自攻型微螺钉种植体支抗的临床应用研究

目的 研究自攻型微螺钉种植体作为磨牙强支抗的临床应用效果.方法 在30例采用自攻型微螺钉种植体作为磨牙支抗的临床病例中,选择6例已经结束治疗的患者进行分析.6例患者均为骨性Ⅱ类上颌前突患者,拔除上颌双侧第一前磨牙后采用上颌强支抗进行矫治.选择自攻型微螺钉种植体作为上颌支抗,以内收上颌前牙、关闭拔牙间隙.种植体植入部位为上颌第二前磨牙与第一磨牙牙根间的颊侧牙槽间隔,加力值为每侧1.47～1.96 N.对患者拔牙间隙关闭前后的头颅定位侧位片进行分析,测量前牙内收情况和磨牙支抗的变化.结果 6例患者共植入12枚微螺钉种植体,矫治后其上颌前突症状均得到明显改善,上颌切牙切缘平均内收6.06 mm,支抗磨牙平均前移0.44 mm,均获得了磨牙强支抗效果.治疗中,种植体保持稳定,种植体周围的软组织健康.结论 自攻型微螺钉种植体支抗是一种简便、有效的支抗形式,可以满足正畸临床治疗的需要.     

改良片段弓矫治技术远中移动上颌尖牙的临床应用研究

目的 探讨改良片段弓矫治技术联合横腭杆拉上颌尖牙向远中的临床效果和特点。 材料和方法 选择各类需要拔除上颌第一前磨牙或4颗第一前磨牙且需要强支抗的正畸患者24名,上颌放置横腭杆,用改良片段弓先拉上颌尖牙向远中移动,矫治前和移动6个月时拍摄头颅侧位定位片和取上、下颌模型,对测量结果进行统计分析。 结果 上颌尖牙到RL垂直距离减小约4.34㎜,上颌第一磨牙到SL垂直距离增大约1.19㎜,上颌尖牙后移和上颌磨牙前移距离之比为3.6:1;SN-MP角变化无明显差异。牙弓周长减小3.51㎜,上切牙拥挤度明显减轻。 结论 改良片段弓联合横腭杆能够高效远中整体移动上颌尖牙,避免了摩擦力的不利影响,且对SN-MP角无明显影响;支抗磨牙近中移动明显小于尖牙远中移动,有效的保护了支抗。     

腭中缝微种植钉联合铸造支架前移上磨牙的临床效果评价

目的: 研究微种植钉和铸造支架直接牵引上颌第二、第三磨牙前移关闭上颌第一磨牙缺隙的临床疗效。方法: 选择12例上颌第一磨牙缺失,且只接受局部正畸治疗的患者为研究对象。在腭中缝两侧植入微种植支抗钉2颗,制作铸造支架,稳定连接上颌同侧前磨牙和微种植钉。设计力线接近阻抗中心,颊舌侧加力牵引磨牙近中移动,关闭间隙。采用Graphpad Prism 6.0 软件包对所得数据进行配对t检验。结果: 所有间隙均顺利关闭,磨牙近中平均移动5.7 mm,磨牙轴倾度基本正常,牙周状况良好,其余牙保持原有咬合关系。结论: 利用微种植钉和铸造支架可以有效牵引上颌第二、第三磨牙近中移动,关闭上颌第一磨牙缺隙。     

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。     

微种植体支抗矫治上颌前突15例的X线头影测量研究

目的　评价微种植体在上颌前突患者正畸治疗中的支抗作用。方法　15例上颌前突患者,拔除上颌第一前磨牙后,使用微种植体支抗结合滑动法关闭拔牙间隙,对矫治前后的X线头颅定位侧位片进行测量,分析软硬组织的变化,采用SPSS 16.0软件包对数据进行统计学处理。结果　治疗后上颌中切牙切缘平均腭向移动6.52 mm,上颌第一磨牙近中接触点平均近中移动0.41 mm,上唇突点后移,鼻唇角加大,A点轻微后移,患者侧貌明显改善。结论　微种植体在关闭拔牙间隙过程中具有完全支抗作用。     

