A survey of the consent practices of specialist orthodontic practitioners in the North-West of England

OBJECTIVE: To use a questionnaire to obtain information on the consent practices of specialist orthodontic practitioners in the North-West of England and highlight any areas for improvement. DESIGN: Postal questionnaire. SETTING: This survey was conducted among specialist practitioners in 2005-2006. SUBJECT AND METHODS: A questionnaire was sent to 84 specialist practitioners on the specialist register in the North-West of England. This consisted of six sections with a mixture of yes/no responses and a section that determined for which subjects consent was obtained and how. OUTCOME: Responses were received from 58 (69%) practitioners. Ten were discounted. RESULTS: Forty-five (94%) of the 48 practitioners who responded routinely obtained consent from patients, and 27 (60%) used a consent form. Of these 27, 16 (59%) forms were based on a recommended design from an organization such as the British Orthodontic Society. Twenty-three (85%) practitioners gave the form to the patient/parent to read themselves, and 24 (89%) got the consent form signed by the patient/parent. Eighteen (67%) forms were countersigned by the orthodontist or an assigned member of staff. Seventeen (63%) practitioners gave the patient a photocopy. Of the 45 respondents who did obtain consent from their patients, seven (16%) practitioners assigned the consent process to a member of staff. Twenty-eight (62%) respondents would allow a patient under 16 to consent to treatment, with the youngest age being 10 years. CONCLUSIONS: Forty-five (94%) specialist practitioners who responded did routinely obtain consent from patients for treatment, but 18 (40%) did not use a consent form. The subjects discussed with the patient varied. Areas for improvement are highlighted.     

口腔正畸粘接剂的研究进展

口腔正畸治疗的成功,不仅取决于矫治的设计及医生的操作技巧,粘接剂的粘接性能也非常关键。良好的粘接是矫治顺利进行的保障,因此对粘接剂的性能提出了越来越高的要求。本文将对常见的口腔正畸粘接剂及其进展作一综述。     

A 2-year clinical study of two glass ionomer cements used in the atraumatic restorative treatment (ART) technique

The purpose of the study was to evaluate, in a clinical study over 2 years, the deterioration of two glass ionomer cements used with the atraumatic restorative treatment (ART) technique or approach. Fifty-five Fuji IX and 45 ChemFil Superior restorations were placed randomly in 23 adult patients, mainly in small occlusal preparations in molar teeth. The restorations were placed in a dental hospital by one dentist using the ART technique. Photographs, radiographs and replicas were obtained at baseline and subsequent recalls. Both cements were easy to mix and place, but the radiolucency of ChemFil Superior was a disadvantage. Both cements also showed early high losses of sealant and restorative material. After 2 years, 34.5% of the sealants appeared to be completely lost, with caries recorded in 5.3% of the exposed fissures. In some instances, these small lesions may have been present, but not detected clinically, at the time of sealing. Restoration failures of 7.0% were from wear and fracture of the cements and recurrent caries. Mean cumulative wear was 83.1 microm for Fuji IX and 104.0 microm for ChemFil Superior, which was not statistically significant. The cements became darker after their placement to more closely match the restored teeth, but there were few exact matches. There was no surface staining and only minor marginal discrepancies and staining associated with the restorations. Although the short-term clinical performance of the two glass ionomer cements was reasonable, the materials require further improvements in their mechanical properties, to reduce sealant losses and wear. The cements evaluated appear suitable for restricted use only, in posterior teeth.     

含氟玻璃离子水门汀预防正畸过程中釉质脱矿的临床研究

目的 观察含氟玻璃离子水门汀在预防固定矫治器矫治过程中釉质脱矿的作用。方法 选择需使用固定矫治器矫治并且试验牙齿无脱矿的患者40 例,正畸开始后于实验侧尖牙及双尖牙托槽周围1.5 mm 范围内涂布含氟玻璃离子水门汀(实验侧),对照侧不涂。约18 个月矫治结束时观察实验侧与对照侧各牙脱矿的变化,记录牙面的釉质脱矿程度,计算平均釉质脱矿指数(enamel decalcification index,EDI),对所获数据进行统计学分析。结果 矫治结束时,实验侧0 度、Ⅰ度、Ⅱ度、Ⅲ度脱矿牙齿颗数分别为60、16、3、1,对照侧为28、32、16、4,实验侧各脱矿程度均明显较对照侧轻(P<0.05)。实验侧的釉质脱矿率为25%,对照侧为65%, 实验侧明显低于对照侧 (P<0.05)。对照侧平均EDI 为0.238,实验侧为0.075,实验侧明显低于对照侧(P<0.05)。结论 含氟玻璃离子水门汀可以明显减轻正畸患者的釉质脱矿,降低平均EDI,在临床中可考虑用于预防正畸过程中的釉质脱矿。     

