表面镀金钴铬合金烤瓷冠对牙龈染色的影响

目的 评价钴铬合金烤瓷冠镀金预防牙龈染色的临床效果.方法 选择2颗对称性上前牙进行钴铬合金烤瓷修复的患者共51例,2颗上前牙随机分为试验组和对照组,试验组51个烤瓷冠镀金,用松风CX黏接剂黏固,对照组51个烤瓷冠不镀金,用松风CX黏接剂黏固.观察黏固后即刻颈部牙龈效果以及3个月和1年后颈部牙龈情况.结果 即刻效果试验组与对照组无显著差异.3个月后试验组有2个冠牙龈染色,对照组有7个冠牙龈染色.1年后试验组有2个冠牙龈染色,对照组有9个冠牙龈染色.3个月和1年后试验组和对照组差异均有统计学意义(P＜0.05).结论 钴铬合金烤瓷冠镀金能有效地预防牙龈染色,而且安全、实用,值得推广.     

车针粒度对预备牙体与水门汀粘固强度的影响

目的：比较不同粒度金刚砂车针预备的牙面与聚羧酸锌水门汀的粘固强度。方法：分别采用4种不同粒度车针依次打磨4组牙本质片,测量其粗糙度,并采用扫描电镜观察;再将牙本质片与聚羧酸锌水门汀粘固,测试各组剪切强度。结果：4种粒度车针预备的牙面粗糙度间存在显著差异（P〈0.01）;聚羧酸锌水门汀与各组牙面的粘固强度间也存在显著差异（P〈0.05）。结论：随预备用车针粒度的减小,牙面粗糙度降低,聚羧酸锌水门汀与牙面的粘固强度也相应降低。     

2种常用粘接剂在修复体粘固后可以使用电动牙刷的时机

目的:探讨2种常用粘接剂在修复体粘固后可以使用电动牙刷的时机.方法:将60颗离体前磨牙用管状模具包埋在自凝树脂中,高速手机去除颊面釉质,用水砂纸流水下磨平牙本质粘接面.将30个样本用聚羧酸锌水门汀粘接30个直径4 mm、高2 mm的钴铬合金试件,剩余样本用PanaviaTM F粘接30个直径4mm、高2 mm的氧化锆试件,分别分为5组(n=6).第1～4组分别在粘固后即刻、12、24、48 h后使用电动牙刷刷洗30s,第5组为对照组.刷洗后行剪切试验,体视显微镜观察离断面类型.结果:聚羧酸锌水门汀:第1、2、3组与剪切强度均小于对照组(P＜0.05),第4组与对照组比较P＞0.05.PanaviaTM F:第1、2组剪切强度均小于对照组(P＜0.05),第3、4组与对照组比较P ＞0.05.离断面类型以内聚破坏为主.结论:使用聚羧酸锌水门汀和PanaviaTM F粘固之后可使用电动牙刷的时机分别为48 h和24h.     

镀金钴铬合金烤瓷冠的临床评价

目的评价镀金钴铬合金烤瓷冠对牙龈健康的影响,为临床应用提供参考。方法根据患者对金属烤瓷单冠类型的选择,将253例患者316颗患牙分为2组。镀金组125颗患牙,镀金钴铬合金烤瓷冠修复,基底冠内表面镀金处理;对照组191颗患牙行普通钴铬合金烤瓷冠修复,基底冠表面无特殊处理。患牙相邻的健康牙或对侧同名健康牙为其组内对照牙。1年后观察2组烤瓷冠颈缘灰线发生情况,观察2组烤瓷冠及其组内对照牙的牙龈颜色、牙龈指数（gingival index,GI）、菌斑指数（plaque index,PLI）、探诊深度（probing depth,PD）。结果1年后对照组191个烤瓷冠有21个出现颈缘灰线,镀金组125个烤瓷冠有3个出现颈缘灰线,2组颈缘灰线的出现率差异有统计学意义（P〈0.05）。对照组烤瓷冠的GI较其组内对照牙增加0.75,差异有统计学意义（P=0.02）;镀金组烤瓷冠的GI较其组内对照牙增加0.09,差异无统计学意义（P=0.11）;2组烤瓷冠与其组内对照牙PLI的差异均无统计学意义（P〈0.05）;2组烤瓷冠与其组内对照牙PD的差异均无统计学意义（P〈0.05）。结论镀金钴铬合金烤瓷冠出现颈缘灰线少于普通钴铬合金烤瓷冠。     

