Sam Melton posted an update 11 months, 3 weeks ago
The film is a pressure-sensitive RG 7204 dentition-shaped sheet that is reported to be a very reliable measurement of occlusal forces and is unaffected by intra-oral humidity and temperature11. It is designed to quantify occlusal pressure from occlusal contact marked on a thin horseshoe-shaped sheet of film12. The sheet contains differently sized microcapsules that break and produce colour variations depending on the force of applied occlusal pressure within a range from 5 to 120?MPa to objectively assess oral function, oral force, mastication and orthodontics13�C15. After recording, the film was immediately kept in a light-resistant container and transported at room temperature for analysis. Data were entered using the Occluzer FPD705 (FujiFilm GC) on the same day to maintain reliability of the measurement16. The method by Ohyama et?al.17 was applied to the measurement requirement of the Dental Prescale System in this study. Briefly, the participant is required to practice biting in cusp to fossa occlusion, film impression with maximum force for 3?s, transport storage at room temperature and analysis within 72?h. The amount of occlusal pressure and area of occlusal contact can be estimated by measuring the density and area data through the colour image scanner of the Occluzer. Then, postural stability was determined using the automated posture analysis system (VTS-311; EGG 2000V, Patella Co., Saitama, Japan), according to the method described by the Japan Society for Equilibrium Research18. This dynamometric platform system directly reflects, measures and calculates the body��s centre of gravity movement. It records these movements in 10-s intervals per phase. The participants received prior instructions for standing upright on a posture analysis platform in the Romberg position (standing with feet aligned in the tandem heel-to-toe position, head facing straight ahead with arms down by the sides). The wall of the room facing the participants was plain white to avoid visual stimuli. The participants were instructed to gaze at a wall located 2?m away at eye level. Postural stability was measured three times at 10-s intervals each, and the mean value was entered. The upper 25% of the total number of teeth (more than 26, n?=?24) and the lower 25% of the total number of teeth (<12, n?=?22) were compared with postural stability and occlusal status. Likewise, the upper 25% of the strong occlusal force group (more than 681.0?N, n?=?23) and the lower 25% of the weak group (<244.0?N, n?=?22) were compared with postural stability. This method assesses the static stability of the participants because measurements are taken while they are standing still. Assessing the dynamic stability of the participants would have been additionally informative but because they were elderly individuals, their safety was our first priority.