【作者】 李娜；

【导师】 刘琳；

【作者基本信息】 大连医科大学 ， 口腔医学（专业学位）， 2020， 硕士

【摘要】 目的:研究不同矢状骨面型患者上颌结节区的解剖形态,从而判断不同矢状骨面型的临界病例能否通过扩弓或磨牙远移达到正畸治疗目标,以及为提高上颌结节区微种植体的稳定性提供参考。材料与方法:选取58例就诊于大连医科大学附属大连市口腔医院,年龄≥20岁,单侧或双侧上颌第三磨牙完全埋伏阻生的患者。根据ANB角将其分为骨性Ⅰ类(平均年龄(24.6?6.1)岁)、骨性Ⅱ类(平均年龄26.1?9.6岁)、骨性Ⅲ类(平均年龄25.9?9.0岁)三组,每组上颌结节各28例。所有受试者均用Ka Vo 3D e Xam口腔锥形术影像系统(Cone-Beam Computed Tomography,CBCT)进行影像扫描,用Invivo Dental5软件将CBCT所得的DICOM数据进行三维重建,获得测量所需的矢状截面及轴截面,测量上颌结节区不同位置的长度与宽度。采用SPSS23.0软件对上颌结节的长度、宽度与上颌骨体的长度进行相关性分析,并对三组数据进行比较,P<0.05时其差异具有统计学意义。结果:(1)骨性Ⅰ类组上颌结节区不同位置的长度、宽度与骨性Ⅱ类组的差异无统计学意义(P>0.05),但是显著大于骨性Ⅲ类组(P<0.01);骨性Ⅱ类组上颌结节区不同位置的长度与宽度显著大于骨性Ⅲ类组(P<0.01);(2)本研究测得的上颌结节各处的宽度和长度,除矢状测量平面上距离上颌第二磨牙釉质牙骨质界(cemento-enamel junction,CEJ)根方3.0mm处牙根最远中至上颌结节最后缘的距离(L3)外,均与上颌骨体的长度呈显著正相关性;(3)上颌结节的长度在距离CEJ根方3.0mm处最短,测量的所有上颌结节L3处的平均值为(8.47?1.50)mm,最小值为4.79mm,骨性Ⅰ类L3的平均值为(8.81?1.44)mm,最小值为5.73mm;骨性Ⅱ类L3的平均值为(9.22?1.35)mm,最小值为6.39mm;骨性Ⅲ类L3的平均值为(7.40?1.08)mm,最小值为4.79mm;矢状测量平面上距离上颌第二磨牙CEJ根方6.0mm处牙根最远中至上颌结节最后缘的距离(L6)、矢状测量平面上距离上颌第二磨牙CEJ根方9.0mm处牙根最远中至上颌结节最后缘的距离(L9)均明显长于L3,L6与L9数值相接近;测得轴截面上距离上颌第二磨牙最远中3.0mm处上颌结节颊腭侧皮质板间的距离(W3)最大,平均值为(12.81?1.19)mm,最小值为10.17mm,并且向远中逐渐减小。结论:上颌结节区的骨量与上颌骨的生长发育密切相关,其长度、宽度均与上颌骨体的长度具有显著相关性。骨性Ⅰ类、骨性Ⅱ类患者上颌结节的长度与宽度均大于骨性Ⅲ类,但骨性Ⅰ类与骨性Ⅱ类无明显差异。上颌结节在距离CEJ根方3.0mm处长度最短,为正畸临床上上颌磨牙远移距离的多少提供参考,骨性Ⅲ类患者磨牙远移要更加受到上颌结节骨量的限制,因此骨性Ⅲ类需要正畸正颌联合治疗的患者在选择磨牙远移的方案去除上颌前牙代偿时要更加慎重。上颌结节区的宽度由第二磨牙远中向上颌结节后缘逐渐缩窄,并且骨性Ⅲ类变化的更加明显,正畸临床上进行磨牙远移时不仅要考虑上颌结节区的长度,还要考虑其宽度,若宽度不足,牙列远移过程中可能与骨皮质接触,从而影响牙列远移量,严重者会导致骨开窗、骨开裂,甚至出现牙根吸收。因此,正畸临床上通过磨牙远移解决拥挤或前突时,仅通过曲面断层片或头颅侧位片分析上颌结节区的骨量是不准确的,需要对上颌结节的三维结构进行精确分析,评估上颌结节区的骨量以及牙齿可远中移动的量,从而获得更加科学有效的治疗方案。更多还原

