Changes in the craniofacial structures and esthetic perceptions of soft-tissue profile alterations after distalization and Herbst appliance treatment

Introduction

The purpose of this prospective clinical trial is to evaluate the changes of soft tissues and designate the esthetic perceptions of children with Class II malocclusion after Herbst appliance therapy and maxillary molar distalization using stereophotogrammetry.

Methods

Thirty patients were allocated either to Herbst (6 boys and 9 girls; mean age = 11.60 ± 0.82 years) or distalization (4 boys and 11 girls; mean age = 11.46 ± 1.30 years) groups. Dentoskeletal and soft-tissue treatment changes were examined objectively by cephalometric analysis and stereophotogrammetry, respectively. Pre- and posttreatment profile views were evaluated subjectively by orthodontists and laypeople using the 7-point Likert scale. Intra- and intergroup comparisons for the repeated measurements were performed with 2-way variance analysis. Bonferroni test was used for multiple comparisons ( P ≤0.05).

Results

Greater skeletal changes were observed in the Herbst group than in the distalization group. Maxillary incisor retrusion and mandibular incisor protrusion were observed in the distalization and Herbst groups, respectively. Stereophotogrammetric measurements showed that mandibular body length and lower and anterior facial height increased in both treatment groups. Convexity angle ( P = 0.020) and labiomental angle ( P = 0.033) were greater in the Herbst group than the distalization group.

Conclusions

The skeletal contribution to correction of maxillomandibular discrepancy was greater in the Herbst group than the distalization group. Significant profile improvements were recorded for both groups with treatment. After both treatments, orthodontists were found to have higher rates of detection in the profiles than laypeople. The esthetic contribution of treatments to the facial profile was found similar in both groups.

Highlights

  • Treatment effects of Herbst appliance and molar distalization appliances were compared.

  • Cephalometric and stereophotogrammetric measurements were performed.

  • A jury rated profile photographs to evaluate and compare improvements in 2 groups.

  • Greater skeletal changes were observed in the Herbst group.

  • Neither treatment was superior to the other, according to raters.

Functional appliance therapy and distalization are used for the treatment of Class II malocclusions, although their mechanism of action differs. Researchers evaluating the long-term effects of functional treatments argue that the permanent effect has been seen on the midface at the end of treatment. Bowman noted that the changes obtained with the treatment of Class II malocclusions were dentoalveolar and that the mandibular response was the same when interfering with the maxilla or mandible. However, the idea of treating the “wrong jaw” is contradictive among clinicians who mainly desire to observe maxillary or mandibular effects.

However, the human face is complex, and some simple lines and angles are not always enough to evaluate this structure. The baseline expectation of most patients is esthetic improvement, and profile views are used to evaluate it. Hence, the importance of evaluating patient perceptions of profile attractiveness has increased in the literature. , In a study by Sloss et al, orthodontists (Os) and laypeople (LP) assessed changes in the profiles of patients treated with Herbst and headgear using silhouettes, and the scoring of the profiles provided by both appliances at the end of treatment was found to be similar.

Janson et al evaluated lateral cephalograms of late pubertal patients with Class II malocclusion and found that fixed functional appliances presented similar soft-tissue results as 2 maxillary premolar extraction treatments.

Barroso et al evaluated the ability of Os and LP to discriminate mandibular stepwise advancements in Class II retrognathic mandible on photographs. They suggested that considering the mean of sagittal mandibular growth is 2 mm owing to the use of functional appliances, that LP may not be able to discriminate this small amount of change in facial-profile attractiveness. However, both Os and LP were able to distinguish 4- and 6-mm stepwise advancement of the mandible.

do Rego et al noted that after early Herbst appliance treatment, positive changes to facial profile were visually appreciable both immediately after the treatment and 2 years after the appliance removal according to both Os and LP. Almeida studied profile attractiveness with manipulated photographs using Adobe Photoshop (version C2; Adobe Systems, San Jose, Calif). They produced from each original face a straight profile, retrusion, and protrusion. All the raters showed agreement that the straight profile is the most attractive.

