双尖牙

目的：观察前牙、双尖牙慢性根尖周病变骨质破坏时，植入天然型无机骨（NNB）的修复与愈合效果。

Objective : To observe the restoration and healing effects of implantation of natural non organic bone ( NNB ) in chronic periapical bone destruction of anterior teeth or bicuspid teeth .

结果：健康成年人牙周附着水平平均值前牙区为5.03mm、双尖牙区为2.93mm、磨牙区为3.45mm。

Results : The average value of periodontal attachment level in the healthy adults was 5.03 mm in incisor zone , 2.93 mm in bicuspid zone , and 3.45 mm in molar zone .

方法：30颗离体单根管下颌双尖牙，用不锈钢K型锉，以标准法进行根管扩锉。随机分为3组，每组10颗牙，分别进行根管冲洗。

( Methods Thirty ) human teeth with single root-canal mandible premolar were instrumented using standard technique , then were divided into 3 groups , carrying on root-canal irrigation .

目的明确拔除4个第一双尖牙对Bolton指数的影响以及对咬合关系的影响。

Objective To investigate the effect of extraction of four first premolars on Bolton index and occlusion .

一副恒牙包括：8个尖牙，8个犬齿，2个磨牙和8个痰盂。（应为8个切牙incisors，4个尖牙canines，8个双尖牙premolars和12个磨牙molars）

A permanent set of teeth consists of eight canines , eight cuspids , two molars , and eight cuspidors .

方丝和圆丝摇椅弓均有使切牙压低双尖牙升高，打开咬合整平Spee曲线的趋势。

Both round wire and rectangular wire could intrude incisors , extrude premolars , level the curve of Spee and decrease the arch length .

方法选取43例拔除4个第一双尖牙和36例不拔牙治疗结果满意的病例，测量治疗后模型的牙齿宽度，计算比较其Bolton指数的差异；

Method The post treatment dental casts of 43 four first premolar extraction cases and 36 non extraction cases both with good occlusion were selected . Mesiodistal widths of mandibular and maxillary teeth were measured and Bolton index were calculated .

结果双尖牙减数治疗后MP-SN、PP-SN、MP-PP、Y轴角和S-Go/N-Me无显著性变化；

Results After treatment , the change of MP-SN , PP-SN , MP-PP , Y-axis and S-Go / N-Me was not significant in both groups .

上颌牙弓周径、上颌第一磨牙及第一双尖牙颊倾度有显著性增加（T1-T2），但有少量复发（T2-T3）。

The upper arch perimeter , the buccal inclination of upper first molars and first premolars were significantly increased ( T-T2 ) with some relapse ( T2-T3 ) .

结果推上颌第一恒磨牙平均后移3.9mm时上颌第二双尖牙在没有外力作用下随之向后漂移平均1.63mm。

Results After the maxillary molars were pushed distally ( average 3.9 mm ), the upper second bicuspids drifted backward without extra force ( average 1.63 mm ) .

下颌双尖牙和磨牙的有限单元法分析

The finite element analysis of the bicuspid and molar of mandible

固定阻萌器治疗87例早萌双尖牙的临床观察

Clinical Observation of Early Pairs of Canines Treated by Early Canine-Resistant Fixator

第二双尖牙先天缺失14例治疗体会

Treatment experience of 14 cases of congenitally missing second premolar

楔状缺状发病率最高的是第一双尖牙；

Most of wedge - shaped defects were found at first bicuspid teeth .

拔除第二双尖牙矫治牙列轻中度拥挤的疗效分析

Effect of extraction of second premolar in the treatment of dentia borderline crowding

未萌双尖牙和尖牙牙冠宽度的预测

Prediction of crown size of unerupted bicuspid and canine

缺损至龈下的双尖牙残根的两种修复方法比较研究

Comparison of the two methods of prosthodontics in subgingival residual root of premolar

上颌双尖牙保留率高于下颌双尖牙、上颌磨牙高于下颌磨牙。（？）共有10个无性系的净光合速率和蒸腾速率大于总体无性系平均值；

The average retention rate is The net photosynthetic rate ( Pn ) of E.

青岛地区青少年尖牙、双尖牙近远中宽度预测的研究

The Method of Predicting the Width of Unerupted Permanent Canines and Premolars for Qingdao Adolescent

上颌尖牙第一双尖牙易位的正畸治疗

Orthodontic treatment of maxillary canine-first premolar transposition

结果：部分标本的颏孔位于下颌第二双尖牙远中。

Result : The mental foramen of some specimen were be distal to the secondary premolar .

未萌尖牙和双尖牙总冠宽预测值表的建立

Establishment of orthodontic predictive charts for the sum crown widths of unerupted canine and two bicuspids

各组中，第一双尖牙、第一磨牙移动趋势基本一致。

The tendency of teeth movement of first premolar and first molar in four groups were similar .

双尖牙托槽脱落率明显高于前牙（P<0.05）；

The incidence of canines was higher than that of labial teeth ( P < 0.05 ) .

目的：应用有限元法建立上颌第一双尖牙冠根纵折模型。

Objective : Establishing a finite-element model ( FEM ) of the fracture tooth of first premolar .

高显著度。双尖牙周围牙槽骨应力最大值约为磨牙的2.1倍；

The stress of the bicuspid was about 2.1 times as high as that of the molar .

下牙弓变化中，第二双尖牙间和磨牙间宽度增加有显著性差异。

In addition , the changes of width between second bicuspid and mandibular molars showed statistical significances .

目的分析上颌第一双尖牙纵折粘结冠及桩核冠修复后牙体各部位的应力改变。

Objective To evaluate the change of the stress distribution of different treatment and compare with normal tooth .

尖牙区及双尖牙区前部是颊侧和舌侧相等；

In the canine and anterior portion of bicuspid regions , the buccal resorption is equal to the lingual ;

结果：模型一和模型二的最大应力均出现在第二双尖牙处，模型三最大应力出现在第一双尖牙处。

Among three experimental models , the magnitude and distribution of stress of the abutments were observed and contrasted .