Since a high prevalence of back anomalies has been reported among subjects with crossbite, the aim was to assess the degree of back symmetry among subjects with (crossbite) and without (control) unilateral functional crossbite during the pre-pubertal growth phase. A group of 70 subjects (36 boys, 34 girls; 6.8 ± 1.2 years) in the primary or mixed dentition phase were included. Clinical assessment of head posture, shoulder, scapula and hip height were performed with the subject standing, and differences between the left and right side greater than 5 mm recorded. Asymmetry of the scapula and trunk prominence greater than 8 mm was recorded along with the prominence of thoracic and lumbar paravertebral musculature during the forward-bending test. Back symmetry was assessed qualitatively and quantitatively on colour deviation maps of superimposed mirrored three-dimensional back scans at a tolerance level of 2 mm. No significant differences were observed between the groups regarding the frequency of clinically assessed back anomalies. The percentage of back symmetry was slightly lower in the crossbite than that in the control group (71.4 ± 13.3% and 79.2 ± 12.1%, respectively). A significant association (P ( 0.05) was seen between scapula plane inclination (OR = 3.41) and scapula prominence inequalities (OR = 3.29) and unilateral functional crossbite, while hip height inequalities (OR = 0.94) were more frequent in the control group. No associations were detected between the side of crossbite and side of prominence of back parameters. Although some degree of back asymmetry was detected in the crossbite group during the pre-pubertal growth phase, this asymmetry does not appear to be clinically relevant.
COBISS.SI-ID: 33949657
A full description of the developped methodology for three-dimensional assessment of back asymmetry is presented. In particular, surface back acquisition with a sterephotogrammetric camera (ArtecTM MHT 3D Scanner (Artec 3D, Luxembourg), which uses the flying triangulation method to capture a three-dimensional surface was presented. This single-camera handheld device requires moving the camera around the subject's back at a distance of 70-100 cm, and it is suitable for scanning of larger surfaces with undercuts. The total scanning time of a child's back surface ranges, depending on its size from approximately 27 seconds (smaller backs) to approximately 55 seconds (larger backs) with a reported manufacturing accuracy of 0.1 mm. Surface processing as well as the determination of reference points are described. Moreover, the possibility of different tolerance level selection for qualitative and quantitative analysis and its impact on asymmetry detection are presented. Furthermore, angular measurements on the back surface as well as the modalities od assessment of back areas with greater or smaller prominence, differences between the left and right side and calculation of the percentage of asymmetry of the whole back and its separate areas are presented.
COBISS.SI-ID: 33664473
The protocolos and preliminary results of the clinical assessment of back anomalies among children with and without unilateral functional crossbiteare presented. The asymmetry at the shoulder level was detected in 35% of chlidren with functional crossbite, in the scapula region in 50%, while in the pelvis region the asymmetry was detected in 7.5% of children with crossbite. The prevalence of deviations of the locomotor system (such as neck deviations, shoulder, scapola or pelvis prominence, leg lenght inequalities) were not significantly more frequent in children with unilateral functional crossbite as compared to children without it. However, face asymmetry was predominant in the crossbite group.
COBISS.SI-ID: 33665241
Multiple backward logistic regressions were used for estimates of the association of the presence of a unilateral functional crossbite with each explanatory variable (age, sex, body mass index and either clinical, 3D qualitative and 3D quantitative postural parameters). For model 1, including clinical postural parameters as explanatory variables, sex (male) and inclined scapula plane were negatively and positively associated with the presence of a unilateral functional crossbite with adjusted ORs of 0.262 and 3.41, respectively. For model 2, including 3D qualitative postural parameters as explanatory variables, body mass index, and asymmetrical scapula prominence were positively associated with the presence of a unilateral crossbite with adjusted ORs of 1.41 and 3.29, respectively. For model 3, including 3D quantitative postural parameters as explanatory variables, body mass index, and hip height inequality were positively and negatively associated with the presence of a unilateral crossbite with adjusted ORs of 1.37 and 0.94, respectively. The R2 for models 1, 2, and 3 were low as 0.191, 0.141, and 0.173, respectively. No significant interactions, even considering the unadjusted p- values were seen between the side of the crossbite and any of the postural parameters, with the exception of the neck musculature prominence. Among subjects with unilateral functional crossbite, asymmetries of the scapula prominence were more frequent. No significant differences were detected regarding the degree of asymmetry between the upper, middle, and lower parts of the back.
COBISS.SI-ID: 34530265
The objectives of this study were to assess the three-dimensional (3D) treatment changes (palatal surface area and volume) of forced unilateral posterior crossbite correction using either quad-helix or removable expansion plate appliances in the mixed dentition, and to compare the treatment changes with the three-dimensional changes occurring in age-matched untreated unilateral posterior crossbite patients as well as in subjects with normal occlusion and with no or mild orthodontic treatment need. One-hundred and thirty-five patients with unilateral posterior crossbite with functional shift were recruited. The patients were randomized into the following five groups: quad-helix treatments in specialist orthodontic clinics (QHS), quad-helix treatments in general dentistry (QHG), removable expansion plate treatments in specialist orthodontic clinics (EPS), removable expansion plate treatments in general dentistry (EPG), and untreated crossbite (UC). Twenty-five patients with normal occlusion who served as normal controls were also included in the trial. Data on all children were evaluated on an intention-to-treat basis, regarding 3D palatal surface area, palatal projection area, and palatal shell volume; two-dimensional linear measurements were registered at the same time. After treatment, the surface and projection area and shell volume increased in the four treatment groups (QHS, QHG, EPS, and EPG). QHS increased significantly more than EPG for the surface and projection area. The QHS and EPS had significantly higher mean difference for shell volume.After treatment, there were no significant differences between the four treatment groups and the normal group, which implies that the surface and projection area together with the shell volume for the four treatment groups and the normal group were equivalent.
COBISS.SI-ID: 34451929