The soft-tissue paradigm forms the basis for the orthodontic treatment planning of teeth and facial skeleton. Currently, one of the most popular applications for recording and analysis of soft tissues is stereophotogrammetry. It is a system that combines the images taken in and received by 1 or more pairs of cameras simultaneously to obtain soft-tissue recordings and creates a 3-dimensional (3D) image. It has a short screening time, no side effects, and is easy to use for clinicians. Ayoub et al evaluated the stereophotogrammetry technique and concluded that the results are acceptable in terms of reliability and consistency.

Our study aimed to evaluate the alteration of facial soft tissues in growing patients with Class II Division 1 mandibular retrognathia after functional treatment and molar distalization using stereophotogrammetric measurements objectively and examining changes in profile esthetics subjectively. Because soft tissue is affected by the position of dentoskeletal structures, the changes in the hard tissues were also evaluated.

Material and methods

Thirty patients were included in this study, based on the study by Burkhardt et al. Findings from the multivariate analysis of variance indicated that at least 80% statistical power necessitated a minimum sample size of 15 in each group to detect a significant difference between the groups.

The 30 growing patients were divided into 2 groups. The Herbst group consisted of 6 males and 9 females, with a mean age of 11.60 ± 0.82 years, whereas the distalization group consisted of 4 males and 11 females, with a mean age of 11.46 ± 1.30 years. The treatment duration was 11.73 ± 1.39 months and 14.60 ± 0.51 months for the Herbst and distalization groups, respectively.

Ethical approval for this study was obtained from the Ethical Committee of Izmir Katip Çelebi University (no. 91). The parents of the subjects included in this study signed informed consent forms.

Late-mixed or early-permanent dentition, depended mandibular retrognathia (SNB <78°), skeletal Class II relationship (ANB >4°), angle Class II molar relationship, <4 mm crowding in dental arches (according to model analysis), and vertically normal growth (25°< SN-GoGn <39°) were the inclusion criteria for this study. In contrast, systemic disease, orthodontic treatment history, congenital tooth defect or permanent tooth extraction, severe facial asymmetry, and poor oral hygiene were the exclusion criteria.

Mandibular incisor proclination, gingival thickness, gingival height, palatal bone thickness, and palatal depth were also evaluated during treatment planning. Treatment assignment for patients was determined on the basis of diagnostic criteria provided by 1 orthodontist (A.B). Patients matching the criteria were included in the appropriate treatment group (without randomization), after evaluation of intraoral and extraoral photographs, plaster casts, and radiographs.

Furthermore, the efficacy of Herbst and distalization treatments on hard tissue was evaluated with cephalometric radiographs, whereas differences in soft tissue were evaluated using 3D facial scans.

Lateral cephalometric radiographs were obtained in a natural head position, with teeth in centric occlusion and lips in a rest position. To analyze cephalometric radiographs, we determined 35 landmarks and created 14 planes. A total of 39 measurements, including 20 skeletal, 16 dental, and 2 soft-tissue measurements were performed using Dolphin Imaging software (version 11.8; Dolphin Imaging and Management Solutions, Chatsworth, Calif).

In this study, the 3dMD face imaging system (3dMD Inc., Atlanta, Ga) was used to obtain 3D images, and 3dMD Vultus software (3dMD) was used to process and measure images. Face scans were captured in a digital recording studio designed as a separate section in the clinic to ensure minimal patient interaction with the outside. The records were taken in a natural head position, which was repeatable. Patients were told to release facial muscles, swallow, and look into their own eyes in a mirror placed between the cameras with eyes open.

The scanning time lasted approximately 1.5 ms. After the face scan, the records were examined using 3dMD viewer software (3dMD Inc.). The process was repeated if the face scan result was below the ideal image quality. Three-dimensional images were processed to remove confounding regions by clipping the extraneous surface data from the neck, ears, and scalp hair ( Fig 1 ).

Fig 1
Processed images by clipping the extraneous surface data from the neck, ears, and scalp hair.

