镓银合金充填临床观察

本文系统追踪观察镓银合金充填后牙２０颗，对侧同名后牙同时充填ＧＫ高铜银汞合金５颗，观察６个月．发现两种充填物的物理、机械性能无差别，均无明显牙髓刺激症状，镓银合金充填术前后牙髓活力电测试参数无明显差别，镓银合金无致敏性．提示临床可应用镓银合金替代银汞合金，特别是用于后牙充填     

牙科充填材料镓合金

银汞合金作为充填材料，由于其操作简单，机械强度大等优点，至今仍在口腔治疗中占主要地位。但其对环境污染及对人体毒害作用一直未得到有效解决，近几年来，一种瓣型金属充填材料－镓合金已经研制出来，并已通过一系列动物，毒性检测，目前正逐步被推荐至临床应用，该文主要对近几年来有关镓合金充填材料的理化特性，临床应用及临床操作要点等方面的研究情况进行综合报道。     

磨牙根尖切除术和倒充填术的临床疗效观察

目的观察根尖切除术和倒充填术在难治性磨牙牙髓病和根尖周病治疗中的临床疗效。方法选择41颗难治性牙髓病和根尖周病的磨牙,经常规根管治疗无效,进行根尖切除术和根尖倒充填术,术后随诊观察。结果本组41颗患牙,其中28颗手术治疗后无自觉症状且完全恢复功能,组织附着紧密。10颗患牙经治疗后咀嚼基本正常,瘘管消失,疼痛消失,根尖阴影缩小。临床成功率为92.68。结论根尖切除术和倒充填术在难治性磨牙牙髓病和根尖周病治疗中,具有满意的疗效。     

镓合金的性能及其临床应用前景

银汞合金用作齿科充填材料已有一百六十余年之久.近期分散型银汞合金及高铜银汞合金的开发,消除了引起边缘破损的γ_2相,加入了低共熔银-铜晶体和更高比例铜,进一步改善了其耐腐蚀性及机械性能,但因其含汞量接近50％,操作过程中汞蒸气的污染以及多余银汞合金如何适当处置已成难题。近来复合树脂在后牙修复中的临床应用逐年增加,但亦存在操作过程复杂:如需酸蚀和使用粘接剂,以及机械性能较弱:如低磨耗和易产生边缘折裂等缺点而无法取代银汞合金。 鉴于此,一种新型充填合金-镓合金作为银汞合金的替代物,已引起关注。镓的熔点为29.78℃,制成液态合金后熔点约为10C左右,仅次于汞(- 38.78℃)。不同成分的镓合金如:Ga-Gu-Sn,Ga-Ag-Cu-Su,Ga-Au,Ga-Pd,Ga-Pd-Sn等已被研制并进行了多项性能评估。镓合金较之传统的银汞合金在机械性能、固化速度、与釉质的粘接性、边缘封闭和耐热性方面显示优势,同时也由于诸如操作困难、固化膨胀、低耐腐蚀性、牙髓刺激等问题在临床应用的推广上有待进一步探索。本文对镓合性能及其临床应用前景作了综述。     

镓银合金的临床应用

镓银合金是一种能代替银汞合金的新型牙齿育填材料，其性能与银汞合金相近，优点是不会对中需口腔科医护人员产生汞害。充填后有较好的耐磨性、耐腐蚀性、固化速度快。经我们临床应用于不同年龄不同部位的磨牙，二年后复查其优良率达９８．９６％、失败率１．０４％。经动物试验：对口腔粘膜及牙龈组织无刺激、无毒、无过敏反应、不污染环境是拟替代银汞合金的理想充填材料。     

根尖倒充填材料的研究进展

根尖倒充填术的目的是严密封闭根尖孔与根尖周组织的交通，预防根尖微渗漏，常用于非手术治疗失败，不能用常规方法进行根管治疔术且要尽量保留患牙的病例。由于大量材料已应用于根尖倒充填，本文对各种以往在临床和动物实验中常用的根尖倒充填材料作一简要综述。     

新型牙体修复用合金——镓合金的临床应用研究

镓合金是一种新型的牙体修复材料、它具有与银汞合金相似的性能与操作过程.与后者最大的不同是不含汞.避免汞对病员与医务人员的危害.我科应用该材料充填了58例病员,62颗牙齿.经过3个月、6个月、9个月,1年以上的随访复查,结果仅1例原为隐裂牙的复合洞型、充填后6个月脱落,另一例在9个月后变色,其余60颗牙充填后材料与牙体结合边缘密合,无因磨耗而产生的解剖形态变化.无失泽或变色,无界面染色、无继发性龋产生.作者认为镓合金可作为临床上牙体修复材料.     