自攻型微钛钉种植体增强磨牙支抗的临床应用研究

目的　介绍自攻型微钛钉种植体用于正畸支抗的临床经验 ,评价该型种植体作为强支抗的有效性。方法　在 6 7例采用自攻型微钛钉种植体作为支抗的临床病例中 ,选择 5例II类骨型、上牙弓前突或双牙弓前突患者 ,矫治设计上颌均为减数双侧第一前磨牙 ,支抗设计为磨牙强支抗。内收前牙阶段的治疗应用自攻型微钛钉支抗种植体 ,种植体植入上颌第一恒磨牙与第二前磨牙颊侧根尖部之间的牙槽间隔 ,以每侧 15 0～ 2 0 0g力滑动法内收前牙。比较内收前后头颅X线侧位片 ,测量前牙内收情况和磨牙支抗的变化。结果　 5例牙弓突度均得到明显改善 ,切牙切缘平均内收 6 4mm ,支抗磨牙平均前移 0 3mm ,均获得磨牙强支抗的效果。治疗过程中种植体均保持了稳定 ,种植体周围软组织健康。结论　自攻微型钛钉种植体能作为稳定的骨性正畸支抗 ,代替口外力的使用 ,起到磨牙强支抗的效能。该型种植体具有操作简单灵活 ,可即刻加力 ,不依赖患者合作的优点     

比较2种部位种植钉支抗推上颌磨牙向远中移动的效果

目的：比较2种位置的微种植钉支抗推磨牙向远中的临床效果。方法：选择安氏Ⅱ类错25例,男7例,女18例,年龄15～29岁,平均22．58岁,牙列轻中度拥挤,面型较好,无明显前突。实验组（n ＝12）于颊侧第一磨牙近中颊根上方颧牙槽嵴处植入微螺钉种植体;对照组（n ＝13）于上颌第一磨牙与第二前磨牙牙根之间植入微螺钉种植体。推磨牙向远中,推力2．5 N。通过临床评价和对比2组矫治前后的头颅侧位定位片评价其治疗效果差异。结果：实验组和对照组微种植体首次植入成功率分别为100％（26/26）和87．5％（21/24）。治疗后上颌磨牙分别后移（2．91±0．96）mm 和（2．29±0．66）mm（P ＞0．05）。实验组磨牙压低的作用优于对照组,切牙唇倾的副作用小于对照组,切牙压入的作用优于对照组。结论：颧牙槽嵴处的微种植钉支抗推磨牙向远中移动较传统颊侧种植钉支抗对磨牙的垂直向压入及对抗切牙唇倾的效果好。     

微钛钉种植体支抗后移全牙弓16例临床分析

目的 研究微钛钉种植体作为支抗后移全牙弓矫治成人上颌Ⅱ度牙列拥挤的矫治效果。 方法 应用种植于磨牙颧牙槽嵴的微钛钉种植体整体向后移动全牙弓矫治16例上颌Ⅱ度牙列拥挤患者,以X线头影测量方法评价疗效。 结果 所有病例均获成功矫治,上颌第一磨牙平均远中移动2.93 mm、远中倾斜7.12°,第二前磨牙平均远中移动3.46 mm、远中倾斜11.09°,具有统计学意义(P＜0.05);上中切牙唇向倾斜度轻微增加2.12°、切缘平均前移0.66 mm,无统计学意义(P>0.05)。 结论 微钛钉种植体支抗是一种有效后移全牙弓矫治Ⅱ度牙列拥挤的方法。     

腭中缝微种植钉间接支抗压低上颌磨牙的临床研究

目的 评价应用腭中缝微种植钉间接支抗压低上颌磨牙的临床效果。方法 选择上颌磨牙伸长的患者30例,平均年龄37岁。腭中缝两侧2~3mm区各植入微种植支抗钉1枚,利用铸造支架在伸长牙颊舌侧各设计2个加力点,流体树脂将微种植支抗钉、铸造支架、伸长磨牙附件2个天然牙稳定连接形成新的绝对支抗源,橡皮链十字交叉加力压低,力值1.47~1.96N。分别测量治疗前后伸长磨牙近颊尖到腭平面、近中牙槽嵴顶到(牙合)平面以及近腭尖到根尖的距离,并记录牙周探针的深度,最后进行统计学分析。结果 30例患者磨牙均实现有效压低,压低值平均为3.4mm,治疗时间4~8个月,平均为6.5个月。治疗前后伸长牙牙周探诊深度、伸长磨牙近中牙槽嵴顶到磨面距离、近中颊尖到根尖长度的差异没有统计学意义(P>0.05)。治疗前后近颊尖到腭平面之间的距离差异具有统计学意义(P<0.01)。治疗中未发现患牙牙髓坏死以及种植钉松动脱落。结论 腭中缝微种植钉间接支抗可以有效压低伸长的上颌磨牙。     

