牙科治疗器械所致噪声的初步研究

目的：研究不同测量距离下常规牙科治疗时器械所致噪声的强度及变化趋势。方法：在测量距离分别为1cm、10cm、20cm、30cm时测定牙科高速涡轮手机、慢速手机、超声洁治器械在空转和工作状态下所产生的噪声强度,并进行统计学分析。结果：几种器械在20cm以外距离工作所产生的噪声均在80dB（A）以下。在Icm距离上慢速手机磨削普通金属所产生噪声为89．53±1．25dB（A）,高速涡轮机头为95．67±0．65dB（A）,超声器械为104．90±1．25dB（A）。10cm距离水平高速涡轮机头和超声器械所产生噪声分别为85．25±0．47和86．68±0．84dB（A）。结论：距离手机20cm以上时,常规牙科治疗所产生的噪声对医师的听力无明显影响。但对患者的影响需引起注意。     

牙科技工所噪音状况调查与分析

目的：牙科技工在工作时暴露于噪音环境中,本研究对牙科技工用手机及各种设备所产生的噪音进行了调查分析。方法：采用精密声级计对2种牙科技工用手机（Kavo K9,NSK Vmax）在空转及不同工作状态下所产生的噪音进行检测,测定距离为离手机15cm、30cm、45cm;同时测定牙科技工设备在工作时所产生的噪音,测定位置为技工耳旁及离声源1.5m处。结果：2种牙科技工用手机在不同工作状态及不同测定距离时所产生的噪音在61～83dB之间。牙科技工设备所产生的噪音更高。如高速金属切割机、蒸汽清洁机、石膏风镐机产生的噪音都超过90dB。技工室内工作环境的噪音范围在65～83dB。结论：牙科技工所中产生的噪音对听力损害存在潜在危险,应对牙科技工进行定期的听力检查,并要求牙科技工在工作时佩戴耳塞等听力保护装置。     

牙科手机两种消毒方法效果的细菌学评价

牙科手机两种消毒方法效果的细菌学评价吴友农雷晓青杨聚才许多疾病可通过口腔中的唾液和血液传播，故牙科器械的消毒工作就显得十分重要。牙科手机（高速涡轮手机）在牙体病科最常用。由于构造精密，一些有破坏作用的消毒方法不能采用，又由于其价格昂贵，不可能成为一次...     

高速手机水道污染情况的监测与预防

目的 :检测牙科高速手机水道污染情况 ,为院内感染控制提供参考。方法 :对 2孔手机 (NSK )、4孔手机 (BlackPearl)于治疗后即刻、治疗后空转 3 0s、空转 60s后于手机管道接头处各留取水样 2 0份 ,并在管道水阀处留取基准水样 3份 ,分别进行细菌培养及HBsAg检测。结果 :2孔手机和 4孔手机治疗后即刻培养菌落数 ,分别为5 61cfu/cm3 ,3 69cfu/cm3 ,空转 3 0s后分别为 40 6cfu/cm3 ,15 6cfu/cm3 ,空转 60s后分别为 10cfu/cm3 和 <10cfu/cm3 ,基准水样均 <10cfu/cm3 。HBsAg阳性检出率 ,2孔手机治疗后即刻检出 3例 ,空转 3 0s检出 2例 ,空转 60s未检出。 4孔手机治疗后即刻检出 3例 ,空转 3 0s检出 1例 ,空转 60s后未检出。结论 :4孔手机在预防水道污染方面较 2孔手机优越。手机于治疗后空转 60s可大大降低瞬间负压回吸造成的水道污染 ,故提倡临床应用 4孔手机 ,手机于治疗后应空转 60s。     

空气喷磨技术在牙科中的应用

牙科临床使用的空气喷磨机是近几年发展完善的。它以压缩空气驱动细微的α-氧化铝颗粒形成高速粒子流进行工作,可用于临床去龋、粘接前的牙体预备及去除某些牙科修复体等,具有无痛、安全、省时等特点。本文就空气喷磨机的工作原理、性能特点及在牙科的应用范围、安全性等问题进行了综述。     

