Abstract
Abstract
Background
Maintaining static postural sway as well as load distribution is an essential component of overall physical stability in older age. The temporomandibular system is a measurable influencing factor due to functional interdependencies, although it has not yet been sufficiently investigated with regard to sex- and age-specific differences. This cross-sectional analysis therefore aims to examine the association between occlusion, mandibular mobility and static postural sway as well as load distribution in men aged 51 to 60, taking into account body mass index (BMI) and mandibular mobility.
Methods
A total of 98 healthy men, aged between 51 and 60 years (mean age: 55.9 ± 2.72 years), volunteered for the study. Their mean BMI was 27.01 ± 3.91 kg/m² (mean height: 1.81 ± 0.07 m; mean weight: 88 ± 14.13 kg). BMI classification was based on WHO criteria. Postural measurements were conducted using a pressure platform. Mandibular movements (laterotrusion, protrusion and mouth opening) were recorded using an axiograph. Additionally, a model analysis according to Schopf was performed (midline deviation, supporting zone, and transverse width differences in the maxilla and mandible on both the right and left; occlusion of the canines [3s] and first molars [6s] on both sides; overjet; and overbite). The significance level was set at 5%.
Results
Dental model analysis revealed that no participant was classified as Angle Class I, (mean overjet 3.93 mm and mean overbite 3.44 mm). All subjects exceeded the normal ranges defined by the Schopf classification, and the majority (75%) presented with Angle Class II.
No significant association was found between BMI and static postural sway and well as load distribution in the overall analysis (p > 0.05).
BMI subgroup analysis: In the normal-weight group, occlusion of the right first molar (6) exhibited a modest positive correlation with ellipse area (p ≤ 0.01), while occlusion of the right canine (3) exhibited a modest positive correlation with frontal sway (p ≤ 0.01). In the pre-obese group, only a weak negative correlation was observed between occlusion of the right first molar (6) and forefoot load (p ≤ 0.01). In the obese group, occlusion of the right canine (3) showed a strong positive correlation with rearfoot load (p ≤ 0.01) and right laterotrusion showed a significant correlation with sagittal sway (p ≤ 0.02; moderate). Mandibular mobility subgroups in relation to BMI: in participants with hypomobile mouth opening, BMI correlated positively with frontal sway (p ≤ 0.03, strong). In the group with normal right laterotrusion, increasing BMI was associated with significant increases in frontal and sagittal sway, as well as ellipse parameters (p ≤ 0.01–0.05; all weak). In individuals with hypermobile mandibular function, BMI showed a strong negative correlation with occlusion of the first molars (6) in the left forefoot (p ≤ 0.001), as well as a strong positive correlation with the left rearfoot (p ≤ 0.01).
Discussion
While mandibular mobility parameters (laterotrusion, protrusion, mouth opening) were predominantly within normal limits, dental model analysis revealed that the majority (75%) presented with Angle Class II. Additional exploratory subgroup indicated that deviations in canine and molar occlusion were associated with greater body sway and larger sway ellipses. An increased BMI does not appear to directly cause instability but may be associated with, or exacerbate, pre-existing functional limitations or occlusal dysfunctions. Therefore, clinical assessment should adopt a holistic approach that integrates BMI with individual constitutional, occlusal, and functional parameters.