单侧后牙反(牙合)者髁突侧向运动轨迹的研究

目的 通过记录单侧后牙反（牙合）者与正常（牙合）者下颌侧向运动时髁交在三雏方向上的运动轨迹，探讨单饲后牙反（牙合）者髁突饲向运动轨迹的特征，揭示其与正常（牙合）之间的差异。方法 正常（牙合）15例，单饲后牙反（牙合）7例。应用计算机化的髁突运动轨迹描记仪（computer-Aided Axiography，CADIAX）Ⅰ型以及分析软件（Gamma Dental Software for Windows 2．3．2．22，GDSW）记录下颌做左右饲向运动时髁突在水平面及矢状面上的 运动轨迹。结果实验组侧向运动中非工作侧矢状向最大位移量显著小于正常对照组，工作侧髁突向后运动的幅度大于正常对照组。结论 单侧后牙反（牙合）者髁突侧向运动轨迹形态与正常（牙合）有明显差异，其两侧关节囊、韧带松驰。     

单侧后牙锁患者前伸及后退髁突运动轨迹的研究

目的探讨单侧后牙锁者在下颌前伸、后退运动过程中髁突运动轨迹的特征及其与正常者之间的差异。方法选择单侧后牙锁患者24例和个别正常25例,应用髁突运动轴图描记仪(computer aided diagnosis axiograph,CADIAX)记录下颌前伸、后退运动时髁突的运动轨迹。结果实验组在下颌前伸、后退运动过程中髁突轨迹曲折、不流畅、重合性差,两侧髁突运动不对称、侧方位移增大;其锁侧在矢状方向和空间位移上以及髁突矢状面倾斜度小于非锁侧(P<0.05),锁侧髁突矢状面倾斜度较对照组小(P<0.05),在髁突位移5mm处水平面髁突倾斜度大于对照组(P<0.05)。结论单侧后牙锁者下颌前伸、后退运动时两侧髁突运动不对称,侧方位移增加。     

单侧后牙反(牙合)髁突前伸运动轨迹的研究

目的:探讨单侧后牙反牙合髁突前伸运动轨迹的特征并比较与正常牙合之间的差异。方法:正常牙合5人,单侧后牙反牙合7人,采用计算机化的髁突运动轨迹Ⅰ型描记仪及分析软件,记录下颌最大前伸运动时髁突在水平面及矢状面上的运动轨迹。结果:单侧后牙反牙合者前伸后退运动轨迹多不重合,反牙合侧前伸髁道斜度明显大于对侧。结论:单侧后牙反牙合者存在前伸牙合干扰,其两侧颞下颌关节不对称。     

单侧后牙正锁(牙合)患者下颌侧方运动时的髁突轨迹特征

目的:探讨单侧后牙正锁(牙合)患者在下颌侧方运动过程中髁突的运动轨迹特征及其与正常(牙合)者之间的差异.方法:选取单侧后牙正锁(牙合)患者26例为实验组,个别正常(牙合)26例为对照组,应用髁突运动轴图描记仪(computer aided diagnosis axiograph,CADIAX)记录下颌侧方运动时髁突的运动轨迹.实验数据采用SPSS10.0软件包分析,选用成组t检验、配对t检验或秩和检验比较组间差异有无统计学意义.结果:实验组下颌侧方运动过程中髁突轨迹不流畅变异大,两侧运动轨迹不对称.非锁(牙合)侧髁突的矢状位移、垂直位移以及空间最大位移大于锁(牙合)侧和对照组,水平位移小于后者,差异有统计学意义(P<0.05);非锁(牙合)侧髁突的矢状倾斜度大于锁(牙合)侧和对照组,水平倾斜度小于后者,差异有统计学意义(P<0.05).结论:单侧后牙正锁(牙合)患者下颌侧方运动过程中两侧髁突运动轨迹不对称.     

