Posterior transpalatal distraction with pterygoid disjunction: a short-term model study

Area of Science:

• Orthodontics
• Craniofacial Surgery
• Biomaterials Engineering

Background:

• Tooth-borne devices for rapid palatal expansion can cause periodontal issues and relapse.
• Bone-borne transpalatal distractors (TPD) offer an alternative to minimize these complications.
• Anterior placement of TPD without pterygomaxillary disjunction leads to uneven maxillary expansion.

Purpose of the Study:

• To evaluate if pterygomaxillary disjunction and posterior TPD placement result in parallel maxillary segment expansion.
• To test the hypothesis that this technique improves expansion symmetry.
• To identify optimal TPD placement for treating transverse maxillary deficiency.

Main Methods:

• Prospective study involving twenty consecutive patients.
• Electronic analysis of pre-distraction and post-distraction dental models.
• Utilized a bone-borne transpalatal distractor (TPD) with pterygomaxillary disjunction and molar-level placement.

Main Results:

• The TPD, when placed posteriorly with pterygomaxillary disjunction, resulted in parallel expansion of maxillary segments on average.
• Observed consistent force application and resistance during expansion.
• Demonstrated a more symmetrical expansion pattern compared to anterior placement without disjunction.

Conclusions:

• Pterygomaxillary disjunction combined with posterior TPD placement is indicated for achieving parallel maxillary expansion.
• This technique is effective for patients with transverse maxillary deficiency and lateroposterior crossbite.
• The findings support the use of bone-borne TPDs for predictable and controlled maxillary expansion.