The acrylic-splint Herbst design was used, with the Type IV Herbst (Dentaurum, Ispringen, Germany) telescope system. There was a limited amount of side movements during the opening and closing movements of the jaw and chewing. The base pieces were soldered to a 1-mm-diameter wire sculpture formed on the model in which they were located on the buccal side of the maxillary first molars and the mandibular first premolars. Hyrax screws were added to the upper splints to prevent upper jaw constriction. The maxillary splint was covered with acrylic from the mesial side of the canine to the distal side of the molars, whereas the mandibular splint was extended from the distal sides of the first molars ( Fig 2 ).

Fig 2
Acrylic-splint Herbst appliance design.

The maxillary splints were cemented with glass ionomer cement (3M ESPE, Ketac Cem Easymix, Dentsply DeTrey GmbH, Konstanz, Germany) in all patients, and the mandibular splints were removable to ensure good oral hygiene. The use of the appliance continued until the super Class I molar relationship was achieved and overjet eliminated. After the active Herbst appliance therapy, a monoblock-type retention device was delivered to the patient to obtain good interdigitation and stable mandibular position. The total treatment time for the Herbst group was 11.73 ± 1.39 months.

In distalization group, the appliances used in the study are supported only by miniscrews. Under local anesthesia, 3-mm predrilling was performed before the mini-implant application. The screws have a total length of 11.6 mm and a diameter of 2 mm and consist entirely of titanium (The Aarhus System Miniscrews; American Orthodontics, Tuttlingen, Germany). The screws were placed 3-6 mm to the right and left of the sutura palatina media bilaterally in the transversal plane and posterior to the third palatinal ruga in the sagittal plane.

After selecting appropriate bands for the maxillary first molar teeth, the impression was made with alginate. A stainless steel sliding tube with a diameter of 0.9 mm was bent and placed in the palatal sides of molar bands. The distalization arch with a 1-mm-diameter stainless steel wire was twisted around the screws and passed through the sliding tubes. In the mesial side of the first premolars, solder was used on the arch to act as a stopper. An open coil spring was placed between the sliding tube and the stopper to apply 240 g of distalization force. Miniscrews and distalization arch were fixed to each other with composite material (3M Unitek, Monrovia Calif) ( Fig 3 ). If an occlusal interference was detected between maxillary and mandibular teeth, a mandibular removable appliance was delivered to the patient to enable molar distalization.

Fig 3
Miniscrew-supported intraoral distalization appliance.

Patients were given appointments at 4-week intervals. The activation was achieved with crimpable stoppers placed to the distal side of solders. Thus, the desired force was maintained. After Class I molar relationship was obtained, anterior teeth were bracketed, and a 17 × 25-inch beta-titanium utility arch was applied for retraction. Premolar teeth were not bracketed to allow distal movement through transseptal fibers. After obtaining the ideal overjet, the anterior brackets were removed, and all records taken initially from the patients were repeated. The mean duration of treatment was calculated as 14.6 ± 0.51 months.

The 3dMD Vultus analysis program was used to analyze the 3D data (3dMD). In the program, 3D images were placed in appropriate and standard positions in 3 dimensions of the space before the points were determined. The reference points are marked after the reference planes have been created on the 3D facial image ( Fig 4 , A and B ).

Fig 4
A, The reference points created on the 3D facial image (front). B, The reference points. created on the 3D facial image (profile).

Linear, angular, and proportional analyses were performed after the points were marked in the 3D face scan.

Profile images of the patients were taken before and after treatment from standardized images in the 3dMD Vultus program. All images were standardized in size, and each numbered between 1 and 60. The presentation and evaluation of the profiles were done similar to the study by Mergen et al. The study included 2 groups of 10 persons, who were at least in the fourth year of being an orthodontic assistant or Os and LP. In terms of being familiar with the profiles, 5 descriptive images were recorded in our clinic but not included in the study and presented to the evaluators. The 60 profile images included in the study were presented to the evaluators in the same order, with intervals of 10 seconds. The attractiveness of photographs was then scored using a Likert scale between 1 and 7 (1 = lowest, 7 = highest).

Statistical analysis

The measurements on all cephalometric radiographs and 3dMD images were repeated after 1 month to determine the reproducibility of the measurements used in this study. Repeated measures were assessed using intraclass correlation coefficients. If the intraclass correlation coefficient was >85%, we determined that there was no method error.

