锉牙

Eellike cyclostome having a tongue with horny teeth in a round ''.

似鳗的圆口纲脊椎动物，舌头上有锉牙，圆形''。

Any of various primitive elongated freshwater or anadromous fishes of the family Petromyzontidae, characteristically having a jawless sucking mouth with rasping teeth.

七鳃鳗，八目鳗一种七鳃鳗科的原始细长淡水或溯河产卵鱼，特点是长有无颌的吮吸嘴，嘴内有锉牙

Ss group was by prepared by k-files with step-back technique. all canals were obturated using lateral condensation technique.

将245颗具弯曲根管需行根管治疗的磨牙随机分为两组，he组用hero642镍钛锉及冠根向深入法预备根管，ss组用k锉及逐步后退技术预备根管。

Key words］root canal apex locator; periapical diseases; dental pulp cavity; working length; aged

1.2 方法常规开髓揭顶，清理根管，将root zx根管测量仪电极置于被测牙的对侧口角处，探测端接10号k型锉，缓慢进入根管，当测量仪显示到达根尖孔时，用制动片记录其长度，直接摄x线片证实k型锉所到达的位置，确定根管测量仪的准确性。

Group 4, reaming and filing instrumentation with reamers and H files; group 5, filing instrumentation with K files only; group 6, the ultrasonic instrumentation.

研究分两部分：第一部分：将60颗离体牙随机分为6组，分别为空白对照组、扩大针组、扩与K型锉组、扩与H型锉组、K型锉组和超声扩锉组，采用逐步后退法预备根管。

Abstract］objective: to observe the effects of different root canal file and the restoration of occlusal surface on the fracture resistance of premolars.

目的：观察不同根管锉预备根管及不同邪合面充填物对前磨牙牙体抗折强度的影响。

Methods: One hundred and twenty teeth with curved root canals were randomly divided into 2 groups: 74 curved root canals in group PT were prepared by ProTaper rotary Nickel-Titanium file with crown-down technique, and 75 curved root canals in group SS were prepared by K-files with step-back technique.

选择2005年6月至12月间本院口腔内科行根管治疗的120例患者（120颗牙），随机分为两组：试验组用ProTaper机用镍钛锉及冠根向预备技术预备弯曲根管74个，对照组用不锈钢K型锉及逐步后退法技术预备弯曲根管75个。

Methods: Fourty-five mandibular second premolars with single oval-shaped root canal were prepared with step-back technique and filled with warm vertical compaction technique. The teeth were divided into three groups randomly: ProTaper group, Mtwo group and manual stainless group. The operating time was recorded.

45颗具有椭圆形根管的下颌前磨牙经逐步后退法预备、热牙胶垂直加压充填后随机分为3组，分别用ProTaper再治疗器械和ProTaper器械，Mtwo再治疗器械和Mtwo器械，手用H锉和K锉去除牙胶。

Objective To evaluate clinical effect of the handling ProTaper Nickel-titanium rotary instruments in preparation of canals of posterior teeth.Methods 96teeth with pulpitis or periapical periodontitis were instrumented by handling ProTaper rotary instruments using step-down technique,and by K files using step-back technique for control.All teeth were obturated with lateral condensation methods.The efficiency of preparation was analyzed with ra-diographs before and after operation.

目的 评价手用ProTaper预备后牙根管的临床效果方法选取患有牙髓炎和根尖周炎的后牙96例，随机分成试验组和对照组各48例，试验组用手用ProTaper 锥度镍钛旋转器械逐步伸入法预备根管，对照组用K锉，逐步后退法预备根管，两组均用侧向加压充填法充填根管，根据治疗后的X线片，评价后牙根管预备效果。

Nickel-Titanium instruments have become widely used in the endodontic treatment. However, their unexpected separation was a serious concern in endodontics. To date, no scientific methods have been developed to evaluate the functional lifespan of Ni-Ti instruments. In this study, we used resonance frequency analysis to nondestructively detect the fatigue life of Ni-Ti instruments to determine the feasibility of this technique for use in the clinic.

镍钛合金根管锉已经广泛的使用在牙髓病的治疗上，但其无预警的断裂也是令牙医师关心的问题，之前并无一科学性的方法来评估镍钛合金根管锉的寿命，而本研究室利用自然频率的分析方式对镍钛合金根管锉做非破坏性的疲劳检测，确定此方式可行且在临床上有应用的价值。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。