替牙晚期唇挡治疗的临床疗效分析

目的　观察替牙晚期唇挡治疗的牙牙合变化。方法　采用唇挡对2 0例替牙晚期间隙不调患者进行治疗,唇挡戴用6个月,通过治疗前后研究模型、X线头颅侧位片分析牙牙合变化。结果　上下牙弓前磨牙区牙弓宽度增加,上下切牙萌出、轻度倾斜,上磨牙远中倾斜、直立,下磨牙远中倾斜和移动。结论　替牙晚期唇挡治疗疗效肯定,可减轻或解除上下牙弓拥挤。     

唇挡对儿童牙弓及下颌骨生长发育的影响

目的研究下颌唇挡对替牙期及恒牙初期儿童下颌牙弓及下颌骨生长发育的影响,探索用下颌唇挡早期矫治下颌牙列拥挤的作用机理.方法选择替牙及恒牙初期下牙列拥挤患者30名(男14例、女16例),戴用下颌唇挡治疗6-10个月,进行治疗前后模型测量及X线头影测量分析.结果治疗后牙弓周长平均增加3.22mm,牙弓长度增加1.37mm,尖牙间宽度、第二双尖牙间宽度与第一磨牙间宽度分别增加1.63mm,2.35mm和1.83mm,切牙不齐指数减小1.66mm.表明切牙的唇移,牙弓宽度增大及第一磨牙远中直立对牙弓周长的影响较大.唇挡治疗后下颌平面角有所增加,但下颌骨位置与突度无明显改变.结论在儿童颌面部生长发育期间,下颌唇挡有助于增加下颌牙弓的长度与宽度,对治疗替牙期及恒牙初期下颌牙弓轻度或中度拥挤产生积极作用.     

唇挡对儿童面下部硬软组织侧貌影响的研究

目的　研究唇挡对替牙期及恒牙初期儿童面下部硬软组织侧貌形态的影响。方法　选择替牙期及恒牙初期下颌发育不良伴下牙列轻度或中度拥挤患儿 30例 (男 14例 ,女 16例 ) ,采用下颌唇挡治疗 6～ 10个月 ,进行治疗前后面部硬软组织X线头影测量分析。结果　唇挡治疗后下切牙唇倾 3.2 5°,呈以根尖为转动中心的倾斜移动 ,下颌第一磨牙远中倾斜 6 .13° ,呈以根分叉为转动中心的远中倾斜移动。下颌平面角增加 1.15° ,SNB角与面角无明显改变。颏唇沟厚度平均增加 1.2 3mm ,致使颏唇沟变浅 ,下唇角增大 (6 .0 5°) ,下唇及颏唇沟形态改善。结论　在儿童颌面部生长发育高峰期 ,唇挡可有效促进下颌牙弓生长发育 ,改善面下部硬软组织侧貌形态。     

唇挡对安氏Ⅱ类Ⅰ分类错(牙合)畸形患者下颌牙列及骨骼影响的临床研究

目的比较唇挡作用于下颌牙列前后的头颅侧位片及牙(牙合)模型,分析唇挡对下颌牙列及骨骼的影响.方法选择25例安氏Ⅱ类1分类错(牙合)患者,戴用唇挡时间1年,唇挡的位置位于距下前牙2mm,牙冠中点到牙龈缘4mm处,唇挡的远中插入下颌第一磨牙颊面管的圆管中,治疗开始之前以及1年后各拍头颅侧位片、下颌分析模型进行分析.结果由于前牙唇倾以及(牙合)向的抬高,使下颌牙弓长度明显增加,双侧尖牙、第一双尖牙、第二双尖牙以及第一恒磨牙之间的宽度明显增加.结论安氏Ⅱ类1分类错牙合伴有下前牙轻度拥挤的患者,在第一阶段非常适合使用下颌唇挡,不但可以加大牙弓的宽度,而且可以整平Spee's曲线以及打开咬合.     

多曲钢丝唇挡对替牙期和恒牙初期上颌牙弓的影响

目的 研究多曲钢丝唇挡矫治器对上颌牙弓的影响。方法 选择安氏Ⅱ类错(牙合),第二恒磨牙未萌出,前牙拥挤Ⅰ～Ⅱ°患者15例,采用多曲钢丝唇挡治疗并对其矫治前后X线头颅侧位定位片和模型进行测量分析。结果 上颌牙弓长度增加3.43mm。磨牙向远中移动,切牙唇向移动。牙齿移动主要为倾斜移动。上颌磨牙区、第一前磨牙区、尖牙区的牙弓宽度均增加,平均分别达5.87mm、2.71mm和1.92mm。结论 多曲钢丝唇挡是一种有助于解除轻中度牙列拥挤的口内装置之一。     