金属瓷聚体冠修复后发生颈缘灰线的临床观察

目的:评价金属瓷聚体全冠修复后对颈缘灰线的影响.方法:将前牙需进行烤瓷修复的病例随机分为2组,一组采用金属瓷聚体全冠修复.另一组采用普通金属烤瓷全冠(PFM)修复.观察修复后颈缘灰线的发生情况.结果:修复后即刻2组发生颈缘灰线的比例无显著性差异.戴牙3个月后两组龈灰线的发生无显著性差异(p＞0.05);戴牙1年后治疗组龈灰线发生明显少于对照组,有显著性差异(p＜0.05).结论:金属瓷聚体全冠修复发生颈缘灰线的比例较少,与普通金属烤瓷全冠(PFM)相比具有较好的修复效果.     

增殖细胞核抗原、bcl-2在灰线牙龈组织中的表达

目的　研究增殖细胞核抗原(PCNA)、bcl-2蛋白在灰线牙龈组织和正常牙龈组织中的表达,探讨瓷熔附金属全冠修复的生物学效果。方法　采用免疫组化SP法,以瓷熔附金属全冠修复后建立出的家兔灰线牙龈实验动物模型为研究对象,检测PCNA、bcl-2蛋白在戴金属烤瓷全冠3个月组、戴金属烤瓷全冠6个月组和不戴金属烤瓷全冠组即对照组牙龈组织中的表达。结果　戴金属烤瓷全冠3个月组与对照组PCNA有显著性差异(P<0·05); 戴金属烤瓷全冠6个月组与对照组PCNA没有显著性差异(P>0·05)。戴金属烤瓷全冠3个月组、戴金属烤瓷全冠6个月组与对照组bcl-2差异无显著性(P>0·05)。结论　PCNA表达与灰线牙龈组织炎症反应有关;PCNA、bcl-2 的表达,不表明灰线牙龈组织有异常增殖。     

非贵金属烤瓷冠修复后牙龈组织和血液中镍铬元素含量分析

医学院附属口腔医院　修复科,贵州　遵义563003;2.遵义市环保监测站,贵州　遵义563000) [摘要]　目的　研究家兔前牙行非贵金属烤瓷冠修复后牙龈组织及血液中镍铬元素的含量,初步探讨产生牙龈灰线的原因。方法　选38只成年家兔为实验对象,备其上下前牙,用德国Vita非贵金属烤瓷合金制作烤瓷冠,粘固。 3个月及6个月后用石墨炉原子吸收光谱法对实验区龈组织和血液进行镍铬元素含量分析。结果　非贵金属烤瓷冠修复后6个月组的牙龈组织和血液中镍铬元素含量均比对照组及3个月组高(P<0.05)。3个月组的牙龈组织和血液中镍铬元素含量与对照组相比无差异(P>0.05)。结论　非贵金属烤瓷冠暴露于口腔环境中,并与牙龈组织及体液直接接触,其金属边缘很容易发生电化学腐蚀,造成金属离子游离于牙龈组织和血液中,一定时间后引起牙龈灰线。     

镀金烤瓷冠与镍铬合金烤瓷冠用于前牙美学修复的比较研究

目的探讨镀金烤瓷冠用于前牙美容修复的临床效果。方法70个单位的镀金烤瓷冠和78个单位的镍铬合金烤瓷冠进行上前牙美容固定修复,对比评价修复效果。结果镀金烤瓷冠和镍铬合金烤瓷冠在外形、色泽等方面无明显差异。镀金烤瓷冠与镍铬合金烤瓷冠相比,较少出现烤瓷冠边缘牙龈变色和牙龈灰线。结论镀金烤瓷冠用于前牙美容修复可获得良好的美学效果。     

