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An Improved Mechanical Testing Method to Assess Bone-implant Anchorage
Published on: February 10, 2014
The effect of miniscrew length and bone density on anchorage resistance: An in vitro study
I Gusti Aju Wahju Ardani1, Rachman Indharmawan2, Thalca Hamid2
1Orthodontic Department, Faculty of Dental Medicine, Campus A Universitas Airlangga Jl, Prof. Dr. Moestopo No. 47, 60132 Surabaya, East Java, Indonesia..
Introduction:
With conventional anchorage, it is usually hard to accomplish a satisfactory result with an absolute anchorage, and this limitation could be resolved by the usage of mini-screw. The successful rate of miniscrew usage depends on its stability, which was determined by its length, bone density, cortical bone thickness, the insertion technique, the insertion angle, and the applied loads.
Objective:
To observe the effect of miniscrew length and bone density on anchorage resistance.
Material And Methods:
Thirty pieces of miniscrew with 1.6mm in diameter were divided into three groups based on its length (n=10): 10mm (L), 8mm (M), and 6mm (S). Each group was further divided into 2 sub-groups: to be planted in optimal density bovine ribs (L1, M1, S1) and to be planted in low-density bovine ribs (L2, M2, S2). The density of bovine ribs was measured by CBCT. After the insertion of miniscrews based on respective groups, tensile test was done by means of Autograf Univerval Testing Machine to measure its stability. The data recorded was analysed using the Least Significant Difference (LSD) Fisher's test.
Results:
The results of this study showed that L1 provided the greatest stability than other groups. On the other hand, the least stability was found in S2.
Conclusion:
The length of miniscrew and the density of bone affect the stability of miniscrew. In bone with optimum density, 10mm and 8mm miniscrew equipped good anchorage resistance while in bone with low-density only 10mm miniscrew provided favourable anchorage resistance.
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