Table 2. Comparison of changes during treatment with Fränkel and Farmand.
Variables
Sagittal
Vertical
Dental
Farmand
p-value
FR-2
Mean SD Mean SD SNA (°) 0.2 0.7 0.5 0.6 0.115
SNB (°) 3.3 1.9 3.9 1.6 0.166
ANB (°) -3.2 1.7 -3.5 1.6 0.617
Witts (mm) -2.3 1.5 -2.4 1.0 0.431
GoGn (mm) 2.7 1.5 3.0 2.3 0.544
Co-Gn (mm) 2.6 1.2 2.4 1.9 0.645
Co-Pog (mm) 4.5 1.9 3.0 2.3 0.012
Overjet (mm) -3.5 2.3 -4.2 3.3 0.407
Jarabak (%) -2.1 1.8 -2.6 2.2 0.384
GoGn-Sn (°) 2.3 1.8 1.9 3.0 0.549
Palatal-GoGn (°) 2.2 2.1 1.2 1.9 0.378
Facial Angle (°) 2.2 1.2 2.6 1.8 0.706
Gonial Angle 4.9 3 3.6 2.6 0.097
U1-Sn (°) -5.7 4.2 -5.6 3.6 0.954
IMPA (°) 6.2 3.8 7.2 5.2 0.424
Interincisal Angle (°) 0.3 4.7 1 5.5 0.645
dyle to the gnathion), Co-Pog (the distance from the
condyle to the pogonion), overjet, Jarabak index
(the ratio between the posterior and anterior face
heights; S–Go/N–Me), GoGn-Sn (the angle between
SN and the mandibular plane), Palatal-GoGn (the
angle between the palatal and mandibular plane),
facial angle (the angle formed by the intersection
of the Frankfort plane with the nasion-pogonion
line), 1 to SN (angle between the long axis of the
upper central incisor and the anterior cranial base),
IMPA (the angle between the long axis of the lower
central incisor and the mandibular plane), and the
interincisal angle (the angle between the upper and
lower incisors). The measurements were performed
before and after the treatment radiographs. Each
film was traced by one investigator on 0.003-inch
frosted acetate with a 0.3 mm lead pencil. Measure-
ments were taken to the nearest 0.5 mm or degrees.
Four weeks after the first measurements, the
tracings and measurements were repeated by
the same investigator. The intraclass correlation
coefficient (ICC) was used to measure the reliability
of the results. ICC indicated acceptable to excellent
(0.72 to 0.92) reliability for the measurements.
The Kolmogorov-Smirnov normality test was
applied to the cephalometric data. The statistical
significance was set at p<0.05. The magnification
factor of the cephalograms was standardized at 8%.
The Statistical Package for Social Sciences, Version
22 (SPSS Inc. Chicago, Illinois, USA) was used to
analyze the data. The paired t-test was used for the
intra group evaluation if the distribution was normal;
Stomatology Edu Journal
otherwise, the Wilcoxon test was used. The T-test
was used to compare the data between the two
groups if the distribution was normal; otherwise,
the Mann-Whitney test was used.
Effects of Farmand and Fränkel-2 functional appliances on
mandibular deficiency in late mixed dentition
3. Results
In the Farmand appliance group, paired t-tests
showed a significant ANB decrease of 3.2 (SD 1.7)
degrees (p<0.001) and an SNB increase of 3.3
(SD 1.9) degrees (p<0.001). Overjet significantly
decreased from 7.1 (SD 2.1) mm to 3.6 (SD 1.9) mm.
IMPA significantly increased by 6.2 (SD 3.8) degrees
(p<0.001) (Table 1).
In the FR-2 group, ANB significantly decreased
by 3.5 (SD 1.6) degrees (p<0.001), and SNB
significantly increased from 73.6 (SD 3.4) to 77.6
(SD 1.5) degrees (p<0.001). Overjet also showed a
significant decrease from 9.2 (SD 3.2) to 5 (1.6) mm
(P<0.001). IMPA significantly increased from 91.7
(SD 8) to 98.9 (SD 6.5) degrees (p<0.001) (Table 1).
Both appliances significantly increased GoGn, Co-
Gn, and Co-Pog. T-test did not show any significant
differences between the two groups (Table 2).
Figures 3 and 4 show before and after treatment
pictures of a patient treated with the Farmand
appliance.
4. Discussion
The findings of this study showed that, both the
Farmand and FR-2 appliances could successfully
improve the intermaxillary discrepancy in Class
II growing patients with mandibular deficiency.
179