In recent years, there has been increasing interest in the relationship between dental occlusion and body posture both among people and in scientific literature. The aim of the present longitudinal study is to investigate the effects of an experimental occlusal interference on body posture by means of a force platform and an optoelectronic stereophotogrammetric analysis. An occlusal interference of a 0- to 2-mm-thick glass composite was prepared to disturb the intercuspal position while not creating interference during lateral or protrusive mandibular excursions. Frontal and sagittal kinematic parameters, dynamic gait measurements and superficial electromyographic (SEMG) activity of head and neck muscles were performed on 12 healthy subjects. Measurements were taken 10 days before the application of the occlusal interference, and then immediately before the application, the day after it, and at a distance of 7 and 14 days under four different exteroceptive conditions. The outcomes of this study show that an occlusal interference does not modify significantly over time static and dynamic parameters of body posture under different exteroceptive conditions. It has a minimal influence only on the frontal kinematic parameters related to mandibular position, and it induces a transient increase of the activity of masticatory muscles. In this study, the experimental occlusal interference did not significantly influence the body posture during a 14-day follow-up period.