Diurnal variation in palatal tissue thickness

Abstract

A small micrometer, attached to an acrylic resin hood or bridge which straddled the upper arch and which fitted the occlusal surfaces of the molar and premolar teeth exactly, was used to measure diurnal changes in palatal tissue topography. The palatal tissues of three men were measured seven times on each of three different days, in a total of fourteen palatal positions level with the first molar teeth. The results indicate that the palatal tissues were thickest when the subjects were lying in bed after a full night's sleep. Upon arising, there was an immediate and rapid shrinkage of the tissues which tapered off in the afternoon (Fig. 5). There appeared to be a slight increase in tissue thickness again throughout the evening before retiring, and a further increase in thickness when the subjects lay down for the night, but the tissues were thinner at this time than they had been in the morning. In another study, the palatal tissues of ten men, 25 to 35 years of age, were measured at two palatal locations each morning and afternoon for ten days. The results indicate that, in general, the palatal tissues shrink from morning to afternoon. The mean shrinkage in the midline was 0.0023 inches (0.0584 mm.) and on the right palatal slope 0.0045 inches (0.1143 mm.). However, the shrinkage found in the various subjects was significantly different, so the mean is not applicable to any individual.