微螺钉支抗改善露龈笑临床分析

目的：分析微螺钉种植体作为支抗矫治露龈笑的临床效果。方法：选择13名露龈笑患者,在其两侧上颌侧切牙与尖牙之间靠近牙根部植入微螺钉,用橡皮圈-结扎丝将微螺钉与上颌中切牙和侧切牙连起来,每侧即刻加力100g,每4周更换一次橡皮圈。矫治前后通过测量,比较露龈笑及上切牙压低程度。结果：平均疗程5.8个月,上切牙龈缘到上唇下缘距离平均缩短4.27mm,露龈笑得到改善。结论：微螺钉种植体作为支抗性能稳定,疗效肯定,操作简单,是矫治露龈笑的理想支抗选择。     

种植支抗治疗露龈笑过程中切牙牙根吸收的CBCT检测

目的　通过CBCT技术精确测量种植支抗治疗露龈笑过程中所导致的上颌切牙牙根吸收的情况。方法　11例患者全部采用直丝弓矫治技术,在上颌两侧侧切牙和中切牙之间的牙槽骨上,各植入1枚微螺钉,每侧约0.98 N压低上前牙。当龈缘距与微笑线基本平齐时,治疗停止,进入保持阶段。治疗前后拍摄CBCT,在矢状位图像选取牙根长度最长的轴面进行长度测量。结果　所有患者露龈笑均有明显改善,平均减小(2.47±0.64)mm,切牙压入量为(2.81±0.62)mm。CBCT显示,治疗前后切牙牙根有一定程度的吸收,其中中切牙的吸收量大于侧切牙,但没有统计学意义。结论　采用种植支抗治疗露龈笑会导致上颌切牙出现牙根吸收,CBCT能够定量测量根吸收的情况。     

露龈笑患者上颌前牙区牙槽骨形态的研究

目的 通过锥形束CT(cone-beam computed tomography,CBCT)扫描测量露龈笑患者上颌前牙区牙槽骨,探讨露龈笑患者的牙槽骨解剖特征,为微种植钉的植入提供参考.方法 选取63例临床表现露龈笑的成年患者,CBCT扫描并三维重建.在距离牙槽嵴顶4 mm、6 mm、8 mm高度的3个层面上分别测量上颌前牙区相邻两牙根间的近远中向、唇腭向骨质厚度及唇侧皮质骨厚度.结果 在相邻两牙之间,近远中向牙根间的距离随测量高度的增加逐渐增加(P<0.05).中切牙与侧切牙间的牙根间距离最小(P<0.05).两中切牙间唇腭向根间骨厚度最薄(P<0.05).中切牙与侧切牙间、侧切牙与尖牙间的根间骨厚度差异无统计学意义(P>0.05).在相邻两牙之间,唇侧根间皮质骨厚度随测量高度增加而增加(P<0.05).两中切牙根间唇侧骨皮质最薄(P<0.05),侧切牙与尖牙间骨皮质厚度最厚(P<0.05).结论 牙根间近远中向骨厚度、唇腭向骨厚度和唇侧皮质骨厚度随高度增加而增加,且在侧切牙与尖牙间最厚.尖牙与侧切牙间的骨质区域可以考虑作为植入微种植钉的部位.     

微种植体支抗压低上前牙治疗露龈笑

目的探讨应用微种植体支抗治疗上前牙槽骨垂直向发育过度的露龈笑患者,改善牙龈显露的程度。方法选取16例因上前牙槽骨垂直向发育过度导致露龈笑的患者,在侧切牙与尖牙间植入微种植体支抗,施加100g力压低上前牙。治疗前后分别收集头颅定位侧位片、上前牙的根尖片、牙模型、微笑时面下1/3照片及上前牙的龈沟深度;对实验结果进行统计分析。结果压低时间为(6.7±1.2)个月。(1)牙龈显露减少(2.3±0.5)mm;(2)头影测量分析显示,上中切牙阻力中心点压低(2.6±0.3)mm,覆减少(2.8±0.6)mm,切缘与腭平面的距离减少(3.1±0.7)mm,鼻唇角增加(5.4±2.9)°,P<0.05;(3)压低结束时,上前牙的临床牙冠变短,未见明显牙根吸收。结论应用微种植体支抗可以有效地压低上前牙,改善露龈笑,但牙龈的改建速度比牙齿的压低速度慢。     

助攻型微钛钉种植体支抗压低上切牙的初步应用

目的:探讨微钛钉种植体支抗压低上切牙、改善前牙深覆及龈笑的临床效果。方法:选择一例因上齿槽发育过度导致前牙深覆及龈笑的青年女性患者,将两枚微型助攻钛钉种植体分别植入患者上颌两侧中切牙和侧切牙根尖上方的牙槽骨内,以链状橡皮连接种植钉与上颌弓丝使上切牙压低,每侧50克力,每月复诊一次,疗程为4个月,治疗前后均拍摄X线投影测量片进行分析。结果:U1-PP距减小,前牙深覆从Ⅱ。减少到Ⅰ。;龈笑改善。结论:微钛钉种植体可以作为有效的正畸支抗压低上切牙。     

