Mechanical Evaluation of the Stability of One or Two Miniscrews under Loading on Synthetic Bone

Abstract

The aim of the present study was to evaluate the primary stability of a two-miniscrew system inserted into a synthetic bone and to compare the system with the traditional one. Forty-five bi-layered polyurethane blocks were used to simulate maxillary cancellous and cortical bone densities. Samples were randomly assigned to three groups—one-miniscrew system (Group A, N = 23), two-miniscrew system (Group B, N = 22) and archwire-only (Group C, N = 10). A total of 67 new miniscrews were subdivided into Group A (23 singles) and Group B (22 couples). 30 mm of 19″ × 25″ archwires were tied to the miniscrew. The load was applied perpendicularly to the archwire. Maximum Load Value (MLV), Yield Load (YL) and Loosening Load (LL) were recorded for each group. The YL of Group B and C had a mean value respectively of 4.189 ± 0.390 N and 3.652 ± 0.064 N. The MLV of Group A, B and C had a mean value respectively of 1.871 ± 0.318N, of 4.843 ± 0.515 N and 4.150 ± 0.086 N. The LL of Group A and B had a mean value respectively of 1.871 ± 0.318 N and of 2.294 ± 0.333 N. A two- temporary anchorage device (TAD) system is on average stiffer than a one-TAD system under orthodontic loading.

Canine Impaction: Digital Orthodontic Planning in Conjunction with TADs (Temporary Anchorage Devices) and Aligners

“…According to the study by Migliorati et al, by using the direct anchorage, the canine showed a 1 mm/month movement speed rate for the root apex and slightly faster movement in terms of cusp movement when compared to the use of the indirect [19,20]. The single-TAD approach is impressive and simple to handle, but it should be noted that some authors prefer the use of two-TAD technique to reduce any stability problems due to traction activation [21][22][23].…”

Intercepting of Class III Malocclusion with a Novel Mechanism Built on the Orthopaedic Appliance: A Case Report

“…The possibility of using the skeletal anchorage [ 10 ] to manage the agenesis is included in the consent form to avoid adverse dental effects and for the lack of dental anchorage in the anterior zone.…”

A Biomechanical Analysis of the Influence of the Morfology of the Bone Blocks Grafts on the Transfer of Tension or Load to the Soft Tissue by Means of the Finite Elements Method

“…Taking into account the scientific literature, it was assumed that the microscrews were totally osseointegrated into the cortical blocks of the graft and the remaining bone of the jaw, considering the osseointegration to be the direct, structural and functional connection between the living bone and the surface of a microscrew [35][36][37]. Those areas not affecting the surgery are defined as fixed nodes and zero displacement was assumed for them [25,38].…”