A survey of undergraduate orthodontic training and orthodontic practices by general dental practitioners

PURPOSE of the STUDY: To assess satisfaction with undergraduate orthodontic training, the variety of treatments undertaken in general practice, practitioners' perceived competence in orthodontics and the level of interest in continuing education in orthodontics. DESIGN: Cross-sectional questionnaire-based study. MATERIALS and METHODS: A questionnaire was mailed to 520 general practitioners in Dublin, Kildare and Wicklow as listed in Irish Dental Council Register of Dentists 2003. RESULTS: Forty-six percent of dentists responded. More than half (54 per cent) of the respondents were satisfied with both academic and clinical aspects of undergraduate training. Twenty-nine percent regularly perform orthodontic treatment. Only 60 percent feel comfortable treating orthodontic emergencies. Over 70 percent have either already attended or aspire to attend further training in orthodontic diagnosis and interceptive orthodontics. CONCLUSIONS: Our study indicates that in the greater Dublin area, graduates (those qualified less than 10 years) are increasingly satisfied with undergraduate teaching. Orthodontic treatment is performed regularly in general dental practice with interceptive procedures most often carried out. While ability to deal with orthodontic emergencies is not universal, practitioners do appear confident to perform a variety of orthodontic procedures. Interest in continuing education in orthodontics is very high. Our study indicates that participation in continuing education in orthodontics appears to translate into greater provision of orthodontic care in general practice.     

Evaluation of glass ionomer luting cements

Abstract – In the present study the three glass ionomer luting cements available on the Scandinavian market in June, 1982 were evaluated by comparison with a zinc phosphate and a zinc carboxylate cement. The following properties were tested: effective maximum grain size, retention, strength, bond strength to dentin, disintegration in and absorption of water and solubility in 0.001 n lactic acid. The glass ionomer cements proved to be fully acceptable luting materials.     

玻璃离子水门汀玻璃策粉表面特性与预处理的关系

目的 研究酸预在处理玻璃微粉对其表面特性的影响。方法 以醋酸水溶液处理玻璃微粉,利用粒子尺寸分子仪、比表面积分析仪、扫描电镜（SEM）和X射线光电子能谱（XPS）等技术手段,研究玻璃微粉表面特性与酸预处理的关系。结果 ①随着醋酸浓度增大或处理时间延长,玻璃微粉粒径和表面Ca^2 相对浓度减小、比表面积增大;②经5％醋酸预处理60min的玻璃微粉颗粒呈圆钝状,表面可见坑凹或孔洞。结论 酸预处理玻璃微粉导致其粒径、比表面积、表面Ca^2 相对浓度及形貌等表面特性的变化,进而会导致玻璃离子水门汀性能的改变。     

CGF—1型复合体的物理机械性能

目的：评价研制的新型光固化复合体ＣＧＦ－１与Ｄｙｒａｃｔ复合体、ＣＯ－１和ＦＵＪＩⅡ玻璃离子水门汀的物理机械性能。方法：按照有关实验方法分别测试研制复合体与对照材料的压缩强度、径向拉伸强度、挠曲强度、表面硬度。结果：ＣＧＦ－１的ＣＳ、ＤＴＳ、ＦＳ值都明显高于ＣＯ－１、ＦＵＪＩⅡ，接近Ｄｙｒａｃｔ。结论：ＣＧＦ－１型复合体的机械强度明显高于玻璃离子，可用作直接充填修复材料     

兰州地区青少年正畸患者正畸治疗意识的调查分析

目的 调查兰州地区青少年对错牙合畸形的认识及正畸治疗意识。方法 对兰州地区4个城区4 981名在校中学生进行错牙合畸形调查,并向其发放问卷了解治疗动机和正畸意识。结果 4 981名学生中错牙合患者3 168名（65.61%）,其中有452名正在矫治治疗（14.27%）。对2 716名尚未正畸治疗患者调查其未作治疗原因,有21.54%认为没有觉得不齐,20.00%的认为学习紧张。结论 兰州地区青少年错牙合患病率较高,矫治率低,对正畸治疗认识不足。     

The tensile strength of the union between various glass ionomer cements and various composite resins

Increasing use is being made of the glass ionomer cements as a lining for composite resin restorations, particularly when restoring posterior teeth. It has been suggested that it is possible to obtain a mechanical union between the two materials by etching the surface of the cement. This paper discusses the result of testing a broad variety of combinations of different glass ionomer cements and composite resins that have been reported on previously, and suggests that a number of factors need to be taken into account if the optimum physical properties are to be achieved from the union. There would appear to be four main factors which dictate the final strength of the union. The tensile strength of the cement itself is of primary importance and it seems the wettability of the resin bonding agent is also significant. When using some of the less heavily filled composite resins, the stresses set up by the setting contraction of the resin may be too great and, finally, the more heavily filled composite resins for restoration of posterior teeth often prove difficult to adapt to the underlying cement. With careful clinical handling, the so-called 'sandwich' technique is very useful. However, not all combinations of glass ionomer cement and composite resin will unite with sufficient strength to be successful clinically.     