不同根尖倒充填材料临床疗效分析

目的：比较不同封闭性能的充填材料在根尖倒充填治疗中的临床疗效。方法：选择近2年因常规根管治疗无法治愈行根尖切除及根尖倒充填治疗的根尖周疾患病例69例;共72颗牙（其中上颌中切牙31颗、上颌侧切牙24颗、上颌尖牙17颗）根据选择的倒充填材料分为MTA治疗组（M组）、银汞合金治疗组（Y组）、银粉玻璃离子水门汀组（B组）,每组24颗牙,三组均肉眼下进行根尖切除、倒预备及根尖倒充治疗。术后随访24月,通过临床体征及影像学评判术后疗效,统计分析术后6月、12月、24个月临床治愈率及术后短期（1周内）局部炎症反应发生率。结果：术后2年M组临床治愈率高于Y组和B组（P〈0．05）,差异有统计学意义;Y组与B组之间有效率无明显差异（P〉0．05）;术后6个月治愈率M组与Y组、M组与B组间差异有统计学意义（P〈0．05）,Y组与B组差异无统计学意义（P〉0．05）;术后1周内M组肿痛发生率略少于Y组与B组,但经统计学处理差异无统计学意义（P〉0．05）。结论：以上三种不同根尖封闭性能的充填材料均能有效提高根尖倒充填治疗的临床效果,但MTA根尖封闭性能更好,根尖倒充填的临床治愈率更高。     

镓银合金充填边缘微渗漏

本研究选择３０颗下颌磨牙,按标准制备Ⅱ类洞型,分三组分别充填镓银合金、ＧＫ高铜银汞合金、传统银汞合金,采用染料渗透法观察其充填物边缘微渗漏情况。     

镓合金用于牙体修复的临床应用研究

目的：观察镓合金作为一种新型的牙体修复材料在临床中的使用情况。方法：对48个牙体充填后经过6月、9月、12月、24月随访观察。结果：48个修复体中Ⅰ类洞40个、Ⅱ类洞6个、Ⅴ类洞2个,除4个修复体因充填后牙尖折断及乳牙替换而脱落,其余修复体均完整,无边缘折断或裂缝。优良率达95．5％。失败率4．5％。结论：镓合金对口腔黏膜及牙龈组织无刺激,无毒,无过敏反应,不污染环境,是一种良好的牙体修复材料。     

A 3-year clinical evaluation of a gallium restorative alloy

Several alternative materials have been suggested to take the place of amalgam, because of the environmental toxic effects of its mercury component. One such material is gallium-based alloy restoratives. The aim of this in vivo study was to compare the long-term clinical performance of a commercial gallium alloy with an admixed high copper amalgam alloy. For this purpose, 32 gallium and 32 amalgam restorations were placed in molar teeth in 14 human subjects. All the selected patients had at least two molar teeth that required restoration. In this way both restoratives were used in the same oral cavity. The restorations were examined at baseline, 6 months, 1, 2 and 3 years. At baseline, six teeth restored with gallium alloy showed post-operative sensitivity, whereas none of the amalgams were sensitive. At the end of 3 years, only a few amalgam restorations showed slight surface tarnish and marginal integrity loss. None of them needed replacement. Of the 32 gallium restorations placed, five had to be removed because of sensitivity, corrosion and tooth fracture. Also dramatic surface roughness and corrosion were noticed in 12 gallium restoration. According to the results of this clinical study, gallium-based restoratives should not be used before their physical properties are improved.     

镓合金和银汞合金的比较研究Ⅱ.蠕变性和临床可操作性

修复材料的蠕变值与修复体的临床寿命密切相关。蠕变值低，修复体边缘不易缺损，则修复体寿命长。本实验结果提示，镓合金的蠕变值高于银汞合金，但在ＩＳＯ范围之内，镓合金的临床可操作性较差。所以，镓合金要替代银汞合金，要改善其可操作性     

四种根尖倒封闭材料边缘微渗漏的定量比较研究

目的　比较研究四种牙体修复材料的根尖倒封闭性能。方法　用标准纸尖法和染料渗透法相结合 ,定量分析离体牙根尖倒封闭术后不同时间的边缘微渗漏情况。结果　染料浸透 7d、14d、2 8d时 ,各试验组间边缘微渗漏差异有极显著性 (P <0 .0 0 0 1) ,玻璃离子组边缘微渗漏情况明显优于合金组 (P <0 .0 5 ) ;2 8d时 ,各试验组根管内纸尖吸液体积均值的大小顺序为 :银汞合金组 >镓合金组 >自凝型GIC组 >光固化型GIC组 (P <0 .0 5 )。结论　光固化型玻璃离子粘固剂比其它三种材料具有更好的根尖倒封闭性能     

