后牙病理性磨损树脂修复的临床效果探讨

目的:观察用直接树脂充填法和间接树脂充填法修复后牙病理性磨损的临床效果。方法:选择后牙牙合面有病理性磨损且具有充填空间的患者48例,患牙144颗,其中有牙本质过敏症状者38例98颗牙。患者按门诊顺序随机分为直接法修复组和间接法修复组2组各24例,在不备洞的情况下分别采用可乐丽菲露复合树脂直接或间接修复,比较治疗3个月及1年后树脂充填的临床效果、牙本质敏感情况和咀嚼效率改变情况。结果:治疗后3个月时复查,直接法和间接法两组患牙树脂充填体A级率无显著性差异(卡方检验,P>0.05);治疗1年后复查,间接法组患牙树脂充填体A级率优于直接法组,两组差异有统计学意义(卡方检验,P<0.05)。间接法组牙本质敏感治疗总有效率优于直接法组,两组差异有统计学意义(卡方检验,P<0.05)。治疗3个月及治疗1年后,间接法组的咀嚼效率高于直接法,两组差异有统计学意义(t检验,P<0.01)。结论:间接树脂法比直接树脂充填法修复后牙病理性磨损有较好的临床效果。     

牙齿磨损非接触式三维图象检测系统的研制和检测

目的研制并检测用于牙齿磨损测量的非接触式三维图象检测系统。方法通过数据轮量化手控移动平台使被测模型在水平方向移动,由线状光条和一个面阵CCD(Charge Coupled Device)摄像机获得单个牙齿咬合面3000～4000个点的三维坐标(在0.5mm移动步长条件下)。在Windows环境下完成图象采集、图象显示和相关测量。结果该系统测量范围为15mm×15mm×15mm,测量的精确度达到0.01mm,平均测量误差小于0.01mm,具有良好的操作稳定性。用本系统与万能工具显微镜对一组有微小高度变化的标准块进行测量,二者间差异无显著性(P<0.05)。结论该系统具有较高的精确度,其非接触方式、良好的稳定性、简单快捷的操作优于传统测量方法。     

Treatment of localized anterior tooth wear with a glass-fiber-reinforced composite resin: a clinical report

Developments in adhesive dentistry have provided the dental profession with new restorative materials and technology to restore esthetics and function to the worn anterior dentition. This clinical report describes treatment of localized anterior tooth wear with fiber-reinforced composite resin restorations as an alternative treatment method.     

The association of acidic reflux above the upper oesophageal sphincter with palatal tooth wear

This case-controlled clinical study, conducted at a secondary care unit, compared pH measurement at 2 cm above the upper oesophageal sphincter (UOS) in 31 patients complaining of extra-oesophageal symptoms of reflux to 7 control subjects. Twenty-four-hour ambulatory pH measurements were recorded and analysed at 5 cm above the lower oesophageal sphincter (LOS) and 2 cm above the UOS. In reflux patients the proportion of supine time when pH at 5 cm above the LOS was <4 was significantly greater than in controls. The proportion of time when pH at 2 cm above the UOS was <5.5 was also significantly greater in patients than in controls. Palatal tooth wear observed in the patient group correlated with acid reflux at night. In this group of patients presenting with symptoms of reflux, gastric acid passed through the upper oesophageal sphincter and increased the potential for erosion.     

Visual versus mechanical wear measurement of dental composite resin

SUMMARY This study compares a visual method for measuring composite wear with a relatively inexpensive mechanical technique. The visual measurements used a set of 17 graduated stone standards as the reference. Two sets of 10 unknown casts were evaluated. The first was a set of 10 stone replicas selected from the reference set in the range of 25–250 μm. The second set was composed of 10 casts of clinical restorations. The mechanical test employed a computer-controlled custom profilometer. Depth was recorded at 50 equidistant positions around the margin. A significant correlation was found (r > 0.98) between the visual and mechanical means for both measurement techniques. Mean values were equivalent for the standard casts. However, visual estimation of the clinical casts were significantly lower (61% of mechanical values) and thus not accurate for clinical use.     

An epidemiological scoring system for tooth wear and dental erosive wear

Background: The prevalence and severity of tooth wear and dental erosion is rising in children and there is no consensus about an index to be employed. Aim: To assess the reliability of an epidemiological scoring system dental wear index (DWI) to measure tooth wear and dental erosive wear. Design: An epidemiological cross‐sectional survey was conducted to evaluate and compare tooth wear and dental erosion using the dental wear index and erosion wear index (EWI). The study was conducted with randomised samples of 2,371 children aged between 4 years and 12 years selected from the State of São Paulo, Brazil. Records were used for calculating tooth wear and dental erosion; the incisal edge and canine cusp were excluded. Results: As the schoolchildren's ages increased the severity of primary tooth wear increased in canines (P = 0.0001, OR = 0.34) and molars (P = 0.0001, OR = 2.47) and erosion wear increased in incisal/occlusal (P = 0.0001, OR = 5.18) and molars (P = 0.0001, OR = 2.47). There was an increased prevalence of wear in the permanent teeth of older schoolchildren, particularly on the incisal/occlusal surfaces (P = 0.0001, OR = 7.03). Conclusion: The prevalence of tooth wear and dental erosion increased as age increased in children. The epidemiological scoring system Dental Wear Index is able to measure both tooth wear and dental erosive wear. This index should be used to monitor the progression of non‐carious lesions and to evaluate the levels of disease in the population.     

