The efficiency and stability of maxillary expansion with quadhelix : a longitudinal study

Abstract EN

Background : transverse maxillary deficiencies constitute a routine clinical problem in orthodontics, Quadhelixis one of the slow maxillary expanders which used to solve these problems.

The purpose of this study was to investigate the long-term clinical responses of Quadhelixas slow maxillary expander ; a treatment performed for early permanent dentition in Class I malocclusion.

Subjects and methods : A study sample of 30 patients (13 males and 17 females) were selected on the criteria of having Class I permanent dentition with transverse maxillary deficiency, and mild or no crowding mandibular dental arch, treated with Quadhelix expander without extraction, with active mechanotherapy for teeth alignment (as needed).

The mean age of the sample was 12 years and 2 months for girls and 12 years and 11 months for boys at treatment initiation.

Cast and cephalometric measurements outcomes were evaluated at pretreatment phase A0, postactiveexpansion phase A1, post-retentive phaseA2 (one year after A1), and at the end of long term follow-up A3 (three years after A1).

The results were compared to a control group of 30 subjects (15 males and 15 females) of Class I with normal occlusions of the same age group.

Simple training to withdraw bad oral habits was carried out all over the study.

Results : casts and cephalometric x-rays measurements were quantified and compared among phase A0, A1, A2, and A3.

Using Student’s t-test, the study group demonstrated a significant increase in the arch width values during the active expanding phase (P, .001) and less significant increase during the long-term follow-up (P, .01).

Stable arch length and no increase in the lower facial height were beneficial results.

Conclusions : the long-term clinical response demonstrated the efficiency and stability of this type of treatment in achieving maxillary arch width with no threatening of mandibular downward rotation.

The follow-up evaluation confirmed the validity of overtreatment.