| Buccal | Lingual | Mesial | Distal | Average |
PMMA1 N = 33 | 20.2 ± 13.2 | 26.8 ± 18.6 | 41.7 ± 15.6 | 40.2 ± 18.7 | 32.3 ± 12.3 |
Y-ZIR N = 33 | 2.8 ± 4.6** | 5.8 ± 8.9** | 10.1 ± 10.0** | 10.8 ± 9.6** | 7.5 ± 6.4** |