Three-dimensional assessment of back symmetry in subjects with unilateral functional crossbite during the pre-pubertal growth phase: a controlled study

"Association between posterior unilateral functional crossbite and asymmetrical spinal flexion: A prospective study"

Background

Unilateral posterior crossbite (UPC) with functional shift is a malocclusion that may have the potential to affect the masticatory function and the flexibility of the spine due to intrinsic occlusal, structural and functional asymmetries sustained by marked asymmetrical muscular activation.

Research question

To investigate whether the presence of UPC with functional shift is associated with reverse chewing pattern and altered spine flexion.

Methods

Patients with UPC and a control group of patients with normal occlusion were recorded when chewing soft and hard boluses using a Kinesiograph (Myotronics-Noromed Inc., USA) and spine alignment was assessed with an electronic inclinometer Spinal Mouse® system (Idiag AG, Switzerland).

Results

There were 87 children with UPC in the patients' group among whom 38, with median (IQR) age 8.0 (7.3-9.3) years, had measurements before and after treatment. The UPC patients showed a higher percentage of anomalous/reverse chewing patterns on the crossbite side compared with a control group (p < 0.001). Moreover, a clear difference was observed between left and right flexion angles of the spine in the patients' group (p < 0.001 and p = 0.001, paired t-test) with the crossbite side being more flexible compared to the non-crossbite side. No such differences were seen in the control group, nor post-treatment for right and left crossbite (p = 0.44 and p = 0.15 respectively, paired t-test).

Significance

This study suggests an association between UPC, asymmetrical chewing patterns and asymmetrical flexion of the spine. These results may help improve understanding of any association between dental malocclusions and spine posture and hence aid diagnosis and treatment strategies.

Elastodontic treatment with oral bio-activators in young children

BACKGROUND

Elastodontic therapy can correct bad oral habits and malocclusions in young patients by guiding jaw growth, eliminating functional disorders, and improving tooth position. The aim of this study was to assess the effects of bio-activator therapy on the presence of atypical swallowing with tongue thrust in growing patients.

METHODS

A retrospective study was conducted. Data regarding the early orthodontic treatment of 40 consecutive patients with atypical swallowing and tongue thrust (23 males and 17 females) were assembled from January 2019 to January 2020. All patients (≥7 and ≤15 years of age) were monitored for 1 year in a private practice in Isernia, Italy.

RESULTS

The mean age at commencement of orthodontic treatment was 8.5 years (range=7.1-14.9 years), and the mean total duration of therapy was 1 year (range=11 months-1 year). Final lateral radiographs demonstrated a mean of improvement of 8° for upper and lower incisor proclination (I/SN) and 3.5° for incisor mandibular plane angle (IMPA) in 36 patients, and 5° of I/SN and 2° of IMPA in the remaining 4 children after 1 year of treatment.

CONCLUSIONS

Bad oral habits in younger patients must not be ignored. The duration of treatment can differ depending on the severity of the open bite and the patient's cooperation. This study demonstrates the short-term efficacy of these myofunctional appliances in the treatment of atypical swallowing. In order to quickly eliminate factors which endanger healthy development of dento-skeletal structure, it is important to closely monitor patients during their development phase.