唇挡对安氏Ⅱ类Ⅰ分类错畸形患者下颌牙列及骨骼影响的临床研究

目的比较唇挡作用于下颌牙列前后的头颅侧位片及牙(牙合)模型,分析唇挡对下颌牙列及骨骼的影响.方法选择25例安氏Ⅱ类1分类错(牙合)患者,戴用唇挡时间1年,唇挡的位置位于距下前牙2mm,牙冠中点到牙龈缘4mm处,唇挡的远中插入下颌第一磨牙颊面管的圆管中,治疗开始之前以及1年后各拍头颅侧位片、下颌分析模型进行分析.结果由于前牙唇倾以及(牙合)向的抬高,使下颌牙弓长度明显增加,双侧尖牙、第一双尖牙、第二双尖牙以及第一恒磨牙之间的宽度明显增加.结论安氏Ⅱ类1分类错牙合伴有下前牙轻度拥挤的患者,在第一阶段非常适合使用下颌唇挡,不但可以加大牙弓的宽度,而且可以整平Spee's曲线以及打开咬合.     

唇挡对安氏Ⅱ类Ⅰ分类错畸形患者下颌牙列及骨骼影响的临床研究

目的　比较唇挡作用于下颌牙列前后的头颅侧位片及牙牙合模型 ,分析唇挡对下颌牙列及骨骼的影响。方法　选择 2 5例安氏Ⅱ类 1分类错牙合患者 ,戴用唇挡时间 1年 ,唇挡的位置位于距下前牙 2mm ,牙冠中点到牙龈缘 4mm处 ,唇挡的远中插入下颌第一磨牙颊面管的圆管中 ,治疗开始之前以及 1年后各拍头颅侧位片、下颌分析模型进行分析。结果　由于前牙唇倾以及牙合向的抬高 ,使下颌牙弓长度明显增加 ,双侧尖牙、第一双尖牙、第二双尖牙以及第一恒磨牙之间的宽度明显增加。结论　安氏Ⅱ类 1分类错牙合伴有下前牙轻度拥挤的患者 ,在第一阶段非常适合使用下颌唇挡 ,不但可以加大牙弓的宽度 ,而且可以整平Spee’s曲线以及打开咬合。     

上颌唇挡早期矫治引起的牙弓三维变化分析

目的 研究唇挡早期矫治上颌拥挤病例引起的牙弓三维改变.方法 选取正畸患者12例,平均年龄9.8岁.为缓解上颌的拥挤,戴用唇挡8个月.戴用唇挡前后取记存模型,进行三维数字化,以第三腭皱为参考将治疗前后的模型重叠,分析牙齿三维位置改变及倾斜度的变化.配对t检验比较治疗前后牙弓宽度和上牙弓弧形长度的差异.结果 戴用唇挡后,牙齿三维方向的改变以后部牙弓的变化最为显著,矢状向上颌第一前磨牙、第一磨牙分别远中移动2.08、2.03mm,上牙弓弧形长度增加5.12mm;垂直向上颌第一前磨牙升高1.17mm,第一磨牙升高0.72mm;横向上颌第一前磨牙间宽度增加2.62mm,第一磨牙间宽度增加3.08mm;以上各测量均有统计学意义(P＜0.05).同时上颌切牙存在少量前移、扩宽和唇倾.上颌切牙唇倾度增加3.90°,第一磨牙远中倾斜度增加8.23,有显著性差异(P＜0.05).结论 上颌唇挡可以缓解轻中度的牙弓拥挤.唇挡引起的牙弓长度增加主要是由于磨牙的远中移动、后倾以及牙弓的扩宽.     

唇挡对安氏Ⅱ类I分类错He畸形患者下颌牙列及骨骼影响的临床研究

目的 比较唇挡作用于下颌牙列前后的头颅侧位片及牙He模型，分析唇挡对下颌牙列及骨骼的影响。方法 选择25例安氏Ⅱ类I分类错He患者，戴用唇挡时间1年，唇挡的位置位于距下前牙2mm，牙冠中点到牙龈缘4mm处，唇挡的远中插入下颌第一磨牙颊面管的圆管中，治疗开始之前以及1年后各拍头颅侧位片、下颌分析模型进行分析。结果 由于前牙唇倾以及He向的抬高，使下颌牙弓长度明显增加，双侧尖牙、第一双尖牙、第二双尖牙以及第一恒磨牙之间的宽度明显增加。结论 安氏Ⅱ类1分类错He伴有下前牙轻度拥挤的患者，在第一阶段非常适合使用下颌唇挡，不但可以加大牙弓的宽度，而且可以整平spee’s曲线以及打开咬合。     

