift; Bone augmentation; Xenogeneic bone substitute; Translational orthodontic tooth movement