牙本质通透性与牙本质敏感症

牙本质敏感症是口腔临床常见疾病之一，其机制至今仍不十分清楚。液体动力学说认为全程牙本质小管开放，牙本质通透性增加，是影响牙本质敏感的至关重要因素。本文对牙本质通透性和牙本质敏感的关系进行综述。     

牙本质通透性与牙本质敏感症

牙本质敏感症是口腔临床常见疾病之一,其机制至今仍不十分清楚。液体动力学说认为全程牙本质小管开放,牙本质通透性增加,是影响牙本质敏感的至关重要因素。本文对牙本质通透性与牙本质敏感症的关系进行综述。     

定量研究碳酸氢钠和氟化钠混合液对牙本质小管的堵塞作用

目的：用激光荧光仪（KaVo DIALNOdent）定量研究碳酸氢钠和氟化钠混合液对牙本质小管的堵塞作用。方法：分别使用1mol/L碳酸氢钠液和0．12mol/L氟化钠液混合液、1mol/L碳酸氢钠液、0．12mol/L氟化钠液浸泡牙本质面，记录三组牙本质面激光荧光峰值，比较用药前后激光荧光峰值均数的变化。结果：三组用药前后激光荧光峰值均数的变化均有显著差异（P＜0．05），其中混合液组与另两溶液组比较，激光荧光峰值均数的变化有显著差异（P＜0．05），而两溶液组之间比较则无显著差异（P＞0．05）。结论：1mol/L碳酸氢钠液和0．12mol/L氟化钠液混合液，对牙本质小管有较好的堵塞作用。     

脉冲Nd：YAG激光照射对牙本质通透性的影响

本实验用不同能量参数的脉冲Ｎｄ：ＹＡＧ激光；分别照射牙本质窝洞底部，电镜观察和测定牙本质通透性，研究激光对牙本质的作用，初步探讨Ｎｄ：ＹＡＧ激光脱敏的机制。结果显示：０．６Ｗ（４０ｍＪ、１５Ｈｚ）组的牙本质通透性与对照组无统计学差异；０．９Ｗ（６０ｍＪ、１５Ｈｚ）和１．２Ｗ（８０ｍＪ，１５Ｈｚ）组的牙本质通透性明显增加。ＳＥＭ示所有激光组牙本质融熔、牙本质小管口模糊不清，洞底小管口部分被融熔物质阻塞。提示Ｎｄ：ＹＡＧ激光脱敏，可能存在其他的生物学脱敏机制。     

氟化钠与脉冲Nd:YAG激光联合应用对牙本质小管封闭作用的实验研究

目的 探讨氟化钠与脉冲Nd:YAG激光联合应用对牙本质小管封闭作用。方法 观察氟化钠、脉冲Nd:YAG激光及两者联合应用后,牙本质小管的形貌特征及变化。结果SEM下,联合应用组的大部分小管熔融封闭,而NaF处理组的牙本质小管开放。牙本质小管口的相对面积各组之间的差异均有显著性（P<0.05）。结论 氟化钠与激光联合应用具有良好的封闭牙本质小管的作用,优于单用激光组。其封闭效果能够耐受机械性刷洗的影响。     

碳酸氢钠和氟化钠混合液治疗牙本质过敏症的临床研究

目的：观察碳酸氢钠和氟化钠混合液治疗牙本质症过敏的疗效。方法：实验组使用1mol/L浓度的碳酸氢钠和0．12mol/L浓度的氟化钠混合液；对照组用0．48mol/L浓度的氟化钠溶液，记录第3次治疗后的疗效及实验组3个月后的随访结果。结果：实验组，显效54例（90．00％），有效4例（6．67％），无效2例（3．33％），总有效58例（96．67％）。对照组，显效24例（40．00％），有效33例（55．00％），无效3例（5．00％），总有效57例（95．00％）。两组总有效率无显著差异（P＞0．05），显效率有显著差异（P＜0．05）。3个月后实验组疗效；显效47例（88．68％），有效4例（7．55％），无效2例（3．77％），总有效51例（96．23％）。结论：1mol/L浓度的碳酸氢钠和0．12mol/L浓度的氟化钠混合液是一种高效、作用持久、使用安全的牙本质脱敏剂。     