非拔牙矫治前后牙弓宽度改变的模型测量分析

目的 研究非拔牙矫治患者矫治前后牙弓宽度的改变.方法 选取牙弓轻度拥挤、采用非拔牙简单排齐的安氏I类错(牙合)患者77例,在模型上测量矫治前后尖牙间及磨牙间的牙弓宽度,并将测量结果进行配对t检验.结果 矫治后上颌尖牙间宽度增加(1.00 1.79)mm,下颌尖牙间宽度增加(0.51±1.66)mm,矫治前后上、下颌尖牙间宽度的改变有统计学意义(P＜0.05).矫治后上颌磨牙间宽度增加(0.23±1.36)mm,下颌磨牙间宽度增加(0.14±1.53)mm,矫治前后上、下颌磨牙间宽度改变无统计学意义(P＜0.05).结论 安氏I类非拔牙矫治患者矫治后上、下颌尖牙间宽度均有增加,而上、下颌磨牙间宽度相对稳定.     

Short-term treatment effects of quad-helix on maxillomandibular expansion in patients with maxillary incisor crowding

The purpose of this study was to evaluate the effects of the maxillary arch expansion on maxillomandibular arch widths in patients treated with the quad-helix versus untreated controls. The treatment group consisted of 50 consecutive patients treated for maxillary incisor crowding with a quad-helix appliance in the early mixed dentition. Lateral cephalograms and dental casts taken at the start (T0) and end (T1) of the quad-helix treatment were obtained. The control group consisted of 50 untreated patients with the same type of malocclusion. Two consecutive lateral cephalograms and dental casts of each untreated patient were taken at about the same time as T0 and T1. All these study materials were analyzed for comparison between the two groups. The mean ages at T0 and T1 in the two groups were about the same. The maxillary first molars moved and tipped distally in the treatment group and mesially in the control group. The quad-helix treatment actually expanded the mandibular and maxillary arches concurrently. The more the maxillary arch widths were expanded and the less the maxillary first molars were inclined distally, the more the mandibular arch widths were expanded. The quad-helix activation caused lingual tipping and mesiobuccal rotation of the maxillary first molars. The mesiobuccal rotation of the maxillary first molars could turn molar occlusal relationships for the better from Class II to Class I. The quad-helix treatment gives rise to spontaneous expansion of the mandibular arch concurrent with maxillary expansion in the early mixed dentition patients with maxillary incisor crowding.     

The effect of a maxillary lip bumper on tooth positions

The effect of the use of a lip bumper with anterior vestibular shields on the maxilla was studied in twenty-two 9-14-year-old children with a space deficiency in the maxillary dental arch. The lip bumper was used for 1 year. The effect of the treatment was evaluated from dental casts and profile cephalograms made before and after treatment. Both the width of the maxillary dental arch at the premolars and the length of the arch increased significantly by about 2 mm. The effect of the treatment on the antero-posterior position of the first molars was small. In one subject the molar was distalized 2.8 mm. The average effect was, however, a reduction in the anterior movement of the molar within the face by about 0.5 mm, i.e. the maxilla moved anteriorly 1 mm, but the molar only 0.4 mm. No skeletal effects were found when the group of subjects treated with a lip bumper was compared with a reference sample of untreated individuals. The main effects of a maxillary lip bumper thus seem to be a widening of the dental arch across the premolars, a moderate increase in arch length due to eruption and slight proclination of the incisors, and moderate distal tipping of the first molars.     

A comparison of the effects of 2 mandibular anchorage systems used with a 3-dimensional bimetric maxillary distalizing arch

The purpose of this study was to compare the effects of 2 mandibular anchorage systems used with a 3-dimensional bimetric maxillary distalizing arch. The Wilson rapid molar distalization appliance for Class II molar correction was used with 26 patients; two groups of 13 patients each were formed. In the first group (9 girls, 4 boys with a mean age 11 years 5 months), mandibular anchorage was gained by a modified lip bumper with a standard lingual arch of 0.9-mm stainless steel. The second group (7 girls, 6 boys, with a mean age of 13 years) had a 0.016 x 0.016-inch utility arch, with a 3-dimensional lingual arch for anchorage. Cephalometric radiographs were taken before and after maxillary first molar distalization. The treatment results showed that the extrusion of the mandibular first molar was statistically significant in both the modified lip bumper and utility arch groups (P < .01 and P <.05, respectively). The incisal edge of the mandibular incisor moved forward significantly in the modified lip bumper and utility arch groups (P < .05 and P < .01, respectively); however, the protrusion in the utility arch group was significantly greater than in the lip bumper group (P <.05). In both groups, significant proclination of the mandibular incisor was observed (P < .01). Comparison of the anchor units showed that there was significantly greater proclination in the utility arch group than in the modified lip bumper group (P < .05). Both anchor units similarly enhanced the mandibular first molar anchorage. However, particularly in the utility group, mandibular incisor anchorage control seemed to be inadequate.     

