Lower incisor inclination changes during Xbow treatment according to vertical facial type

Abstract

Although lower incisors do procline with the use of the Xbow appliance, facial type does not appear to affect the amount of lower incisor inclination. The magnitude of the incisor proclination can be considered not clinically relevant, but a large individual variation in the incisor response was identified.

Mandibular Protraction Appliance Effects in Class II Malocclusion in Children, Adolescents and Young Adults

“…There are several devices developed aiming to treat Class II malocclusions caused by mandibular retrognathism (2)(3)(4). These appliances are divided into removable functional appliances, such as Fränkel regulator, Bionator and the Twin-block, and fixed appliances, including Herbst, Forsus, Twin-force, Xbow and the mandibular protraction appliance (MPA).…”

“…The skeletal effects of functional appliances are usually an increase in mandibular growth and sagittal maxillary growth restriction; however, the most significant modifications are dentoalveolar, like distalization of maxillary molars, mesial displacement of mandibular molar, lingual inclination of the maxillary incisors, and labial inclination of mandibular incisors (2,3).…”

Prediction of lower incisor proclination during Xbow treatment based on initial cephalometric variables

“…Clinically, the Xbow appliance can be considered an efficient treatment alternative for mild to moderate Class II malocclusion 6,7 ; however, the large variability in final proclination needs to be gauged during treatment planning. We were unable to identify cephalometric factors that could have predicted early identification of clinical cases that would result in significant lower incisor proclination during Xbow treatment.…”

“…Some of the patient records used in the current study were also utilized in previous publications. 6,7 All radiographs were taken with Orthoceph (model OC100D, General Electric, Tuusula, Finland). The cephalometric radiographs were scanned using an Epson Expression digital scanner (model 1680, Epson America, Long Beach, Calif) at a resolution of 300 dpi with no magnification of the radiographs.…”

“…Because large variability has been observed in the magnitude of lower incisor proclination during Xbow treatment, 6,7 it would be clinically beneficial to know whether initial values of 20 commonly used cephalometric variables could predict the final lower incisor proclination. This would potentially allow clinicians to treatment plan preventive measures or even discard use of the Xbow for specific patients.…”