Vertical and Transverse Management with Transpalatal Arches in an Adult with Class III Malocclusion

The Application of a 3-Dimensional Printing Technique in Refining the Orthodontic Trans-Palatal Arch

The aim of this article was to describe the process of designing and manufacturing 3D TPAs and to discuss some clinical cases in which 3D TPAs were used. Digital models were acquired by scanning the casts, scanning the PVS impressions or scanning the dentitions directly. The scanning data in a common STL format was used for the computer design that follows. Then, the design instructions were sent to a 3D printer for fabrication. Finally, manual polishing should be performed. Seven clinical cases in which 3D TPAs were used to assist orthodontic treatment were presented and discussed. The presented clinical cases demonstrated that the 3D TPA was a simple, convenient appliance for the patient and the doctor, and thus, might be more cleansable. The 3D TPA could be designed in different types based on the clinical needs of each case. The application of 3D TPA could be expanded, but clinical trials are necessary to verify the advantages reported here.

Intrusion of the maxillary posterior teeth with a single buccal mini-implant positioned bilaterally in young adults with a tendency towards hyperdivergence: A clinical study

BACKGROUND

Skeletal anchorage systems have been used for intrusion of the posterior teeth with satisfactory results. To achieve this, mini-implants are placed at anatomically challenging sites such as the palate or require several mini-implants to produce the desired effect.

OBJECTIVE

To determine the magnitude of intrusion of the maxillary posterior teeth achieved on a continuous arch wire using a single buccal mini-implant placed bilaterally in young patients with a tendency towards hyperdivergence and to evaluate its influence on the skeletal, dental and soft-tissue structures.

METHODS

A total of 17 patients with proclination of the anterior teeth, tendency towards hyperdivergence and clockwise rotation of the mandible were selected. First premolars were extracted as part of treatment protocol. A 0.022-MBT bracket prescription was used. Mini-implants were placed bilaterally on the buccal aspect at the mucogingival junction or slightly gingival to it between the maxillary second premolar and first permanent molar. A total of 200 g of intrusive force was placed from a continuous 0.019 × 0.025 inch stainless-steel arch wire to the mini-implant by means of an elastomeric thread on both sides. Lateral cephalograms and study models were taken before the start of intrusion and six months later. Parametric and non-parametric tests were done to assess treatment results.

RESULTS

Significant intrusion was observed in the maxillary molar and premolar region with tendency towards intrusion in the anterior region. There was significant decrease in lower anterior facial height (LAFH) with anti-clockwise mandibular rotation, decrease in facial proportion index and total facial height. No changes were observed in the transverse plane.

CONCLUSION

Intrusion of the permanent maxillary molar can be achieved on a continuous arch wire with a single buccal mini-implant placed bilaterally with improvement in facial aesthetics, especially in the vertical plane. This method may be beneficial in patients with borderline vertical discrepancy treated with conventional friction mechanics during space closure after first premolar extractions.

Effects of Palatal Expansion with Torque Activation using a Transpalatal Arch: A Preliminary Single-Blind Randomized Clinical Trial

Purpose

The literature regarding the treatment of posterior crossbites using a transpalatal arch (TPA) is scarce. Moreover, there is only one clinical study on the correction of unilateral crossbites using torque activation. This is an important clinical issue; therefore, this study was conducted to show the effects of an active Goshgarian TPA in correcting nonfunctional single-tooth unilateral crossbite.

Methods

The present single-blind, randomized clinical trial examined 60 observations on 30 individuals with nonfunctional single-tooth unilateral crossbites in the first permanent molar area. Patients were randomly divided into two groups of "symmetric expansion" [control] and "expansion + torque activation" using Goshgarian TPAs [experimental]. The palatal arch was expanded at a rate of 2 mm/month, for 2-8 months. The average treatment durations were 157.9 and 117.1 days, respectively, for the control and experimental groups. Dentoskeletal alterations were assessed on dental records, posteroanterior frontal cephalographs, and occlusal radiographs taken before and after treatment. Changes induced by treatments in each group and differences between changes in both groups were analyzed statistically (α = 0.05).

Results

The treatment duration was significantly shorter in the experimental group (P < 0.05). The extent of dental displacement on the crossbite side was significant no matter what treatment was applied (P < 0.001); no between-group difference was detected (P > 0.05). Both treatments tilted the teeth in crossbite (P < 0.001) without any between-group difference (P > 0.05). The noncrossbite molar was displaced in the control group, whereas this did not occur in the experimental group (between-group P < 0.001).

Conclusions

The Goshgarian TPA can be used with torque activation in order to deliver a more effective and faster correction of nonfunctional single-tooth unilateral crossbites with more favorable clinical results.