正畸粘接用玻璃离子粘固剂防治托槽周围釉质脱矿的体外pH循环实验

目的　通过体外pH循环实验研究树脂改良型玻璃离子粘固剂 (resin modifiedglassionomercement)对托槽周围釉质脱矿的抑制作用。方法　选择 5对离体前磨牙 ,实验组用树脂改良型玻璃离子粘固剂粘接托槽 ,对照组用复合树脂粘接剂粘接托槽。全部样本每天进行pH循环实验 ,共60d。用偏振光显微镜观察托槽周围釉质脱矿病损并测量病损体部的深度、面积以及病损边缘与粘接材料边缘的距离。结果　对照组托槽周围釉质脱矿病损的深度和面积均大于实验组 ,配对t检验表明 2组间差异有非常显著性 (P <0 0 0 1 )。实验组病损均远离玻璃离子粘固剂边缘 ,而对照组病损均深入复合树脂粘接剂边缘的下方。结论　树脂改良型玻璃离子粘固剂是一种可以减少正畸治疗中釉质脱矿的粘接材料     

Demineralisation and remineralisation of dentine caries, and the role of glass-ionomer cements

In accordance with the principles of modern operative dentistry, to conserve tooth structure and to use therapeutic restorative materials, an understanding of the carious process in dentine and the biological properties of glass-ionomer cements (GICs) are necessary. Delineation of the outer necrotic from the inner vital and remineralisable carious dentine allows for the preservation of tooth structure. This delineation is not possible when relying on visual and tactile perceptions, but requires the use of a caries detecting dye. GICs are ideal dentine substitutes because of their anticariogenic properties, stable long-term ionic bonding, and ability to assist the process of remineralization. The range of usage of these restorative materials continues to expand with the development of improved products.     

Effectiveness of caries removal by the partial tunnel preparation method

The tunnel preparation method is designed to remove approximal caries through a channel from the occlusal surface while preserving the marginal ridge. This method entails reduced access to the caries lesion and thereby uncertainty as to the complete removal of caries. The purpose of the present investigation was to study the effectiveness of caries removal in 60 extracted premolars and molars by the partial tunnel preparation method. The glass polyalkenoat (ionomer) filling and the distance to the pulp were also examined. Examination of the sectioned teeth showed residual caries in the axial wall of two teeth and in dentin close to the enamel lesion in 10 teeth. Very few porosities were found within the glass polyalkenoat material and at the interface between the filling and the cavity walls.     

Early erosion of dental cements

The disintegration in water of various unset glass ionomer cements, a polycarboxylate and a zinc phosphate cement was measured gravimetrically after exposure of the cements to a constant water jet. The test gave reproducible results with significant variations between the various types and brands of cements. For zinc phosphate and polycarboxylate cements, no weight loss was observed in the period from 4 to 8 min after commencement of mixing. All the glass ionomer cements showed a significant loss of weight at 4 min and a somewhat reduced weight loss at 6 min after start of mixing. Two cements, a filling and a luting material, showed reduced weight when exposed to a water jet even 8 min after start of mixing. The early erosion as recorded in the present study conforms with the setting of the glass ionomer cements.     

The effect of etching on a number of glass ionomer cements

In view of the continuing interest in the use of glass ionomer cements as a dentine substitute or base under composite resins, further investigations were carried out on the effects of the length of time of etching of the surface of the cement prior to the placement of the resin. A number of cements are available on the Australian market which are advocated for use in this technique. Each of them was subjected to etching for periods of 15, 30, 45, or 60 seconds and then stored in water for one week. Examination under a dissecting microscope and a scanning electron microscope revealed some variation in results between the different cements. It would appear that not all those materials presently marketed for this purpose are entirely suitable. Whilst 15 seconds is the preferred time for most cements, some require times up to 60 seconds to achieve the best result. Also, some of the cements showed signs of cracking, expansion and distortion after they had been stored in water for one week to allow for maturation before being prepared for viewing under the SEM. It is suggested that this group of cements is not suitable for the 'sandwich' technique.     

