Unilateral Angle II in functional lateralities

Craniofacial Asymmetry from One to Three Years of Age: A Prospective Cohort Study with 3D Imaging

Deformational plagiocephaly (DP) is considered a risk factor for facial asymmetry. This cohort-based, prospective, follow-up study used three-dimensional (3D) stereophotogrammetry to assess the development of facial asymmetry in a normal birth cohort and to investigate the impact of DP on facial asymmetry for the age range of one to three years. The study sample consisted of 75 children: 35 girls (47%) and 40 (53%) boys recruited from Oulu University Hospital. A total of 23 (31%) subjects had a history of DP in infancy. 3D facial images were obtained at the mean (SD) age of 1.01 (0.04) year old at T1 and 3.02 (0.14) years old at T2. To determine facial asymmetry, both landmark-based and surface-based facial symmetry methods were used. As measured with the surface-based methods, upper facial symmetry improved from T1 to T2 (p < 0.05). As measured with the landmark-based methods, facial symmetry improved on the upper and lower jaw from T1 to T2 (p < 0.05). The asymmetric effect of DP on the upper parts of the face tends to correct spontaneously during growth. Results indicate that previous DP does not seem to transfer to facial or occlusal asymmetry at the age of three years old.

Clinical association between dental malocclusion and strabismus in adolescents: a retrospective dental cast analysis

BACKGROUND

The aim of this retrospective study was to evaluate the occlusion in adolescents with strabismus in comparison with healthy subjects without vision problems.

METHODS

The test group included 50 subjects (23 males and 27 females) with a diagnosis of strabismus and the control group included 50 healthy patients (23 males and 27 females) without any past or present disturbance of vision. Dental cast analysis was performed to evaluate antero-posterior, transversal and vertical malocclusion and dental crowding. Furthermore, oral habits (mouth breathing, atypical swallowing, finger sucking) were recorded. Mann-Whitney test was performed in order to evaluate significant differences between the groups regarding overbite, overjet and dental crowding; Kruskal-Wallis non-parametric test was adopted to compare the samples. Chi square test and Fisher test were adopted for the analysis of cross-bite, Angle Class, and oral habits.

RESULTS

No significant difference was found regarding the malocclusion and the unhealthy oral habits between the groups (P>0.05). The test group showed a slightly higher prevalence of cross-bite but the difference between the two groups was not significant (P>0.05).

CONCLUSIONS

A possible relationship between the stomatognathic system and strabismus was not confirmed by the results of this study.

Correlations between the Visual Apparatus and Dental Occlusion: A Literature Review

Background

The development of visual functions takes place in the first months of postnatal life and is completed around the one year of age. In this period, the maturation of the retina and the visual pathways occur, and binocular bonds are established at the level of the visual cortex. During this phase and then for a few years, a certain plasticity of the visual functions remains, which seem therefore susceptible to change both in a pejorative sense (by pathogens) and in an improving sense (for example, by therapeutic measures). This plasticity involves also the oculomotor system. Due to this plasticity, many researchers believe that there are some functional correlations between the visual and the stomatognathic apparatus. But the scientific evidence of this statement has not been clarified yet.

Aim

The purpose of this review is therefore to analyze the clinical data in this field and finally to establish their level of evidence. Studies have been collected from the main databases, based on keywords.

Results

The results showed a middle level of evidence since most of the data derive from case-control studies and cross-sectional studies.

Conclusions

The level of evidence allows establishing that there is a correlation between ocular disorders (myopia, hyperopia, astigmatism, exophoria, and an unphysiological gait due to ocular convergence defects) and dental occlusion, but it is not possible to establish the cause-effect relationship. Future studies should be aimed at establishing higher levels of evidence (prospective, controlled, and randomized studies).

Childhood intelligence and early tooth wear patterns

OBJECTIVE

The aim of this study is to explore the relationships between early dental wear patterns and preschool IQ (Intelligence Quotient, by Stanford-Binet) of the child to illuminate the historic relationship of mental queries and bruxism.

METHODS

The dental study participants were 864 Euro-American preschool and school children whose IQs were tested for school maturity purposes at the age of 4 years, followed by dental data in a cross-sectional manner at the mean age of 7.8 years. Worn dentitions were classified as "symmetric" or "right-" and "left-sided," based on the faceting of the teeth.

RESULTS

In general, the relationships of tooth wear and intelligence were scarce, reflecting social background factors. Statistically significant results between asymmetric wear and gender groups suggest that direction of jaw function has a role in the regulation of processes responsible for individual mental performance in childhood.

DISCUSSION

Increased left-side tooth wear and early advantage in the intelligence test in girls is intriguing due to the fact that they reach maturity earlier than boys in verbal articulation, controlled in most cases by the limited area on the left side of the brain.

Breakages using a unilateral fixed functional appliance: a case report using The Forsus Fatigue Resistant Device

Fixed functional appliances are designed to provide a simple non-compliant solution to orthodontic Class II treatment. Molar correction can be achieved very quickly using these appliances, but the clinician should be wary of unexpected breakages. This case report documents such an occurrence using a unilateral fixed functional appliance.