CAJ | 학술논문

目的：研究在差动直丝弓矫治技术打开咬合过程中,不同下颌磨牙后倾弯角度对下颌前牙应力分布及位移趋势的影响。方法利用志愿者锥体束CT,建立下颌牙列和差动直丝弓矫治器的三维有限元模型,模拟下颌30°、35°、40°和45°四种后倾弯,对模型加载进行有限元分析。结果下颌前牙牙根和牙周膜所受应力均随后倾弯度数增大而增大,当后倾弯角度大于40°时应力出现减小,其应力分布符合非控制性倾斜移动的特点。下颌前牙的初始位移趋势随后倾弯的增大而增大,当大于40°时初始位移趋势开始减小。下颌尖牙在颊舌向上表现为冠颊倾,下颌切牙冠唇倾,在垂直向上表现为先尖牙再切牙的顺序压低,在近远中向均表现为冠近中移动趋势。结论在差动直丝弓打开咬合阶段,通过调整磨牙后倾曲的角度可获得下颌前牙段适宜的压入以及匹配的上下颌牙弓宽度。
목적：연구재차동직사궁교치기술타개교합과정중,불동하합마아후경만각도대하합전아응력분포급위이추세적영향。방법이용지원자추체속CT,건립하합아렬화차동직사궁교치기적삼유유한원모형,모의하합30°、35°、40°화45°사충후경만,대모형가재진행유한원분석。결과하합전아아근화아주막소수응력균수후경만도수증대이증대,당후경만각도대우40°시응력출현감소,기응력분포부합비공제성경사이동적특점。하합전아적초시위이추세수후경만적증대이증대,당대우40°시초시위이추세개시감소。하합첨아재협설향상표현위관협경,하합절아관진경,재수직향상표현위선첨아재절아적순서압저,재근원중향균표현위관근중이동추세。결론재차동직사궁타개교합계단,통과조정마아후경곡적각도가획득하합전아단괄의적압입이급필배적상하합아궁관도。
Objective To investigate the stress distribution and movement tendency of the mandibular incisor and canine by different tip back bend in the phase of bite opening with tip-edge plus system. Methods The finite element models of mandible from CBCT of the volunteer was established to simulate the bite opening treatment with 30°,35°,40°, 45° tip back bend. Results The stress of mandibular anterior teeth and periodontal membrane was increased with the increase of the bending degree of the tooth. When the degree of tip back bend exceeded 40°, the stress started to decline, and the stress distribution accorded with the characteristics of the uncontrolled tipping. The crown of mandibular canine tipped buccally and mesially, the mandibular incisor tipped labially. The intrusion occured vertically in canine first and then in incisors. Conclusion To intrude the anterior teeth efficiently in mandible, the proper tip back bend shoud be chosen by tip edge plus system. .