【Abstract】 Objective:To study the anatomy of maxillary tuberosity in patients with different sagittal skeletal types,in order to determine whether the critical cases of different sagittal bone types can achieve the treatment goal by expanding the arch or moving the molars far distally,and provide reference for the stability of the micro-implant in the maxillary tuberosity.Materials and Methods:Fifty eight patients(age≥20)with unilateral or bilateral impacted maxillary third molars were selected from Dalian Stomatological Hospital Affiliated to Dalian Medical University.According to the size of ANB angle,they were divided into three groups of sagittal skeletal facial type.The average age of class I was(24.6±6.1)years,class II was(26.1±9.6)years,class III was(25.9±9.0)years.Each group included 28 maxillary tuberosities.All subjects were scanned by Ka Vo 3D e Xam cone beam computed tomography(CBCT).The DICOM data from CBCT were reconstructed by Invivo Dental5 software,were all measurement plane were obtained and and utilized to measure the length and width of different positions of the maxillary tuberosities.Finally,spss23.0 software was used to analyze the correlation between the length and width of the maxillary tuberosity and the length of the maxillary arch.The data of the three groups were compared in two groups,and the difference was statistically significant when p < 0.05.Result:(1)There was no significant difference in the length and width of different positions of the maxillary tuberosities between the class I and the class II(P > 0.05),butit was significantly greater than that of class III group(P < 0.01).The length and width of different positions of the maxillary tuberosities in the class II group were significantly larger than class I(P < 0.01);(2)The width and length of the maxillary tuberosity measured in this study were positively correlated with the length of the maxillary body,except for the distance measured at 3.0 mm apical to the cemento-enamel junction(CEJ)on the sagittal view from the most distal point of the root of the upper second molar to the posterior margin of the maxillary tuberosity(L3);(3)The length of the maxillary tuberosity is the shortest at the distance of 3.0mm apical to the CEJ.For all the maxillary tuberosities,the average value of L3 was(8.47 ± 1.50)mm,the minimum value was 4.79 mm.The average value of L3 was(8.81±1.44)mm and the minimum value was 5.73 mm in class I,(9.22±1.35)mm and6.39 mm in class II,(7.40±1.08)mm and 4.79 mm in class III.The distance measured at6.0 mm apical to the CEJ on the sagittal view from the most distal point of the root of the upper second molar to the posterior margin of the maxillary tuberosity(L6)and the distance measured at 9.0 mm apical to the CEJ on the sagittal view from the most distal point of the root of the upper second molar to the posterior margin of the maxillary tuberosity(L9)were significantly longer than L3,L6 is close to L9.The distance measured at 3.0 mm distal to the the upper second molar on the axial plane from the buccal cortex to palatal cortex(W3)was the largest,the average was(12.81±1.19)mm,the minimum was 10.17 mm,and the width gradually decreases from mesial to distal.Conclusion:The bone mass in the tuberosity area is closely related to the growth and development of the maxilla,and its length and width are significantly related to the length of the maxilla.The length and width of maxillary tuberosity in patients with class I and the class II group were larger than those of class III,but there was no significant difference between class I and the class II.The length of maxillary tuberosity is the shortest 3.0 mm from the root of CEJ,which can provide a reference for the amount of molars distalization in clinical.The molars distalization of the patients with skeletal class Ⅲ should be more limited by the bone mass of the maxillary tuberosities.Therefore,the patients with skeletal class Ⅲ who need the combined treatment ofOrthodontics and orthognathic should be more careful when choosing the scheme of molars distalization to remove the compensation of the maxillary anterior teeth.In addition,the width of maxillary tuberosity gradually decreases from mesial to distal,and the change of class Ⅲ was more obvious.In orthodontic clinical teratment,the length and width of tuberosity should be taken into account when the molars are moved far away distally.If the width is not enough,it may contact with bone cortex during distalization,which may affect the amount of distalization.In serious cases,it may lead to bone fenestration,dehiscence,and even roots resorption.Therefore,it is inaccurate to analyze the bone mass in the maxillary tuberosity only by curved section or lateral cephalogram when we solve the crowding or protrusion by molars distalization.In order to obtain a more scientific and effective treatment plan,we need to accurately analyze the anatomical structure of the tuberosity,and evaluate the bone mass of maxillary tuberosity and the amount of the distal movement.更多还原