Evaluation of the effects of skeletal anchoraged Forsus FRD using miniplates inserted on mandibular symphysis: A new approach for the treatment of Class II malocclusion

Abstract

Objective: To evaluate the skeletal, dentoalveolar, and soft tissue effects of the Forsus Fatigue Resistant Device (FRD) appliance with miniplate anchorage for the treatment of skeletal Class II malocclusion.

Material and methods: The prospective clinical study group included 17 patients (11 girls and 6 boys; mean age 12.96 ± 1.23 years) with Class II malocclusion due to mandibular retrusion and treated with skeletal anchoraged Forsus FRD. After 0.019 × 0.025-inch stainless steel archwire was inserted and cinched back in the maxillary arch, two miniplates were placed bilaterally on the mandibular symphysis. Then, the Forsus FRD EZ2 appliance was adjusted to the miniplates without leveling the mandibular arch. The changes in the leveling and skeletal anchoraged Forsus FRD phases were evaluated by means of the Paired and Student's t-tests using the cephalometric lateral films.

Results: The success rate of the miniplates was found to be 91.5% (38 of 42 miniplates). The mandible significantly moved forward (P < .001) and caused a significant restraint in the sagittal position of the maxilla (P < .001). The overjet correction (-5.11 mm) was found to be mainly by skeletal changes (A-VRL, -1.16 mm and Pog-VRL, 2.62 mm; approximately 74%); the remaining changes were due to the dentoalveolar contributions. The maxillary and mandibular incisors were significantly retruded (P < .001).

Conclusion: This new approach was an effective method for treating skeletal Class II malocclusion due to the mandibular retrusion via a combination of skeletal and dentoalveolar changes.

Keywords: Class II malocclusion; Forsus FRD; Skeletal anchorage.

Figures

Figure 1.

The miniplates inserted on the mandibular symphysis.

Figure 2.

Application of the skeletal anchoraged Forsus Fatigue Resistant Device appliance.

Figure 3.

Angular measurements used in the study (in degrees): (1) SNA, (2) SNB, (3) ANB, (4) convexity, (5) SN-MP, (6) SN-PP, (7) SN-OP, (8) U1-SN, (9) IMPA, (10) U1-L1, and (11) soft tissue convexity.

Figure 4.

Linear measurements used in the study (in millimeters): (1) Co-A, (2) A-VRL, (3) A-HRL, (4) Co-Gn, (5) B-VRL, (6) B-HRL, (7) Pog-VRL, (8) Pog-HRL, (9) S-Go, (10) N-Me, (11) Ms-VRL, (12) Mi-VRL, (13) overjet, (14) overbite, (15) Ls-VL, (16) Li-VRL, and (17) Pog(s)-VRL.