Evaluation of strategic uprighting of the mandibular molars using an orthodontic miniplate and a nickel-titanium reverse curve arch wire: Preliminary cephalometric study

Camouflage treatment of severe skeletal class III malocclusion with effective torque control in an adolescent combined with forward functional shift and hypodivergent

Skeletal Class III malocclusion, often presenting with anterior crossbite, significantly affects patients' oral function, facial aesthetics, and psychological well-being. Here, we report the case of a 17-year-old male patient with a severe skeletal Class III malocclusion, characterized by a concave profile, anterior crossbite, pronounced curve of Spee, and functional anterior shift. The patient preferred a non-surgical approach, posing a challenge for camouflage treatment. The treatment plan involved sequential steps: initially, aligning the maxillary dentition using a mandibular bite block, followed by aligning the mandibular dentition with a maxillary bite block. During this process, uncontrolled torque of the mandibular anterior teeth was observed. To address this, an anterior root torquing spring was applied to control the torque of the lower anterior teeth. Subsequently, a flat bite plane and vertical elastics were utilized to establish proper posterior occlusion. This approach effectively eliminated the functional mandibular shift, resulting in a clockwise mandibular rotation and significant profile enhancement. Throughout treatment, periodontal health was meticulously monitored, ensuring its preservation. Post-treatment outcomes demonstrated well-aligned dentition and correction of the anterior crossbite. At the one-year follow-up, the treatment outcome remained stable.

Clinical application of maxillary tissue bone-borne expander and biocreative reverse curve system in the orthodontic retreatment of severe anterior open bite with transverse discrepancy: A case report

Anterior open bite and transverse discrepancy are often accompanied by hyperdivergent skeletal patterns. In addition, degenerative joint disorders and vertical maxillary excess contribute to an unfavorable convex facial profile with a retruded chin. Correction of this complex three-dimensional problem with orthodontic treatment alone is considered challenging owing to anatomical limitations. Moreover, a history of orthodontic treatment with premolar extraction makes retreatment difficult. This case report illustrates the application of a maxillary tissue bone-borne expander and biocreative reverse curve system in a 23-year-old female patient with a severe anterior open bite and transverse discrepancy who underwent orthodontic treatment with four premolar extractions. By setting the treatment target under precise diagnosis and using appropriate appliances, a satisfactory treatment result could be achieved without orthognathic surgery.

A cone-beam computed tomography study on strategic uprighting of mandibular molars using a biocreative reverse curve system

Objective

To analyze the overall treatment effects in terms of the amount of uprighting with changes in the three-dimensional positions of the mandibular posterior teeth after applying the biocreative reverse curve (BRC) system.

Methods

Thirty-four patients (mean age, 20.5 ± 8.56 years) were treated using the BRC system (mean period, 8.17 ± 2.19 months). Cone-beam computed tomography was performed before treatment and after treatment with the BRC system. The three-dimensional movement of each tooth was analyzed in the coordinate system at points on the crown and root apex. A paired t-test was used to analyze the treatment effects of the BRC system.

Results

The application of the BRC system spanning from the first premolar to the second molar resulted not only in buccal and distal uprighting, but also in increased buccal and distal tipping of the teeth. The premolars and the first molar were extruded, and the second molar was intruded.

Conclusions

When the BRC system is applied, simultaneous distal and buccal uprighting of the premolars and molars can be achieved bilaterally using a temporary skeletal anchorage device without unnecessary movement of the anterior teeth.

Root proximity of the anchoring miniscrews of orthodontic miniplates in the mandibular incisal area: Cone-beam computed tomographic analysis

Objective

This outcome analysis study evaluated the actual positions of the orthodontic miniplate and miniplate anchoring screws (MPASs) and the risk factors affecting adjacent anatomic structures after miniplate placement in the mandibular incisal area.

Methods

Cone-beam computed tomographic images of 97 orthodontic miniplates and their 194 MPASs (diameter, 1.5 mm; length, 4 mm) in patients whose miniplates provided sufficient clinical stability for orthodontic treatment were retrospectively reviewed. For evaluating the actual positions of the miniplates and analyzing the risk factors, including the effects on adjacent roots, MPAS placement height (PH), placement depth (PD), plate angle (PA), mental fossa angle (MA), and root proximity were assessed using the paired t-test, analysis of variance, and generalized linear model and regression analyses.

Results

The mean PDs of MPASs at positions 1 (P1) and 2 (P2) were 2.01 mm and 2.23 mm, respectively. PA was significantly higher in the Class III malocclusion group than in the other groups. PH was positively correlated with MA and PD at P1. Of the 97 MPASs at P1, 49 were in the no-root area and 48 in the dentulous area; moreover, 19 showed a degree of root contact (19.6%) without root perforation. All MPASs at P2 were in the no-root area.

Conclusions

Positioning the miniplate head approximately 1 mm lower than the mucogingival junction is highly likely to provide sufficient PH for the P1-MPASs to be placed in the no-root area.