微钛种植支抗钉用于改善患者露龈笑的临床研究

目的 探讨微钛种植支抗钉用于改善患者露龈笑的效果.方法 随机选取20例露龈笑患者(微笑时露龈高度大于3 mm),两侧上颌侧切牙和尖牙之间的根方植入微钛种植支抗钉,植入后即刻加力,在上颌侧切牙与尖牙间弓丝上加牵引钩,微钛种植支抗钉与牵引钩之间用弹性牵引固垂直牵引,每例以0.49 N力压低上前牙.观察患者露龈笑的改善程度和种植支抗钉的稳定性.结果 20例患者治疗前后微笑时露龈高度度平均减少3.06 mm.治疗中微钛钉种植体支抗的稳定率为80％.中切牙牙冠变短(0.75±0.68) mm,侧切牙牙冠变短(0.52 ±0.23) mm,尖牙牙冠变短(0.55土0.28)mm,治疗前后中切牙、侧切牙和尖牙的牙冠长度差异有统计学意义(P＜0.05).结论 微钛种植支抗钉可有效地改善露龈笑问题,值得临床推广使用.     

Macrodontia in association with a contrasting character microdontia

The dental, genetic, radiological and dermatoglyphic findings of a 19-year-old girl showing macrodontia of maxillary permanent central incisors in association with a contrasting character, microdontia of maxillary permanent lateral and mandibular primary central incisors and bilateral absence of maxillary first premolars and missing of the right mandibular second premolar and peg-shaped mandibular primary lateral incisors and canines were presented.     

Tooth anomalies associated with failure of eruption of first and second permanent molars

The occurrence of tooth anomalies in association with failure of the first and second molars to erupt was assessed in a sample of 1520 nonsyndromic subjects with uncrowded dental arches (mean age, 14 years 4 months) and compared with the prevalence rate calculated in a matched control group of 1000 subjects. The tooth anomalies examined included infraocclusion of deciduous molars, palatal displacement of maxillary canines, rotation of maxillary lateral incisors, aplasia of second premolars, and small size of maxillary lateral incisors. Associations among arrested eruption of first and second permanent molars and anomalies in tooth eruption and position (infraoccluded deciduous molars, palatally displaced canines, rotated maxillary lateral incisors) were highly significant (P <. 001). No significant association was found among the occurrence of molar eruption disturbances, aplasia of premolars, and small-sized laterals. These findings point to a common biologic cause for the appearance of failure of eruption of molar teeth and other disturbances in tooth eruption and position, most likely under genetic influence.     

Rapid canine distalization using distraction of the periodontal ligament: a preliminary clinical validation of the original technique

The process of rapid canine distalization through the distraction of the periodontal ligament is similar to the process in the midpalatal suture during rapid palatal expansion. Rapid canine distalization can be achieved in three weeks with this technique. The aim of this research was to evaluate the effects of rapid canine distalization on dentoalveolar tissues during the rapid distalization of canine teeth with semirigid, individual tooth-borne distractors. The study was carried out on 43 canine teeth in 18 (seven male and 11 female) patients who required first premolar extractions. The mean age of the patients was 16.7 years. The second premolars and first molars were used as anchor units. Orthodontic models, cephalometric and panoramic radiographs, and standard photographs of all the patients were taken before treatment and after the consolidation period. Periapical radiographies of the canines and anchor units were obtained once a week during the distalization period. The distractors were activated 0.25 mm three times a day, and the canines were distalized efficiently an average of three weeks. The within-group differences were evaluated with the Wilcoxon test. The maxillary canines were distalized an average of 5.76 mm with 11.47 degrees distal tipping. The maxillary first molars moved mesially 0.56 mm and extruded 0.64 mm. The maxillary incisors showed 1.44 degrees of palatal tipping. The mean distal movement of the mandibular canines was 3.5 mm with 7.16 degrees distal tipping. Anchorage loss was not observed in the mandibular first molars.     

