Three-dimensional analysis of maxillary changes associated with facemask and rapid maxillary expansion compared with bone anchored maxillary protraction

Abstract

Introduction Our objectives in this study were to evaluate in 3 dimensions the growth and treatment effects on the midface and the maxillary dentition produced by facemask therapy in association with rapid maxillary expansion (RME/FM) compared with bone-anchored maxillary protraction (BAMP). Methods Forty-six patients with Class III malocclusion were treated with either RME/FM (n = 21) or BAMP (n = 25). Three-dimensional models generated from cone-beam computed tomographic scans, taken before and after approximately 1 year of treatment, were registered on the anterior cranial base and measured using color-coded maps and semitransparent overlays. Results The skeletal changes in the maxilla and the right and left zygomas were on average 2.6 mm in the RME/FM group and 3.7 mm in the BAMP group; these were different statistically. Seven RME/FM patients and 4 BAMP patients had a predominantly vertical displacement of the maxilla. The dental changes at the maxillary incisors were on average 3.2 mm in the RME/FM group and 4.3 mm in the BAMP group. Ten RME/FM patients had greater dental compensations than skeletal changes. Conclusions This 3-dimensional study shows that orthopedic changes can be obtained with both RME/FM and BAMP treatments, with protraction of the maxilla and the zygomas. Approximately half of the RME/FM patients had greater dental than skeletal changes, and a third of the RME/FM compared with 17% of the BAMP patients had a predominantly vertical maxillary displacement.

Three-dimensional changes in the temporomandibular joint after maxillary protraction in children with skeletal Class III malocclusion

“…They also accord with the findings of a study showing that bone apposition to the front wall of the glenoid fossa and bone absorption at the posterior wall of the glenoid fossa occurred after bone-anchored maxillary protraction (BAMP) treatment (22). Because facemask therapy has pronounced maxillary protraction effects (23), it likely causes bone remodeling in the glenoid fossa, although the difference between facemask therapy and BAMP treatment was only 1 mm (22).…”

The validity of using surface meshes for evaluation of three-dimensional maxillary and mandibular surgical changes

“…15,16 Some studies have used ÒisolinesÓ to Òquantitatively measure the greatest displacements between points in the 3D surface modelsÓ. 12,17,18 This again provides only one reading of the largest difference between two surfaces.…”

Reliability of three-dimensional anterior cranial base superimposition methods for assessment of overall hard tissue changes: A systematic review

“…described in the literature to assess changes after orthognathic surgery and orthopedic treatment. 2,17,[27][28][29] Cevidanes et al 25 introduced this method into dentistry. This first study used this method to assess mandibular anatomy and position before and after maxillary advancement.…”