IADR Abstract Archives
Removal torque of CP titanium screw implants with different surface treatments
Objectives: rough titanium surfaces are known to produce a quicker osseointegration of dental implants, compared with smooth or machined surfaces. The goal of this work was to further investigate this topic, not completely cleared about the best roughening method.
Methods: commercially pure (CP) titanium screw implants were inserted in the tibia of 48 New Zealand white rabbits. The animals were operated in general anaesthesia, and fixtures were placed into the front tibia. The implants, built on purpose, were 5 mm in length and 3.4 mm in diameter, of the same brand (AT Implant System, Padua, Italy), and were divided into four groups of 12 specimens, with different surface treatments: 1) Al2 O3 sand-blasted and HF etched; 2)machined ; 3) Al2 O3 sand-blasted; 4) HF etched. Treatment 1) is commonly carried out on these implants utilised in the clinical practice. After 16 weeks , the rabbits were sacrificed, and the implant heads exposed. Removal torque was then measured, by means of a Tohnichi dynamometer.
Results: removal torque values were as follows:
Removal torque in N/cm after 16 weeks:
|
1)etched + sand-blasted |
25 |
24 |
23 |
25 |
13 |
10 |
18 |
11 |
32 |
10 |
9 |
11 |
mean 17.5 ± 7.8 |
|
2)machined |
15 |
17 |
17 |
18 |
13 |
28 |
16 |
18 |
16 |
16 |
15 |
18 |
17.2 ± 3.6 |
|
3)sand-blasted |
8 |
8 |
8 |
8 |
8 |
7 |
8 |
10 |
12 |
7 |
9 |
9 |
8.5 ± 1.3 |
|
4)etched |
17 |
17 |
18 |
20 |
18 |
12 |
15 |
16 |
20 |
18 |
8 |
19 |
16.5 ± 3.4 |
Torque values are significantly lower for sand-blasted implants, compared to all the other treatments (P<0.001), while no statistically significant difference exists among the three remaining groups, even if the torque for etched+sand-blasted surfaces appears as the highest one.
Conclusions: these results confirm the effectiveness of the usual roughening treatment 1) to guarantee a valid bone anchorage of these dental implants.