单侧后牙反患者髁状突及下颌升支对称性的螺旋CT研究

目的:探讨单侧后牙反成年患者髁状突及下颌升支的对称性。方法:对22例单侧后牙反患者进行螺旋CT扫描、多层面重建和相关参数测量,并进行统计分析。结果:双侧髁突内、外突点的距离,髁突内倾角及下颌角点的距离有显著差异,但髁突左右径、髁状突最大横截面积、下颌支高度及下颌支冠状位最大面积的差异无统计学意义。结论:单侧后牙反患者左右侧髁状突及下颌支的位置不对称,但髁突及下颌升支大小无显著差异。     

Forsus矫治器对骨性Ⅱ类错袷下颌矢状运动时髁突轨迹影响的初步分析

目的探讨Forsus矫治器对骨性Ⅱ类错[牙合]下颌矢状运动时髁突轨迹的影响方法选取骨性Ⅱ类错[牙合]患者10例作为实验组，10例安氏Ⅰ类患者为对照组。应用髁突运动轨迹轴图描记仪，对实验组戴用Forsus矫治器前后及对照组下颌矢状运动时的髁突运动轨迹进行检查和记录，对结果进行定性定量分析。结果实验组戴用Forsus矫治器前后，髁突的垂直向位移和旋转度比对照组均偏大（P〈0．01），而实验组矫治前后髁突的垂直向位移和旋转度均无显著性差异（P〉0．05）。结论短期使用Forsus矫治器对Ⅱ类错[牙合]患者的髁突轨迹无明显影响。     

儿童功能性单侧后牙反患者的髁突对称性及矫治后髁突位置变化的研究

目的探讨儿童功能性单侧后牙反患者的髁突对称性及上颌扩弓治疗后髁突位置的变化。方法选择22例通过上颌扩弓成功矫治的功能性单侧后牙反儿童患者,男10例,女12例,年龄6.0-8.5岁,平均7.5岁作为实验组。另选择22例正常患者,男11例,女11例,年龄6.5-9.0岁,平均7.5岁作为对照组。反组矫治前后与对照组患者均拍摄曲面断层片和双侧闭口位矫正薛氏位片,测量髁突形态的不对称指数和髁突在关节窝中的相对位置。用SPSS 12.0软件进行统计分析。结果反组患者两侧髁突形态无明显不对称,与对照组相比,髁突高度(CH)、升支高度(RH)以及两者之和(CH+RH)的不对称指数均无统计学差异。反组矫治前(T1)两侧髁突在关节窝中的位置有明显差异,非反侧关节前间隙减小(P<0.05),上后间隙增大(P<0.05)。非反侧髁突在关节窝中的位置(R)相对反侧更加靠前(P<0.01)。矫治后(T2)双侧髁突位置变得相对对称。结论儿童功能性单侧后牙反患者的髁突形态相对对称,而髁突位置存在不对称性,说明下颌向反侧发生功能性偏斜,而这种偏斜并未导致髁突发生骨性不对称;正畸治疗可使两侧髁突位置更加协调。     

下颌前突患者下颌支矢状劈开截骨术后髁突运动轨迹的改变

目的:研究双侧下颌支矢状劈开截骨术对下颌前突患者髁突运动轨迹的影响。方法:采用ARCUSdigma下颌三维运动轨迹描记仪,以髁突运动中心为参考点,研究30例正常受试者、14例下颌前突患者手术前后开口、前伸和左右侧向髁突运动的轨迹。用SPSSV11.0统计软件包进行配对t检验和成组t检验。结果:下颌前突患者术前、术后、正常组左侧髁突的运动轨迹与右侧基本相同,左侧髁突与右侧的开口、前伸和侧方运动范围无显著性差异(P>0.05)。术前组与正常组髁突运动轨迹差别较大,术前开口、前伸和侧方运动范围均小于正常组(P<0.05);术后与正常组髁突运动轨迹接近,术后开口、前伸和侧方运动范围与正常组无统计学差异;术前与术后组髁突运动轨迹差别较大,术前开口、前伸和侧方运动范围均显著小于术后组(P<0.05)。结论:下颌前突患者手术后,随着术后正畸治疗及咬合自我调整,建立了正常的咬合引导关系,使下颌功能运动趋向正常。     

Forsus矫治器对骨性Ⅱ类错(牙合)下颌矢状运动时髁突轨迹影响的初步分析

目的 探讨Forsus矫治器对骨性Ⅱ类错(牙合)下颌矢状运动时髁突轨迹的影响方法选取骨性Ⅱ类错(牙合)患者10例作为实验组,10例安氏Ⅰ类患者为对照组.应用髁突运动轨迹轴图描记仪,对实验组戴用Forsus矫治器前后及对照组下颌矢状运动时的髁突运动轨迹进行检查和记录,对结果进行定性定量分析.结果 实验组戴用Forsus矫治器前后,髁突的垂直向位移和旋转度比对照组均偏大(P＜0.01),而实验组矫治前后髁突的垂直向位移和旋转度均无显著性差异(P＞0.05).结论 短期使用Forsus矫治器对Ⅱ类错(牙合)患者的髁突轨迹无明显影响.     

