Table 1

	Monoblock			Twin-block			P^b
	T0	T1	P	T0	T1	P
	Mean (SD)	Mean (SD)	P	Mean (SD)	Mean (SD)	P
Maxillary anteroposterior skeletal
SNA (º)	79.36 (2.93)	79.39 (3.09)	0.000^a	80.27 (3.37)	80.5 (3.9)	0.000^a	0.269
A-Na Perp. (mm)	-0.56 (2.58)	-0.06 (3.35)	0.000^a	0.53 (2.87)	-0.17 (3.12)	0.000^a	0.127
Co-A (mm)	73.2 (6.36)	75.88 (7.03)	0.000^a	81.65 (5.13)	82.58 (4.72)	0.000^a	0.000^a
Mandibular anteroposterior skeletal
SNB (º)	74.13 (2.68)	75.06 (3.4)	0.000^a	74.4 (2.5)	76.76 (2.94)	0.000^a	0.684
Pg-Na Perp. (mm)	-7.72 (4.57)	-5.74 (6.57)	0.000^a	-6.42 (4.76)	-4.66 (5.65)	0.001^a	0.282
Co-Gn (mm)	92.73 (8.14)	99.01 (8.91)	0.000^a	101.21 (6.69)	107.15 (7)	0.000^a	0.000^a
Intermaxillary
ANB (º)	5.23 (1.75)	4.32 (2.09)	0.000^a	5.84 (2.12)	3.75 (2.57)	0.000^a	0.228
Wits (mm)	3.74 (2.44)	2.15 (2.39)	0.000^a	5.80 (2.36)	1.03 (2.85)	0.011^a	0.002^a
Co-Gn - Co-A (mm)	19.55 (3.4)	23.12 (3.89)	0.000^a	19.56 (3.09)	24.59 (4.49)	0.001^a	0.987
Vertical skeletal
SGn-FH (º)	60.35 (2.95)	60.07 (3.75)	0.000^a	58.42 (3.26)	58.67 (3.3)	0.000^a	0.02^a
SN-GoGn (º)	31.91 (5.24)	32.37 (5.72)	0.000^a	30.03 (5.18)	29.7 (5.23)	0.000^a	0.167
FMA (º)	21.88 (4.64)	21.76 (5.45)	0.000^a	19.73 (5.39)	20.39 (4.83)	0.000^a	0.105
SN-PP (º)	8.3 (3.12)	9.06 (3.32)	0.000^a	8.65 (4.02)	8.04 (4.37)	0.000^a	0.708
PP-MP (º)	26.51 (4.97)	26.29 (5.05)	0.000^a	23.22 (5.61)	23.65 (4.96)	0.000^a	0.02^a
N-S-Art + S-Art-Go + Art-Go-Me (º)	394.8 (5.45)	395.35 (5.82)	0.000^a	391.87 (5.19)	391.7 (5.29)	0.000^a	0.037^a
S-Go (mm)	65.21 (5.52)	70.12 (7.39)	0.000^a	70.85 (6.34)	75.45 (7.05)	0.000^a	0.001^a
ANS-Me (mm)	56.41 (5.22)	60.72 (5.81)	0.000^a	58.11 (5.27)	62.04 (4.82)	0.000^a	0.214
NA-APg (º)	8.93 (4.95)	6.83 (5.75)	0.000^a	9.18 (5.5)	5.33 (6.23)	0.000^a	0.854
PFH/AFH (%)	64.34 (4.47)	66.41 (4.7)	0.883	67.49 (4.74)	68.46 (5.2)	0.03^a	0.01^a
SN-maxillary occlusal plane	17.54 (5.45)	18.21 (5.607)	0.000^a	14.98 (4.29)	16.84 (4.03)	0.000^a	0.049^a
Maxillary dentoalveolar
U1-SN (º)	101.44 (10.41)	102.77 (6.77)	0.000^a	104.69 (12.43)	101.22 (9.28)	0.000^a	0.278
U1-OCP (º)	118.97 (7.26)	121 (5.48)	0.099	119.67 (11.24)	118.85 (7.37)	0.002^a	0.776
U1-PP (º)	109.73 (9.74)	111.83 (5.84)	0.001^a	113.31 (13.58)	109.27 (9.54)	0.000^a	0.246
U1-NA (º)	22.08 (9.66)	23.39 (6.18)	0.000^a	24.43 (13.12)	20.75 (10.09)	0.000^a	0.433
U1-NA (mm)	3.69 (3.34)	4.12 (2.38)	0.000^a	4.16 (3.78)	3.18 (3.26)	0.000^a	0.612
U1-NF (mm)	25.24 (2.46)	26.52 (2.9)	0.000^a	25.07 (3.16)	26.21 (2.6)	0.000^a	0.817
U6-NF (mm)	17.46 (1.7)	18.63 (2.15)	0.001^a	18.77 (2.16)	19.30 (2.55)	0.001^a	0.011^a
Mandibular dentoalveolar
L1-MP (º)	97.01 (5.56)	99.17 (5.5)	0.000^a	97.38 (6.76)	100.18 (6.36)	0.000^a	0.818
L1-NB (º)	25.95 (6.23)	29.58 (5.67)	0.000^a	23.67 (6.98)	27.3 (10.23)	0.017^a	0.187