2种水门汀粘固金属烤瓷冠的临床应用比较

粘固是ＰＦＭ冠修复过程中一环。正确选择粘固所用水门汀 ,对ＰＦＭ冠的固位十分重要。本文比较了玻璃离子水门汀和聚羧酸锌水门汀粘固ＰＦＭ冠的临床应用效果。1　材料与分组玻璃离子水门汀 (ＧＩＣ ,上海齿科材料厂生产 ) ,聚羧酸锌水门汀 (ＰＣ ,上海齿科材料厂生产 )。牙体制备、取模、戴牙均由我科医生完成 ,粘固前均戴暂时冠护髓。ＰＦＭ冠由深圳美冠达牙科技术有限公司制作。将 4 0例共 12 4个ＰＦＭ冠粘固时随机分为二组 ,Ｉ组为ＧＩＣ组 ;ＩＩ组为ＰＣ组。每组 6 2牙 ,不分年龄、性别、牙位。2　方法ＰＦＭ冠试戴满意后 ,仔细清洗 …     

镀金技术在镍铬合金烤瓷修复中的临床应用

目的：探索解决镍铬合金制作金属烤瓷冠（桥）因氧化腐蚀引起的边缘变色、颈缘灰线等问题的方法。方法：将139例,284修复单位随机分为两组,实验组87例,184单位,为镀金的镍铬合金烤瓷冠,对照组52例,100单位,为普通的镍铬合金烤瓷冠。修复1年后检查烤瓷冠的边缘变色、颈缘灰线和牙龈健康情况,对比评价复查结果。结果：两组病例,在边缘变色、颈缘灰线和牙龈健康三方面均有一定差异,其中牙龈健康情况的差异无统计学意义（P〉0．5）,边缘变色和颈缘灰线方面有显著性差异（P〈0．01）。结论：镍铬合金烤瓷修复体金属表面镀金的防腐处理,方法简便,材料性能安全,成本较低,效果良好。     

Clinical studies of dental cements: V. Recall evaluation and a zinc phosphate cement.

Patients with restorations cemented with a reinforced zinc oxide-eugenol cement and a zinc phosphate cement were recalled after a four- to seven-year interval. No significant differences in clinical success were observed between restoration luted with the two cements. No significant difference in the incidence of caries at the restoration margins was noted between the cements.     

特殊粘接技术在前牙美学区种植修复中的应用

目的介绍一种前牙美学区种植修复的特殊粘接技术,并评价其临床疗效。方法选择60例单个前牙种植修复患者,均采用粘接固位,粘接边缘位于龈下1¹.5 mm。对照组采用传统粘接技术,实验组采用特殊粘接技术。修复完成1个月和6个月后分别统计两组的改良牙龈出血指数、龈沟深度和修复体脱落率。结果修复后1个月,实验组的改良牙龈出血指数显著优于对照组,其它指标无统计学差异;修复后6个月,两组各项指标无统计学差异。结论本研究介绍的特殊粘接技术有助于在修复后早期减少粘接剂残留引起的种植体周围炎,提升牙龈健康水平。     

Seating and retention of complete crowns with a new adhesive resin cement.

The retentive property of cast gold complete crowns cemented with an adhesive resin cement (Panavia Ex) was compared with retention of crowns cemented with zinc phosphate cement (Flecks) and the conventional resin cement (Comspan). The effect of these agents on seating of crowns also was evaluated. Panavia cement exhibited the highest retentive strength, with values almost twice those obtained with zinc phosphate cement. However, the difference in mean retention values of crowns cemented with Comspan cement or with zinc phosphate cement was not statistically significant. Both resin cements used in this study provided better seating of crowns than did zinc phosphate cement.     

Retentive strength, disintegration, and marginal quality of luting cements.

This study evaluated the retention of complete crowns by using five different methods of cementation. Complete crowns were prepared with standardized dimensions on extracted human molars. Metal crowns were cast with a high noble gold ceramic alloy and were cemented with zinc phosphate cement, glass ionomer cement, composite resin cement, composite resin cement with a dentinal bonding agent, and adhesive resin cement. The retention was measured by subjecting the specimens to tensile load until fracture occurred. The disintegration was measured according to American Dental Association Specification No. 8, and the condition of the cements at the margins of crowns was analyzed by use of a scanning electron microscope. Kruskal-Wallis one-way analysis of variance revealed statistically significant differences between the mean retentive strengths. The retention of the zinc phosphate and the glass ionomer groups was significantly different from that of the adhesive resin group. The retention of the adhesive resin cement was 65% greater than the retention of the composite resin and the composite resin/dentinal bonding agent group, but the Mann-Whitney Wilcoxon rank sum test did not depict this difference as significant. The mean +/- SD of the disintegration for the zinc phosphate, the glass ionomer cement, and the composite resin cement was 0.025 +/- 0.013, 0.023 +/- 0.011, and 0.017 +/- 0.001, respectively. The scanning electron microscope analysis of the margins revealed that the composite resin cement was almost intact, the zinc phosphate was subjected to limited disintegration, and the glass ionomer displayed the worst marginal integrity.     

