Relationship between different face profiles, jaw positions and static and dynamic balance

The aim research: To determine relationship between different face profiles, jaw positions and static and dynamic balance. Hypotheses: Based on previous research, we believe that the static and dynamic balance of individuals with orthognathic facial profile should be better than that of retrognathic and prognathic facial profile (I); static and dynamic balance should be better at closed mouth than at occlusion or opened mouth (II). Study methods: The study included healthy subjects (n = 27) aged 19 to 35 years with no impairments of temporomandibular joint and balance problems. The subjects first were photographed from the sagittal plane and divided into three groups according to their face profile: group I with the balanced jaw position; group II with the upper jaw protrusion, and group III – with the lower jaw protrusion. The static and dynamic balance was tested in all study participants and at different positions of the jaw: closed mouth, open mouth, and bitten teeth. Results: he static balance of the subjects at different jaw positions did not differ significantly: the total velocity of oscillations was 8,9±1,9 mm/s and the length was 179,1±38,6 mm; with mouth opened – 9,3±2,1 mm/s and 191,3±42,3 mm, with bitten teeth – 9,6±2,1 mm/s and 191,3±42,3 mm. The static balance of the subjects did not differ significantly between the different face profiles: the total speed of osciliations of the orthognathic face profile was 8,22±1,66 mm/s and the length was 164,42±33,28 mm, the retrognathic – 9,24±1,68 mm/s and 184,75±33,63 mm, prognathic – 10,93±3,07 mm/s and 218,63±61,37 mm. The dynamic balance of the subjects at different jaw positions did not differ significantly: the total distance with mouth closed was 84,61±8,35 cm, with open mouth – 85,32±9,19 cm and with bitten teeth – 86,12±8,78 cm. There were no statistically significant differences between dynamic balance and different facial profiles: the total distance at orthognathic face profile was 81,98±5,84 cm, at retrognathic – 85,71±8,77 cm, and at prognathic – 88,90±12,02 cm. Conclusions: The majority of subjects were identified with a retrognathic (63%) facial profile, significantly less with orthognathic (22%) and prognathic (15%) facial profiles. No statistically significant differences were found between static and dynamic balance and three different jaw positions, as well as between static and dynamic balance and three different facial profiles