Clinical comparison between a resin-reinforced self-cured glass ionomer cement and a composite resin for direct bonding of orthodontic brackets Part 1: wetting with water

The purpose of this study was to compare the clinical performance of a resin-reinforced self-cured glass ionomer cement to a standard composite resin in a split mouth design, by using both systems for direct bonding of orthodontic stainless steel brackets in every patient. Forty eight patients (34 females and 14 males, of which 29 were adults > 18 years of age) with fixed appliances were followed for a mean period of 10 months (range 4–16 months). The performance of 864 stainless steel brackets was evaluated: 404 brackets were bonded with GC Fuji Ortho glass ionomer cement (GC Industrial, Tokyo, Japan) onto teeth soaked with water, and 460 were bonded with System 1 + composite resin (Ormco, Glendora, CA). System 1 + recorded an overall failure rate (18.2%) significantly higher (p < 0.05) than GC Fuji Ortho (7.9%). There were no statistically significant differences (p> 0.05) between the failure rates in the upper and lower arches with either material. Both in the upper and lower arches, System 1 + exhibited a failure rate significantly higher (p < 0.05) than GC Fuji Ortho. When the bonding performance of the six anterior teeth was compared with first and second premolars, no statistically significant differences were found (p> 0.05) between bonding agents in either arch. System 1 + exhibited a failure rate significantly higher (p < 0.05) than GC Fuji Ortho, both in the anterior and posterior segments. Both bonding agents failed mainly at the enamel—adhesive interface, without causing any damage to the enamel.     

A comparative scalability study of different retrofitting materials

The purpose of this study was to compare the sealing ability of high-copper amalgam, glass ionomer cement, and silver glass ionomer cement as retrofitting materials when used with and without varnish. Seventy extracted human single-rooted anterior teeth were instrumented and the root canals obturated with laterally condensed gutta-percha and sealer. The apical 3 mm of each root was resected and a 2 mm-deep apical Class I preparation cut. The roots were then randomly allocated to six groups of 10 teeth and retrofitled with one of die experiment materials. Group I comprised high-copper amalgam; group 2, high-copper amalgam with cavity varnish; group 3, glass ionomer cement without varnish: group 4, glass ionomer cement with varnish; group 5, silver glass ionomer cement without varnish; and group 6, silver glass ionomer cement with varnish. Two groups of five roots each were used as positive and negative controls. The root surfaces were coated with nail polish and specimens immersed in 2% methylene blue solution for 14 days. After vertical sectioning, dye penetration was examined under a stereomicroscope. The results of the study were analysed statistically. The sealing ability of the conventional glass ionomer cement with varnish was significantly better while dye penetration was higher in silver glass ionomer cement without varnish group than the other groups (P > 0.01).     

The effect of dentine conditioning with polyacrylic acid on the clinical performance of glass ionomer cement — 3-year results

Forty cervical abrasion lesions were restored with a self-cure Type 2A glass ionomer cement. Prior to placement of the restorations, 20 lesions were scrubbed for 15 seconds with 25 per cent polyacrylic acid and 20 lesions were cleaned with a pumice and water slurry on a rubber cup. After three years, there was negligible marginal staining, and one restoration from each group was partly lost. There was no evidence to suggest that polyacrylic acid was preferred to pumice and water in the restoration of cervical abrasion lesions with glass ionomer cement.     

Genotoxicity and cytotoxicity induced by eluates from orthodontic glass ionomer cements in vitro

The aim of this study was to investigate genotoxicity and cytotoxicity of some orthodontic glass ionomer cements commercially available by means of the single cell gel (comet) assay. For this purpose, five commercial orthodontic glass ionomer cements (Vidrion C®, Meron®, Optiband®, Multicure® and Ultra Band Lok®) were tested in murine fibroblasts in vitro. For this purpose, eluates from each cement were prepared according manufactures instructions at 0, 2, 4, 8, 18, 32 and 64 days of immersion in artificial saliva at 37?°C. All orthodontic glass ionomer cements failed to induce cytotoxicity to murine fibroblasts for all periods evaluated in this study. However, Vidrion C® was able to induce genotoxicity after 64 days of exposure to eluates. Meron® also demonstrated genotoxicity as depicted by increasing DNA damage on 2nd day. Multicure® demonstrated genotoxicity on 32nd day and Ultra band Lok on 18th, 32nd days of exposure. Taken together, our results demonstrated that orthodontic cements derived from resin-modified glass ionomer composite (Multicure®) and compomer (Ultra Band Lok®) cause genetic damage in mammalian cells in vitro.