Margins of complete crowns—Literature review

The margin is one of the components of the cast restoration most susceptible to failure, both biologically and mechanically. Most of the investigative proof shows that supragingival margins are kinder to the gingiva than are subgingival margins. However, practicality dictates that supragingival margins are not always usable. There is some indication that quality of the margin may be of as much importance to gingival health as location. Research on the configuration of margins seems to agree with the majority of authors writing technical articles. Most agree that feather edge or knife edge margins are not always the most acceptable. Apparently bulky margins with subtle internal line angles are best. Bevels are recommended where esthetics allows due to their slip-joint effect affording closer adaptation.Most cemented castings do not fit nearly as well as theoretical tests of cement film thicknesses would lead us to believe. Venting or providing space for cement through electromilling, aqua regia etching, or die spacing markedly improves the seating and, therefore, the marginal fit of castings. This seems to be a more useful approach to close fitting margins than burnishing and finishing margins, particularly for subgingival margins. Most of the commonly used fixed partial denture alloys, both precious and non-precious, are too hard to be burnished effectively.As long as fixed prosthodontics must rely on the cemented casting, the search for more knowledge about an innocuous, esthetic, indestructible margin must continue.     

In vitro evaluation of secondary caries development in enamel and root dentin around luted metallic restoration

Materials that release fluoride have been recommended for patients with high caries risk, but there is no conclusive evidence of their effect on fixed prostheses abutments. This study evaluated the influence of a resin-modified glass-ionomer cement on in vitro caries development in enamel and root dentin around metallic restoration. The cervical portion of 12 human third molars were sectioned in four blocks that were randomly divided into four Groups (n = 12; 1 block from each tooth/group): ZP (restoration + zinc phosphate cement), GI (restoration + resin-modified glass-ionomer cement), C1 (no restoration and no pH cycling), and C2 (no restoration and pH cycling). In ZP and GI, metallic restorations were luted at the crown-root junction. ZP, GI and C2 were submitted to a pH-cycling model. All blocks were sectioned, embedded and polished. Enamel and root dentin demineralization were evaluated through cross-sectional microhardness Knoop measures at 20 to 80 microns of depth (from the outer surface) and at 20 to 220 microns of distance from the cavity margins. Mineral loss values were calculated from Knoop hardness numbers. Data were analyzed by ANOVA, Tukey's test and regression analysis. Groups ZP, GI and C2 showed demineralization in relation to C1, which was more superficial in enamel than in root dentin. In root dentin, mineral loss in ZP and GI was smaller than in C2. Distance from the cavity margins was not significant. There was no difference between resin-modified glass-ionomer cement and zinc phosphate cement regarding artificial secondary caries development in both dental substrates.     

Pulpal reaction to polycarboxylate and zinc phosphate cements used with inlays in deep cavity preparations.

The purpose of the present investigation was to compare histologically pulpal reactions beneath inlays cemented with either a zinc phosphate or a polycarboxylate cement. No inflammatory reaction was seen beneath any of the 39 deep cavity preparations in teeth without pulpal lesions and with an inlay cemented with polycarboxylate cement. In the contralateral teeth, under 39 inlays cemented with zinc phosphate cement, an inflammatory reaction was seen beneath two cavity preparations. In one, bacteria were found on the floor of the preparation. On the basis of this result and the findings of our earlier investigations, it may be warranted to conclude that neither the polycarboxylate cement nor the zinc phosphate cement has any notable irritating effect on the pulp. If the irritation occurs after cementation of the restoration, it may be caused by debris containing bacteria and left behind on the prepared surfaces by bacterial growth from the surface of the tooth. The findings underline the importance of removing grinding debris and bacteria before cementation of the restoration.     

An effect of immediate dentin sealing on the shear bond strength of resin cement to porcelain restoration

PURPOSE

The aim of this study was to determine differences in shear bond strength to human dentin using immediate dentin sealing (IDS) technique compared to delayed dentin sealing (DDS).

