Dental malocclusion and body posture in young subjects: a multiple regression study

Influence of the mandibular position on various postural anatomical segments

OBJECTIVE

To determine postural changes in relation to mandibular position in maximum intercuspation and at rest in adult patients of both sexes.

METHODS

: A descriptive observational clinical study was carried out in 76 patients. Using an analyzer and the Meersseman test, the necessary dermal points for postural analysis were located.

RESULTS

: The authors found significant differences in the posture adopted by the patient between maximum intercuspation and mandibular rest in the frontal, sagittal, and dorsal planes. Foot support in the right foot went from cavus to normal in 6% of the sample, and from flat to normal in 2.5% of the sample in the jaw rest position.

CONCLUSION

Postural changes were observed in various segments, with clinical and statistical significance at cervical level in the frontal plane, in the biscapular variable in the dorsal plane, and at the level of the lower limbs in the bipopliteal and bimalleolar variables.

Impact of occlusal proprioception on static postural balance

Conflicting results on the effects of occlusal proprioceptive information on standing sway have been reported in the literature, partly due to the heterogeneity of the occlusal criterion studied and the experimental protocol used. In this study, occlusal functions, different mandibular positions and visual conditions were used to investigate the involvement of occlusal proprioception information in static postural balance. Postural adjustments of 26 healthy young adults, divided into Class I malocclusion and Class I normocclusion groups, were studied in upright position, in five mandibular positions (1 free, 2 centric and 2 eccentric), with and without vision. Due to different reported test durations, postural parameters were examined for the first and last halves of the 51.2 s acquisition time. A permutation ANOVA with 4 factors was used: group, mandibular position, vision, time window. Mean length of CoP displacement was shorter with vision (ES = 0.30) and more affected by vision loss in the free than in the intercuspal mandibular position (ES = 0.76 vs. 0.39), which has more tooth contacts. The malocclusion group was more affected by vision loss (ES = 0.64). Unexpectedly, with vision, the mean length was smaller in one eccentric occlusion side compared to the other (ES = 0.51), but independent of the left or right side, and more affected by vision loss (ES = 1.04 vs. ES = 0.71). The first-time window of the acquisition time, i.e. 25.6 s, was sufficient to demonstrate the impact of dental occlusion, except for the sway area. Comparison of the two visual conditions was informative. With vision, the weight of occlusal proprioception was not strictly related to occlusal characteristics (number of teeth in contact; centered or eccentric mandibular position), and it was asymmetrical. Without vision, the lack of difference between groups and mandibular positions suggested a sensory reweighting, probably to limit postural disturbance.

The Effect of Asymmetrical Occlusion on Surface Electromyographic Activity in Subjects with a Chewing Side Preference: A Preliminary Study

The relationship between asymmetrical occlusion and surface electromyographic activity (sEMG) in people with different chewing preferences is not clear. In this study, the 5 s sEMG changes in the masseter muscle (MM), sternocleidomastoid (SCM), lateral (LGA), and medial (MGA) gastrocnemius muscles were recorded in controls, and subjects with chewing side preference (CSP) during clench with bilateral (BCR), left (LCR), and right (RCR) posterior teeth placement of cotton rolls. The images of the middle 3 s were selected and expressed as the root mean square (unit: μV/s). The EMG waves of bilateral muscles were compared by computing the percentage overlapping coefficient (POC). Only the POCMM of the CSP showed gender differences at BCR and RCR. Between the control group and the CSP group, there were significant differences in the POCMM and the POCLGA at BCR. In addition, there was a significant difference in POCMM and POCSCM between the two populations in different occlusal positions. The change in the POCSCM correlated with the change in the POCMM (r = 0.415, p = 0.018). The experiment-induced asymmetrical occlusion showed that the altered symmetry of the MM correlated with the altered symmetry of the SCM. Long-term asymmetrical occlusion (i.e., CSP) not only affects MM but also has potential effects on other superficial muscles (e.g., LGA).

Dental Malocclusion in Mixed Dentition Children and Its Relation to Podal System and Gait Parameters

BACKGROUND

Dental malocclusion is an increasingly frequent stomatognathic disorder in children and adolescents nowadays. The purpose of this study was to confirm or deny the correlations between body posture and malocclusion.

METHODS

In the study, gait, distribution of foot pressure on the ground, and body balance were examined. The research group consisted of 76 patients aged 12-15 years. The research group was obtained from patients attending periodic dental check-ups at Healthcare Center Your Health EL who agreed to participate in the study. The patients were divided into two groups without malocclusion and with malocclusion, using Angle classification, which enabled determination of the anteroposterior relationship of the first molars. The pedobarographic mat was used to analyze the distribution of foot forces on the ground, the diagnostic system Wiva^® Science was used for gait analysis, and Kineod 3D was used for posture analysis. The Shapiro-Wilk test used for analysis showed inconsistency with normal distribution for all measurement parameters. The Mann-Whitney U test was used for the analysis, and the significance level was set at p ≤ 0.05.

RESULTS

Examination of the relationship between stabilometric and gait parameters showed that the position of the mandible in relation to maxilla has an important effect on gait rhythm, gait cycle duration, and right step duration time. Patients diagnosed with malocclusion showed high-speed walking rhythm in comparison to patients with Angle's class I (p = 0.010). The duration of the whole gait cycle (p = 0.007) and the duration of right step (p = 0.027) were prolonged in students without orthodontic disorders compared to the other.

