Bone quality affects stability of orthodontic miniscrews

Abstract

The objective of this study was to evaluate the effect of bone–miniscrew contact percentage (BMC%) and bone quality and quantity on orthodontic miniscrew stability and the maximum insertion torque value (ITV). Orthodontic miniscrews of five different dimensions and several bovine iliac bone specimens were used in the evaluation. Miniscrews of each dimension group were inserted into 20 positions in bovine iliac bone specimens. The experiment was divided into three parts: (1) Bone quality and quantity were evaluated using cone-beam computed tomography (CBCT) and microcomputed tomography. (2) The 3D BMC% was calculated. (3) The ITVs during miniscrew insertion were recorded to evaluate the stability of the orthodontic miniscrews. The results indicated that longer and thicker miniscrews enabled higher ITVs. CBCT was used to accurately measure cortical bone thickness (r = 0.939, P < 0.05) and to predict the bone volume fraction of cancellous bone (r = 0.752, P < 0.05). BMC% was significantly influenced by miniscrew length. The contribution of cortical bone thickness to the ITV is greater than that of cancellous bone structure, and the contribution of cortical bone thickness to BMC% is greater than that of cancellous bone structure. Finally, the higher is BMC%, the greater is the ITV. This study concludes that use of CBCT may predict the mechanical stability of orthodontic miniscrews.

Design of Induction Heatable Carbon‐Based Foams for Catalysis

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Correction of Midline Deviation and Unilateral Crossbite Treated with Fixed Appliance

“…Systematic reviews and meta-analysis demonstrated that the use of mini screws is strongly recommended in cases of maximum anchorage than other methods or combinations of treatments and it is associated with a shorter duration treatment time [ 17 – 19 ]. Whereas other reviews and meta-analysis showed that miniscrews have an acceptably low failure rate linked to insertion sites [ 20 ], to minidesign of screws [ 21 ], and to cortical bone thickness [ 22 ].…”

The success rate of mini‐screws for incisors intrusion and patient age, gender, and insertion angle in the maxilla using CBCT and implant‐guided surgery. A split‐mouth, randomized control trail

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“…The poorer bone quality and a higher bone turnover rate in adolescents complicate the achievement of optimal mechanical mini-screw stability in growing patients. 42,43 Further explanation may be due to the distinction in bone maturation adults and adolescents. 44 An interesting finding was that mini-screws in the male group were more stable than in the female group over the follow-up period except for the first month, where both were equal in screw stability.…”