微波治疗牙本质敏感症的疗效观察

牙本质敏感症是口腔常见病 ,面磨耗是引起后牙牙本质敏感症的主要原因之一 ,传统的治疗方法多用氟化钠甘油 ,麝香草酚或氨硝酸银脱敏。作者对后牙过度磨耗引起的牙本质敏感症行微波照射治疗 ,取得较好疗效 ,报告如下。材料和方法1 临床资料本组病例 43例 ,年龄 45～ 70岁 ,共 67个磨牙均为面磨耗致冷、热、酸、甜引起酸痛症状及咀嚼无力。诊断为牙本质敏感症。成都锦江微波电器厂生产的ＷＢ 10 0型 ,2 45 0ＭＨＺ多功能微波治疗机。2 方法将 67个患牙随机分为两组 ,对照组 3 3个牙采用硝酸银脱敏 ,实验组 3 4个牙采用微波照射。实验组 …     

脉冲Nd:YAG激光结合氟化钠对人牙本质、牙骨质人工龋的影响

目的 :探讨脉冲Nd :YAG激光结合氟化钠对离体人牙牙本质、牙骨质人工龋的影响。方法 :将 2 0个健康离体人牙分别制成 2 0个牙本质和牙骨质标本。偏光显微镜观察激光加氟化钠组、激光组、氟化钠组和空白组 (不处理 )人工致龋实验后 ,牙本质、牙骨质标本纵面人工龋形态 ,并测量龋损深度。结果 :1)人工龋形态 :在牙本质和牙骨质标本中 ,激光加氟化钠组表层致密 ,脱矿区比空白组、激光组和氟化钠组浅。 2 )人工龋深度 :在牙本质和牙骨质标本中 ,激光加氟化钠组龋损深度不仅小于空白组 (P <0 .0 0 1) ,也小于激光组 [P <0 .0 0 1(牙本质 )、P <0 .0 1(牙骨质 ) ],氟化钠组〔P <0 .0 1(牙本质 )、P <0 .0 5 (牙骨质 )〕。结论 :脉冲Nd :YAG激光结合氟化钠能有效阻止离体人牙牙本质、牙骨质人工龋的形成和发展 ,促进早期龋再矿化 ,因而具有抗龋性能。     

激光治疗牙本质敏感症的研究进展

牙本质敏感症作为一种口腔临床的常见病,其发病机制尚未完全清楚,目前较公认的是流体动力学说。脱敏治疗方法以封闭牙本质小管和降低牙髓神经敏感性为主,现阶段临床上仍无十分理想的脱敏手段。研究表明,激光治疗能弥补传统方法的不足,提高脱敏效果,特别是激光联合药物脱敏已成为近年牙本质敏感症治疗研究的焦点。文章对近年来国内外各种激光治疗牙本质敏感症的研究进展做一概述。     

2种方法联合治疗牙本质敏感症的临床研究

目的研究奥威尔脱敏糊剂和Nd:YAG激光以及它们联合作用在治疗牙本质敏感症中的作用。方法选择40例患者,共207颗患牙,分别进入空白组、奥威尔组、激光组、奥威尔+激光组联合组,每组10例患者。采用数字化疼痛评判法记录患者在治疗前、治疗后30 min、1周、6个月时的敏感程度。结果奥威尔组在治疗后30 min和1周时脱敏效果最明显,而激光组在治疗1周和6个月后效果明显。联合组在治疗后每个时间点效果均显著。空白对照组未发现明显改变。结论奥威尔和激光治疗均能对牙本质敏感症产生明显疗效。如果两者结合,效果会更好。     

Effect of desensitising toothpastes on dentinal tubule occlusion: A dentine permeability measurement and SEM in vitro study

Objectives

The purpose of this study was to evaluate the in vitro effectiveness of a new bioglass-containing and two commercial desensitising toothpastes on dentinal tubule occlusion after citric acid challenge or artificial saliva (AS) immersion.

Methods

One hundred dentin discs from human third molars were used. Specimens were randomly divided into five groups (n = 20), Group 1: EDTA-treated dentin; Group 2: brushing with distilled water; Group 3: brushing with Novamin; Group 4: brushing with Sensodyne Freshmint; Group 5: brushing with Colgate Sensitive. In each group, samples were then equally split into two subgroups (n = 10) to test two post-treatments: 6% citric acid challenge or 24 h immersion in artificial saliva. Dentine permeability of each specimen was measured before and after each treatment using a hydrostatic device working at 20 cm H₂O pressure. Data were analysed by two-way repeated measures ANOVA to determine if there were any significant differences within or between groups. Dentine morphology and surface deposits were observed by SEM.

Results

All three desensitising toothpastes significantly reduced dentine permeability and created precipitates on the treated dentine surfaces. Moreover, the reductions in dentine permeability showed partial recovery after a citric acid and artificial saliva immersion. Sensodyne showed significant resistant to acid attack and Novamin exhibited the lowest permeability after artificial saliva immersion for 24 h.