CONCLUSIONS

The conducted study proved that there is correlation between the presence of a stomatognathic disorder and gait cycle parameters. There is a statistically noticeable correspondence between the position of the mandible in relation to maxilla and walking rhythm, gait cycle duration, and right step duration time. Namely, students who presented malocclusion had a high-speed walking rhythm and decreased duration of the gait cycle and of the right step. On the other hand, students without disorders (Angle's class I) showed low-speed rhythm and increased duration of the gait cycle and of the right step in comparison to Angle's classes II and III.

Is There a Correlation between Dental Occlusion, Postural Stability and Selected Gait Parameters in Adults?

Background: There is still an ongoing debate about the role of the craniomandibular system, including occlusal conditions, on postural stability. This study aims to assess the role of antero-posterior malocclusion on postural control and plantar pressure distribution during standing and walking. Methods: 90 healthy volunteers (aged 19 to 35) were qualified for the study. The subjects were assigned to three groups, depending on the occlusion type. Each group (Angle Class I, II and III) consisted of 30 people. The research procedure included a clinical occlusal assessment performed by a dentist. Postural control measurements were carried out using a force platform by measuring plantar pressure distribution during standing (six trials with and without visual control) and walking test conditions. Results: The tendency to shift the CoP forward is demonstrated by Angle Class II subjects and backwards by Class I and III subjects (p < 0.001). Individuals with a malocclusion demonstrated significantly higher selected stabilographic parameters while standing on both feet (with eyes open and closed) and during the single-leg test with eyes open (p < 0.05). The analysis of the dynamic test results showed no significant correlations between Angle Classes and the selected gait parameters. Conclusions: Analyses conducted among individuals with malocclusions showed the impact of occlusion on static postural stability. In order to diagnose and effectively treat malocclusion, a multidisciplinary approach with the participation of dentists and physiotherapy specialists is necessary, with the use of stabilometric and kinematic posture assessments.

Influence of occlusion and mandibular position on foot support and head posture in adult patients

OBJECTIVE

To study postural changes, taking into account different mandibular positions and the cephalic and plantar body segments.

METHODS

A cross-sectional, descriptive, clinical, and observational study was carried out on 76 patients, (mean age 28.79 years), in whom body posture and plantar support were evaluated in the maximum mandibular intercuspal position and the mandibular rest position without dental contact.

RESULTS

When the mandibular position was altered, 71.01% of the patients showed changes in the bipupillary line (p = 0.008), while those who did not show such changes did, however, show changes in plantar support. More than 85% of the sample experienced alterations in the plantar plane when the mandibular position was changed, with statistically significant results (p < 0.001).

CONCLUSION

There is a positive relationship between the different segments in body posture. In the sample, changes in plantar support with respect to the different mandibular positions were noticeable.

Does head and cervical posture correlate to malocclusion? A systematic review and meta-analysis

BACKGROUND

The association of head and cervical posture with malocclusion has been studied for many years. Despite extensively encouraging researches, no conclusive evidence has been reached for clinical application.

OBJECTIVE

To identify the question "Does head and cervical posture correlate to malocclusion?", a systematic review and meta-analysis based on the available studies were carried out (PROSPERO registration number: CRD42022319742).

METHODS

A search of PubMed, Embase, Cochrane Library, and the grey literature was performed without language restrictions. The study screening, data extraction, risk-of-bias evaluation and methodological quality assessment were performed by two independent investigators. When a disagreement arose, a third author was consulted.

RESULTS

6 original cross-sectional studies involving 505 participants were included, which were of moderate methodological quality. NL/VER in Class Ⅱ group and NL/CVT in Class Ⅲ group showed significant differences compared to Class Ⅰ group, but no significant differences were observed in most of the variables like NSL/VER, OPT/CVT, OPT/HOR, CVT/HOR, NSL/OPT, NSL/CVT, NL/OPT in Class Ⅱ and Ⅲ groups.

CONCLUSIONS

The results suggested that the current research evidence is not sound enough to prove the association of head and cervical posture with sagittal malocclusion. Better controlled design and a larger sample size are required for clarifying this question in future study.

Relationship between back posture and early orthodontic treatment in children

Background

The purpose of this study was to analyze the relationship between body posture and sagittal dental overjet in children before and after early orthodontic treatment with removable functional orthodontic appliances.

Methods

Angle Class II patients (mean age 8.2 ± 1.2 years; 29 males and 25 females) with a distinctly enlarged overjet (> 9 mm) were retrospectively examined regarding body posture parameters before and after early orthodontic treatment. In addition, changes in overjet were investigated with the aid of plaster models. Forms of transverse dysgnathism (crossbite, lateral malocclusions) and open bite cases were excluded. Body posture parameters kyphosis, lordosis, surface rotation, pelvic tilt, pelvic torsion and trunk imbalance were analyzed by means of rasterstereographical photogrammetry to determine, if the orthodontic overjet correction is associated with specific changes in posture patterns.

Results

In nearly all patients an overjet correction and an improvement regarding all body posture and back parameters could be noted after early orthodontic treatment. Overjet reduction (− 3.9 mm ± 2.1 mm) and pelvic torsion (− 1.28° ± 0,44°) were significantly (p < 0.05) and moderately correlated (R = 0.338) with no significant associations found for the other posture and back parameters (p > 0.05).

Conclusion

Overjet reduction during early orthodontic treatment may be associated with a detectable effect on pelvic torsion.