颜面不对称患者开闭口时的髁突运动轨迹特征

目的通过记录颜面不对称患者的髁突运动轨迹,研究颜面不对称患者的髁突运动规律.方法颜面不对称患者24人,其中男性9人,女性15人.使用CADIAXⅢ型(Computer Aided Diagnosis Axiograph)髁突运动记录仪,记录患者在不同下颌运动时的髁突运动轨迹,对开闭口运动时的髁突运动轨迹特征进行分析.结果颜面不对称患者双侧髁突开闭口轨迹具有不对称性,偏斜侧(下颌颏部所偏向的一侧)的轨迹弧度大于非偏斜侧,定量分析大张口时双侧髁突的运动距离、矢状面、水平面的倾斜度没有显著性差异,在髁突运动5mm时双侧髁突在矢状面、水平面的倾斜度偏斜侧大于非偏斜侧,具有显著性差异.髁突铰链轴的旋转度比正常(牙合)人群要高.结论颜面不对称患者不仅具有形态结构的不对称,髁突运动轨迹在长度、角度等方面也呈现一定的不对称性.     

儿童单侧后牙反患者下颌及颞颌关节的对称性研究

目的研究儿童单侧后牙反牙合患者下颌及颞颌关节的对称性。方法以26例替牙期单侧后牙反牙合患儿为试验组,28名正常牙合替牙期儿童为对照组,分别摄定位颏顶位片及双侧颞颌关节中位断层片进行比较。结果替牙期单侧后牙反牙合患儿在下颌骨坐标系中DMP点更靠颊侧。在颅底坐标系中,反牙合侧DMP点更靠远中,DMP、MM、DM点更靠颊侧。双侧髁突位置不对称、非反牙合侧关节前间隙减小,上后间隙均增大。结论相对于下颌坐标系,反牙合侧第一磨牙位置与对侧相比更靠远中及颊侧。在骨性结构上,未见下颌的不对称。试验组双侧髁突位置及关节间隙有差异,说明下颌发生功能性侧方移动。     

Mandibular movement and frontal craniofacial morphology in orthognathic surgery patients with mandibular deviation and protrusion

The present study was conducted to investigate the relationship between mandibular movement (lateral excursion and masticatory movements) and craniofacial morphology in 16 patients with mandibular deviation, using a six degrees-of-freedom measuring device. (i) Mandibular deviation was found to be significantly related to frontal maxillary and occlusal plane angles. (ii) Three-dimensional non-working condylar and incisal path lengths were longer during the lateral excursion to the non-deviated side than to the deviated side, and the incisal path moved antero-inferior. (iii) The lateral motion range of the incisal path was wider during masticatory movement on the non-deviated side than on the deviated side, and the molar and non-working condylar path lengths corresponding to the lateral range of the incisal path were also longer on the non-deviated side. The group with posterior crossbite showed a significantly smaller horizontal range of incisal path, and also significantly smaller frontal projected incisal and molar path angles during masticatory movement on the deviated side than on the non-deviated side. These results suggest that lateral excursion and masticatory movements could be related to craniofacial morphology and posterior crossbite.     

Movement of the lateral and medial poles of the working condyle during mastication in patients with unilateral posterior crossbite.

Patients with unilateral posterior crossbite often show reverse sequential jaw movement patterns on the frontal view during mastication on the crossbite side. Recent studies show that such patients are prone to suffer from temporomandibular joint (TMJ) disc displacement, particularly the lateral portion. The purpose of this study was to examine the movement of the lateral and medial poles of the working condyle during mastication in such patients. Subjects were 12 consecutive patients with unilateral posterior crossbites and without TMJ disc displacements and 12 normal subjects. An optoelectronic jaw-tracking system with 6 degrees of freedom was used to record the motion of the lateral and medial poles of the working condyle during mastication of standardized hard, gummy jelly. The data from the first 10 cycles were analyzed. The lateral and medial poles of the condyle on the crossbite side moved more in the medial direction and less in the lateral direction during mastication in the crossbite patients than the condyle in the normal subjects. The lateral pole of the working condyle moved more in the posterior and inferior directions and less in the anterior direction than the medial pole in all subjects. These results suggest that these condylar movements in patients with unilateral posterior crossbites might be related to the susceptibility to TMJ disc displacement, particularly the lateral portion.     

