Chi-square test | Zirconia crowns | Strip crowns | p-value | |
---|---|---|---|---|
Plaque index | ||||
At 3 months | No plaque | 20 (33.3%) | 4 (6.7%) | < 0.001a |
A film of plaque adhering to the free gingival margin, cannot be seen with the naked eye | 36 (60.0%) | 44 (73.3%) | ||
Moderate accumulation of deposits in the gingival pocket, on gingival margin and/or adjacent tooth surface, can be seen by the naked eye | 4 (6.7%) | 12 (20.0%) | ||
At 6 months | No plaque | 47 (79.7%) | 24 (40.0%) | < 0.001a |
A film of plaque adhering to free gingival margin, cannot be seen by naked eye | 12 (20.3%) | 36 (60.0%) | ||
At 12 months | No plaque | 58 (100.0%) | 48 (80.0%) | 0.001a |
Film of plaque adhering to the free gingival margin, cannot be seen with naked eye | 0 (0.0%) | 12 (20.0%) |
Friedman test | Mean rank | |||
---|---|---|---|---|
Total cases | Zirconia crown | Strip crown | ||
Baseline | 1.85 | 2.07 | 1.63 | |
At 3 months | 3.56 | 3.45 | 3.67 | |
At 6 months | 2.58 | 2.41 | 2.73 | |
At 12 moths | 2.02 | 2.07 | 1.97 | |
p-value | < 0.001b | < 0.001b | < 0.001b |