Influence of dental occlusion conditions on plantar pressure distribution during standing and walking - A gender perspective

The aim of this study was to investigate gender-specific influences of different symmetric and asymmetric occlusion conditions on postural control during standing and walking. The study involved 59 healthy adult volunteers (41 f/19 m) aged between 22 and 53 years (30.2 ± 6.3 years). Postural control measurements were carried out using a pressure plate by measuring plantar pressure distribution during standing and walking test conditions. Seven different occlusion conditions were tested. Prior to a MANOVA model analysis, the relationship between the two test conditions were checked using a factor analysis with a varying number of factors (between 2 and 10). The plantar pressure distributions during walking and standing are independent test conditions. The coefficient of variance across all variables between the conditions and genders was not significant: t(46) = 1.51 (p = 0.13). No statement can be made whether, or not, the influence of gender is greater than the influence of the conditions. Healthy male and female test subjects did not show any difference between seven occlusion conditions on the plantar pressure distribution while standing or walking. No differences between the genders were found for any of the investigated variables. In contrast to custom-made occlusion splints, simple cotton rolls appear not to influence the neuromuscular system in a systematic manner.

Dental Malocclusion and Its Relation to the Podal System

Background and Objective: This study analyzes the possibility that Stomatognathic and Postural systems are related by muscle chains. Malocclusion may influence the posture, contact between the foot and the ground, center of mass, footprint or vice-versa. This study aimed to verify whether there is a relationship between dental occlusion and podal system. Materials and Methods: A cross-cutting, descriptive study was carried out on 409 children (222 boys and 187 girls) between 8 and 14 years old. Dental occlusion was assessed on the sagittal plane (Angle's classification) the contact between the foot and the ground and the center of mass were evaluated using a stabilometric platform. Results: There was a statistically significant relationship between the plantigrade phase, the contact surface area and center of gravity. There was a prevalence of molar and canine Angle's class II malocclusion. In molar class II, an anterior center of gravity was predominant, in class I it was centered and in class III, it was posterior. There was significant correlation between malocclusions and the FPI (foot posture index) of the left foot and the height of the scaphoid in the right foot (P < 0.001). Conclusions: Some authors agree with our results. There is still much uncertainty in terms of showing a relationship between both systems. In addition, there is scarce scientific evidence on the topic. Some kind of relationship between the two systems has been proven. Studies that evaluate a group of subjects in a longitudinal manner are necessary to enable the changes taking place in both systems to be defined.

Influence of Dental Malocclusion on Body Posture and Foot Posture in Children: A Cross-Sectional Study

The number of studies that investigate the correlations between the temporomandibular system and body posture, postural control, or the distribution of plantar pressure has recently been increasing. However, most of the existing information is not conclusive. Therefore, the study objective was to evaluate if the features of dental malocclusion are correlated with body posture alterations at the lower limb level. This is a multicentre cross-sectional study with 289 children (8-14 years). Angle's molar relation was analysed at the dental level. The postural control and the plantar pressure distribution were recorded via a force platform. Correlation and inferential analysis between the Angle class and the foot's biomechanics were tested. The centre of gravity is anteriorised in Angle's Class II in both the molar class (p ≤ 0.001) and the canine class (p ≤ 0.001). Likewise, a relationship was observed between the contact surface and Angle's classes, being higher in class III than in II (p ≤ 0.001). The plantigrade phase is shortened in Angle's Class III. A relationship was found between Angle's Class II and a forward movement of the centre of gravity. No relationship was found between the Foot Posture Index and the truncated scaphoid height and the dental classification. An evident relationship between the gait typology and dental malocclusion was not found.

The correlation between back posture and sagittal jaw position in adult orthodontic patients

Objective

A debate remains in evidence-based medicine about the reciprocal interchange between dental occlusion and body postural therapy. Back posture deformity has been found to be related to trunk asymmetry as one characteristic of scoliosis that is commonly reported in occlusal development issue. This study aims to determine the correlation between back posture and sagittal jaw position in adult orthodontic patients treated at the dental hospital of Universitas Sumatera Utara.

Methods

This observational study was conducted on orthodontic patients who had routine orthodontic control between October 2019 and February 2020. The sagittal jaw relationship on pre-treatment cephalometry lateral-based on Steiner analysis was done with OrthoVision software. The back posture that related to cervical, thoracic, and lumbar measurement was performed using scoliometer plastic economy (Baseline®).

Results

From 128 patients, aged between 18 and 30 years, we found 72 patients with Class I, 41 patients with Class II, and 15 patients with Class III skeletal malocclusion. There were no significant differences of trunk asymmetry based on sagittal jaw relationship (p = 0.651). Additionally, there was no significant correlation between back posture and sagittal jaw position in Class II and Class III patients (r = 0.112, p > 0.05).

Conclusion

In this study, the sagittal jaw relationship had poor correlation to back posture in orthodontic adult patients due to a compensatory mechanism. The presence of temporomandibular dysfunction, sella-nasion-B point, and head posture are specific variables in a particular dento-skeletal type that should be considered in further studies.

Association between constitution, axiography, analysis of dental casts, and postural control in women aged between 41 and 50 years

Objectives

The aim of this study was to investigate the relationship between anamnestic, axiographic and occlusal parameters and postural control in healthy women aged between 41 and 50 years.

Materials and methods

A total of 100 female participants aged between 41 and 50 (45.12 ± 2.96) years participated in the study. In addition to completing a general anamnesis questionnaire, lower jaw movements were measured axiographically, dental occlusion parameters were determined using a model analysis and postural parameters were recorded using a pressure measurement platform. The significance level was 5%.

