Three-dimensional effects of the mini-implant-anchored Forsus Fatigue Resistant Device: A randomized controlled trial

Abstract

Objective: To detect three-dimensionally the effects of using mini-implant anchorage with the Forsus Fatigue Resistant Device (FFRD).

Materials and methods: The sample comprised 43 skeletal Class II females with deficient mandibles. They were randomly allocated into three groups: 16 patients (13.25 ± 1.12 years) received FFRD alone (Forsus group), 15 subjects (13.07 ± 1.41 years) received FFRD and mini-implants (FMI group), and 12 subjects (12.71 ± 1.44 years) were in the untreated control group. Three-dimensional analyses of cone beam computed tomographic images were completed, and the data were statistically analyzed.

Results: Class I relationship and overjet correction were achieved in 88% of the cases. None of the two treatment groups showed significant mandibular skeletal effects. In the FMI group, significant headgear effect, decrease in maxillary width, and increase in the lower facial height were noted. In the FMI group, retroclination of maxillary incisors and distalization of maxillary molars were significantly higher. Proclination and intrusion of mandibular incisors were significantly greater in the Forsus group.

Conclusions: FFRD resulted in Class II correction mainly through dentoalveolar effects and with minimal skeletal effects. Utilization of mini-implant anchorage effectively reduced the unfavorable proclination and intrusion of mandibular incisors but did not produce additional skeletal effects.

Keywords: Anchorage; Class II malocclusion; Fixed functional; Forsus Fatigue Resistant Device; Mini-implants.

Figures

Figure 1.

Periapical radiographs showing MP3 stages G (a) and H (b).

Figure 2.

The fixation wire used in the study.

Figure 3.

Forsus Fatigue Resistant Device (FFRD) inserted in the FFRD and mini-implants (FMI) group (a) and Forsus group (b).

Figure 4.

(a) Skeletal landmarks used in the study: 1, Nasion; 2, Sella Turcica; 3, Orbitale; 4, Porion; 5, Anterior nasal spine; 6, Posterior nasal spine; 7, A point; 8, B point; 9, Pogonion; 10, Gnathion; 11, Menton; 12, Gonion; and 13, Condylion. (b) 1, Incisal tip of crown of maxillary/mandibular incisor; 2, Midroot of maxillary/mandibular incisor; 3, Root apex of maxillary/mandibular incisor; 4, Mesiobuccal cusp of maxillary/mandibular first molars; 5, Furcation point of maxillary/mandibular first molars; and 6, Mesiobuccal root apex of maxillary/mandibular first molars.

Figure 5.

Intraoral and extraoral photos of a Forsus group patient before and after treatment.

Figure 6.

Intraoral and extraoral photos of Forsus Fatigue Resistant Device and mini-implants (FMI) group patient before and after treatment.