All statistical evaluations were performed using the SPSS statistical software (version 22; IBM, Armonk, NY). Levene and Shapiro-Wilk tests were used to evaluate the normal distribution and homogeneity of the data. Normal distribution of the data was observed, and parametric tests were used. Two-way analysis of variance was used for repeated measurements in intragroup and intergroup comparisons. Bonferroni test was used for multiple comparisons.

To evaluate the level of agreement between rates, we computed the Kendall coefficient of concordance (Kendall’s W) separately for all rater groups considering the initial and final scores. The statistical significance level was determined as P ≤0.05.

Results

Interclass correlation coefficients were calculated to evaluate the method error. A correlation of ≥85% was found between repeated measurements. The minimum and maximum coefficients were between 0.893 and 0.996 for cephalometric measurements and 0.861 and 0.994 for soft-tissue measurements.

When the initial (T0) cephalometric values of the study groups were compared, the only statistically significant differences were found for Wits appraisal ( P = 0.05) and overbite ( P = 0.028) ( Table I ).

Table I
Comparison of initial cephalometric values between groups
Measurements Herbst (T0) Distalization (T0) Mean difference P
Maxillary measurements
SNA (°) 81.82 ± 3.45 81.92 ± 3.03 −0.10 ± 1.18 0.933
Co-A (mm) 81.44 ± 4.46 79.42 ± 3.50 2.01 ± 1.46 0.181
N⊥FH-A (mm) −2.30 ± 3.11 −2.46 ± 3.23 −0.16 ± 1.15 0.891
N-CF-A (°) 58.13 ± 3.20 57.78 ± 2.41 0.35 ± 1.03 0.736
FH-NA (°) 92.45 ± 3.31 92.65 ± 3.45 −0.20 ± 1.23 0.873
Mandibular measurements
SNB (°) 75.42 ± 2.72 75.73 ± 2.46 −035 ± 0.91 0.701
Co-Gn (mm) 101.01 ± 7.06 99.25 ± 3.30 1.76 ± 2.01 0.390
Go-Gn (mm) 69.04 ± 5.79 66.08 ± 5.85 2.96 ± 2.12 0.175
N⊥FH-Pog (mm) −4.46 ± 4.51 −4.38 ± 4.52 −0.08 ± 1.65 0.962
Maxillomandibular measurements
ANB (°) 6.41 ± 1.84 6.14 ± 2.18 0.27 ± 0.73 0.714
CoGn-CoA (mm) 19.56 ± 3.85 19.83 ± 2.64 −0.26 ± 1.20 0.827
Wits appraisal (mm) 5.56 ± 1.88 3.56 ± 1.73 2.00. ± 0.66 0.005
Vertical measurements
SN-GoGn (°) 31.49 ± 3.33 33.50 ± 3.81 −2.01 ± 1.30 0.135
GoGn-FH (°) 20.86 ± 2.87 22.77 ± 3.95 −1.91 ± 1.26 0.141
SN-PP (°) 8.29 ± 2.60 8.83 ± 2.61 −0.54 ± 0.95 0.576
PP-Mp (°) 26.50 ± 2.91 28.02 ± 3.33 −1.52 ± 1.14 0.193
Inner angle sum (°) 394.81 ± 3.45 396.84 ± 3.54 −2.02 ± 1.27 0.124
y-axis (°) 58.12 ± 2.36 58.43 ± 2.95 −0.30 ± 0.97 0.756
S-Go (mm) 67.06 ± 5.01 72.81 ± 4.50 2.23 ± 1.45 0.136
ANS-Me (mm) 59.60 ± 6.49 59.40 ± 2.74 0.20 ± 1.82 0.913
Interdental measurements
U1-L1 (°) 118.38 ± 6.29 118.82 ± 7.70 −0.44 ± 2.56 0.863
Overjet (mm) 6.56 ± 1.42 5.98 ± 1.16 0.57 ± 0.47 0.237
Overbite (mm) 5.34 ± 0.96 4.28 ± 1.48 1.06 ± 0.45 0.028
Maxillary dentoalveolar measurements
SN-U1 (°) 110.89 ± 7.78 108.70 ± 6.45 2.18 ± 2.61 0.410
PP-U1 (°) 119.18 ± 5.44 117.53 ± 4.08 1.64 ± 2.48 0.512
U1-NA (°) 29.07 ± 5.98 26.79 ± 5.99 2.28 ± 2.55 0.379
U1-NA (mm) 5.97 ± 2.75 4.77 ± 2.38 1.20 ± 0.94 0.213
U1⊥PP (mm) 25.97 ± 2.88 25.68 ± 1.81 0.29 ± 0.88 0.741
U6⊥PP (mm) 18.96 ± 2.71 17.99 ± 1.36 0.97 ± 0.78 0.226
U1-MxOP (°) 49.86 ± 5.03 50.40 ± 5.32 −0.54 ± 1.89 0.777
Mandibular dentoalveolar measurements
L1-MdOP (°) 59.80 ± 3.32 61.16 ± 3.57 −1.36 ± 1.26 0.288
IMPA (°) 95.93 ± 5.88 95.63 ± 4.70 0.30 ± 1.94 0.879
L1-NB (°) 26.14 ± 4.59 28.24 ± 5.85 −2.09 ± 1.92 0.285
L1-NB (mm) 5.34 ± 1.76 5.87 ± 2.15 −0.53 ± 0.71 0.463
L1-APog (mm) 0.68 ± 1.63 1.75 ± 1.87 −1.07 ± 0.64 0.106
L1⊥Mp (mm) 33.52 ± 3.68 33.46 ± 1.84 0.06 ± 1.06 0.950
L6⊥Mp (mm) 22.92 ± 3.13 23.02 ± 2.27 −0.10 ± 1.00 0.921
Soft-tissue measurements
Lower lip to E-line (mm) −0.32 ± 1.78 0.96 ± 2.93 −1.28 ± 0.88 0.158
Upper lip to E-line (mm) −1.64 ± 1.55 −1.32 ± 2.34 −0.32 ± 0.72 0.657