Results

An increasing weight and a rising BMI lead to a weight shifted from the rearfoot (p ≤ 0.01/0.04) to the forefoot (p ≤ 0.01/0.02). A limited laterotrusion on the right resulted in a lower forefoot load and an increased rearfoot load (p ≤ 0.01). Laterotrusion to the left (extended above the standard) showed a lower frontal sway (p ≤ 0.02) and a reduced elliptical area, height and width (p ≤ 0.01, 0.02, 0.03). Thus, the extent of deviation correlated with reduced right forefoot loading (p ≤ 0.03) and the extent of deflection correlated with increased left foot loading (p ≤ 0.01). The higher the extent of angle class II malocclusion, the larger the ellipse area (p ≤ 0.04) and the ellipse height (p ≤ 0.02) resulted.

Conclusions

There is a connection between weight, BMI and laterotrusion, as well as between angle class II malocclusion and postural control in women aged between 41 and 50 years. Interdisciplinary functional examinations of mandibular movements treating possible limitations can be conducive for an improvement of postural control.

Clinical relevance

Angle class II malocclusion has a negative influence on postural control.

Bridging the gap between temporomandibular disorders, static balance impairment and cervicogenic dizziness: Posturographic and clinical outcomes

Several studies have investigated the possible influence of temporomandibular disorders (TMD) on body posture and whether cervical spine disorders, such as cervicogenic dizziness (CGD) could play an additional role in affecting static balance. The purpose of this study was to analyze static postural behavior by means of static posturography, in patients affected by either TMD or CGD alone or by both conditions, and to compare findings with a group of healthy subjects. Significant changes in posturographic parameters were found among the three groups of patients and when compared with controls. When the three study groups were compared to each other, subjects affected by a combination of TMD and CGD showed worse postural performances with respect to subjects affected by CGD or TMD alone. Correlations with self-perceived dizziness, anxiety, depression and jaw functionality, investigated by means of validated questionnaires, were found among all patient groups. These results provide new evidences for the presence of static balance alterations in patients suffering from TMD with and without associated cervical spine impairment, by using a reliable diagnostic technique. Further studies are needed in order to identify any causal relation between these two disorders.

Relationship between Unilateral Posterior Crossbite and Human Static Body Posture

Background: We compared photogrammetry-assessed body posture between young adults with and without unilateral posterior crossbite (UPCB). Assessments were controlled by vision, mandibular position and sitting/standing position. In addition, we aimed to determine the relationship between UPCB laterality and the direction of body posture using photogrammetry and a static postural platform. Methods: Adults with natural dentition, with and without UPCB, were enrolled. Static body posture was assessed by photogrammetry based on horizontal acromial alignment and horizontal anterior-superior iliac spine (ASIS) alignment. Frontal photographs were taken with participants asked to open or close their eyes and hold their jaws at rest, at an intercuspal position, and at left or right lateral positions. Distribution of foot pressure was recorded using a static postural platform at different visual input and mandibular positions. General linear models with repeated measures were used to assess the effect of the various within- and between-subject factors. Results: In total, 36 adults (left UPCB = 12; Right UPCB = 6; controls = 18) participated. There were significant differences between the control and UPCB groups in horizontal alignment at the acromion (p = 0.035) and ASIS (p = 0.026) levels when controlled by visual input and mandibular position. No significant differences in horizontal alignment or foot pressure distribution were observed by laterality in the UPCB group. Conclusion: The presence of UPCB affects static body posture, but the side of crossbite is not related to the direction of effect on static body posture.

Vibrotactile -Feedback Device for Postural Balance Among Malocclusion Patients

Multiple studies have suggested that some associations exist between occlusal factors and postural alterations. Objectives: This study aimed to evaluate the effectiveness of a vibrotactile posture trainer device, comprised a wearable device containing an accelerometer sensor to measure the angle of the neck flexion (input) and provided real-time vibrotactile biofeedback (output) for postural balance among patients with malocclusion. Methods: Twenty-four subjects were divided in 3 groups based on occlusion and using Angle’s classification. Each group consisted of 8 patients for class I, II and III malocclusion. The Posture Trainer System was used for feedback concerning neck flexion angles when higher than 15 degrees. A 4-week training program to adjust posture balance in 2 axes (flexion-extension, lateral-flexion) was applied in activities for daily living. The assessments in this study were comprised of neck flexion angles from the Posture Trainer System and the center of pressure (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{upgreek} \usepackage{mathrsfs} \setlength{\oddsidemargin}{-69pt} \begin{document} }{}$\text{N}\cdot \text{m}$ \end{document}) using a force plate. The effects of a vibrotactile posture trainer (baseline vs. post-training test) were evaluated using the paired t-test and were assumed to be significant at p < 0.05 (two-side). All analyses were conducted using the Statistical Package for Social Sciences, Version 21.0 (SPSS, Chicago, IL, USA). Results: Neck flexion angles and center of pressure significantly decreased post-training by the Posture Trainer System among patients with class II malocclusion. No changes in the above parameters post-training were found in class I and class III. Conclusion: The results demonstrated that patients with class II malocclusion training by the Posture Trainer System lowered neck flexion angles and COP compared with pre-training. Clinical Impact: Feedback by the Posture Trainer System can help improve the postural balance in class II malocclusion.