镓合金骨埋植的组织学实验研究

目的：比较镓合金和银汞合金、玻璃离子体水门汀的骨组织学反应，探讨镓合金作为根尖切除术后倒充填材料的可行性。方法：麻醉下切开48只大耳兔的股骨，暴露股骨干，每间隔5mm钻直径1mm的埋植小孔4个，自上而下依次植入镓合金、玻璃离子体水门汀、银汞合金和空白对照，进行组织学及X线对照观察。动物分别于7、28、84、168d处死，取标本制片，进行组织学观察。组织学反应以距离植入体100μm内的浆细胞、淋巴细胞、多形核白细胞、巨噬细胞、破骨细胞数目评估。骨形成以同一区域内成骨细胞存在与否判定。x线片检查分别于手术后当天及4个取材期进行。结果：镓合金植入体100μm范围内28、84d骨形成统计学上有明显差异，玻璃离子体水门汀在整个实验期内无显著差异，而银汞合金组在整个实验期内都有明显差异。镓合金组7、28d淋巴细胞浸润统计学上有明显差异，玻璃离子体水门汀组从28、84d淋巴细胞浸润有明显下降，银汞合金组从7d--84d淋巴细胞浸润有明显差异。结论：镓合金与银汞合金有相似的生物相容性，并且镓合金的细胞毒性略低于银汞合金，为镓合金作为根尖切除术后倒充填材料及龋齿窝洞充填材料的临床应用提供了依据。     

尖周刮治术和根管逆行充填术10例

目的：通过根管外科手术，治疗一些常规根管治疗疗效不佳，根管内有不能取出的充填物而不能进行常规根管治疗的患牙。方法：收集临床病例10例，除1例根充完整患牙仅行根尖周刮治术外，其余9例均在根尖周刮治术的基础上行根管倒充术。结果：治疗后观察1年10例均无不适。8例根尖病灶缩小，2例根尖病变区有新生骨小梁形成，密度较正常稍低。结论：对于由于各种原因所致的根管堵塞无法进行常规根管治疗的患牙，可通过根管外科手术予以解决。     

Handling characteristics of a palladium-free gallium-based alloy compared with a high copper dental amalgam in a simulated clinical trial

The aim of the current study was to compare the handling characteristics of a palladium-free gallium-based alloys (Galloy) with those of a high-copper amalgam (Permite C). The study had a particular interest in the evaluation of the direct placement delivery system used with both alloys. Ten dentists participated in the current study. Each placed two amalgam and two gallium-based alloy restorations in conventional class II cavities prepared in acrylic typodont teeth. None of the participating dentists had used the direct placement delivery system or had any previous experience with gallium-based alloy and no practice was allowed beforehand. The restorations were evaluated according to the following criteria: ease of loading the cavity (delivery system), ease of condensation, capacity to produce and sustain contact area, ease of carving, resistance to damage during removal of the matrix band, overall quality of the restoration and the available working time. Each criterion was given a score on a scale of 1-5 (1: very poor, 2: poor, 3: fair, 4: good, 5: very good). The results showed no statistically significant difference in the evaluated criteria between the two alloys (P > 0.05) except for criterion number 2 (ease of condensation, P=0.0005).     

Cortisomol糊剂用于老年人根管充填术后反应的近期临床观察

目的：观察Cortisomol糊剂加牙胶尖充填老年人根管后的反应并与氧化锌丁香油糊剂加牙胶尖根充后反应作对比。方法：将140颗需进行根管治疗术的患牙随机分为2组，常规根管预备、根管消毒后，分别用Cortisomol糊剂（以下称Cortisomol组）和氧化锌丁香油糊剂（以下称ZOE组）加牙胶尖进行根管充填，观察术后反应。结果：Cortisomol组与ZOE组在无痛、2d自愈以及7d自愈的发生率差异均有显著性（P〈0．05）。Cortisomol组根充后疼痛发生率和持续时间均明显低于ZOE组。结论：Cortisomol糊剂加牙胶尖充填根管可以明显减少老年人根充后疼痛的发生。     

Biocompatibility of retrograde root filling materials: a review

The aim of a retrograde filling material is to fill the apical canal space and to obtain a hermetic seal between the periodontium and the root canal system. Several materials have been suggested for root-end filling including: amalgam, gutta-percha, zinc oxide-eugenol cements, glass ionomer cement, gold foil pellets, Cavit, composite resin and mineral trioxide aggregate (MTA). Super-ethoxy benzoic acid and MTA are the most suitable materials and provide better results in apicoectomy procedures than other filling materials. Unfortunately, the ideal material for this purpose has yet to be found. This article is a review of the biocompatibility of retrograde filling materials.     

In vitro study of the sealing ability of four retrograde filling materials

Abstract This in vitro study utilized India ink dye after clearing to evaluate the extent of apical microleakage following reverse filling procedures. Forty single-rooted human teeth divided into 4 groups were chemomechanically prepared and obturated, using the lateral condensation technique with gutta-percha and Grossman sealer. Following obturation, an apicoectomy was performed and retrograde cavities were filled with 4 different materials: Group A: amalgam and varnish; Group B: EBA cement; Group C: Ketac-cem®; Group D: hot-burnished gutta-percha. All teeth were immersed in India ink, decalcified, cleaned, examined through a stereomicroscope, and the depth of linear dye penetration was measured. Statistical analysis showed significantly less dye penetration with EBA cement and amalgam with varnish than with Ketac-cem and hot-burnished gutta-percha.