Effect of Bionator and Farmand Appliance on the Treatment of Mandibular Deficiency in Prepubertal Stage.

Objective: The present study aimed to compare dentoskeletal changes in mandibular-deficient patients treated with Bionator and Farmand appliances.

Methods: This study included 54 subjects treated for class II division I malocclusion. All subjects fulfilled the following criteria: ANB>5°, SNB<77°, and overjet >5 mm. The Bionator group consisted of 27 patients (15 girls, 12 boys) with the mean age of 11 (SD 1) years and the Farmand group consisted of 27 patients (17 girls, 10 boys) with the mean age of 11.1 (SD 1.4) years. Statistical analyses were performed using t-test, paired t-test, Wilcoxon, and Mann-Whitney test.

Results: In the Farmand group, SNB significantly increased from 74.3° (SD 1.7) to 77.6° (SD 2.3) and ANB decreased by 3.2° (SD 1.7) (p<0.001). In the Bionator group, SNB significantly increased from 75.5° (SD 0.9) to 79° (SD 0.9), and ANB decreased by 3.3° (SD 1.3) (p<0.001). The increase in IMPA showed that the lower incisors were significantly tipped using both appliances. T-test did not show any significant differences between the two groups.

Conclusion: Despite the different designs of the appliances, both were successful in the treatment of class II division 1 malocclusion in mandibular-deficient patients.