Association between constitution, medical history, axiography and postural control in women aged between 21 to 30 years

The aim of this study was to determine association between constitutional, medical history and axiographic parameters with postural control parameters. Overall, 106 healthy female subjects aged between 21 and 30 years were measured. Data collection was carried out by completing a questionnaire on constitutional parameters, illnesses, accidents and medical/orthodontic therapies, as well as by axio- and posturographic measurements. Data were analyzed using correlations, pair comparisons and group comparisons. The significance level was set at p ≤ 0.05. The statistical evaluation showed significant correlations between sporting exercise and body sway in the sagittal direction (p ≤ 0.03), the BMI and the load on the forefoot/rear foot (p ≤ 0.01), the mouth opening and the load on the forefoot/rearfoot (p ≤ 0.01) and the presence of a deviation with the load on the left/right foot (p ≤ 0.01). The physical condition as well as the temporo-mandibular system are associated with the postural control in young women. Therefore, a holistic diagnosis and therapy will be supported by the present outcomes.

[Assessment of postural control and balance in persons with temporomandibular disorders: A systematic review]

The stomatognathic system is the anatomo-functional unit of the cranio-cervico-facial region. Some dysfunctions affect its motor control. The aim of this study was to analyse the clinical usefulness of the various scales and instruments used in the assessment of postural control in people with temporomandibular disorders. A systematic review was carried out by 2independent reviewers in the PubMed, Medline, Ebsco, Science Direct and PEDro databases, selecting observational studies published between January 2006 and March 2017. The risk of bias and methodological quality was analysed following Cochrane indications and the Downs and Black quality scale. Ten studies were included, of which 9used computerised platforms, one added photogrammetry and one used electromyography. Seven studies were classified as moderate quality and 3as low quality. Posturography was the most widely used assessment instrument. Methodological differences did not allow determination of their clinical implications or the relationship between balance and the presence of temporomandibular disorders.

Analysis of Dental Malocclusion and Neuromotor Control in Young Healthy Subjects through New Evaluation Tools

The presence of a correlation between stomatognathic and postural systems has been investigated by different authors trying to identify a possible influence of dental occlusion on body posture and balance. The aim of this study was to evaluate the relationship between dental occlusion and neuromuscular control in a healthy young population using modern evaluation tools. 25 subjects (9 males and 16 females, aged 23 to 44) were evaluated for dental occlusion, particularly in relation to overjet and overbite parameters, anterior and posterior crossbite, scissor bite, mandibular crowding, molar and canine class, and deviation of the median dental line. Neuromotor control was assessed using two different types of stabilometric platforms in both monopodalic and bipodalic equilibriums (Prokin-B and MF-Stability, Tecnobody, Italy). All subjects were evaluated with and without cotton rolls positioned between the upper and lower arches at the premolar level in order to temporarily eliminate any pathological contact. In all 25 subjects, no statistically significant differences were revealed between the evaluations performed with and without cotton rolls in all the analyzed conditions (in static, in dynamics, with open and closed eyes). This study did not find a significant correlation between dental occlusion and neuromuscular control in a young and healthy population.

Influence of dental occlusion on the athletic performance of young elite rowers: a pilot study

OBJECTIVES

The present study aimed to assess the influence of dental occlusion on body posture and the competitive performance of young elite rowers.

METHOD

Dental occlusion disturbance devices were used to simulate dental malocclusions. We assessed the influence of malocclusion on the body balance, paravertebral muscle contraction symmetry, and muscular power of young elite rowers. A nonparametric permutation test for repeated measures ANOVA, a Cochran's Q test for paired data and a paired Student's t-test were used in order to statistically evaluate the influence of artificial occlusal disturbance on each factor. A force platform and a Dyno Concept 2 machine were used as measuring instruments.

RESULTS

A total of 7 members of the "Pôle France Aviron" (age range of 15-17 years) were enrolled in the study. None of the body balance parameters was significantly influenced by the artificial occlusal disturbance. The interposition of an occlusal silicone splint significantly increased the proportion of athletes presenting asymmetric muscular contractions from 14.3% to 85.7% (p=0.025) and induced a significant 17.7% decrease in the athletes' muscular power (p=0.030).

CONCLUSIONS

This study shows the negative impacts of an occlusal disturbance on the athletic performance of young elite rowers. The detection of malocclusion traits by regular occlusal monitoring would be of great interest in this population.

Does occlusal splint affect posture? A randomized controlled trial

OBJECTIVE

The aim of this study was to evaluate the effect of an occlusal splint on body posture of intra-articular temporomandibular joint (TMJ) disorders patients.

METHODS

The study was performed on 45 women affected by TMJ disorders divided into an occlusal splint group and a control group. Rasterstereographic recordings were performed at baseline and after 1, 3, and 6 months, in order to analyze the following postural parameters: trunk inclination, cervical and lumbar arrows, kyphotic and lordotic angles, trunk imbalance, pelvic tilt and torsion.

RESULTS

Regarding the postural parameters in the intragroup analysis, no significant differences were detected. The analysis between the two groups revealed significant differences concerning the cervical arrow, the kyphotic and lordotic angles.

DISCUSSION

Even if some differences were found between the control and the occlusal splint group, the low range of statistical significance made these results not significant from a clinical point of view.

Is PostureScreen® Mobile app an accurate tool for dentists to evaluate the correlation between malocclusion and posture?

OBJECTIVE

To determine whether PostureScreen® Mobile app is a useful, simple tool that is accessible for dentists to evaluate the correlation between malocclusion and posture.

METHODS

Twenty-nine subjects underwent static and dynamic dental occlusion examinations and a postural exam with PostureScreen® Mobile app, a photographic method. The subjects were divided into groups depending on their static and dynamic occlusion features. The postural parameters were then compared between these groups.

RESULTS

Statistically significant differences (p < 0.05) for some postural parameters were obtained for Angle Class 1 vs. 2 and 3 and for the passive interference group and active premature contacts group during left lateral movement. There were no statistically significant differences regarding protrusion and right lateral movement.