Note. Values are mean ± standard deviation.

Initial (T0) and final (T1) changes with Herbst treatment are presented in Table II .

Table II
Comparison of cephalometric measurements within and between groups
Measurements Herbst Distalization Group effect Time effect Group × time effect Intergroup treatment effect
T0 T1 T1 – T0 T0 T1 T1 – T0 P P P P
Maxillary measurements
SNA 81.82 ± 3.45 82.01 ± 3.15 0.19 ± 1.36 81.92 ± 3.03 82.60 ± 3.08 0.68 ± 1.82 0.760 0.147 0.410 0.410
Co-A 81.44 ± 4.46 84.75 ± 4.60 3.31 ± 2.86 ∗∗∗ 79.42 ± 3.50 82.04 ± 4.72 2.61 ± 3.33 ∗∗ 0.123 <0.001 0.542 0.542
A-N⊥FH −2.30 ± 3.11 −3.46 ± 3.69 −1.16 ± 1.80 −2.46 ± 3.23 −4.31 ± 3.32 −1.85 ± 3.11 ∗∗ 0.658 0.003 0.462 0.462
N-CF-A 58.13 ± 3.20 59.90 ± 3.72 1.77 ± 2.51 ∗∗ 57.78 ± 2.41 56.96 ± 3.11 −0.82 ± 2.37 0.131 0.295 0.007 0.007
FH-NA 92.45 ± 3.31 93.52 ± 3.73 1.07 ± 1.86 92.65 ± 3.45 94.60 ± 3.55 1.95 ± 3.34 ∗∗ 0.594 0.005 0.381 0.381
Mandibular measurements
SNB 75.42 ± 2.72 77.29 ± 3.30 1.87 ± 1.45 ∗∗∗ 75.73 ± 2.46 76.02 ± 2.36 0.24 ± 1.32 0.632 <0.001 0.003 0.003
Co-Gn 101.01 ± 7.06 107.82 ± 6.08 6.80 ± 3.15 99.25 ± 3.30 100.92 ± 3.73 1.54 ± 3.06 0.070 0.622 0.158 0.008
Go-Gn 69.04 ± 5.79 71.35 ± 6.22 2.31 ± 0.54 ∗∗∗ 66.08 ± 5.85 68.72 ± 5.92 2.64 ± 0.54 ∗∗∗ 0.202 <0.001 0.67 0.670
Pog-N⊥FH −4.46 ± 4.51 −0.20 ± 6.76 −3.30 ± 5.16 ∗∗ −4.38 ± 4.52 −2.02 ± 4.52 −2.53 ± 3.01 0.581 0.004 0.382 0.621
Maxillomandibular measurements
ANB 6.41 ± 1.84 4.72 ± 1.41 1.69 ± 1.34 ∗∗∗ 6.14 ± 2.18 6.59 ± 2.43 −0.45 ± 1.61 0.250 0.030 <0.001 <0.001
CoGn-CoA 19.56 ± 3.85 23.06 ± 3.13 3.50 ± 3.06 ∗∗∗ 19.83 ± 2.64 20.56 ± 3.72 0.72 ± 2.33 0.346 <0.001 0.001 0.001
Wits appraisal 5.56 ± 1.88 1.22 ± 2.61 −4.34 ± 2.42 ∗∗∗ 3.56 ± 1.73 3.74 ± 2.25 0.17 ± 2.10 0.703 <0.001 <0.001 <0.001