Reverse-sequencing chewing patterns evaluation in anterior versus posterior unilateral crossbite patients

It is well established that patients with a unilateral posterior crossbite exhibit reverse-sequencing chewing patterns when chewing on the affected side. The aim of the study was to compare the prevalence of reverse-sequencing chewing cycles in patients with anterior versus posterior unilateral crossbite during chewing soft and hard boluses. Eighty-six children (39 boys, 47 girls) were included in the study: 26 (10.4 ± 2.7 years) with unilateral anterior crossbite, 43 (10.2 ± 4.2 years) with unilateral posterior crossbite, and 17 (10.6 ± 2 years) with normal occlusion were selected for the study. Mandibular movements were measured with a kinesiograph (K7, Myotronics Inc. Tukwila). The kinematic signals were analyzed using custom-made software. The results showed a low prevalence of reverse-sequencing chewing cycles in patients with anterior crossbite, without any significant difference between sides and with the control group, with both soft (P = 0.33) and hard (P = 0.29) bolus. The patients with posterior unilateral crossbite showed a significant higher prevalence of reverse-sequencing chewing cycles during chewing on the crossbite side with respect to the non-crossbite side (P < 0.001) and to the control group (P < 0.001). Comparing the patients with anterior versus posterior unilateral crossbite, a significant difference (P < 0.001) in the prevalence of reverse chewing cycles was demonstrated during chewing on the posterior crossbite side only with both soft and hard bolus. In conclusion, patients with anterior versus posterior unilateral crossbite show different functional characteristics depending on which dental region is involved.     

偏颌畸形患者的牙弓特征

目的　分析偏颌畸形患者的牙弓特征,为临床矫治提供参考。方法　采用三维坐标测量仪在20例偏颌 畸形患者(试验组)和20例正常人(对照组)的牙模型上测量上下颌尖牙、前磨牙和磨牙牙尖的三维坐标值,分 析牙弓矢向和横向的对称性、上下牙弓的协调性和牙齿倾斜度,采用SAS 6·03进行统计学检验。结果　试验组上 颌尖牙和第一前磨牙距腭中缝的距离偏向侧大于偏离侧(P<0·05),下颌从尖牙到第二磨牙偏向侧距中线的距离 小于偏离侧(P<0·05);上颌尖牙和第一前磨牙的牙弓宽度比率较对照组小(P<0·05),而上颌第二前磨牙和第一 磨牙的牙弓宽度比率与正常无统计学差异(P>0·05);上颌后牙偏向侧颊向倾斜度大于偏离侧,下颌后牙偏向侧 舌向倾斜度大于偏离侧(P<0·05);上颌偏向侧和偏离侧牙齿的矢向位置无统计学差异(P>0·05)。结论　偏颌畸 形患者上牙弓前部窄于下牙弓,上颌牙齿矢向位置无差别,而上下颌两侧后牙颊舌向倾斜度存在明显差异。     

Functional unilateral posterior crossbite effects on mastication movements using axiography

This prospective study investigated the influence of functional unilateral posterior crossbite on mastication movements. The study group included 16 patients (nine girls and seven boys) with functional unilateral posterior crossbite involving three or more posterior teeth. A control group comprised 15 individuals (nine girls and six boys) with normal occlusion and the mean age of both groups was 9.17 years. The mandibular masticatory movements were registered, using computer axiography, for 30 seconds during chewing to determine the preference side of chewing. The patterns of the first, third, and fifth chewing cycles were compared with the preference side to establish whether they would predict the chewing preference side. The extent of the maximal lateral and vertical displacements of the mandible during chewing were compared between study and control groups. This study found that overall the left side was the preferred mastication side in 43.7% of individuals in the study and 46.7% in the control group. There was no relationship between the side of the crossbite and the masticatory preference side (Mc Nemar test, P = .5). No correlation was present between the patterns of chewing movements in the first, third, or fifth cycles. Both study and control groups showed similar maximal lateral and vertical mandible displacement.