A growing number of studies have reported that mini-implants do not remain in exactly the same position during treatment, although they remain stable. The aim of this review was to collect data regarding primary displ...A growing number of studies have reported that mini-implants do not remain in exactly the same position during treatment, although they remain stable. The aim of this review was to collect data regarding primary displacement immediately straight after loading and secondary displacement over time. A systematic review was performed to investigate primary and secondary displacement. The amount and type of displacement were recorded. A total of 27 studies were included. Sixteen in vitro studies or studies using finite element analysis addressed primary displacement, and nine clinical studies and two animal studies addressed secondary displacement. Significant primary displacement was detected （6.4-24.4 μm） for relevant orthodontic forces （0.5-2.5 N）. The mean secondary displacement ranged from 0 to 2.7 mm for entire mini-implants, The maximum values for each clinical study ranged from 1.0 to 4.1 mm for the head, 1.0 to 1.5 for the body and 1,0 to 1.92 mm for the tail part. The most frequent type of movement was controlled tipping or bodily movement. Primary displacement did not reach a clinically significant level. However, clinicians can expect relevant secondary displacement in the direction of force. Consequently, decentralized insertion within the inter-radicular space, away from force direction, might be favourable. More evidence is needed to provide quantitative recommendations.展开更多
AIM: To investigate the success rate of mini-implants and its characteristics and risk factors by survival analyses. METHODS: Three hundred and ninety-four miniimplants of the same type were placed by a single clinici...AIM: To investigate the success rate of mini-implants and its characteristics and risk factors by survival analyses. METHODS: Three hundred and ninety-four miniimplants of the same type were placed by a single clinician. Age, gender, treatment duration, time of failure, side and jaw of implantation and the soft tissue at placement site were recorded. Odds ratio, survival curves, and Cox proportional hazard model were applied to evaluate the factors influencing the miniimplants' success rate. RESULTS: The cumulative success rate was 88.1%.The maxilla had a significantly higher success rate than that of the mandible(91.7% vs 83.7%, respectively, P = 0.019). Placement of mini-implants in the attached gingiva(AG) showed a higher success rate than that of the mucogingival junction(MGJ) and mucous membrane(MM)(AG, 94.3%; MGJ, 85.8%; MM, 79.4%; P < 0.001). Significant association was found between the jaw and the gingival tissue type(P < 0.001). There were no significant differences between maxilla and mandible when compared within each placement site.CONCLUSION: The gingival tissue type had the most significant effect on the success rate of the mini-implant with higher success rate in the attached gingiva.展开更多
Anchorage is an important factor in orthodontics and must be properly managed for a successful treatment outcome. Orthodontists have historically used many devices to prevent unwanted tooth movement. The use of minisc...Anchorage is an important factor in orthodontics and must be properly managed for a successful treatment outcome. Orthodontists have historically used many devices to prevent unwanted tooth movement. The use of miniscrews as a source of skeletal anchorage has become routine in present-day orthodontic practice. Skeletal anchorage opens up alternative treatments, to borderline surgery patients for example, who can now be treated by taking advantage of the biomechanical properties of miniscrews. Because they are bone-borne and provide excellent control over tooth movement in the three spatial planes of movement, mini-implants can be used to serve many purposes in addition to anchorage. Therefore, a variety of successful mini-implant appliances are explained in relation to the three planes of movement: sagittal, vertical, and transverse. The aim of this review is to illustrate the clinical versatility of miniscrews in the three spatial planes of malocclusion in orthodontic and orthopedic management and to define clinical guidelines for the selection, application and biomechanics of mini-implants.展开更多
文摘A growing number of studies have reported that mini-implants do not remain in exactly the same position during treatment, although they remain stable. The aim of this review was to collect data regarding primary displacement immediately straight after loading and secondary displacement over time. A systematic review was performed to investigate primary and secondary displacement. The amount and type of displacement were recorded. A total of 27 studies were included. Sixteen in vitro studies or studies using finite element analysis addressed primary displacement, and nine clinical studies and two animal studies addressed secondary displacement. Significant primary displacement was detected （6.4-24.4 μm） for relevant orthodontic forces （0.5-2.5 N）. The mean secondary displacement ranged from 0 to 2.7 mm for entire mini-implants, The maximum values for each clinical study ranged from 1.0 to 4.1 mm for the head, 1.0 to 1.5 for the body and 1,0 to 1.92 mm for the tail part. The most frequent type of movement was controlled tipping or bodily movement. Primary displacement did not reach a clinically significant level. However, clinicians can expect relevant secondary displacement in the direction of force. Consequently, decentralized insertion within the inter-radicular space, away from force direction, might be favourable. More evidence is needed to provide quantitative recommendations.
文摘AIM: To investigate the success rate of mini-implants and its characteristics and risk factors by survival analyses. METHODS: Three hundred and ninety-four miniimplants of the same type were placed by a single clinician. Age, gender, treatment duration, time of failure, side and jaw of implantation and the soft tissue at placement site were recorded. Odds ratio, survival curves, and Cox proportional hazard model were applied to evaluate the factors influencing the miniimplants' success rate. RESULTS: The cumulative success rate was 88.1%.The maxilla had a significantly higher success rate than that of the mandible(91.7% vs 83.7%, respectively, P = 0.019). Placement of mini-implants in the attached gingiva(AG) showed a higher success rate than that of the mucogingival junction(MGJ) and mucous membrane(MM)(AG, 94.3%; MGJ, 85.8%; MM, 79.4%; P < 0.001). Significant association was found between the jaw and the gingival tissue type(P < 0.001). There were no significant differences between maxilla and mandible when compared within each placement site.CONCLUSION: The gingival tissue type had the most significant effect on the success rate of the mini-implant with higher success rate in the attached gingiva.
文摘Anchorage is an important factor in orthodontics and must be properly managed for a successful treatment outcome. Orthodontists have historically used many devices to prevent unwanted tooth movement. The use of miniscrews as a source of skeletal anchorage has become routine in present-day orthodontic practice. Skeletal anchorage opens up alternative treatments, to borderline surgery patients for example, who can now be treated by taking advantage of the biomechanical properties of miniscrews. Because they are bone-borne and provide excellent control over tooth movement in the three spatial planes of movement, mini-implants can be used to serve many purposes in addition to anchorage. Therefore, a variety of successful mini-implant appliances are explained in relation to the three planes of movement: sagittal, vertical, and transverse. The aim of this review is to illustrate the clinical versatility of miniscrews in the three spatial planes of malocclusion in orthodontic and orthopedic management and to define clinical guidelines for the selection, application and biomechanics of mini-implants.