Conclusions

The application of the three toothpastes resulted in effective dentinal tubule occlusion. However, the new bioglass-containing toothpaste (Novamin) represented excellent occlusion effects after brushing treatment and AS immersion, while Sensodyne demonstrated more reduction in permeability when citric acid challenged.     

In vivo study on the effectiveness of a lacquer containing CaF2/NaF in treating dentine hypersensitivity

The purpose of this double-blind study was to evaluate the effectiveness of a commercially available fluoride lacquer (Bifluorid 12) containing CaF₂ (6%) and NaF (6%) in reducing dentine hypersensitivity. A fluoride lacquer containing only NaF (6%) served as a control. Twenty-five adult patients complaining about at least two hypersensitive teeth participated in this study. In each patient and at each appointment, one tooth was treated with Bi-fluorid 12, while the other was treated with the control substance. Sensitivity levels were determined before and after the application of each lacquer at baseline as well as at 1, 2 and 3 weeks after the start of study. The final evaluation of hypersensitivity was performed at 4 weeks, and follow-ups were undertaken at 6 and 12 months. A reproducible air blast stimulus and a visual analogue scale were used for evaluation. Results demonstrated a distinct reduction of hypersensitivity after 1, 2 and 3 weeks in the Bi-fluorid 12 group. Initially, no obvious effects could be observed in the control group. However, a clear alleviation could be observed after 2 and 3 weeks with the control. After 4 weeks, the overall sensitivity scores were comparably low, without any significant differences between the two fluoride lacquers. In both groups, the effects of treatment were seen over the 12-month observation period. Bifluorid 12 was considered at least comparable to the control. It is concluded from this study that Bifluorid 12 is effective in the initial reduction of dentine hypersensitivity. The combination of CaF₂/NaF can be recommended for clinical use.     

不同粒径和形貌的羟基磷灰石对牙本质小管的堵塞作用及耐磨性研究

目的 从定性和定量两方面研究不同粒径和形貌的羟基磷灰石(Hydroxyapatite,HA)对牙本质小管的堵塞作用及其耐磨性.方法 选择人前磨牙40颗,以高速手机制取牙本质片并抛光,酸蚀后随机均分为4组:20 nm HA组;30 nm HA组;12μm HA组;空白对照组(不使用任何实验品).各组分别用对应的材料刷洗牙本质片表面7d.将牙本质片一分为二,一半扫描电镜观察;另一半进行刷牙磨耗实验后扫描电镜观察,应用Image-Pro Plus 6.0图像分析软件计算牙体质小管堵塞率.结果 扫描电镜下见牙本质小管被颗粒状物堵塞,堵塞率达82%~96%,平均堵塞率为30 nm HA组(短棒状)>20 nm HA组(针状)>12μm HA组(球形).牙刷磨耗实验后,扫描电镜下见牙本质表面沉积层光滑致密,仍有63%以上的小管被封闭.结论 30 nm短棒状HA、20 nm针状HA及12μm球形HA对牙本质小管均具有良好的堵塞作用及耐磨性.     

A comparison between the occluding effects of the Nd:YAG laser and the desensitising agent sensodyne on permeation through exposed dentinal tubules of endodontically treated teeth: an in vitro study

OBJECTIVE: Dentine hypersensitivity may occur due to loss of covering enamel and/or loss of cementum after gingival recession, resulting in exposure of cervical dentine and patency of dentinal tubules. The effect of thermally cooled pulsed neodymium:yttrium-aluminium-garnet (Nd:YAG) laser on the permeability and structural appearance of the root canal wall was investigated in vitro. The aim of this study was to compare the occluding effect of Nd:YAG laser with that of sensodyne on exposed dentine. MATERIAL AND METHODS: Forty freshly extracted human maxillary anterior teeth were collected at random. Root canal obturations were performed using master apical file no. 60 k-type for obturated teeth. All teeth were stored in 100% humidity at 37 degrees C for 48h to allow time for the sealer to set. Dentine of 35 teeth was exposed by removing the cementum, and the remaining five teeth represented a negative control group. Specimens were examined using stereomicroscopy to show the surface topography of the dentine substrate before and after treatment with Nd:YAG laser or sensodyne. RESULTS: A double-blind technique was used when taking measurements of ink penetration (in mm) for each group. Teeth treated by Nd:YAG laser showed the least ink penetration, followed by teeth treated by sensodyne. The positive control group demonstrated complete ink penetration and the negative control group showed no ink penetration. Stereomicroscopic examination of specimens treated with Nd:YAG laser showed deposition on the dentinal surface, and specimens treated with sensodyne showed partial deposition. Untreated specimens were free of deposition and the tubules remained patent. CONCLUSION: There is no significant difference in the occluding effect of Nd:YAG laser and sensodyne toothpaste. Both treatments have a promising effect on the reduction of permeation through exposed dentinal tubules. However, the occluding effect of Nd:YAG laser occurs within seconds whereas that of sensodyne takes at least 3 weeks.     

