Experimentelle Untersuchungen zum Bruchdrehmoment kieferorthopädischer Minischrauben

TY - JOUR

T1 - Experimentelle Untersuchungen zum Bruchdrehmoment kieferorthopädischer Minischrauben

AU - Reimann, Susanne

AU - Ayubi, Mustafa

AU - McDonald, Fraser

AU - Bourauel, Christoph

PY - 2016/4/20

Y1 - 2016/4/20

N2 - Objectives: In contrast to dental implants that remain in the bone, orthodontic anchorage screws serve as temporary anchorage for orthodontic tooth movement and are removed after completion of treatment. The aim of the present study was to evaluate the stability of various commercially available orthodontic anchorage screws against torsion. Materials and methods: The torsional deflection of ten different orthodontic anchorage screws from different manufacturers [Ortho Easy Pin (Forestadent), Benefit, quattro (both PSM Medical Solutions), Vector TAS (Ormco), AbsoAnchor® (DENTOS Inc.), OrthoLox, Dual-Top JA (both Promedia Medizintechnik), TAD (3M Unitek), INFINITAS (ODS) and tomas® (Dentaurum)] was tested in vitro in relation to the rotation angle using a self-developed set-up. The screws were positioned in a resin model with bone-like material properties. Shear tests were performed using the manufacturers’ own screwdrivers. Ten screws each were turned manually until a sudden drop in the measured torque occurred. At this point, the screw head was twisted off. Fracture torque and the torque at which the screws deformed plastically were evaluated. Mean values and standard deviations were calculated. Results: According to the German industrial standard, the torque of orthodontic anchorage screws should reach at least 20 Ncm. The majority of the screws reached this nominal torque; however, a few screws fractured before reaching this value. Five screw types displayed plastic deformation below the threshold, at approximately 16 Ncm. Conclusions: The results suggest that orthodontic anchorage screws generally meet the requirements of the standard and ensure safe clinical use. However, according to the present data, it may be assumed that a portion of the screws will be plastically deformed upon removal.

AB - Objectives: In contrast to dental implants that remain in the bone, orthodontic anchorage screws serve as temporary anchorage for orthodontic tooth movement and are removed after completion of treatment. The aim of the present study was to evaluate the stability of various commercially available orthodontic anchorage screws against torsion. Materials and methods: The torsional deflection of ten different orthodontic anchorage screws from different manufacturers [Ortho Easy Pin (Forestadent), Benefit, quattro (both PSM Medical Solutions), Vector TAS (Ormco), AbsoAnchor® (DENTOS Inc.), OrthoLox, Dual-Top JA (both Promedia Medizintechnik), TAD (3M Unitek), INFINITAS (ODS) and tomas® (Dentaurum)] was tested in vitro in relation to the rotation angle using a self-developed set-up. The screws were positioned in a resin model with bone-like material properties. Shear tests were performed using the manufacturers’ own screwdrivers. Ten screws each were turned manually until a sudden drop in the measured torque occurred. At this point, the screw head was twisted off. Fracture torque and the torque at which the screws deformed plastically were evaluated. Mean values and standard deviations were calculated. Results: According to the German industrial standard, the torque of orthodontic anchorage screws should reach at least 20 Ncm. The majority of the screws reached this nominal torque; however, a few screws fractured before reaching this value. Five screw types displayed plastic deformation below the threshold, at approximately 16 Ncm. Conclusions: The results suggest that orthodontic anchorage screws generally meet the requirements of the standard and ensure safe clinical use. However, according to the present data, it may be assumed that a portion of the screws will be plastically deformed upon removal.

KW - Biomechanics

KW - Deformation

KW - Orthodontic anchorage screw

KW - Patient safety

KW - Stability

UR - http://www.scopus.com/inward/record.url?scp=84964325618&partnerID=8YFLogxK

U2 - 10.1007/s00056-016-0032-6

DO - 10.1007/s00056-016-0032-6

M3 - Article

AN - SCOPUS:84964325618

SN - 1434-5293

SP - 1

EP - 9

JO - JOURNAL OF OROFACIAL ORTHOPEDICS

JF - JOURNAL OF OROFACIAL ORTHOPEDICS

ER -