类金刚石膜在牙科车针表面的初步应用

目的:通过类金刚石镀膜(DLC)的方法提高牙科车针的耐磨性。方法:选择临床常用3种类型新车针,每种车针选择同种型号若干支,一组非镀膜作为对照组,一组镀膜作为试验组。对于金刚砂车针:由1名临床经验丰富的医生,使用镀膜与未镀膜车针,按照全冠牙体预备要求磨除离体牙(同一名正畸患者拔除的同名牙),同一根车针磨除5颗离体牙,记录操作者对车针切削能力的主观感受。对于树脂磨头:在相同转速、相同载荷下,对比镀膜与非镀膜磨头穿透树脂块效率。对于低速碳钢球形车针:对同名离体牙进行面Ⅰ类洞型的制备,每根使用3次之后,通过放大75倍的显微镜辅助观察工作端表面锋刃磨耗情况。结果:医生主观感觉镀膜金刚砂车针切削力好于非镀膜的车针。镀膜的树脂磨头穿透效率大于非镀膜树脂磨头。镀膜低速碳钢球形车针的磨耗程度低于非镀膜组车针。3组试验结果的差异均有统计学意义。结论:将DLC膜应用于牙科车针表面,特别是钨钢树脂磨头、低速碳钢球形车针表面,能明显改善切削效率,增加耐磨性,提高使用寿命。     

应用激光切割牙体硬组织的研究进展

目前，临床常规使用的高速手机和慢速手机在切割牙体硬组织时所产生的酸痛感、颌骨震动所引起的不适以及手机刺耳的噪音常使患者产生难以忍受的恐惧与疼痛。随着激光应用于临床的牙体制备开始受到口腔学者的日益关注，牙科激光技术的应用也正在逐渐受到重视和肯定。     

口腔科设备噪声声级的测量与分析

噪声是重要的职业病发病因素之一,它可造成听力的减弱或丧失.本文对我院常用的几种口腔器械的噪声进行了测量与分析.结果表明,震荡器在起动与震荡灌注模型时的噪声声级值没有明显差异,齿科技工磨机在空转与义齿抛光时的噪声声级值没有明显差异,而高、低速手机、超声波洁治器、切割机、石膏砂轮机在切割时噪声明显高于空转.其中切割机在使用时噪声最大高达97.82分贝.所测器械的平均声级范围为67.99～82.03分贝.     

口腔医院修复科医生噪声暴露水平的测量与分析

目的 通过测量诊室工作日及修复科医生日常常规操作产生的噪声,分析修复医生的噪声暴露水平。 方法 ①诊室工作日9点到10点,定点监测诊室噪声1 h;②单机情况下,测量修复医生进行7项常规操作时15、30、45 cm处的噪声。 结果 ①修复科诊室环境噪声为63.6~73.5 dB。②单机情况下,各操作距离增加噪声量降低,组间差异具有统计学意义。噪声强度对听力系统无危害。 结论 修复科医生的噪声暴露强度对听力系统没有潜在危害,但需关注噪声频率,神经系统和心血管系统的危害。医生工作过程中维持规范姿势有利于噪声保护。     

空气喷磨技术在牙科中的应用

牙科临床使用的空气喷磨机是近几年发展完善的，它以压缩空气驱动细微的α－氧化铝颗粒形成高速分子流进行工作，可用于临床去龋、粘接前的牙体预备及去除某些牙科修复体等，具有无痛。安全，省时等特点，本文就空气喷磨机的工作原理，性能特点及在牙科的应用范围，安全性等问题进行了综述。     

The performance of air-turbine handpieces in general dental practice

OBJECTIVE: To investigate variation in performance measures of fibre-optic, high-speed air-turbine handpieces during the course of daily use in general dental practice. MATERIALS AND METHODS: Four groups of five new high-speed fibre-optic handpieces were used in the routine treatment of patients over a period of 30 months by four general dental practitioners in two dental practices: Groups A, B: Super-Torque Lux 3 650B (KaVo, Biberach, Germany); Group C: BORA 898LE (BienAir SA, Bienne, Switzerland) and Group D: Toplight (W&H Dentalwerk, Burmoos, Austria). The dental practice teams had been rehearsed in the procedures to be followed before starting the study. Each dentist used the handpieces in strict rotation, while the groups were rotated monthly between practitioners. Four performance characteristics were measured before use, then at regular intervals: free-running speed (Hz) and bearing resistance (microNm) were measured using a purpose-built testing machine (Darvell-Dyson); illuminance (lux) and sound pressure level (dB(A)) were also measured. Handpieces were cleaned and lubricated in accordance with manufacturers' directions; all were autoclaved wet at 134 degrees C for three minutes. RESULTS: Free-running speed showed an initial increase after use for Groups A, B and C, which may be associated with a decrease in bearing resistance. All handpieces in Group C suffered bearing failure between months 21 and 23, preceded by a substantial increase in noise, while those in Group D suffered failure of the fibreoptic system between months 18 and 24. Other deterioration due to use was identified but Groups A, B and D were still in use at month 30. CONCLUSIONS: Variation in free-running speed, bearing resistance, illuminance and sound pressure level can be used effectively to monitor changes in air-turbine handpieces due to normal use. Although an increase in bearing resistance is associated with decreasing free-running speed, noise appears to be a useful indicator of imminent bearing failure. Assiduous adherence to manufacturers' directions for cleaning and lubrication may have contributed to increased bearing life.     