Vertical measurements
SN-GoGn 31.49 ± 3.33 31.51 ± 4.49 0.02 ± 2.78 33.50 ± 3.81 34.56 ± 4.20 1.06 ± 2.31 0.077 0.258 0.276 0.276
GoGn-FH 20.86 ± 2.87 19.99 ± 4.60 −0.86 ± 3.13 22.77 ± 3.95 22.58 ± 3.93 −0.19 ± 4.25 0.082 0.444 0.626 0.626
SN-PP 8.29 ± 2.60 8.54 ± 2.51 0.25 ± 1.48 8.83 ± 2.61 8.16 ± 2.83 −0.67 ± 1.91 0.934 0.507 0.150 0.150
PP-Mp 26.50 ± 2.91 25.44 ± 4.37 −1.05 ± 3.49 28.02 ± 3.33 28.92 ± 3.24 0.90 ± 3.39 0.033 0.904 0.132 0.132
Inner angle sum 394.81 ± 3.45 394.00 ± 4.33 −0.81 ± 2.62 396.84 ± 3.54 377.08 ± 3.06 0.24 ± 2.91 0.464 0.310 0.349 0.304
y-axis 58.12 ± 2.36 57.06 ± 3.54 −1.06 ± 2.36 58.43 ± 2.95 57.86 ± 2.31 −0.56 ± 3.97 0.519 0.184 0.683 0.683
S-Go 67.06 ± 5.01 72.81 ± 4.50 5.75 ± 3.59 ∗∗∗ 64.82 ± 2.58 67.24 ± 4.29 2.42 ± 3.02 ∗∗ 0.010 <0.001 0.011 0.011
ANS-Me 59.60 ± 6.49 62.85 ± 7.62 3.25 ± 3.26 ∗∗∗ 59.40 ± 2.74 61.28 ± 3.07 1.88 ± 2.66 0.645 <0.001 0.217 0.217
Interdental measurements
U1-L1 118.38 ± 6.29 121.90 ± 6.79 3.52 ± 5.54 118.82 ± 7.70 123.78 ± 6.70 12.29 ± 9.20 0.775 0.323 0.866 0.004
Overjet 6.56 ± 1.42 2.78 ± 0.42 −3.77 ± 1.48 ∗∗∗ 5.98 ± 1.16 3.10 ± 0.59 −2.88 ± 1.22 ∗∗∗ 0.633 <0.001 0.082 0.082
Overbite 5.34 ± 0.96 3.26 ± 1.08 −2.08 ± 1.44 ∗∗∗ 4.28 ± 1.48 3.50 ± 1.37 −0.78 ± 1.36 0.284 <0.001 0.017 0.017
Maxillary dentoalveolar measurements
SN-U1 110.89 ± 7.78 103.87 ± 4.89 −7.02 ± 6.15 108.70 ± 6.45 90.32 ± 3.25 −12.38 ± 8.07 ∗∗∗ 0.033 <0.001 0.081 0.050
PP-U1 (°) 119.18 ± 5.44 112.42 ± 4.39 −6.75 ± 5.95 117.53 ± 4.08 100.48 ± 3.59 −12.78 ± 8.86 ∗∗∗ 0.040 <0.001 0.056 0.037
U1-NA (°) 29.07 ± 5.98 21.86 ± 3.01 −7.21 ± 6.11 ∗∗∗ 26.79 ± 5.99 16.36 ± 6.42 −12.43 ± 8.78 ∗∗∗ 0.031 <0.001 0.069 0.069
U1-NA (mm) 5.97 ± 2.75 3.59 ± 1.43 −2.38 ± 2.12 ∗∗∗ 4.77 ± 2.38 1.50 ± 2.70 −3.26 ± 2.78 ∗∗∗ 0.035 <0.001 0.335 0.335