Maxillary tooth transpositions: characteristic features and accompanying dental anomalies.

Transposition is a dental anomaly manifested by a positional interchange of 2 permanent teeth. The maxillary permanent canine usually transposes with the first premolar and occasionally with the lateral incisor. The records of 65 orthodontically treated individuals with maxillary tooth transpositions (40 females and 25 males) with an age range of 9 to 25 years (mean age, 13.4 years) were studied to determine the distribution of transposition and to evaluate the accompanying dental anomalies. Thirty-six individuals (55%) had a transposition of the maxillary canines and first premolars, 27 (42%) of the canines and lateral incisors, and 2 (3%) of the central and lateral incisors. Females had 60% more transpositions than did males. Substantially more transpositions were unilateral (88%), with a moderate left side dominance (58%). All dental anomalies associated with transposition--including missing lateral incisors and second premolars, undersized lateral incisors, retained deciduous canines, impaction of permanent canines and central incisors, and severely rotated adjacent teeth--were observed on the side of the transposition. This dominance of the affected side suggested that unknown local factors may play a major role in these dental anomalies.     

Sliding mechanics in extraction cases with a bidimensional approach

The Bidimensional technique is an edgewise technique in which 2 different sized vertically slotted brackets are used. On the central and lateral incisors, .018" x .022" brackets are placed on the central and lateral incisors and .022" x .028" brackets are placed on the canines, molars and premolars. The maxillary incisor brackets are programmed. All movements, including bodily retraction of the maxillary incisors are produced by sliding mechanincs. When retracting maxillary incisors, an .018" x. 022" wire which fills the vertical portion of the brackets, providing torque control, is inserted and 300 gm intra arch forces are placed for incisor retraction. In the buccal segments, the .018" x .022" wire is undersized relative to the canine, premolar and molar brackets and can readily slide through the brackets and tubes. The method is described and illustrated with one case report of the extraction treatment of a patient with Class I bimaxillary protrusion.     

Effectiveness of computer-assisted orthodontic treatment technology to achieve predicted outcomes

Objective:To evaluate the effectiveness of computer-assisted orthodontic treatment technology to produce the tooth position prescribed by the virtual treatment plan.Materials and Methods:Posttreatment models of 23 patients treated with SureSmile were digitally superimposed on their corresponding virtual treatment plan models utilizing best-fit surface-based registration. Individual tooth-position discrepancies between virtual treatment plan and actual outcome were computed. Discrepancies less than 0.5 mm in mesial-distal, facial-lingual, and vertical dimensions, and less than 2° for crown torque, tip, and rotation were considered clinically ideal. One-sided test of equivalence was performed on each discrepancy measurement, with P < .05 considered statistically significant.Results:Mesial-distal tooth position was clinically ideal for all teeth with the exception of maxillary lateral incisors and second molars. Facial-lingual tooth position was clinically ideal for all teeth except maxillary central incisors, premolars, and molars, and mandibular incisors and second molars. Vertical tooth position was clinically ideal for all teeth except mandibular second molars. For crown torque, tip, and rotation, discrepancy exceeded the limits considered clinically ideal for all teeth except for crown torque on mandibular second premolars and crown tip on mandibular second premolars and first molars.Conclusions:The effectiveness of computer-assisted orthodontic treatment technology to achieve predicted tooth position varies with tooth type and dimension of movement.     

Analysis of rapid maxillary molar distal movement without patient cooperation

The purpose of this investigation was to evaluate the treatment effects of an intraoral appliance used for rapid distal movement of the maxillary molars. The appliance studied, the Jones jig, is designed to deliver a distalizing force to the maxillary molar against an intraoral anchorage unit thereby eliminating the need for patient compliance. A retrospective study was performed comparing before and after lateral cephalometric radiographs on 13 patients who were treated for an average of 26 weeks with the Jones jig. The cephalometric radiographs were evaluated to determine if there were significant differences between pretreatment and posttreatment variables that included skeletal, dental and soft tissue relationships. Differences between the pretreatment and posttreatment means were significant for mesial angulation of the premolar anchorage unit (P < .001), distal movement of the maxillary molars (P < .01), mesial movement of the premolar anchorage unit (P < .01), mesial movement of the maxillary incisors (P < .001), and increased lower anterior facial height (P < .01). The anchorage loss, flared maxillary incisors, and increased facial height are negative treatment effects that should be expected when using this or similar appliance design. (Am J Orthod Dentofacial Orthop 1999;115:153-7)     