Studies on the performance of the dental air turbine handpieces. (Part 1). Air pressure and bur length to be influenced over the rotational performance of the air bearing type handpieces (author's transl)]

Air turbine handpieces are used as the dental cutting instruments for the clinical use and many appliances. But, there are no studies on the performance of air turbine handpieces. So, this paper shows the rotational performance of air turbine handpieces which are influenced over the supplying air pressure and cutting bur length. Experimentally used air turbine handpieces is air bearing type and it's set up air pressure to be supplied is 3.5 kg/cm2. So, in this experiments, the range of air pressure is 1.8 approximately 3.5 kg/cm2, which is established five stages. And the bur length of the rotational parts is 5 approximately 9 mm with five steps. As the results, the rotational performance of air handpieces are influenced over these factors of the air pressure and the bur length. And air pressure to be supplied are influenced to be not only over the rotational speed but the load for the putting a stop to the revolutions.     

5种灭菌器对牙科手机性能的影响

目的 了解5种灭菌器对牙科手机机械性能的影响情况。方法 用5种灭菌器分别对4把牙科手机进行灭菌200次，每完成10次灭菌全过程检测一遍牙科手机的夹持力和转速。结果 经200次灭菌后20支牙科手机中，1支停转，另有8支转速下降，低于30万转／分钟，但高于16万转／分钟．可满足基本使用要求。灭菌时间最短的灭菌器只明显影响一支牙科手机的转速，其他灭菌器均明显影响两支牙科手机的转速。结论 灭菌时间短对牙科手机机械性能影响小，灭菌前应做好牙科手机的清洁和润滑，以减少机械性能损耗。     

Dynamic measurement of the torque-speed characteristics of dental high speed air turbine handpieces*

The first requirement for adequate performance of an air turbine handpiece is sufficient power. Suppliers of such handpieces do not provide data on the power produced by their equipment. A method for determining the torque, speed and hence power during simulated operation is described. Forty-one new and used handpieces were tested. Maximum speeds up to 500 000 rpm, maximum torques up to 2.33 N.mm and maximum power up to 29.6 watt were observed. The maximum power was produced at between 49 and 79 per cent of the free-running speed. A relationship between maximum power and stall torque was noted. The maximum torque is at stall for ball-bearing units. The stall torque can be easily determined by a simple stall torque test which is described. Using this test, the performance of handpieces can be easily checked in the clinic. The one air-bearing handpiece tested performed in a manner similar to the others, except that stall occurred below 60 000 rpm.     

一次性口腔高速涡轮手机的研制

目的　研制一次性口腔高速涡轮手机。方法　通过分析使用一次性口腔高速手机对于防止医源性交叉感染的重要意义 ,指出目前口腔临床治疗中所使用的高速手机存在的主要问题。提出了一种创新性的一次性口腔高速涡轮手机的的设计和制造方案。结果　设计出符合人体工程学的一次性口腔高速涡轮手机 ,并对其进行空气动力学分析 ,同时制定出一次性口腔高速涡轮手机所应符合的 7项主要技术指标。结论　新研制的口腔高速涡轮手机性能达到了口腔临床使用的要求。     

Irrigation rates and handpieces used in prosthodontic and operative dentistry: Results of a survey of North American dental school teaching

PURPOSE: A data baseline on dental cutting methodologies was established by means of a survey of North American dental school teaching. MATERIALS AND METHODS: Sixty-four North American dental schools were surveyed regarding their recommendations on handpiece usage and coolant flow rates in fixed prosthodontics and operative dentistry. RESULTS: High-speed handpieces were the instruments of choice for tooth preparation in fixed prosthodontics. In operative procedures, recommendations for sole use of the high-speed, the low-speed, or both handpiece types were more uniform. CONCLUSIONS: North American dental schools advocate greater use of high-speed than low-speed handpieces. Although the use of high-speed handpieces predominate in schools in Canada and Puerto Rico, there is a proportionately higher use of low-speed handpieces than in US dental schools. Few (approximately 1 in 5) schools made recommendations on coolant flow rates during cutting procedures.     

A testing machine for dental air-turbine handpiece characteristics: free-running speed, stall torque, bearing resistance

The measurement of performance characteristics of dental air turbine handpieces is of interest with respect to product comparisons, standards specifications and monitoring of bearing longevity in clinical service. Previously, however, bulky and expensive laboratory equipment was required. A portable test machine is described for determining three key characteristics of dental air-turbine handpieces: free-running speed, stall torque and bearing resistance. It relies on a special circuit design for performing a hardware integration of a force signal with respect to rotational position, independent of the rate at which the turbine is allowed to turn during both stall torque and bearing resistance measurements. Free-running speed without the introduction of any imbalance can be readily monitored. From the essential linear relationship between torque and speed, dynamic torque and, hence, power, can then be calculated. In order for these measurements to be performed routinely with the necessary precision of location on the test stage, a detailed procedure for ensuring proper gripping of the handpiece is described. The machine may be used to verify performance claims, standard compliance checks should this be established as appropriate, monitor deterioration with time and usage in the clinical environment and for laboratory investigation of design development.     

