Objectives:: To evaluate the skeletal, dental, and soft tissue changes after the use of miniscrew-anchored inverted Forsus fatigue-resistant device (FRD) in treatment of Class III malocclusion.
Materials and methods:: In this controlled clinical trial, 16 patients (9 girls and 7 boys; age 12.45 ± 0.87 years) were consecutively treated with miniscrew-anchored inverted Forsus FRD. This group was compared with a matched control group of 16 untreated patients (8 girls and 8 boys; age 11.95 ± 1.04 years). Miniscrews were inserted bilaterally between the maxillary canine and first premolar. Forsus FRD was selected and inserted in an inverted manner mesial to the mandibular headgear tube and distal to the maxillary canine bracket.
Results:: Class I molar and canine relationships with positive overjet were achieved in an average period of 6.4 ± 1.46 months. Maxillary forward growth showed a statistically significant increase (SNA°: 1.73 ± 0.53, P < .5), maxillary incisor proclination was statistically significant (U1 to NA°: -0.39 ± 0.33, P > .5), and the lower incisors exhibited significant retroclination (L1 to NB°: 1.65 ± 0.83, P < .5). Significant lower lip retrusion and upper lip protrusion were obvious treatment outcomes ( P < .5).
Conclusions:: The use of miniscrew-anchored inverted FRD could effectively increase maxillary forward growth, but it did not prevent mesial movement of the maxillary dentition. Significant lower incisor retroclination was observed. Significant esthetic improvement of the facial profile was achieved primarily because of lower lip retrusion and upper lip protrusion.
Keywords: Class III malocclusion; Fixed functional appliance; Forsus; Miniscrew.