The repeatability of human dentine permeability measurement in vitro

OBJECTIVE: The aim of this study was to determine the repeatability of apparatus designed to assess dentine permeability at two different pressures. METHOD: Forty-five human coronal tooth portions were prepared and permeability was measured at two separate time points, 5h apart, at 14 cm H2O pressure and then at 100 cm H2O pressure. Repeatability was determined using the limits of agreement (LOA) method. RESULTS: The results showed equal mean permeability of 0.6 microl at both time 1 and time 2 at 14 cm H2O pressure, and 2.7 and 2.5 microl at time 1 and time 2, respectively, at 100 cm H2O pressure. At 14 cm H2O pressure, the LOA were (-0.4, 0.4)microl and at 100 cm H2O pressure the LOA were (-0.2, 0.6)microl. CONCLUSION: Although repeatability measurement at 14 cm H2O pressure appeared to be acceptable, the higher permeability values at 100 cm H2O pressure may make the latter the pressure of choice despite the small bias.     

Treatment of dentinal hypersensitivity using a dentine bonding system

AIMS AND OBJECTIVES: Many agents have been used in treatment of dentinal hypersensitivity in the past, but dentine bonding systems have recently been suggested as being effective. This study examined the effectiveness of a dentine bonding system in the treatment of dentinal hypersensitivity in dental practice conditions. METHODS: Dentists in two dental practices agreed to carry out the project. One practice was in the UK, the other in India. A total of 34 patients who were diagnosed to have dentinal hypersensitivity were treated using the dentine bonding system. Patients were requested to record their perception of their pain on a 100mm linear scale, pre-treatment, one day and one week post-treatment. RESULTS: All patients experienced relief of pain, both 1 day and 1 week after treatment. Profile plots of the patients' perceived pain scores for the two practices separately indicated that there was a general trend across both practices for these to fall quite sharply one day after treatment and then generally level out one week post-treatment. There was evidence indicating a possible difference in pain perception in the two communities from which the patients were drawn. CONCLUSION: The dentine bonding system evaluated was successful in reducing the pain of dentinal hypersensitivity, at least in the short term.     

加热氟化钠对髓腔内温度变化影响的离体牙实验观察

目的:体外实验观察器械加热后放置于不同磨损牙面上所涂的氟化钠糊剂上不同时间髓腔内温度的变化。为临床使用加热氟化钠导入法治疗牙本质过敏症提供实验依据。方法:收集成人完整离体磨牙,根据SmithBGN对牙齿磨损分类,将牙合面制成轻、中、重度磨损,用加热不同时间的金属器械放置在不同磨损程度的牙面上不同时间,观察髓腔内温度变化,以所测温度最高值减测量前基础温度值,所得出髓腔温度上升绝对值进行比较分析。结果:加热器械5和10s,放置牙面不同时间,髓腔温度上升值不同,在最初10~20s内,髓腔温度随器械放置时间延长而上升。在相同时间内,磨损程度越重,髓腔温度上升值越高。结论:器械加热导入氟化钠过程中,器械温度一定时,器械放置时间和牙齿磨损程度是影响髓腔温度的主要因素。     

极固宁TM、Gluma与NaF治疗牙本质过敏症的临床疗效观察

目的:比较极固宁TM、Gluma、NaF等3种方法治疗牙本质过敏症的临床疗效.方法:选择2003年4月至2004年4月,在本院口腔科门诊就诊的牙本质过敏症患者60例,采用Chiss软件随机分组,三组病例分别采用极固宁TM、Gluma、NaF行牙本质过敏的脱敏治疗.结果:三种方法即刻有效率分别为74.4%、87.5%和94.8%,除极固宁TM组和NaF两组外,组间差异不明显(P＞0.05).治疗1个月和6个月后,极固宁TM组疗效显著优于Gluma组(P<0.01)和NaF组(P<0.01).治疗12个月,除极固宁TM组仍维持77.1%的有效率外,NaF组和Gluma组有效率分别下降到26.4%和43.6%,差异有显著性(P<0.01).结论:三种方法治疗牙本质过敏症均有较好的即刻疗效,但仅极固宁TM组远期疗效较好.