The development of a new index for measurement of incisal/occlusal tooth wear

A number of indices have been developed for the measurement of tooth surface loss but they have not achieved universal acceptance. The aim of this study was to develop a new index suitable for the monitoring of incisal/occlusal tooth wear on serial study models. The new index recorded incisal/cuspal wear for individual teeth. Each tooth was scored on a six-point scale ranging from 0-5. Six assessors evaluated the index and it was applied to baseline and sequential models taken after 20 years. The study demonstrated the value of maintaining long-term dental records in the form of study models for monitoring progressive tooth wear.     

Quantitative measurement of tooth and ceramic wear: in vivo study

PURPOSE: The aim of this study was to quantitatively measure tooth and ceramic wear over a 2-year period using a novel superimposition technique. Three ceramic systems--experimental hot-pressed ceramic (EC), Procera AllCeram (PA), and metal-ceramic--were used. MATERIALS AND METHODS: A total of 90 posterior crowns in 48 patients were randomized into 3 groups, and impressions were made at baseline and at 6-month intervals for 2 years. Clinical images were taken after using a dye to highlight surface changes. The impressions were digitized and modeled as superimposable 3-dimensional colored surface images. The depth of wear at the occlusal contact areas was quantitatively measured at 6, 12, 18, and 24 months. RESULTS: The quantitative evaluation showed more wear in Procera AllCeram at the occlusal contact areas, whereas the experimental and metal-ceramic systems showed less wear. There was a significant difference in the amount of enamel worn between all types of restorations (P < .05). There was a statistically significant difference (P < .05) in the mean depth of wear between all systems. CONCLUSIONS: The metal-ceramic and experimental systems showed less change, indicating improved wear resistance compared with Procera AllCeram. In addition, enamel opposing metal-ceramic and experimental crowns showed less wear compared to enamel opposed by Procera AIICeram crowns.     

牙齿病理性磨损充填治疗的临床效果研究

目的观察尚未出现牙髓症状的牙齿病理性磨损充填治疗的临床效果。方法选择牙列完整、后牙骀面有病理性磨损且具有充填空间的患者10例，患牙48颗，均无牙髓症状。使用后牙树脂充填后，比较治疗前、治疗后3个月和1年时，患者主观感觉和咀嚼功能（咬合力、咀嚼效率和咬肌肌电活动）的变化，观察树脂充填的临床效果（美国公共健康部评价系统）。结果患牙经充填治疗后患者临床症状消失，咬合力增加（P〈0．05），咀嚼效率明显提高（P〈0．01），治疗前后下颌息止位、大力咬合时、咀嚼运动时，颞肌前束和咬肌的活动强度、活动对称性及用力方式差异均无统计学意义（P〉0．05）；治疗后3个月和1年时复查，48颗后牙树脂充填体各项指标A级率为100％。结论对后牙骀面尚未出现牙髓症状的病理性磨损用树脂进行充填是一种有效的治疗方法，可以解除患者的临床症状，减缓磨损的发展，增加咀嚼效率及患牙咬合力。     

Accuracy and precision of a system for assessing severity of tooth wear

PURPOSE: The purpose of this study was to introduce a computer-assisted quantitative tooth wear-analyzing system and test its accuracy and precision. MATERIALS AND METHODS: An image of a horizontally projected dental arch was captured, and the facet area of each tooth was calculated using a digital image analyzer. For normalization, the facet area of the individual tooth was divided by the total area of the corresponding tooth; this result was the tooth wear score. The accuracy and precision of this method were determined through the intraclass correlation coefficient using 10 dental casts. Tooth wear on the dental casts of 50 subjects was actually measured. RESULTS: The accuracy of the tooth wear score determined by a newly trained examiner was greater than 0.85 of the intraclass correlation coefficient; this was tested against the score determined by consensus of three experienced examiners. The reproducibility within a 1-week interval was also greater than 0.85. With regard to the tooth wear score from 50 sets of dental casts, the distribution of tooth wear was generally consistent with data reported in the literature. CONCLUSION: The results suggest that the newly trained examiner can exhibit adequate accuracy and precision after appropriate training in identifying tooth wear facets. Recorded data from 50 subjects added face validity to this new system.     