DISCUSSION

Dental occlusion anomalies and posture pathological modifications can be inter-related. PostureScreen® Mobile app might represent a useful tool in the early diagnosis of dental occlusion pathology.

Effect of Treatment with Twin-Block Appliances on Body Posture in Class II Malocclusion Subjects: A Prospective Clinical Study

Background

There is strong evidence that malocclusion and body posture are interdependent. The relationship between improvement of nasopharyngeal airway, correction of malocclusion by orthodontic treatment or orthognathic surgery, and changes in body posture were evaluated in several studies. The purpose of the present study was to analyze the effect of the orthodontic treatment with Twin-block appliance on body posture.

Material/Methods

The study group consisted of 23 children (mean age 12.45 (1.06) years). They were orthopedically (back shape analysis) and orthodontically (cephalometric radiograph analysis) examined before the treatment with Twin-block appliance and 10–14 months after the beginning of treatment.

Results

Treatment with Twin-block appliance caused mandibular protrusion as SNB increased by 0.91°, distance Ar-B increased by 4.9 mm, ANB decreased by 0.15°; and increase of face height. Oropharynx airway increased by 1.54 mm and deep pharynx airway by 1.08 mm. The decrease in kyphotic, lordotic, craniocervical angles, upper thoracic, pelvic, and trunk inclinations was found to be statistically significant. When comparing orthopedic measurements between study and control groups, no differences were detected. The control group also showed reduction of all measured angles. Although the decrease of kyphotic angle, upper thoracic inclination, trunk inclination, and craniocervical angle were more pronounced in the study group, the differences were not significant.

Conclusions

Based on these results, the body posture changes during treatment with Twin-block appliance were an expression of the physiological growth, not a response to improvement in occlusion.

Short-Term Repeatability of Stabilometric Assessments

The authors evaluated the short-term (within-day, between-days) repeatability of center of pressure (COP) displacements. COP sway area and speed were obtained in the morning and afternoon of two separate days, both with open (EO) and closed (EC) eyes, in 10 healthy adults. Agreement and variability among conditions were tested by ANOVA and Bland-Altman plots. Mode (EO/EC, area: p = .032; speed: p < .004), and day (day1/day2, area: p = .006; speed: p = .02) showed significant differences. The EC condition and the second test day showed the largest values, with medium-large effect sizes. Time-of-day did not influence COP displacements. Speed had better agreement than area (Bland-Altman plots). COP displacements were well reproducible within-day, but had significant between-days variations. COP assessments should be performed in the same session.

Gait changes after using a temporomandibular joint exerciser in patients who underwent lower limb joint surgery

[Purpose] The improvements in gait of the patients with lower limb disease who used a temporomandibular joint (TMJ) exerciser were verified. [Subjects and Methods] Eleven subjects were included. Their mean age was 53.2 years. The lower limb joint angles before and after using the TMJ exerciser were measured using a gait analyzer. Before the gait experiment, the TMJ exerciser setting process and one-leg stance balance test (OLST) were repeated until the balance maintenance time improved. [Results] Because of the OLST, the mean change in the body center point after the subjects used the exerciser improved from 5.76 mm to 4.20 mm. When the TMJ exerciser was used, the joint angle range of the subjects approached that of the normal individuals. [Conclusion] According to the gait experiments, the angles of the subjects' hips, knees, and ankle joints approached to those of the normal individuals after the subjects used the TMJ exerciser; however, the results did not completely match. The changes in the hip, knee, and ankle joint angles were statistically significant, which confirm the usefulness of the TMJ exerciser.

Effects of experimental insoles on body posture, mandibular kinematics and masticatory muscles activity. A pilot study in healthy volunteers

BACKGROUND

It has been hypothesized that different plantar sensory inputs could influence the whole body posture and dental occlusion but there is a lack of evidence on this possible association.

OBJECTIVES

To investigate the effects of experimental insoles redistributing plantar pressure on body posture, mandibular kinematics and electromyographic (EMG) activity of masticatory muscles on healthy subjects.

METHODS

A pilot study was conducted on 19 healthy volunteers that wore custom-made insoles normalizing the plantar pressure distribution for 2 weeks. Body posture parameters were measured by means of an optoelectronic stereophotogrammetric analysis; mandibular kinematics was analyzed by means of gothic arch tracings; superficial EMG activity of head and neck muscles was performed. Measurements were carried out 10 days before the insertion of the insoles, immediately before the insertion, the day after, 7 and 14 days after, in four different exteroceptive conditions.

RESULTS

The outcomes of the present study show that insoles do not modify significantly over time the parameters of body posture, SEMG activity of head and neck muscles and mandibular kinematics.

CONCLUSIONS

In this pilot study the experimental insoles did not significantly influence the body posture, the mandibular kinematics and the activity of masticatory muscles during a 14-day follow up period.

One-leg standing time with eyes open: comparison between the mouth-opened and mouth-closed conditions

OBJECTIVE

Many studies report a significant relationship between the one-leg standing time with the eyes open and the occlusal relationship. To determine the association between proprioception (the periodontal membrane vs muscle spindle) to the one-leg standing time, the authors compared the one-leg standing time with eyes open between mouth-opened and mouth-closed conditions.

METHODS

The study participants were 107 healthy, elderly patients. The authors measured the one-leg standing time with eyes open between mouth-opened and mouth-closed conditions.

