Swallowing patterns in human subjects with and without temporomandibular dysfunction

Recent clinical impressions have suggested that tongue-thrust swallowing may often occur in patients with internal derangement of the temporomandibular joint(s) and may represent an unconscious effort to avoid temporomandibular joint (TMJ) dysfunction by minimizing noxious stimuli from the joints. The purpose of this study, therefore, was to determine the swallowing patterns in human subjects with and without TMJ dysfunction. The swallowing patterns of 25 adult orthodontic patients already known to have TMJ dysfunction and 25 adult control subjects without such dysfunction were examined with the aid of kinesiographic and electromyographic recordings taken while the subjects were sipping water. Analysis of the data revealed that 19 patients with TMJ dysfunction used a tongue-thrust open-jaw swallowing pattern, while only nine control subjects used such a swallowing pattern. Furthermore, six of the patients with TMJ dysfunction had an anterior open bite, while none of the control subjects had an anterior open bite. The results suggest that patients with aberrant swallowing patterns should be examined for temporomandibular joint dysfunction.