Table 4.
Non parametric MANCOVA on precision measurements (tooth movement) performed with different settings, cleaning status, and time points.
| Operator factor | d.f. | F | P |
|---|---|---|---|
| Covariate (patient) | 1 | 14.609 | 0.001* |
| Superimposition | 2 | 13.281 | 0.016* |
| Tooth | 2 | 1.105 | 0.328 |
| Setting | 1 | 0.032 | 0.993a |
| Cleaning | 1 | 0.045 | 0.993a |
| Time | 1 | 0.007 | 1.000a |
| Superimposition x Tooth | 4 | 0.145 | 1.000 |
| Superimposition x Setting | 2 | 0.366 | 0.823 |
| Superimposition x Cleaning | 2 | 1.725 | 0.208 |
| Superimposition x Time | 2 | 0.438 | 0.814 |
| Tooth x Setting | 2 | 1.968 | 0.095 |
| Tooth x Cleaning | 2 | 1.462 | 0.169 |
| Tooth x Time | 2 | 1.579 | 0.152 |
| Setting x Cleaning | 1 | 0.001 | 0.892 |
| Setting x Time | 1 | 0.006 | 0.883 |
| Cleaning x Time | 1 | 0.024 | 0.910 |
| Superimposition x Tooth x Setting | 4 | 0.211 | 0.993 |
| Superimposition x Tooth x Cleaning | 4 | 0.031 | 1.000 |
| Superimposition x Tooth x Time | 4 | 0.023 | 1.000 |
| Superimposition x Setting x Cleaning | 2 | 0.361 | 0.872 |
| Superimposition x Setting x Time | 2 | 0.457 | 0.835 |
| Superimposition x Cleaning x Time | 2 | 1.389 | 0.322 |
| Tooth x Setting x Cleaning | 2 | 4.788 | 0.003* |
| Tooth x Setting x Time | 2 | 4.833 | 0.001* |
| Tooth x Cleaning x Time | 2 | 4.279 | 0.004* |
| Setting x Cleaning x Time | 1 | 0.009 | 0.951 |
| Superimposition x Tooth x Setting x Cleaning | 4 | 0.069 | 1.000 |
| Superimposition x Tooth x Setting x Time | 4 | 0.040 | 1.000 |
| Superimposition x Tooth x Cleaning x Time | 4 | 0.076 | 1.000 |
| Superimposition x Setting x Cleaning x Time | 2 | 0.806 | 0.543 |
| Tooth x Setting x Cleaning x Time | 2 | 13.700 | 0.001* |
| Superimposition x Tooth x Setting x Cleaning x Time | 4 | 0.110 | 1.000 |
| Residual | 647 | ||
| Total | 719 | ||
| Comparison b | t | p-value | |
| A vs. B | 4.618 | 0.002*a | |
| A vs. C | 2.922 | 0.022*a | |
| B vs. C | 3.358 | 0.019*a | |
| Comparison c | t | p-value | |
| Setting 1, Incisor: Cleaned vs. Original | 0.664 | 0.650 | |
| Setting 1, Molar R: Cleaned vs. Original | 2.136 | 0.009** | |
| Setting 1, Molar L: Cleaned vs. Original | 1.319 | 0.164 | |
| Setting 2, Incisor: Cleaned vs. Original | 1.434 | 0.127 | |
| Setting 2, Molar R: Cleaned vs. Original | 0.777 | 0.556 | |
| Setting 2, Molar L: Cleaned vs. Original | 2.201 | 0.012 | |
| Comparison d | t | p-value | |
| Time 1, Incisor: Cleaned vs. Original | 0.586 | 0.733 | |
| Time 1, Molar R: Cleaned vs. Original | 1.829 | 0.032 | |
| Time 1, Molar L: Cleaned vs. Original | 1.3576 | 0.159 | |
| Time 2, Incisor: Cleaned vs. Original | 1.432 | 0.125 | |
| Time 2, Molar R: Cleaned vs. Original | 0.587 | 0.733 | |
| Time 2, Molar L: Cleaned vs. Original | 2.229 | 0.008** |
Five crossed factors and their possible interactions were analyzed in each case having patient as a covariate: superimposition technique (fixed factor; 3 techniques), tooth (random factor; 3 teeth), setting (fixed factor; 2 settings), cleaning (fixed factor; 2 status), and time (fixed factor; 2 measurement time points). All vectors of positional change of each tooth were considered as dependent variables (6 vectors: x-lateral movement, y-anteroposterior movement, z-vertical movement, x-torque, y-tip, z-rotation).
999 permutations.
*p < 0.05.
aMonte Carlo asymptotic p-value.
bTests among levels of the factor Superimposition.
cTests among levels of the factor Cleaning within levels of factors Setting and Tooth.
dTests among levels of the factor Cleaning within levels of factors Time and Tooth.
A, B, C correspond to the five superimposition techniques and reference areas tested in the study.