The replica impressions were taken from each patient;
a primary impression was taken of the maxillary
arch using alginate
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, into which stone
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was poured.
The resulting cast was used to construct a special
perforated tray without palatal coverage to ensure
consistent positioning of the replica impression into the
subject s mouth by using heavy body impression materials,
and then then by reapplying this trial impression
into the subject s mouth ?lled with light body
impression materials
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. If the catalyst and paste were
mixed too vigorously, air bubbles might have accumulated
in the replica. To correct this problem a very
thin layer was applied initially. This was followed by a