微型自攻钛钉种植体支抗压低切牙的初步应用研究

目的介绍微型自攻钛钉种植体用于正畸支抗的临床经验,评价自攻型微型钛钉种植体作为垂直向支抗压低前牙的有效性.材料方法在26例采用微型自攻钛钉种植体作为支抗手段的临床病例中,选择3名患者(年龄20-25岁),均表现为上颌或下颌前部牙齿槽发育过度,采用微型种植体支抗压低前牙.种植体植入上颌中切牙和侧切牙之间的牙槽间隔或下颌侧切牙和尖牙之间的牙槽间隔,每侧以50克力压低前牙.比较压低治疗前后的X线头颅侧位片,测量前牙切缘的压低量和转矩的改变量.结果所有病例治疗后前牙覆(牙合)达到正常,切缘平均压低4.3毫米,转矩平均增加9.8度.治疗过程中所有微型种植体均保持了稳定,种植体周围软组织健康.结论微型自攻钛钉种植体能够作为稳定的骨性正畸支抗,压低前牙,改善覆(牙合)和龈笑.并且具有操作简单灵活,可即刻加力,不依赖患者合作的优势.     

应用微种植体支抗压低上前牙改善露龈笑的临床研究

目的 探讨上颌前牙区微种植体支抗压低上前牙改善露龈笑的临床疗效。方法 选择露龈笑伴深覆患者15例,平均年龄（19.7±5.4）岁,在位于12,22近中根尖处颌骨内各植入1颗微种植钉,在方丝12,22近中置游离拉钩,向微种植钉做弹性牵引,每侧加力0.6 N,平均加力压低的时间为(6.2±1.6)个月。测量矫治前后X 线头颅侧位片的相关软硬组织指标,使用SPSSl3.0 软件进行统计分析。结果 前牙垂直压低的量及切牙牙冠长度明显减少（P＜0.01）,磨牙伸长量不显著。前牙的覆与覆盖均矫治达到正常范围。结论 微种植体做支抗压低上前牙、纠正深覆效果理想,能有效改善露龈笑。     

微种植钉高位植入内收压低前牙的疗效分析

目的探讨微型种植支抗高位植入上颌第二前磨牙与第一磨牙颊侧龈方内收压低前牙的临床疗效。方法选择10例上颌需强支抗的前突露龈笑正畸患者,植入微型种植体共20枚,植入1周后加载1.0¹.5 N力,观察种植体产生的牵引效果。结果所有病例矫治结束时均达到前牙有效内收压低,微笑露龈明显改善。结论正畸治疗中应用种植支抗高位植入牵引可有效内收压低前牙。     

应用微钛钉支抗矫治上颌前牙严重拥挤

目的研究应用微钛钉支抗治疗前牙严重拥挤畸形牙齿的治疗变化,介绍该治疗方法的临床要点。材料方法本研究包括8名正畸患者,年龄范围14.5—40.5岁,平均年龄25,7±7.7岁。8名患者的上牙列前牙区牙齿拥挤在Ⅱ度以上,拥挤平均在9.2毫米。粘结矫治器之前在上颌双侧第一磨牙和第二前磨牙之间或双侧第一、第二磨牙间的颊侧分别植入微钛钉种植体。治疗早期应用自攻型微钛钉进行尖牙向远中结扎,并在更换至稳定弓丝后利用微钛钉分期移动尖牙和侧切牙,牵引力值100克力。前牙排齐治疗前后拍摄头颅侧位片,并测量切牙和磨牙的治疗变化。结果 8名应用微钛钉支抗治疗上前牙拥挤组,牙列排齐后中切牙和第一磨牙在前后向和垂直向均未发生显著性移动。结论微钛钉支抗能够有效治疗严重牙列拥挤,可以避免前牙的往复运动,并达到磨牙强支抗的效果。     

微种植钉在正畸治疗双颌前突伴露龈笑中的应用

目的探讨微种植钉在治疗双颌前突伴露龈笑患者上的临床效果。 方法选取8例临床表现双颌前突伴露龈微笑的患者,在前牙区与后牙区植入微种植钉,并以其为支抗内收压低上切牙。治疗前后测量头颅定位侧位片与模型,t检验比较治疗前后测量值间的差异。 结果治疗前后上下切牙牙轴间差异有统计学意义（U1-SN：t = 11.993,P = 0.001;L1-MP：t = 6.439,P = 0.001）,上下切牙治疗前后的垂直向位置差异有统计学意义（U1/PP：t = 2.591,P = 0.018;L1/MP：t = 4.339,P = 0.002）。软组织测量值及牙龈暴露量呈明显改善（GSL：t = 3.198,P = 0.008）。 结论在治疗双颌前突伴露龈微笑患者时,可选择在前牙区与后牙区植入微种植钉,有助于在内收前牙的同时改善露龈笑。     

A re-evaluation of the distribution of the elastic meshwork within the periodontal ligament of the mouse