RESULTS

The one-leg standing time was significantly shorter with the mouth opened (21·1±19·1 seconds) than with the mouth closed (25·1±21·4 seconds). Patients whose one-leg standing time was equal or shorter with the mouth opened than with the mouth closed were not different from the other patients with regard to age, handgrip strength, BMI, and the number of remaining teeth.

DISCUSSION

The vertical mandibular position may affect body balance.

Craniocervical posture and trigeminal nerve mechanosensitivity in subjects with a history of orthodontic use: a cross-sectional study

The purpose of the study was to evaluate whether, in asymptomatic subjects, there are differences in: (i) head posture while sitting and standing still and (ii) trigeminal nerve mechanosensitivity, between those who have a history of using orthodontics and those who do not. The sample consisted of 72 subjects (21 +/- 2.14 years): one group who had used orthodontics in the past (n = 37), and another group who had not had previous orthodontic treatment (n = 35). The authors measured the CranioVertebral Angle (CVA) while the subject was sitting and standing still by means of lateral photographs, and the pressure pain threshold (PPT) of the trigeminal nerve. The orthodontics group showed a more upright position of the head when sitting compared to the non-orthodontics group, with the difference being statistically significant (ANOVA test; p < 0.001; F1,70 = 16.705; R2 = 0.19), but not for the standing position (p = 0.538). The values of the PPT in the trigeminal nerve (supraorbital-V1, infraorbital-V2 and mandibular-V3) were lower on both sides (dominant and nondominant) in the non-orthodontics group. The between-group comparison (ANOVA test) showed statistically significant differences for the trigeminal nerve PPT in its different branches (V1 p = 0.001; F1,70 = 13.012; R2 = 0.15) (V2 p = 0.004; F1,70 = 9.103; R2 = 0.11) (V3 p = 0.005; F1,70 = 8.228; R2 = 0.10). Based on these observations, it was concluded that subjects with a history of orthodontic use show a better sitting craniocervical posture and mechano-sensitivity of the trigeminal nerve branches compared to the group that had not used orthodontics in the past.

A correlational study of scoliosis and trunk balance in adult patients with mandibular deviation

Previous studies have confirmed that patients with mandibular deviation often have abnormal morphology of their cervical vertebrae. However, the relationship between mandibular deviation, scoliosis, and trunk balance has not been studied. Currently, mandibular deviation is usually treated as a single pathology, which leads to poor clinical efficiency. We investigated the relationship of spine coronal morphology and trunk balance in adult patients with mandibular deviation, and compared the finding to those in healthy volunteers. 35 adult patients with skeletal mandibular deviation and 10 healthy volunteers underwent anterior X-ray films of the head and posteroanterior X-ray films of the spine. Landmarks and lines were drawn and measured on these films. The axis distance method was used to measure the degree of scoliosis and the balance angle method was used to measure trunk balance. The relationship of mandibular deviation, spine coronal morphology and trunk balance was evaluated with the Pearson correlation method. The spine coronal morphology of patients with mandibular deviation demonstrated an "S" type curve, while a straight line parallel with the gravity line was found in the control group (significant difference, p<0.01). The trunk balance of patients with mandibular deviation was disturbed (imbalance angle >1°), while the control group had a normal trunk balance (imbalance angle <1°). There was a significant difference between the two groups (p<0.01). The degree of scoliosis and shoulder imbalance correlated with the degree of mandibular deviation, and presented a linear trend. The direction of mandibular deviation was the same as that of the lateral bending of thoracolumbar vertebrae, which was opposite to the direction of lateral bending of cervical vertebrae. Our study shows the degree of mandibular deviation has a high correlation with the degree of scoliosis and trunk imbalance, all the three deformities should be clinically evaluated in the management of mandibular deviation.

Clinical association between teeth malocclusions, wrong posture and ocular convergence disorders: an epidemiological investigation on primary school children

Background

As the various systems in the body are inter-connected to form a single structural unit, a pathological condition in one area can also affect other areas. There are many known correlations between the visual and motor system. The importance of visual function, particularly the paracentral peripheral field of view, in motor coordination, ambulation and the maintenance of balance has been amply demonstrated.

In line with current medical principles, which are moving towards a more holistic view of the human body, this study aims to investigate, in an interdisciplinary manner, the incidence of dental malocclusions together with posture and eye convergence disorders.

Methods

Six hundred and five children attending at the 3^rd, 4^th and 5^th years of seven Genoa primary schools were examined. Each child underwent the following examinations: (i) dental/occlusal; (ii) orthoptic; and (iii) postural. Occlusal data concerned the presence of cross-bite, midline deviation with a mandibular shift, bad habits and deep or open bite.

Postural assessment involved frontal and lateral inspection, investigation during trunk flexion and ambulation, and note of any asymmetry in the lower limbs. The recorded orthoptic data included those pertaining to ocular dominance, a cover test, convergence and the Brock string test.

Results

A prevalence of cases with an unphysiological gait was found in patients with overjet (14.70%) or overbite (14.87%), while the percentage of patients with normal occlusion that showed an unphysiological gait was 13.08%. Also, about 93.8%–94.2% of children showed normal legs without dysmetry, with no difference in respect to the type of occlusion. Subjects with an open bite or deep bite showed a slightly different distribution of right or left dominant eyes.

Conclusion

About 13% of children showed a pathological gait and, among them, vertical anomalies of occlusion (deep bite or open bite) were prevalent with respect to the other occlusal defects. The vertical dimension of occlusion revealed a slight relationship with the proper dominant eye. Postural, orthoptic, osteopathic and occlusal variables were often clinically associated, and therefore these disorders appear to request a multidisciplinary medical approach for their treatment.

