Mechanical Characteristics of Various Orthodontic Mini-screws in Relation to Artificial Cortical Bone Thickness

Abstract

Since different screw designs showed different insertion torques with increases in cortical bone thickness, the suitable screw design should be selected according to the cortical thickness at the implant site.

Is miniscrew primary stability influenced by bone density?

“…Cortical thickness has been related to primary stability of miniscrews and implants. 5,12,28,29,30 However, there is a lack of studies isolating these two factors: bone density and cortical thickness. The second hypothesis is that the difference in bone quality verified statistically may not be clinically relevant.…”

“…1,2 It is achieved by mechanical contact between the miniscrew surface and bone 3 and depends on the characteristics of devices 4,5 , insertion technique 4 and bone quality and quantity of the receptor site. 4,[6][7][8] The primary stability plays an important role in the successful secondary stability of miniscrews, since lack of immediate stability can lead to progressive mobility of the device and its subsequent loss.…”

Temporary Anchorage Device Stability: Monocortical Versus Bicortical Anchorage Technique

“…[12][13] Primary stability of the orthodontic miniscrew occurs when mechanical stability is achieved in the bone immediately after the miniscrew is inserted into the bone. [14][15][16][17][18] The primary stability of temporary skeletal anchorage can be influenced by many factors including geometry of miniscrew, bone characteristics, angulation placement of miniscrew and pullout force which is the major factor for clinical success with miniscrews. [19][20] These factors may directly or indirectly affect the results.…”

Estudo in vitro da perfuração radicular por diferentes diâmetros de mini-implantes

“…Este material tem sido usado em ensaios biomecânicos com mini-implantes (BRINLEY et al, 2009;HWANG, 2008;PETREY et al, 2010;SONG; et al, 2010). Todo o processo de substituição do silicone pela espuma de poliuretano foi realizado pela empresa Nacional Ossos (Jaú, SP).…”

“…Assim, optou-se pela utilização de osso artificial para servir de suporte aos dentes e também como meio de inserção de miniimplantes para comparação com os dentes humanos. Trata-se de um material à base de espuma sólida rígida de poliuretano, disponível em diversas densidades e empregado em testes experimentais com mini-implantes (BRINLEY et al, 2009;HWANG, 2008;PETREY et al, 2010;SONG;. O uso de osso artificial em ensaios mecânicos pode apresentar resultados diferentes do que os obtidos em humanos, porém ter uma uniformidade da densidade e da espessura da cortical óssea pode ser uma vantagem (CIARELLI et al, 1991).…”