牙本质无机物在牙本质粘接过程中的作用

目的探讨牙本质无机物在牙本质粘接过程中的作用。方法采用几种不同的牙本质处理方法，测试分析了牙本质与４ＭＥＴＡ／ＭＭＡＴＢＢ树脂之间的抗张粘接强度（ｔｅｎｓｉｌｅｂｏｎｄｉｎｇｓｔｒｅｎｇｔｈ，ＴＢＳ）。结果选用１０％柠檬酸和３％三氯化铁组成的酸盐体系预处理液（ａｃｉｄｓａｌｔｐｒｅｔｒｅａｔｉｎｇｓｏｌｕｔｉｏｎｓｙｓｔｅｍ，ＡＰＳＳ）去除牙本质污染层，再用次氯酸钠溶解牙本质胶原。暴露牙本质无机物时，牙本质的抗张粘接强度为５９３ＭＰａ，明显高于用蒸馏水冲洗的对照组（３７１ＭＰａ）（Ｐ＜００５）。结论说明牙本质无机物在牙本质粘接过程中确实具有一定的作用     

VLC－2型光固化粘结剂的研制

目的：研制一种可取代ＶＬＣ－１型粘结剂的新型可见光固化粘结剂。方法：按照有关试验标准和参考资料测定研制的新型粘结剂和ＶＬＣ－１型、ＤｕｒａｆｉｌＢｏｎｄ粘结剂的剪切粘结强度（ＳＢＳ）、压缩强度（ＣＳ）、径向拉伸强度（ＤＴＳ）、表面硬度（Ｈｖ）和聚合程度（ＤＰ）。结果：新型粘结剂的ＣＳ、ＤＴＳ、Ｈｖ、ＳＢＳ和ＤＰ分别为１９６．２ＭＰａ、４１．９ＭＰａ、２８６．８ＭＰａ、２８．４ＭＰａ和６３．１％，明显高于ＶＬＣ－１型粘结剂（Ｐ＜０．０１）。结论：ＶＬＣ－２型光固化粘结剂具有良好的物理机械性能，可取代ＶＬＣ－１型粘结剂。     

抗S.mutans（血清型c）细胞表面蛋白P1抗体对各型变链粘附…

目的：观察Ｓ．ｍｕｔａｎｓ遗传Ⅰ型（血清ｃ型）Ｐ１抗体对遗传Ⅱ－Ⅴ型（血清ａ－ｇ型）变链菌在唾液包羟磷灰石微珠（Ｓ－ＨＡ）表面粘附的影响。方法：用提纯的变链Ｓ．ｍｕｔａｎｓＭＴ６Ｒ的细胞表面蛋白Ｐ１加弗氏佐剂通过局部唾液腺和背部皮下注射免疫ＢＡＬＢ／ｃ鼠，得到含高效价Ｐ１抗体的鼠血清和唾液。结果：发现遗传Ⅰ型变链菌的抗Ｐ１抗体可抑制除Ｓ．ｒａｔｔｕｓ遗传Ⅱ型，血清ｂ型）以外的各型变链在Ｓ－ＨＡ表面     

绝经期妇女灼口综合征唾液免疫球蛋白的研究

目的：研究绝经期妇女灼口综合征（ＢＭＳ）患者唾液流率及免疫球蛋白的变化。方法：对２９例绝经期妇女ＢＭＳ患者及２０例无ＢＭＳ的绝经期妇女的唾液流率,ｐＨ值及静态和动态混合唾液中ＳＩｇＡ,ＩｇＧ,ＩｇＭ进行观察,并行问卷调查。结果：ＢＭＳ组静态及动态混合唾液流及ｐＨ值差异无显著性意义（Ｐ〉０．０５）,而静态和动态混合唾液ＳＩｇＡ明显低于对照组,均有显著性差异（Ｐ〈０．０１）,ＩｇＭ明显高于对照组（分别     

抗S.mutans(血清型c)细胞表面蛋白P_1抗体对各型变链粘附的影响

目的：观察Ｓ．ｍｕｔａｎｓ遗传Ｉ型（血清ｃ型）Ｐ１抗体对遗传Ⅱ～Ｖ型（血清ａ～ｇ型）变链菌在唾液包被的羟磷灰石微珠（Ｓ－ＨＡ）表面粘附的影响。方法：用提纯的变链Ｓ．ｍｕｔａｎｓＭＴ６Ｒ的细胞表面蛋白Ｐ１加弗氏佐剂通过局部唾液腺和背部皮下注射免疫ＢＡＬＢ／ｃ鼠，得到含高效价Ｐ１抗体的鼠血清和唾液。结果：发现遗传Ｉ型变链菌的抗Ｐ１抗体可抑制除Ｓ．ｒａｔｕｓ（遗传Ⅱ型，血清ｂ型）以外的各型变链在Ｓ－ＨＡ表面的粘附（Ｐ＜０．０５）。结论：蛋白Ｐ１可作为各型变链菌间的共同抗原。     

Smad4基因在人牙乳头细胞内的表达及其意义的探讨

目的：观察转化生长因子－β超家族特异的细胞内信号转导基因Ｓｍａｄ４在人牙乳头细胞内的表达,及其在转化生长因子－β１１（ＴＧＦ－β１）的骨形成蛋白－２（ＢＭＰ－２）作用下的变化,从细胞内信号转导水平探讨牙齿发育过程中成牙本质细胞的分化机制。方法：原代培养人牙乳头细胞,用ＴＧＦ－β１和ＢＭＰ－２刺激培养的细胞,分别从刺激前后的细胞中提取总ＲＮＡ和总蛋白,采用Ｎｌｒｔｈｅｒｎ和Ｗｅｓｔｅｒｎ印迹杂交方法     