U1⊥PP 25.97 ± 2.88 27.56 ± 3.29 1.59 ± 1.67 ∗∗ 25.68 ± 1.81 26.46 ± 1.89 0.78 ± 1.96 0.430 0.001 0.236 0.236
U6⊥PP 18.96 ± 2.71 19.23 ± 2.59 0.26 ± 1.44 17.99 ± 1.36 18.45 ± 1.39 0.46 ± 1.07 0.244 0.131 0.682 0.682
U1-MxOP 49.86 ± 5.03 54.37 ± 3.30 4.51 ± 3.89 ∗∗ 50.40 ± 5.32 62.18 ± 6.45 11.78 ± 6.83 ∗∗∗ 0.014 <0.001 0.001 0.001
Mandibular dentoalveolar measurements
L1-MdOP 59.80 ± 3.32 59.17 ± 5.27 −0.62 ± 4.11 61.16 ± 3.57 61.27 ± 2.23 0.10 ± 2.72 0.166 0.686 0.570 0.570
IMPA 95.93 ± 5.88 100.22 ± 6.55 4.29 ± 4.43 ∗∗∗ 95.63 ± 4.70 95.46 ± 4.67 −0.16 ± 4.57 0.179 0.018 0.011 0.011
L1-NB (°) 26.14 ± 4.59 31.52 ± 4.91 5.38 ± 3.36 ∗∗∗ 28.24 ± 5.85 28.58 ± 4.23 0.34 ± 4.15 0.801 <0.001 0.001 0.001
L1-NB (mm) 5.34 ± 1.76 7.09 ± 1.91 1.75 ± 0.93 ∗∗∗ 5.87 ± 2.15 6.05 ± 1.88 0.18 ± 1.07 0.713 <0.001 <0.001 <0.001
L1-APog 0.68 ± 1.63 3.38 ± 1.45 2.70 ± 1.17 ∗∗∗ 1.75 ± 1.87 1.71 ± 2.02 −0.04 ± 1.64 0.618 <0.001 <0.001 <0.001
L1⊥Mp 33.52 ± 3.68 34.82 ± 3.80 1.30 ± 2.10 33.46 ± 1.84 34.85 ± 2.57 1.39 ± 2.33 0.985 0.003 0.909 0.909
L6⊥Mp 22.92 ± 3.13 25.72 ± 2.79 2.80 ± 1.57 ∗∗∗ 23.02 ± 2.27 24.44 ± 2.16 1.42 ± 1.79 ∗∗ 0.521 <0.001 0.033 0.033
Soft-tissue measurements
Lower lip to E-line (mm) −0.32 ± 1.78 −0.14 ± 1.64 0.18 ± 1.68 0.96 ± 2.93 0.59 ± 2.37 −0.36 ± 1.53 0.198 0.762 0.354 0.354
Upper lip to E-line (mm) −1.64 ± 1.55 −3.80 ± 1.34 −2.15 ± 1.78 ∗∗∗ −1.32 ± 2.34 −1.88 ± 2.20 −0.56 ± 1.57 0.084 <0.001 0.015 0.015
Only gold members can continue reading. Log In or Register to continue

Feb 28, 2021 | Posted by in Orthodontics | Comments Off on Changes in the craniofacial structures and esthetic perceptions of soft-tissue profile alterations after distalization and Herbst appliance treatment
Premium Wordpress Themes by UFO Themes