The elastic properties of the periodontal ligament have been attributed, in part, to oxytalan fibers, as no other types of elastic fibers are described there. It has been difficult to study the periodontal elastic meshwork by standard microscopic techniques because it is partially obscured by the adjacent periodontal ligament collagen fibers. Our study employed methods which either completely or partially removed mandibular molar periodontal ligament collagen fibers, exposing a previously undescribed periodontal elastic meshwork. The periodontal elastic meshwork was composed of many elastin lamellae containing both peripheral microfibrils of regular arrangement and central microfibrils of irregular arrangement, which could only be demonstrated in oxidized tissues. Peripheral, regularly arranged bundles of microfibrils resembled oxytalan fibers, which were often adherent to the border of the elastin lamella. Elastin lamellae containing irregular microfibrils resembled elaunin fibers. These fibers probably enclosed either blood vessels, nerves or collagen fiber bundles. Peripheral microfibrils attached elaunin to cementum, alveolar bone, blood vessels, and principal periodontal collagen fibers. Thus, the periodontal elastic meshwork is composed of both oxytalan and elaunin fibers. Microfibrils attach elaunin fibers to the adjacent non-elastic tissue and also form bundles which traverse the periodontal ligament space and are probably the oxytalan fibers demonstrable by light microscopic techniques. This meshwork of oxytalan and elaunin fibers probably contributes to tooth support and maintenance of periodontal homeostasis by dissipating chewing forces and maintaining patency of periodontal blood vessels.     

秦始皇帝陵区出土人第三磨牙的萌出情况

目的：调查秦始皇帝陵区山任陶窑遗址中人体颌骨第三磨牙的萌出情况。方法：选用秦代人体颌骨98副，观察萌出特点，计算阻生率，分析阻生情况。结果：通过对98副标本的观察，发现秦代人同现代人类一样可发生第三磨牙的多种萌出状况，其中包括先天缺失、畸形牙、阻生、正常萌出等。结论：秦始皇帝陵区山任陶窑遗址中人体颌骨具有同现代人类一样的第三磨牙萌出特点。     

螺圈对垂直曲力学行为的影响

目的 研究不同位置的螺圈及预成角度对垂直曲力学行为的影响。方法 利用大型有限元软件 ANSYS进行模拟计算。结果 螺圈的加入对垂直曲的M/F值的变化较明显。结论 对预成螺圈曲进行合理的形状设计,可以达到满意的效果。     

主观判听在腭咽闭合功能诊断中的应用价值

目的通过比较主观判听与客观检查诊断腭咽闭合功能的一致性,阐明主观判听在腭咽闭合诊断上的临床应用状况。方法对2000-2010年在四川大学华西口腔医院唇腭裂外科就诊的254例腭裂患者的语音资料进行回顾性分析。统计其主观判听结果和鼻咽纤维镜检查结果,计算二者的诊断一致率。应用Kappa检验和相关分析统计主客观评估的一致性和相关性。应用相关分析统计主观评估影响因素的相关系数。结果在254例腭裂患者中,主、客观评估一致的腭咽闭合完全（VPC）与腭咽闭合不全（VPI）病例数分别为58、167例,诊断一致率为88.58%,其中VPC诊断一致率为66.67%。Kappa值为0.721,R=0.751,P＜0.05,主、客观评估具有高度的一致性和相关性。高鼻音和鼻漏气与主观判听结果的相关系数R分别为0.697、0.590,P＜0.05,二者具有明显的相关性。结论主观判听诊断为VPC,以及主观判听为中重度高鼻音及鼻漏气的VPI患者可以免作客观检查;主观判听为轻度鼻漏气和高鼻音的患者需要结合客观检查,进一步明确腭咽闭合的诊断。     

The variability of the curvature of the labial surface of the upper anterior teeth along the facial axis of the clinical crown

OBJECTIVE: To mathematically assess the curvature of upper anterior teeth along the facial axis of the clinical crown (FACC) line to provide information valuable for assessment of enamel growth. METHODS: Forty upper study models were chosen from the Orthodontic clinic at the Charles Clifford Dental Hospital, Sheffield, UK. The study model incisors and canines were sectioned longitudinally down the FACC line, using a Microslice II cutting machine. Images were captured that showed the proximal view of the tooth curvature from incisal edge/cusp tip to the gingival margin. The images were converted into silhouettes and saved as bitmap files. These were vectorised and converted to an outline of xy data points. The forty xy files were mathematically adjusted so the distance between incisal edge and gingival margin were of equal length. Non Rotational Principal Component Analysis (PCA) was then applied at 20 equal intervals along the curve of each xy file to describe the shape of the teeth. RESULTS: Intra class correlation coefficient for intra-operator repeatability ranged from 0.821-0.998 showing good or excellent levels of reliability. PCA showed variation between tooth types. CONCLUSIONS: The method proved reliable. All tooth types showed that the mid-point region had the greatest rise variable, indicating that the most-prominent point was central or incisal for central and lateral incisors. All were skewed towards the incisal end and had kurtosis at both ends. Central incisors showed least variability. Greater variability was seen within the incisal third than within the gingival third for all tooth types.