L1-NB (mm)	4.06 (2.23)	5.59 (2.07)	0.000^a	4.06 (2.23)	5.81 (2.21)	0.000^a	0.995
L1-APg (mm)	0.33 (2.15)	2.3 (2.03)	0.000^a	-0.56 (2.38)	2.63 (2.53)	0.000^a	0.134
L1-MP (mm)	30.82 (2.97)	32.64 (3.63)	0.000^a	34.93 (3.12)	34.91 (2.62)	0.002^a	0.000^a
L6-MP (mm)	21.6 (2.47)	23.55 (2.6)	0.000^a	24.95 (2.82)	27.95 (5.07)	0.289	0.000^a
Interdental
Overjet	6.31 (2.74)	4.31 (1.64)	0.000^a	7.65 (2.8)	2.76 (1.44)	0	0.065
Overbite	3.91 (1.93)	2.34 (2.12)	0.001^a	4.3 (2.12)	0.64 (2.1)	0.045^a	0.463
Interincisal angle (U1-L1) (º)	126.75 (10.87)	122.69 (7.57)	0.001^a	126.07 (15.93)	126.51 (10.68)	0.000^a	0.846
Soft-tissue profile
Nasolabial angle (º)	110.12 (8.95)	109.72 (9.41)	0.000^a	119.47 (9.99)	119.50 (12.35)	0.027^a	0.000^a
Nasal projection (mm)	11.64 (1.66)	12.61 (1.86)	0.000^a	12.33 (3.1)	13.83 (2.04)	0.001^a	0.291
Lower lip to E-plane (mm)	0.69 (2.89)	0.34 (2.75)	0.000^a	-0.59 (2.99)	-1.41 (2.85)	0.000^a	0.097
Upper lip to E-plane (mm)	0.39 (1.92)	-1.31 (1.91)	0.000^a	-0.91 (2.92)	-3.22 (2.88)	0.001^a	0.047^a
Upper lip anterior (ULA-Sn) (mm)	2.3 (1.83)	1.86 (2.13)	0.000^a	0.26 (3.03)	0.06 (2.64)	0.004^a	0.003^a
Lower lip anterior (LLA-Sn) (mm)	-3.62 (2.65)	-2.86 (3.08)	0.000^a	-6.59 (5)	-4.26 (4)	0.007^a	0.006^a
Soft tissue A point’ (A’-Sn) (mm)	-1.01 (1.17)	-1.49 (1.36)	0.000^a	-1.97 (2.19)	-2.17 (1.92)	0.03^a	0.04^a
Soft tissue B point’ (B’-Sn) (mm)	-11.73 (2.89)	-11.35 (3.47)	0.000^a	-15.26 (6.6)	-12.03 (5.43)	0.07^a	0.01^a
Soft tissue pogonion (Pg’-Sn) (mm)	-9.8 (3.21)	-9.31 (4.47)	0.000^a	-13.8 (7.65)	-11.33 (6.77)	0.008^a	0.012^a
Soft tissue convexity (º)	127.42 (3.92)	127.9 (4.27)	0.000^a	125.07 (10.35)	126.4 (8.6)	0.518	0.251

^aStatistically significant at level P < 0.05 (Paired samples t-test).
^bComparison of initial cephalometric measurements between monoblock and twin-block groups.
S = sella; N = nasion; A = A Point (subspinale); B = B point (supramentale); SNA = sella-nasion-A point angle; SNB = sella-nasion-B point angle; ANB = A point-nasion-B point angle; Na Perp = nasion perpendicular; Pg = pogonion; Gn = gnathion; FH = Frankfurt horizontale; Go = gonion; PP = palatal plane; MP = mandibular plane; Art = articulare; Me = menton; ANS = anterior nasal spine; Co = condylion; Mx/Md dif = maxillomandibular difference; PFH = posterior facial height; AFH = anterior facial height; OCP = occlusal plane; U1 = incisal edge of the maxillary incisor; L1 = incisal edge of the mandibular incisor; U6 = maxillary first molar; L6 = mandibular first molar; NF = nasal floor; Sn = subnasale; ULA = upper lip anterior; LLA = lower lip anterior; A’ = soft tissue subspinale; B’ = soft tissue supramentale; Pg’ = soft tissue pogonion.