More than 2,000 patients were included in the more than 40 published articles, and as mentioned earlier, the result shows a mean marginal bone level change of -0.3 mm after the first year of loading and it remains at the same level after five years. But when summarizing our data and making the comparison between the current standard norm and the Astra Tech Implant System™ level, we decided to raise the bar even higher. In addition to being of high scientific value, we added five important criteria that the Astra Tech Implant System articles had to fulfill:
- radiological studies
- prospective studies
- implants with MicroThread™
- complete study cohorts
- use of standard implant surgery protocol
(studies on augmentation techniques and implants
placed in extraction sockets were not included)
After meeting the set criteria the twelve articles below remained. They represent approximately 400 patients with follow-up times of 1, 2, 3 and 5 years and confirm the exceptional result.
When the Astra Tech Implant System data was presented to Tomas Albrektsson, Professor of Biomaterial Research at the Sahlgrenska Academy, University of Gothenburg, Sweden, one of the authors of articles from 1986 and 1993, he said in a press release*:
“The limited marginal bone resorption being documented on Astra Tech implants indicates that it is time to reconsider our old ‘standard’ from 1986. The new standard should perhaps only allow 50% or less of the bone resorption currently accepted as a successful result.”
It is certainly time to set a new standard.
* Unique data presented on Astra Tech implants: challenges current standard for success!, June 4, 2008.
|
| Author(s) |
Title |
Publication |
No. of patients |
Year
|
Bone level change (mm) |
| Cooper L., et al. |
A multicenter 12-month evaluation of single-tooth implants restored 3 weeks after 1-stage surgery. |
Int J Oral Maxillofac Implants 2001;16(2):182-92. |
52 |
1 |
-0.40 |
| Norton M.R., et al. |
A short-term clinical evaluation of immediately restored maxillary TiOblast single-tooth implants. |
Int J Oral Maxillofac Implants 2004;19(2):274-81. |
25 |
1 |
-0.40 |
| Nordin T., et al. |
The use of a conical fixture design for fixed partial prostheses. A preliminary report. |
Clin Oral Impl Res 1998;9(5):343-7. |
10 |
1 |
-0.05 |
| Donati M., et al. |
Immediate functional loading of implants in single tooth replacement: a prospective clinical multicenter study. |
Clin Oral Implants Res 2008;19(8):740-8. |
151 |
1 |
-0.31 |
| Karlsson U., et al. |
Single-tooth replacement by osseointegrated Astra Tech dental implants: a 2-year report. |
Int J Prosthodont 1997;10(4):318-24. |
47 |
2 |
-0.31 |
| Palmer R.M., et al. |
A prospective study of Astra single tooth implants. |
Clin Oral Impl Res 1997;8(3):173-9. |
15 |
2 |
-0.00 |
| Palmer R.M., et al. |
A prospective 3-year study of fixed bridges linking Astra Tech ST implants to natural teeth. |
Clin Oral Implants Res 2005;16(3):302-7. |
19 |
3 |
-0.13 |
| Lee D.W., et al. |
Effect of microthread on the maintenance of marginal bone level: a 3-year prospective study. |
Clin Oral Impl Res 2007;18(4):465-70. |
17 |
3 |
-0.24 |
| Cooper L., et al. |
Three-year evaluation of single-tooth implants restored 3 weeks after 1-stage surgery. |
Int J Oral Maxillofac Implants 2007;22(5):791-800. |
54 |
3 |
-0.42 |
| Palmer R.M., et al. |
A 5-year prospective study of Astra single tooth implants. |
Clin Oral Implants Res 2000;11(2):179-82. |
15 |
5 |
+0.12 |
| Wennström J.L., et al. |
Implant-supported single-tooth restorations: a 5-year prospective study. |
J Clin Periodontol 2005;32(6):567-74. |
40 |
5 |
-0.11 |
| Gotfredsen K. |
A 5-year prospective study of single-tooth replacements supported by the Astra Tech implant: a pilot study. |
Clin Implant Dent Relat Res 2004;6(1):1-8. |
20 |
5 |
-0.34 |
|