Forty autopolymerizing resin record bases were made; 10 bases were ada
pted by finger pressure on tray resin material dough, 10 bases by spri
nkling orthodontic resin, and 10 of repair material by either of the t
wo previous techniques. Stone casts and acrylic resin bases were secti
oned at canine, premolar, and molar coronal planes. Width of the gap b
etween base and cast and the thickness of the base were measured at th
e buccal sulcus, ridge crest, lateral palatal slope, and palatal midpo
int. Measurements were made through the eyepiece of a microhardness te
ster. Statistical analysis of 760 pairs of measurements revealed that
(1) sprinkled bases fit better than finger-adapted dough bases; (2) sp
ecifically formulated materials fit better than repair material with e
ither technique; (3) gap widths differed at different areas of the sam
e base; and (4) gap width was not related to base thickness at any poi
nt.