Use of a tongue-pressure measurement system to assist fabrication of palatal augmentation prostheses

PURPOSE: The purpose of this study was to determine a baseline value of tongue pressure on the palatal region in normal subjects that could then be used to assist in fabrication of a palatal augmentation prosthesis (PAP). MATERIALS AND METHODS: A tongue-pressure measurement system with 36 rubber pressure sensors was constructed for this study. This system was applied to 16 normal subjects, and the tongue pressure on the palatal region was measured when they were swallowing. RESULTS: The maximum tongue pressures seen during swallowing were 85.0 g/cm2 in the early stage, 95.0 g/cm2 in the middle stage, and 93.0 g/cm2 in the late stage. The average maximum tongue pressure throughout swallowing was 91.0 g/cm2. The tongue pressure in the early stage ranged from 3.37 g/cm2 to 8.74 g/cm2. A significant difference was found between the anterior and the posterior regions and between the central and the posterior regions. The value in the middle stage ranged from 5.32 g/cm2 to 10.22 g/cm2. Significant differences were found between the anterior and the posterior regions and between the central and the posterior regions. Values in the late stage ranged from 6.80 g/cm2 to 7.91 g/cm2. CONCLUSION: The average maximum tongue pressure against the palate of approximately 90 g/cm2 suggests that a PAP sufficient for swallowing should be strong enough to withstand this amount of pressure. The device is also useful to check for variations in the tongue contact area during trial of the prosthesis.     

牙纵裂缝隙内三层封闭法临床疗效观察

目的观察纵折裂牙折裂缝隙3层封闭法的临床治疗效果. 方法纵折裂牙折裂缝隙3层封闭法是使用碘甘油、黄碘氧化锌糊剂、玻璃离子水门汀按顺序对纵折裂缝隙3层封闭.89颗纵折裂牙使用3层封闭法作为实验组行保存治疗,随访3年.同时对以前没有采用3层封闭法的122颗纵折裂牙治疗后随访3年的资料作为对照组比较.结果实验组与对照组在3年成功率的对比上有明显差异(P<0.01),实验组的成功率高达74.83%;对照组成功率21.13%.结论纵折裂牙折裂缝隙3层封闭法针对折裂缝隙的感染和封闭治疗有很大的现实意义,能明显提高纵折裂牙保存治疗的成功率.传统的纵折裂牙保存方法不很成熟.     

Effects of a self-etching resin coating system to prevent demineralization of root surfaces

OBJECTIVES: The purpose of this study was to evaluate the ability of an experimental self-etching resin coating system to protect against demineralization of the root surface in vitro, comparing its effectiveness with two commercial one-step self-etching adhesives. METHODS: The experimental resin coating system (EC), consisting of a self-etching primer and an acrylate-based resin, or the two commercial self-etching adhesives, Adper Prompt-L Pop (AD) and Clearfil Tri-S Bond (S3), was applied to the cementum of a human extracted tooth root. The specimens were immersed in acetate buffer at pH 5.5 for 4 weeks, and the degree of demineralization underneath the materials was evaluated by microscopic observation and contact microradiography. Each material's sealing and interfacial ultrastructure on the cementum was morphologically examined by scanning electron microscopy, and their bonding ability to cementum was determined by microtensile bond strength (MTBS) tests. RESULTS: Application of AD and S3 showed limited effects to protect against demineralization, but no demineralization was observed for EC. EC showed greater coating thickness than the other two materials, with formation of integral hybridized layers with cementum. Although the MTBS values for EC were significantly lower than those for AD and S3, cohesive failure in resins was the prevalent fracture mode for EC, showing no possible disadvantages in bonding ability. SIGNIFICANCE: The experimental resin coating system effectively prevented acid demineralization on root surfaces due to its ability to produce an appropriately thick coating and an integral hybridized layer.     

丙烯酸树脂牙与树脂及陶瓷材料相对磨耗的体外研究

目的：比较成品丙烯酸树脂牙与丙烯酸树脂、Targis及Artglass复合树脂、陶瓷材料的相对磨耗性,为临床选择修复材料提供依据。方法：制作成品丙烯酸树脂牙的牙尖形状标本40个,选择丙烯酸树脂、Targis及Artglass复合树脂、陶瓷4种材料进行相对磨耗实验,每种材料均制作块状标本10个。在自制磨耗装置上循环磨耗50000次后测试各种标本的高度丧失。结果：丙烯酸树脂牙牙尖磨耗度由大到小分别为：陶瓷、复合树脂、丙烯酸树脂。丙烯酸树脂、复合树脂、陶瓷的磨耗度由大到小分别为：陶瓷、丙烯酸树脂、复合树脂。结论：陶瓷与丙烯酸树脂牙相对磨耗时,树脂牙的磨损较大,临床上应避免使用将陶瓷与树脂作为相对磨耗材料,复合树脂是丙烯酸树脂牙较为理想的对颌修复材料。