The Stomatognathic System's Role in the Postural Stabilization in Subjects Suffering from Whiplash Injury Part 1: Patients with Physiological Occlusion

Aim of this study is analyze the effects of dental occlusion on postural stability in patients with previous whiplash and normal occlusion. Materials and methods: 36 adult patients with previous whiplash and normal occlusion (good alignment, 1st class or mild 2nd class deep bite for mandibular retrusion) were selected. The patients were suffering from masticatory muscles pain caused by clenching during sleep. Exclusion criteria: use of psych drugs. To simulate the conditions of sleep (with a reduction of proprio-and esteroceptive inputs for postural management performed by CNS), we used postural Romberg analysis (feet together, closed eyes)on stabilometric platform changing occlusal parameters only, under the following conditions: 1) in occlusal rest position, 2) in centric occlusion, 3) in clenching, 4) with occlusal disengage with cotton rolls and 5) in clenching on cotton rolls. Time of each test: 15 seconds. It was performed a statistical analysis with T-test comparing between them the mean of all tests. Results: stabilometry data (postural ball and ellipse) show better postural performances in centric occlusion and clenching in centric occlusion, and a worsening in all tests with occlusal disengage (with statistically significant difference - p<0.05). Conclusions: postural instability caused by whiplash increases muscles tone and dental clenching as compensatory effects, with onset of facial pain. An occlusal disengage (like an occlusal splint to reduce clenching)induces a postural worsening in patients with normal occlusion, while centricocclusion increases the stability. These results suggest that stomatognathic organ has a new physiological function: the posture stabilization.

Do malocclusion and Helkimo Index ≥ 5 correlate with body posture?

Whether there are correlations between the stomatognathic system and body posture remains controversial. Here, we have investigated whether malocclusal traits and having a Helkimo Index ≥ 5 show detectable correlations with body-posture alterations in children and young adults. A total of 1178 11- to 19-year-old subjects were divided into four groups: (i) controls; (ii) malocclusion; (iii) Helkimo Index ≥ 5 and (iv) malocclusion + Helkimo Index ≥ 5. Dental occlusion assessment included the following: overbite, overjet, posterior crossbite, scissorbite, mandibular crowding and dental class. Subsequently, body-posture assessments were performed through static analyses of body inclination and trunk asymmetry, and according to the dynamic Fukuda stepping test. Univariate and multivariate statistical analyses were performed. Although at the univariate level both the trunk asymmetry and Fukuda stepping test showed significant differences among the groups, the multivariate level revealed that age and gender were mostly responsible for this. The only significant correlation that was seen was for the malocclusion + Helkimo Index ≥ 5 group: these subjects had a positive (worse) trunk asymmetry and a negative (better) Fukuda stepping test performance. At the further multivariate analyses of each single malocclusal trait ⁄Helkimo Index ≥ 5 (irrespective of the groups), only an increased overbite showed a statistically significant association with a slightly better Fukuda stepping test performance. Given the small number of significant associations seen and their limited entities, this study does not support the existence of clinically relevant correlations for malocclusal traits and Helkimo Index ≥ 5 with body posture in children and young adults.

Estudo de publicações brasileiras em periódicos gerais de artigos sobre aparelho locomotor

Sào estudados os perfis de publicação de artigos relacionados ao aparelho locomotor em duas revistas médicas brasileiras gerais indexadas. Os autores estudam o perfil de publicação de artigos com registro no PUBMED, em um período de dois anos. Selecionados 39 artigos com distribuição heterogênea entre as revistas estudadas. Observaram-se nítida progressão no número de artigos entre os anos estudados em ambas as publicações, principalmente em Clinics. Entre as áreas de interesse os artigos referentes a cirurgia, abordagens clínicas e estudos biomecânicos tiveram expressiva presença em Clinics. Na RAMB os estudos estiveram centrados exclusivamente na área de interesse clínico. Quanto ao desenho predominaram em Clinics ensaios clínicos, revisões e séries de casos. Na RAMB Houve predomínio de séries de casos, revisões e estudos diagnósticos

Inclinação de cabeça durante a mastigação habitual nas deformidades dentofaciais classe II e III

OBJETIVO: este estudo investiga a diferença entre grupos com deformidade dentofacial (padrão classe II e classe III), em relação à preferência mastigatória referida e inclinação de cabeça durante a mastigação, assim como predomínio intra-grupo de cada um desses aspectos, comparativamente a um grupo controle. MÉTODOS: participaram deste estudo, voluntariamente, 25 pacientes (entre 18 e 35 anos). Doze pacientes com diagnóstico de deformidade dentofacial classe II e 13 pacientes com o diagnóstico de classe III esquelética e 10 voluntários, com equivalência em sexo e idade ao grupo de deformidade, formando o grupo controle. Os voluntários da pesquisa foram questionados sobre a existência de um lado de preferência mastigatória. Em seguida foram filmados durante a mastigação habitual de um biscoito maizena e através das imagens captadas, a postura de cabeça pôde ser analisada. RESULTADOS: não houve diferença entre os grupos em relação à preferência mastigatória referida, entretanto os grupos com deformidades dentofaciais apresentaram predomínio significativo de preferência mastigatória referida. Os grupos com deformidade dentofacial apresentaram maior predomínio de inclinação de cabeça durante a mastigação quando comparados ao grupo controle. CONCLUSÃO: indivíduos com deformidade dentofacial podem apresentar uma preferência mastigatória e alteração de postura de cabeça durante a mastigação.