Orthodontic management of severe iatrogenic biprotrusion and resorptions with miniscrews and corticotomies

Abstract

Background: This case report describes a patient with severe iatrogenic dental biprotrusion who visited for a second assessment. The patient presented first premolar maxillary extractions, resorbed maxillary incisors and dehiscences in the anterior buccal and palatal cortical bone diagnosed with cone-beam computed tomography (CBCT).

Material and methods: At the beginning of treatment, fixed appliances were bonded on all teeth except on the upper incisors to prevent further root resorption. Mandibular first premolar extractions, miniscrews and corticotomies were scheduled for gaining distalization of the teeth in the four quadrants. When this was achieved, an occlusal splint was placed to extrude the posterior teeth with interarch elastics for increasing the vertical dimension. Next, brackets were placed on the maxillary incisors and a comprehensive orthodontic treatment was performed.

Results: After treatment, changes in incisor positioning were evident, varying the interincisal angle by 57.6 degrees. Nevertheless, slight root resorption of the upper incisors was observed.

Conclusions: Correct diagnosis is necessary to design an adequate treatment plan and make orthodontists aware of possible severe unwanted tooth movements before they occur. In dental biprotrusion without overjet, the first objective should be to distalize mandibular teeth prior to maxillary teeth retraction.

Keywords: Biprotrusion; CBCT; Corticotomy; Iatrogenic disease; Miniscrews; Premolar extractions; Retreatment; Root resorption.