平面导板在深覆(牙合)矫治中的临床应用研究

目的：探讨平面导板矫治重度深覆[牙合]患者的作用机制及临床作用要点。方法：对18名生长发育期的重度深覆[牙合]患者,用平面导板来打开咬合,并对咬合打开前后的硬软组织变化进行分析。结果：①上下后牙及牙槽高度均增加,下后牙及牙槽高度的增加值大于上后牙及牙槽高度的增加值,而对前牙及牙槽高度的影响无统计学差异;②上下颌骨在水平方向上无改变,但下颌平面角与下面高/全面高治疗后较治疗前增大,后面高/前面高治疗后较治疗前减小;③覆[牙合]减小,Spee氏曲线得到整平;④松弛的下唇肌肉得到紧张,从而改善了侧貌外形。结论：平面导板使覆[牙合]减小主要是后牙及后牙齿槽突高度增加的结果,对生长发育期的低角重度深覆[牙合]患者治疗效果较好。     

开（牙合）患者舌位置变化研究

目的：研究开He患者的舌位置有无特征性变异。方法：利用舌背碘油造影方法，增加头颅侧位定位X线片上舌背的显影效果，在头颅侧位定位X线片上以舌体在固有口腔内的相对位置确定舌体的位置，通过开He与正常He者知位置的团体t检验比较，找出开He患者的舌位置变异特性。结果：开He患者与正常He者比较，舌根部与悬雍垂之间的间隙增大，舌背部与腭表面之间的间隙减小，舌尖部更靠近牙齿，结论：开He个体相对于正常He个体舌位置有向前，向上的变化特点，这可能是开He的病因之一。     

前方牵引治疗安氏Ⅲ类骨性反(牙合)最佳矫治时机的研究

目的:进一步探寻前牵矫治器对以上颌发育不足为主的安氏Ⅲ类骨性反(牙合)患者的最佳矫治时机.方法:选取45例研究对象分成3组,即3～6岁组、7～10岁组、11～13岁组,每组各15例;采用上颌前方牵引进行治疗,拍摄治疗前后的头颅定位侧位片进行X线头影测量分析.结果:上颌前方牵引治疗对上述3个试验组的患者均产生了一定的矫治效果;上颌骨前移,下颌骨后旋,前牙反(牙合)纠正、覆合覆盖达正常、磨牙关系达中性关系;3组研究对象对比显示年龄最小的3～6岁组相对后两组具有更短的治疗时间(3.8±0.4)个月、更多的骨骼改变(69.5%)、更少的牙齿改变(31.5%)以及更少的副作用等优点(P＜0.05);11～13岁组相对前两组治疗时间较长(9±0.5)个月、骨骼改变较少(59.5%)牙齿的代偿性改变较多(41.0%,P＜0.05).结论: 前牵引治疗安氏Ⅲ类骨性反(牙合)矫治时机的选择在3～6岁组比7～10岁组效果好;7～10岁组比11～13岁组效果好.     

Partial trisomy 3q syndrome inherited from familial t(3;9)(q26.1; p23)

A five-year-old girl was referred to prometaphase chromosome analysis because of mental retardation, facial dysmorphic features suggestive of Cornelia de Lange syndrome, cleft palate and additional minor congenital malformations of the cardiac system and fingers and toes. A familial balanced translocation (3;9)(q26.1; p23) was found. The karyotype of the proposita was 46,XX,der(9),t(3;9)(q26.1;p23). Thus the patient was trisomic for 3q26.1-qter and monosomic for 9p23-pter. The unbalanced chromosome constitution was not detected by standard Q-banding analysis shortly after birth. The karyotype was misdiagnosed as 46,XX,9(p+) in the proposita and her mother, and thought to be a normal variant of chromosome 9. The repeated cytogenetic study led to the diagnosis of the translocation and to the possibility of prenatal diagnosis in the translocation carriers. A survey of 22 published cases of dup(3q) showed that nearly 60% were secondary to familial balanced rearrangements with an excess of maternally derived abnormal chromosomes 3. Red blood cell galactose-1-phosphate-uridyltransferase (GALT) activity was normal in the patient, consistent with previous assignment of the gene locus for GALT to 9p13 (Shih et al. 1982).     

