Microimplantes, una nueva opción en el tratamiento de Ortodoncia

Los microimplantes son pequeños pines de titanio o de aleación de titanio de 1,2 mm de diámetro y 6 mm de longitud. Están diseñados con una superficie suave para que no se oseointegren. Son utilizados en Ortodoncia como anclaje temporal. Han sido usados como anclaje esqueletal, también para distalizar y protraer molares, intruir molares e incisivos, para el cierre de espacios edéntulos extensos que con los métodos convencionales en ortodoncia habría sido imposible. Los microimplantes son removidos con relativa facilidad una vez efectuado el procedimiento. Como toda técnica nueva, es importante que los clínicos sepan elegir bien en qué casos van a utilizar los micro implantes y los sitios de su colocación.

The miniimplants are small devices of 1,2 mm of wide and 6 mm of length. Manufactured with a smooth machined surface that is not designed to osseointegrate. In orthodontics they are used as temporary anchorage for molar distalization, protraction and intrusion of molars and incisors. Also for closing wide edentulous spaces once considered impossible with conventional orthodontics.. The miniimplants are easily removed. As with any new technique clinicians should be aware in which cases use this devices and the sites of placing them.

Three-dimensional finite element analysis of a newly designed onplant miniplate anchorage system / 华中科技大学学报（医学）（英德文版）

The purpose of this research was to evaluate the structural stress and deformation of a newly designed onplant miniplate anchorage system compared to a standard anchorage system. A bone block integrated with a novel miniplate and fixation screw system was simulated in a three-dimensional model and subjected to force at different directions. The stress distribution and deformation of the miniplate system and cortical bone were evaluated using the three-dimensional finite element method. The results showed that the stress on the plate system and bone was linearly proportional to the force magnitude and was higher when the force was in a vertical direction (Y-axis). Stress and deformation values of the two screws (screw 1 and 2) were asymmetric when the force was added along Y-axis and was greater in screw 1. The highest deformation value of the screws was 7.5148 μm, much smaller than the limit value. The load was decreased for each single miniscrew, and the ability of the new anchorage system to bear the load was also enhanced to some degree. It was suggested that the newly designed onplant miniplate anchorage system is effective, easily implanted and minimally invasive.

The efficiency of SAS used retraction of the anterior teeth on orthodontic treatment

The retraction of anterior teeth could be performed more easier by inducing of skeletal anchorage system rather than by conventional method on orthodontic treatment. But, we wonder how effective the system draws well without anchorage loss and draws anterior teeth aside posteriorly, and if the system can reduce the time, in comparison with the anchorage of posterior teeth. For that reason we have studied on the subject of patients, who were required the maximum anchorage on orthodontic treatment and the cases without crowding. The subjects of the experimental group are 35 areas of 20 people who were inserted miniscrews after Mx or Mn 1st premolar extracted. Also, the subjects of the control group are 81 areas of 45 people who were not inserted miniscrews. Compared the anchorage loss of experimental group with control one, we could get the result that the anchorage loss of experimental group is 1.034+/-0.891mm and control group is 2.790+/-1.882mm(P<0.01). Compared the space closing time of experimental group with control one, we could get the result that the space closing time of experimental group is 369.40+/-110.81days and control group is 406.56+/-231.63days. But the result of comparing space closing time has no significance in statistics. We recognized that the experimental group is more faster than the control group in the canine retraction velocity from the result ; the speed of a experimental group has as much as 0.60+/-0.23mm/30days while the speed of a control group has 0.44+/-0.35mm/30days(P<0.05). So, we could convince that orthodontic miniscrew is used effectively in the cases required the maximum anchorage.

Intrusion Of The Severe Extruded Maxillary Post.Teeth Using Post.Segmental Osteotomy And Orthodontic Treatment With Skeletal Anchorage System: Cases Report

Study Of Maxillary Cortical Bone Thickness For Skeletal Anchorage System In Korean

Recently, Skeletal Anchorage System (SAS) has been focused clinically with the view point that it could provide the absolute intraoral anchorage. First, it began to be used for the patient of orthognathic surgery who had difficulty in taking intermaxillary fixation due to multiple loss of teeth. And then, its uses have been extended to many cases, the control of bone segments after orthognathic surgery, stable anchorage in orthodontic treatment, and anchorage for temporary prosthesis and so on. SAS has been developed as dental implants technique has been developed and also called in several names; mini-screw anchorage, micro-screw anchorage, mini-implant anchorage, micro-implant anchorage (MIA), and orthosystem implant etc. Now many clinicians use SAS, but the anatomical knowledges for the installed depth of intraosseous screws are totally dependent on general experiences. So we try to study for the cortical thickness of maxilla and mandible in Korean adults without any pathologic conditions with the use of Computed Tomography at the representative sites for the screw installation.