Effects of a three-dimensional bimetric maxillary distalizing arch

This study aimed to investigate the dental effects of a three-dimensional (3D) bimetric maxillary distalizing arch. The Wilson rapid molar distalization appliance for Class II molar correction was used in 14 patients (10 girls and four boys with a mean age of 12.18 years). The open coil springs were activated with bent Omega stops and Class II intermaxillary elastics. The mandibular anchorage was gained by a 0.016 x 0.016 utility arch with a 3D lingual arch or a lip bumper with a standard lingual arch. The lateral cephalograms taken before and after treatment formed the material of the research. A Wilcoxon test was used to statistically evaluate the treatment effects. The results showed that the distal tipping of the maxillary first and second molars, and first and second premolars and canines were statistically significant. Significant distal movement occurred in all posterior and canine teeth. The maxillary first molar distalization was found to be 3.5 mm. The maxillary incisor showed significant proclination and protrusion. The decrease in overbite was found to be statistically significant. The mandibular plane angle significantly increased by a mean of 0.5 mm. In addition, significant soft tissue changes were observed.     

Extraction treatment of a Class II division 2 malocclusion with mandibular posterior discrepancy and changes in stomatognathic function

This case report describes the successful extraction treatment of a Class II division 2 malocclusion with mandibular posterior discrepancy and a congenitally missing maxillary lateral incisor on the left side. The posterior space in the mandibular arch was small, and the mandibular second molars were impacted, with distal tipping. The discrepancies in the maxillary and mandibular arches were resolved by extraction of the maxillary lateral incisor on the right side and the mandibular second premolars on both sides. The mesial movement of the mandibular first molars occurred appropriately, with the second molars moving into an upright position. A lip bumper was used with a preadjusted edgewise appliance in the maxillary dentition to reinforce molar anchorage and labial movement of the retroclined incisors. Despite the extraction treatment, a deep bite could be corrected without aggravation as a result of the lip bumper and utility arch in the mandibular dentition. Thus, an Angle Class I molar relationship and an ideal overbite were achieved. The occlusal contact area and masticatory muscle activities during maximum clenching increased after treatment. The maximum closing velocity and the maximum gape during chewing increased, and the chewing pattern changed from the chopping to grinding type. The findings in the present case suggest that the correction of a deep bite might be effective for improving stomatognathic function.     

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。     

Dental crowding in primary dentition and its relationship to arch and crown dimensions among preschool children of Davangere

The purpose of the present study was to evaluate dental crowding in the deciduous dentition and its relationship to the crown and the arch dimensions among preschool children of Davangere. Stratified randomized selection of one hundred, 3-4 year old healthy children with all primary teeth erupted was done and divided into two groups. One group had children with anterior crowding in both the arches while the other had spacing. Alginate impressions of the upper and lower arches were made and the study casts were obtained. The tooth and arch dimensions were determined. Mesiodistal dimensions of all the teeth were significantly larger in the crowded arch group. However, the buccolingual dimensions of the maxillary right central incisor, mandibular lateral incisors and the maxillary molars and the crown shape ratio of maxillary lateral incisors, mandibular canines and mandibular right second molar was statistically different. No significant correlation was found between the arch width and the presence of crowding of deciduous dentition. The arch depth of the spaced dentition was greater when compared to the crowded ones. The arch perimeter of the crowded arches was significantly less than the spaced arches.     

Distal movement of mandibular molars in adult patients with the skeletal anchorage system.

The skeletal anchorage system (SAS) consists of titanium anchor plates and monocortical screws that are temporarily placed in either the maxilla or the mandible, or in both, as absolute orthodontic anchorage units. Distalization of the molars has been one of the most difficult biomechanical problems in traditional orthodontics, particularly in adults and in the mandible. However, it has now become possible to move molars distally with the SAS to correct anterior crossbites, maxillary dental protrusion, crowding, and dental asymmetries without having to extract premolars. This study evaluated the treatment and posttreatment changes during and after distalization of the mandibular molars. In 15 adult patients (12 women and 3 men), a total of 29 mandibular molars were successfully distalized with SAS. The amount of distalization and relapse and the type of tooth movement were analyzed with cephalometric radiographs and dental casts. The average amount of distalization of the mandibular first molars was 3.5 mm at the crown level and 1.8 mm at the root level. The average amount of relapse was 0.3 mm at both the crown and root apex levels. Of 29 mandibular molars, 9 were tipped back, and the others were translated distally in accordance with the established treatment goals. SAS is a viable modality to move mandibular molars for distally correcting anterior crossbites, malocclusions characterized by mandibular anterior crowding, and dental asymmetries.