Skeletal Class III Malocclusion with Unilateral Congenitally Missing Maxillary Incisor Treated by Maxillary Protractor and Edgewise Appliances

This case report describes the orthodontic treatment of a 10-year-old female patient with a combination of Angle Class III malocclusion, a missing maxillary right lateral incisor, a supernumerary tooth with a short root on the lingual side of the maxillary incisor, a skeletal Class III jaw base relationship caused by a diminutive maxilla, and retroposition of the maxilla. We chose to close the space of the missing tooth, as well as the space created by extraction of the maxillary lateral incisor, by forward movement of the canine and premolars using a maxillary protractor with edgewise appliances. As a result, both the maxillary premolars and the molars were moved mesially, and a Class II molar relationship with tight interdigitation was achieved. Our results suggest that the combination of maxillary protractor and nontorque brackets was effective not only for correcting skeletal Class III malocclusion, but also for forward movement of the maxillary posterior teeth.     

Evaluation of the Jones jig appliance for distal molar movement.

The purpose of this study was to determine the effects of the Jones jig appliance on distal movement of maxillary molars and reciprocal effects on premolars and maxillary incisors. Cephalometric radiographs before and after orthodontic treatment of 72 consecutively treated patients, 46 females and 26 males, were measured to define treatment changes attributed to the Jones jig. Comparative measurements were made on a matched sample of 35 patients (20 females and 15 males) treated with cervical headgear by the same clinician. Both series of patients were treated to correct an Angle Class II molar relationship. The molar correction in the Jones jig patients consisted primarily of molar distal movement. Dental, soft tissue, and skeletal changes were evaluated and compared for significant differences between techniques. The results from the Jones jig sample showed the mean maxillary first molar distal movement was 2.51 mm, with distal tipping of 7.53 degrees. The mean reciprocal mesial movement of the maxillary premolar was 2.0 mm, with mesial tipping of 4.76 degrees. The maxillary first molar extruded 0.14 mm; the maxillary premolar extruded 1.88 mm. The maxillary second molars were also moved distally 2.02 mm and tipped distally 7.89 degrees. The longitudinal assessment (initial to completion of orthodontic treatment) showed significant differences between the Jones jig sample and the cervical headgear sample for lower lip to E-line and SNA. The Jones jig sample showed a mean decrease in lower lip to E-line of 0.25 mm versus 1.20 mm (P < .0212) for the headgear sample. SNA decreased 0.40 degrees for the Jones jig sample versus 1.20 degrees (P < .0093) for the headgear sample. However, the Jones jig sample and cervical headgear sample did not show significant differences of the final position in either linear or angular measurements of the maxillary first molars and corresponding premolar-incisor anchor units. The Jones jig appliance demonstrated treatment results comparable with those of the sample treated with cervical headgear. The Jones jig sample demonstrated effective distal molar movement and maintenance of the Class I molar relationship. Advantages of the Jones jig include minimal dependence on patient compliance, ease of fabrication, and ease of buccal force application.     

阻生前磨牙的临床研究现状

阻生牙是口腔中较常见的一种发育畸形,以尖牙、第三磨牙、中切牙、前磨牙及第二磨牙的阻生多见,尤以下颌第三磨牙及上颌尖牙阻生的患病率最高。目前国内外学者对阻生牙的研究主要集中在上颌尖牙和第三磨牙方面,对阻生前磨牙的研究甚少。临床上,很大一部分正畸患者需要进行拔牙矫治,且拔牙牙位主要位于前磨牙区,可见阻生前磨牙对正畸矫治设计及预后影响极大。本文对阻生前磨牙现有的研究状况进行综述,对阻生前磨牙的流行病学特点、临床定位和治疗方法进行总结,以期为正畸医生制定正畸矫治计划提供参考。