Performance of high-speed dental handpieces subjected to simulated clinical use and sterilization.

BACKGROUND: The authors investigated the performance of nine commercially available high-speed air-turbine dental handpieces subjected to 1,000 simulated clinical uses and sterilizations. METHODS: Six new handpieces from each of nine different models were subjected to simulated clinical use with a custom-made handpiece wear tester and then autoclaved. Ten parameters related to clinical performance (longevity, power, turbine speed, fiberoptic transmission, eccentricity, noise, chuck performance, visibility angle, interocclusal clearance and water coolant spray pattern) were measured at baseline and after 250, 500, 750 and 1,000 use/sterilization cycles. RESULTS: Power, turbine speed, eccentricity and noise performance were statistically analyzed using one-way analysis of variance and Turkey post hoc pairwise comparison tests at the .05 significance level. At baseline, significant differences were found between models for all of these parameters. In general, from baseline to 1,000 cycles, the handpieces exhibited greater eccentricity and reduced fiberoptic performance. Longevity data analyzed by using Gehan's generalized Wilcoxon test for comparison of survival distributions (alpha = .05) revealed significant differences between the handpiece models. CONCLUSIONS: The results of this study indicate that no handpiece model is superior to the others in all parameters evaluated. All models evaluated can be expected to perform for at least 500 clinical use/sterilizations, or approximately one year, if properly maintained. CLINICAL IMPLICATIONS: Clinicians need to be able to identify handpieces that can withstand repeated heat sterilization without loss of performance or longevity. The results of this study will aid clinicians in selecting handpiece models that meet their needs.     

Development of new type plastics air turbine handpiece for dental use

The noise generated by the metal air turbine handpiece employed in dental practice is considerable and attended with predominant high frequency components. Therefore, investigation of the noise generation mechanism and development of a silent air turbine handpiece was only a matter of course. In addition, the metal air turbine hardpiece is comparatively heavy and its production cost is high. From this point of view as well, production of a light air turbine handpiece at low cost is also desirable. In order to overcome the objections to the metal air turbine handpiece, appropriate plastics materials were employed wherever possible. In this study, the number of revolutions, noise level, frequency analysis, start pressure and weight of newly produced plastics handpieces and metal handpieces were examined and compared. The following results were obtained: 1. The number of revolutions of single-nozzle type air turbine handpieces encased in plastics housings and fitted with metal turbine rotors was higher than that of all-metal air turbine handpieces. The noise level of the former tended to be lower. 2. The number of revolutions of multi-nozzle type air turbine handpieces encased in plastics housings and fitted with turbine rotors with plastics turbine blades was almost equal to that of similar metal handpieces, with the noise level tending to be lower. 3. In the case of handpieces fitted with turbine rotors with dynamic balance, the number of revolutions was high and the noise level was low. This indicated that dynamic balance was a factor affecting the number of revolutions and noise level. 4. Narrow band sound frequency analysis of single-nozzle type air turbine handpieces showed a sharp peak at the fundamental frequency which was the same as the number of revolutions multiplied by the number of rotor turbine blades. It is thought that the noise from air turbine handpieces was aerodynamic in origin, being generated by the periodical interruption of steady air flow by rotor turbine blades. 5. The start pressure of plastics handpieces was almost equal to that of metal handpieces. 6. The weight of plastics handpieces was 20%-50% of that of metal handpieces. The present results indicate that it is possible to produce a new type of light, silent and aesthetical air turbine handpiece.     

两种消毒方法对牙科手机灭菌效果的评价

目的 :比较含氯消毒剂浸泡法和环氧乙烷气体灭菌法对牙科手机的灭菌效果。方法 :利用枯草杆菌黑色变种芽孢和乙肝表面抗原阳性血清污染牙科手机 ,消毒后进行定量杀菌实验 ,用酶联免疫吸附实验 (ELISA)法检测HBsAg 结果 :牙科手机浸泡在有效氯含量为 30 0 0× 10 -6的消毒剂中 30分钟 ,细菌杀灭率及乙肝表面抗原的抗原灭活率均未达到 10 0 % ,而环氧乙烷灭菌法可达到 10 0 %。结论 :环氧乙烷灭菌牙科手机效果可靠。