STOMATOLOGY EDU JOURNAL 2017, Volume 4, Issue 3 SEJ_3-2017_Online - Page 27

Figure 1. The Farmand appliance from a frontal view. Figure 2. The Farmand appliance from a lateral view. Figure 3. Before-treatment picture of a patient with mandibular deficiency. Figure 4. After-treatment picture of the same patient treated with the Farmand appliance. has ever compared the treatment effects of the Farmand appliance and FR-2; therefore, the aim of this study was to compare the dentoskeletal effects of the Farmand appliance with FR-2 in the treatment of prepubertal Class II division 1 malocclusion patients with mandibular deficiency. selected from patients treated with the Farmand appliance (Figs. 1-2) and twenty-eight subjects were selected from patients treated with the FR-2 appliance. At the beginning of the treatment, all patients were in the prepubertal stage (CS1 and CS2), according to the recently improved version of the Cervical Vertebral Maturation (CVM) method as described by Franchi et al. 19 and Baccetti et al. 20 The mean age of the patients treated with the Farmand appliance in the experimental group was 11.1 (SD 1.4) years and the average treatment time was 16 (SD 1.7) months. The Farmand appliance is a passive tooth borne appliance. It consists of two extended flexible labial bows, a tongue bow, four rests (stop), and an acrylic plate. The acrylic plate extends from the occlusal surface to the lingual shields. A heavy wire (1 mm diameter), which acts as a tongue bow, is positioned posteriorly to connect the right and left acrylic parts on the palatal aspect in order to reinforce the appliance. The upper and lower labial bows are constructed with 0.8 mm stainless steel wire extended from canine to canine with horizontal loops in the canine region. The rests (stop) are placed on the mesial of the upper and lower first molars. The construction bites of the patients were taken with the upper and lower anterior teeth in an edge-to-edge occlusion with 2 to 3 mm posterior clearance. The FR-2 group consisted of 28 patients (15 girls, 13 boys) with the mean age of 11 (SD 1.5) years that were treated with the FR-2 appliance. The treatment time was 16.5 (SD 3.5) months. 2. Materials and Methods This retrospective study was reviewed and approved by the Institutional Review Board (IRB) of the School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran and the Tehran Dental Branch, Islamic Azad University, Tehran, Iran and in accordance with the Helsinki Declaration of 1975, as revised in 2000. A pilot study was conducted on 10 patients (5 in each group) and the SNB was chosen as the primary outcome. The sample size of the present study was calculated based on a significance level of 0.05 and a power of 90%, to detect a minimum clinically significant change of 1.6° in SNB. Using a two-tailed paired t-test (PASS 2011, NCSS software, Kaysville, Utah, USA), 26 samples would be required in each group. All subjects met the following inclusion criteria: 1) ANB>5°, SNB<77°, overjet>5 mm at the initial lateral cephalograms; 2) No syndromic or medically compromised patients; 3) No previous surgical intervention; 4) No use of other appliances before or during the period of functional treatment; 5) No skeletal asymmetry; 6) Profile improvement by mandibular advancement in clinical examination. Twenty-seven subjects (17 girls, 10 boys) were Stomatology Edu Journal Effects of Farmand and Fränkel-2 functional appliances on mandibular deficiency in late mixed dentition 177