MATERIALS AND METHODS

Forty extracted human molars were divided into 4 groups with 10 teeth each. The control group was light-cured after application of dentin bonding agent (Excite® DSC) and cemented with Variolink® II resin cement. IDS/SE (immediate dentin sealing, Clearfil™ SE Bond) and IDS/SB (immediate dentin sealing, AdapterTM Single Bond 2) were light-cured after application of dentin bonding agent (Clearfil™ SE Bond and Adapter™ Sing Bond 2, respectively), whereas DDS specimens were not treated with any dentin bonding agent. Specimens were cemented with Variolink® II resin cement. Dentin bonding agent (Excite® DSC) was left unpolymerized until the application of porcelain restoration. Shear strength was measured using a universal testing machine at a speed of 5 mm/min and evaluated of fracture using an optical microscope.

RESULTS

The mean shear bond strengths of control group and IDS/SE group were not statistically different from another at 14.86 and 11.18 MPa. Bond strength of IDS/SE group had a significantly higher mean than DDS group (3.14 MPa) (P < .05). There were no significance in the mean shear bond strength between IDS/SB (4.11 MPa) and DDS group. Evaluation of failure patterns indicates that most failures in the control group and IDS/SE groups were mixed, whereas failures in the DDS were interfacial.

CONCLUSION

When preparing teeth for indirect ceramic restoration, IDS with Clearfil™ SE Bond results in improved shear bond strength compared with DDS.     

In vitro dentine permeability: the relative effect of a dentine bonding agent on crown preparations

OBJECTIVE: The aim of this study was to determine whether a dentine bonding agent (DBA) had an effect in reducing fluid filtration under cemented provisional crowns. METHODS: Crown preparations on 34 premolars, randomly allocated to two equal-sized test and control groups, were assessed for dentine permeability by a fluid filtration technique. In the test group, prepared crowns were acid-etched and then treated with a DBA (Prime & Bond NT). In the control group, no such DBA was applied. Provisional crowns were cemented on both groups of teeth using non-eugenol zinc oxide cement. Fluid filtration rates were measured repeatedly after crown preparation, at cementation, 1 h, 1 day, 1 week and 3 weeks following crown cementation for both groups. Filtration rates were also measured after acid-etching and dentine bonding for the test group. RESULTS: There was insufficient evidence to suggest any statistically significant differences either between the two groups or, on average, across the five time points in each group in terms of the relative percentage of fluid filtration. CONCLUSION: The DBA used did not seal dentinal tubules any more than did the smear layer and provisional crowns luted with a non-eugenol ZnO cement.     

超声龈上洁治术对全瓷冠边缘微渗漏的影响

目的：探讨超声龈上洁治术对全瓷冠边缘微渗漏的影响。方法：收集形态、大小基本一致的前磨牙48颗,全瓷冠牙体预备后随机分为2组（二氧化锆冠组和玻璃陶瓷冠组,每组24颗）,每组再随机分为2个亚组（树脂水门汀组和树脂改性玻璃水门汀组）。修复体粘接、固化、人工唾液保存24 h后,每个亚组内随机抽取3个样本进行超声龈上洁治60 s,另外3个样本为阴性对照组。将所有样本于室温下用5%品红溶液浸泡48 h,沿颊舌向切开,对样本冠边缘微渗漏情况进行双盲评分。采用SPSS 17.0软件包进行独立样本t检验,比较各组样本中修复体冠边缘微渗漏差异。结果：使用树脂加强型玻璃水门汀粘接的冠边缘微渗漏在超声龈上洁治后与阴性组有显著差异（P<0.05）,而使用树脂水门汀粘接的冠边缘微渗漏在超声龈上洁治后与阴性组无显著差异（P>0.05）。采用同种粘接剂时,无论是否接受超声龈上洁治术,二氧化锆全瓷冠与玻璃陶瓷冠之间微渗漏均有统计学差异（P<0.05）。结论：超声龈上洁治对树脂加强型玻璃水门汀粘接的二氧化锆和玻璃陶瓷冠边缘微渗漏有显著影响,而对树脂水门汀粘接的二氧化锆和玻璃陶瓷冠边缘微渗漏无显著影响。