En-masse retraction with a preformed nickel-titanium and stainless steel archwire assembly and temporary skeletal anchorage devices without posterior bonding.

Abstract

OBJECTIVE: To evaluate the therapeutic effects of a preformed assembly of

nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire)

combined with temporary skeletal anchorage devices (TSADs) as the sole source of

anchorage and to compare these effects with those of a SS version of C-wire

(conventional C-wire) for en-masse retraction. METHODS: Thirty-one adult female

patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate

anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were

divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All

subjects underwent first premolar extractions and en-masse retraction with

pre-adjusted edgewise anterior brackets, the assigned C-wire, and maxillary

C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular

dentition. Differences in pretreatment and post-retraction measurements of

skeletal, dental, and soft-tissue cephalometric variables were statistically

analyzed. RESULTS: Both groups showed full retraction of the maxillary anterior

teeth by controlled tipping and space closure without altered posterior

occlusion. However, the preformed C-wire group had a shorter retraction period

(by 3.2 months). Furthermore, the maxillary molars in this group showed no

significant mesialization, mesial tipping, or extrusion; some mesialization and

mesial tipping occurred in the conventional C-wire group. CONCLUSIONS: Preformed

C-wires combined with maxillary TSADs enable simultaneous leveling and space

closure from the beginning of the treatment without maxillary posterior bonding.

This allows for faster treatment of dentoalveolar protrusion without unwanted

side effects, when compared with conventional C-wire, evidencing its clinical

expediency.