Intraoral Pressures in a Young Adult Group

¹ Departments of Orthodontics and Prosthodontics, University of Washington School of Dentistry, Seattle, Washington

In order to better establish the range of intraoral pressures found in a "normal" sample, tongue and lip forces against the teeth during swallowing were evaluated in 19 young adult males. Strain gauge pressure transducers were placed so as to allow simultaneous recording: (1) labial to the maxillary central incisors, (2) lingual to the maxillary central incisors when the teeth were in occlusion, and (3) lingual to the maxillary first molar. A mercury strain gauge around the neck was used as an indicator of swallowing.

Tongue pressure during swallowing was invariably seen in incisor and molar regions, and tended to occur simultaneously in the two areas. For each individual, a relatively consistent pattern of pressure applications during a swallow was noted. Large differences between individuals, both in pressure pattern and in maximum pressures exerted in each region, were observed.

It appears that a wide range in maximum lip and tongue forces occurs in subjects with similar dentitions. Evaluation of abnormal muscle function with pressure transducers may present problems of interpretation.