Effect of preparation methods of recipient site on primary implant stability in various bone qualities

Cui, De Zhe; Vang, Mong Sook; Oh, Hee Kyun

Abstract

STATEMENT OF PROBLEM: After placing the implant on the jaw, firm osseointegration between the implant interface and the bone should be achieved so that it can perform the same function as the normal teeth. That is, stability of the implant is required in order to form firm osseointegration. PURPOSE: This study was performed to evaluate the effect of implant preparation methods on primary implant stability in various bone qualities. MATERIAL AND METHODS: The recipient sites were prepared by various methods on 4 types of wooden plates (Osstem Co., Korea) which have similar mechanical properties with 4 types of human bone quality. The groups were divided according to implant preparation methods: In the control group the recipient sites were prepared from 1.8 mm guide drill, 2.0 mm initial drill, 2.7 mm pilot drill, 2.7 mm twist drill, 3.0 mm twist drill, 3.3 mm pilot drill, 3.3 mm twist drill, countersink drill, and tapping drill sequentially and 6 RBM surfaced GSII Osstem implants (Osstem Co., Korea) were installed in each type of wooden plates; In group 1, the recipient sites were prepared from 1.8 mm guide drill to 3.0 twist drill sequentially without countersink drill nor tapping drill and implants were placed; In group 2, the recipient sites were prepared from 1.8 mm guide drill to 3.0 mm twist drill, and countersink drill sequentially without tapping drill and implants were placed; In group 3, the recipient sites were prepared from 1.8 mm guide drill to 3.0 mm twist drill, countersink drill, and tapping drill sequentially and implants were placed; In group 4, the recipient sites were prepared from 1.8 mm guide drill to 3.3 mm twist drill sequentially without countersink drill nor tapping drill and implants were placed; In group 5, the recipient sites were prepared from 1.8 mm guide drill to 3.3 mm twist drill and countersink drill sequentially without tapping drill and implants were placed; In group 6, the recipient sites were prepared with 2.0 mm twist drill and 3.0 mm osteotome and implants were placed. The insertion torque was measured by INTRA surg(R)300 (KaVo., Germany). After installation of implants, the primary implant stability was measured by using Osstell(TM), Osstell(TM) mentor, and Periotest(R), and insertion torque test. The statistical analysis of the results was analyzed using SPSS ver. 12.0. Student t-tests and one-way analysis of variance (ANOVA) were used.
RESULTS
The results obtained were as follows; 1. In type I and II bone quality plates, although the mean value of primary implant stability was somewhat different according to test methods, the primary implant stability of group 1 was significantly higher than those of other groups (p<0.05). 2. In type III bone quality plate, the primary implant stability of group 1 was significantly higher than those of other groups in Osstell(TM) test, the primary stability of group 1 and group 6 were significantly higher than those of other groups in Osstell(TM) mentor and Periotest(R), and the stability of group 6 was significantly higher than those of other groups in insertion torque test (p<0.05). 3. In type IV bone quality plate, the primary implant stability of group 6 was significantly higher than those of other groups (p<0.05). 4. As the quality of bone was softer, the primary implant stability tended to be lower in values. This tendency was not significantly different in Osstell(TM) and Osstell(TM) mentor tests, but it was significantly different in insertion torque test (p<0.05). 5. In type IV bone quality plate, the mean values of primary implant stability which were calculated by Osstell(TM) was 14.8+/-8.6 higher than the values calculated by Osstell(TM) mentor.
CONCLUSION
These results suggest that the recipient implant preparation by using minimal drilling and osteotome may be useful in obtaining the primary implant stability and the insertion torque test seems be the most simple and predictable method.