腭裂修复术后患者与正常人群颅颌面形态的比较研究

应用X线头影测量方法对4～7岁时曾接受腭裂修复术的腭裂患者（现年龄为18～25岁）的颅颌面形态进行测量分析,将结果与湖北籍正常人群测量资料比较,结果表明腭裂修复术后患者颅底发育未受影响,面突角显著减少,上颌骨长度显著缩短,下颌角增大,下颌平面陡度增大,腭裂患者在4～7岁时接受手术治疗,至成年时存在不同程度的颅颌面发育畸形。     

不同错(牙合)类型患者面部软组织侧貌协调性研究

目的　研究 3种安氏错类型患者面部软组织的协调程度。方法　选择安氏 3种错患者的矫治前头颅定位侧位片各 2 0张 ,测量硬组织项目 1项和软组织项目 12项 ,测量结果用SPSS 10 .0软件进行统计学分析。结果　与安氏Ⅰ类错相比 ,安氏Ⅱ类 1分类错患者的上下唇突度增加 ,但整体面部凸度二者无差异 ;Ⅲ类错患者的上唇倾斜度增加 ,上颌发育不足 ,下唇形态、软组织面角及Z角与Ⅰ类错无差异。安氏Ⅱ类 1分类与安氏Ⅲ类错患者相比 ,除上唇倾斜度、鼻唇角、颏沟倾角、下唇_E线无显著差异外 ,其他指标均存在显著性差异。结论　3种错类型患者之间 ,唇部的位置和形态具有一定差异 ,但安氏Ⅱ类 1分类与安氏Ⅲ类错在整体面部协调方面可能存在一定程度的代偿机制 ;鼻唇角只能反映上唇本身的形态变化 ,不能直接反映面部侧貌的特征。     

Normal variation of mandibular asymmetry in children

Objective

To explore the normal variation of asymmetry in mandibles of children in the age group of 1 to 12 years.

Materials and Methods

The study group consisted of 92 cadaveric mandibles of children with a dental age of 1 to 12 years old in possession of ACTA (Academic Centre for Dentistry Amsterdam), Faculty of Dentistry, the Netherlands. 3D models of the mandibles were obtained from CT-scans and hemimandibular volumes of all mandibles were calculated. The condylar height, ramus height, mandibular body length and the gonial angle were bilaterally determined using a novel landmark-based method, and the degree of asymmetry was calculated.

Results

No relationship was found between dental age and asymmetry of the studied parameters (P < .05). The highest degree of asymmetry was found in the ramus height, whereas the gonial angle presented the lowest degree of asymmetry. A positive correlation was found between the asymmetry of the hemimandibular volume vs the height of the ramus (P < .05) and the length of the mandibular body (P < .05). An inverse correlation was found between the asymmetry of the ramus height vs the condylar height (P < .05), mandibular body length (P < .05) and gonial angle (P < .05).

Conclusions

Mandibular asymmetries in children did occur (9.8% of the included mandibles presented with a relevant overall asymmetry of ≥3%) and were unrelated to age. The different segments of the mandible seem to compensate for each other, in order to maintain a functional equilibrium.     

Validation of anatomically shaped cranial collimation (ACC) in orthodontic lateral cephalography

The use of an anatomically shaped cranial collimator (ACC) to reduce patient dose in orthodontic lateral cephalography was investigated in this study. The aim was to evaluate the potential interference of the ACC on landmark identification for orthodontic cephalometry. Consecutive orthodontic patients underwent a total of 100 cephalograms using an ACC mounted on a Veraviewepocs^® 3D X550 (J. Morita Co., Kyoto, Japan) X-ray unit. 10 observers were asked whether the identification of 5 landmarks close to the collimated area was hindered or rendered impossible by the presence of the collimator. Of the 500 landmarks that were judged by the 10 observers, 496 (99.2%) were reported to lack hindrance. In three landmarks, a minority of the observers reported hindrance. In 1 landmark, 8 of the 10 observers reported hindrance by the collimator. In no instance did the observers state that the identification of landmarks was impossible as a result of the collimation. Application of the ACC on the cephalostat of the X-ray unit is a viable way of reducing patient dose, as it only marginally interferes with the diagnostic yield of the exposure. The need to retake images when the ACC is applied was found to be extremely low.     

掩饰性治疗对成人骨性Ⅱ类错患者上气道及周围结构影响的研究

目的研究拔牙与非拔牙矫正对成人骨性Ⅱ类错气道及周围结构的影响,并分析可能的原因。方法选择36例成人骨性Ⅱ类错正畸结束病例,拔牙组20例,非拔牙组16例。用正颌外科模拟预测系统(CASSOS)软件测量患者治疗前后X线头颅侧位片,并对数据进行配对t检验。结果拔牙组与非拔牙组的腭后气道(Phw1-psp)与舌后气道(Phw2-Tb)在正畸前后均无显著变化(P>0.05)。非拔牙组的前颌间距离(Ant.ln Mx.Ht)与颌间面积(ln Mx Area)有所增加,差异有统计学意义。结论成人骨性Ⅱ类错畸形的掩饰性治疗,不论是否减数,在下前牙不过分内收的情况下,气道在矢状向的变化并不显著。