Vol 21 No. 1

J Bagh College Dentistry Vol. 21(1), 2009 The effect of using different …..
Table 3: Number and percentage % of dentists with different specialties and their choices of
impression techniques.
Impression techniques
General dentist (30) Specialist (39) Prosthodontist(21)
No. of dentist % No. of dentist % No. of dentist %
Stock tray with alginate 5 16.67 7 17.95 3 14.29
Special tray with alginate 15 50 20 51.28 5 23.81
Double tray 5 16.67 1 2.56 8 38.1
Special tray with rubber base 5 16.67 11 28.21 5 23.81
Table 4: Mean, standard deviation, standard errors and coefficient of variation of displacement
for the different impression techniques and materials at each measured points.
Impression techniques and materials
Statistic
Special tray with alginate
impression material
Double tray
impression
Special tray with polyether
impression material
Point A Point B Point C
Point Point Point
A B C
Point A Point B Point C
Mean 8.311 9.077 8.491 8.063 8.766 8.025 8.132 8.674 7.885
SD 1.786 1.706 1.627 1.814 1.653 1.581 2.010 2.042 2.124
SE 0.364 0.348 0.332 0.370 0.337 0.322 0.410 0.416 0.433
CV% 21.49 18.795 19.161 22.498 18.857 19.7 24.7 23.5 26.94
Table 5: t-test of displacement for two impression materials [special tray with alginate and
special tray with polyether]
Special tray with alginate and
Point Statistical t-test P-value Sig.
special tray with polyether
A
MD 0.179
SD 0.643
1.361 0.187 NS
B
MD 0.403
SD 0.142
2.832 0.009 S
C
MD 0.605
SD 0.189
3.336 0.003 S
*P>0.05 Non significant
**P0.05 Non significant
**P0.05 NS
B 2.604 0.084 P>0.05 NS
C 3.388 0.042 P0.05 Non significant
**P