Invisible orthodontic treatment is an effective form of malocclusion treatment favored in recent years.The magnitude of its orthodontic force has a crucial impact on the outcome of the treatment and has gained a high ...Invisible orthodontic treatment is an effective form of malocclusion treatment favored in recent years.The magnitude of its orthodontic force has a crucial impact on the outcome of the treatment and has gained a high level of clinical interest.However,there are very few explorations of in vivo measurements of orthodontic force,and existing studies are limited to a large number of couplings,which are inconvenient for clinical use.In this work,we developed a wireless flexible measurement system that allows quantitative measurement of the orthodontic force of an invisible aligner on a dental model.The system is wireless,tiny,flexible,fast responding,and has a range suitable for the range of orthodontic forces.We show the difference in the orthodontic force applied to different tooth positions and the difference in the orthodontic force applied to different positions of the same tooth.In addition,the system can evaluate the mechanical differences between aligners of different brands and materials as well as the deviation of fabrication results.This system provides a test tool and evaluation method for future real-time assessment of clinical orthodontic forces.展开更多
Orthodontic forces can cause stress and strain concentration and microcracks on tooth root surfaces.This study aimed to analyze whether a lingual orthodontic appliance was more likely to cause root stress concentratio...Orthodontic forces can cause stress and strain concentration and microcracks on tooth root surfaces.This study aimed to analyze whether a lingual orthodontic appliance was more likely to cause root stress concentration and root resorption than the traditional buccal appliance.A finite element model of the root of the maxillary central incisor with straight,buccal,and lingual curvatures was established.A load perpendicular to the tooth surface on the buccal and lingual surfaces of the central incisor was applied,and the stress and strain concentration at the root apex was compared.The stress and strain at the root apex of the lingual cingulum group were lesser than those of the buccal group;little difference was observed between the lingual and buccal clinical crown central augmentation groups.The stress and strain at the root apex of the lingual direction movement group were greater than those of the buccal direction movement group.The direction of the root curvature also influenced the amount of stress and strain at the root apex.The difference in the risk of root resorption between lingual and buccal orthodontics is dependent on the height of the bracket placement.The loading direction of the orthodontic force and direction of the root curvature also affect the stress and strain at the root apex.展开更多
基金Beijing Natural Science Foundation(L232109)National Natural Science Foundation of China(No.12202274 and No.52171234)+1 种基金Fundamental Research Funds for the Central Universities(YWF-22-K-101)National Key Research and Development Project(Nos.2021YFC2400703 and 2019YFE0101100).
文摘Invisible orthodontic treatment is an effective form of malocclusion treatment favored in recent years.The magnitude of its orthodontic force has a crucial impact on the outcome of the treatment and has gained a high level of clinical interest.However,there are very few explorations of in vivo measurements of orthodontic force,and existing studies are limited to a large number of couplings,which are inconvenient for clinical use.In this work,we developed a wireless flexible measurement system that allows quantitative measurement of the orthodontic force of an invisible aligner on a dental model.The system is wireless,tiny,flexible,fast responding,and has a range suitable for the range of orthodontic forces.We show the difference in the orthodontic force applied to different tooth positions and the difference in the orthodontic force applied to different positions of the same tooth.In addition,the system can evaluate the mechanical differences between aligners of different brands and materials as well as the deviation of fabrication results.This system provides a test tool and evaluation method for future real-time assessment of clinical orthodontic forces.
基金This work was supported by the National Natural Science Foundation of China(No.U20A20390 and 11827803).
文摘Orthodontic forces can cause stress and strain concentration and microcracks on tooth root surfaces.This study aimed to analyze whether a lingual orthodontic appliance was more likely to cause root stress concentration and root resorption than the traditional buccal appliance.A finite element model of the root of the maxillary central incisor with straight,buccal,and lingual curvatures was established.A load perpendicular to the tooth surface on the buccal and lingual surfaces of the central incisor was applied,and the stress and strain concentration at the root apex was compared.The stress and strain at the root apex of the lingual cingulum group were lesser than those of the buccal group;little difference was observed between the lingual and buccal clinical crown central augmentation groups.The stress and strain at the root apex of the lingual direction movement group were greater than those of the buccal direction movement group.The direction of the root curvature also influenced the amount of stress and strain at the root apex.The difference in the risk of root resorption between lingual and buccal orthodontics is dependent on the height of the bracket placement.The loading direction of the orthodontic force and direction of the root curvature also affect the stress and strain at the root apex.