含C型变形链球菌表面蛋白P1抗体的唾液膜对两种变形链球菌粘附的影响

用提纯的Ｓ．ｍｕｔａｎｓ ＭＴ６Ｒ细胞表面蛋白Ｐ１加弗氏佐剂通过局部唾液腺和背部皮下注射免疫ＢＡＬＢ／Ｃ鼠，得到含高效价Ｐ１抗体的大鼠唾液。用含Ｐ１抗体的唾液包被羟磷灰石微珠，观察含在唾液膜中的Ｃ型变链Ｐ１抗体对Ｓ．ｍｕｔａｎｓ ＭＴ６Ｒ和Ｓ．ｓｏｂｒｉｎｕｓ ６７１５在ＨＡ表面粘附的影响。     

VLC—2型光固化粘结剂的研制

研制一种可取代ＶＬＣ－１型粘结剂的新型可见光固化粘结剂，按照有关试验标准和参考资料测定研制的新型粘结剂和ＶＬＣ－１型，ＤｕｒａｆｉｌｌＢｏｎｄ粘结剂的剪切粘结强度，压缩强度，径向拉伸强度，表面硬度和聚全程度。新型粘结剂的ＣＳ，ＤＴＳ，Ｈｖ，ＳＢＳ和ＤＰ分别为１９６．２ＭＰａ，４１．９ＭＰａ，２８６．８ＭＰａ，２８．４ＭＰａ和６３．１％，明显高于ＶＬＣ－１型粘结剂。     

SOD盖髓术后牙髓组织免疫组化染色的观察

目的：探讨ＳＯＤ作为盖髓剂促进牙髓修复的作用机理。方法：应用ＢＭＰ－ＡＢＣ法对盖髓后获得成功的标本进行免疫组化染色。结果：空白组、正常对照组标本ＢＭＰ染色结果为阴性；ＳＯＤ盖髓后有牙本质桥、牙本质瘤形成的标本，ＢＭＰ染色均呈不同程度的阳性反应，显微镜下观察为黄褐色颗粒。主要分布在牙本质桥下成牙本质细胞、牙髓细胞浆中和牙髓组织。结果：ＳＯＤ用于盖髓促进牙髓组织修复、牙本质桥形成与ＢＭＰ作用有关，ＳＯＤ一方面抑制炎症反应，改善局部微环境，为组织自身修复创造条件；另一方面则刺激牙髓组织增生、诱导牙髓细胞合成分泌ＢＭＰ。     

牙周病患者牙龈组织前列腺素E_2、血栓素B_2、6－酮－前列腺素F_（1α）水平的研究

采用ＲＩＡ对１１例健康牙龈组织（Ｈ）、１１名龈炎（Ｇ）患者的１７个牙、２６名成人牙周炎（ＡＰ）患者３６个牙和１４名青少年牙周炎（ＪＰ）患者的２０个牙的牙龈组织同时测定ＰＧＥ_２、ＴＸＢ_２、６－Ｋ－ＰＧＦ_（１α）的含量。结果以ＰＧＥ_２最多，ＴＸＢ_２次之，６－Ｋ－ＰＧＦ_（１α）最少；３种前列腺素（ＰＧｓ）均随病变严重程度而增加，除Ｇ组ＴＸＢ_２和６－Ｋ－ＰＧＦ_（１α）与Ｈ组相差显著（Ｐ＜０．０５）外，其余各病变组与Ｈ组比，３种ＰＧｓ均相差非常显著（Ｐ＜０．０１），ＡＰ组和ＪＰ组比Ｇ组也有非常显著升高（Ｐ＜０．００１），而ＡＰ和ＪＰ组间相差不显著（Ｐ＞０．０５），表明３种ＰＧｓ在牙周病发病中具有重要作用。     

Effect of dentin pretreatment with mild acidic HOCl solution on microtensile bond strength and surface pH

Objectives

To evaluate the pretreatment effect of mild acidic HOCl solution on the microtensile bond strength (μTBS) of a two-step self-etch adhesive to dentin and the alteration of dentin surface pH.

Methods

Thirty-nine flat ground coronal dentin specimens were divided into one control group and 12 experimental groups, which were treated with 6% NaOCl or 50, 100 and 200 ppm HOCl (Comfosy^®) solutions for 5, 15 and 30 s. After rinsing with running water for 30 s, all the dentin surfaces were bonded with Clearfil SE Bond according to the manufacturer's instructions. After 24 h water storage, the bonded specimens were sectioned and trimmed to an hourglass shape with a cross-sectional area of approximately 1.0 mm² and then subjected to the μTBS test. Thirty-six mid-coronal dentin discs were used for surface pH measurement. Dentin surface pH with or without pretreatment was examined using a pH-imaging microscope (SCHEM-100). The μTBS data were analyzed by one-way ANOVA (Dunnett's T3) and the surface pH data were analyzed by non-parametric statistics (Mann–Whitney U-test).

Results

Pretreatment with Comfosy^® at concentrations of 50, 100 and 200 ppm did not significantly affect μTBS regardless of the application time compared with the control group, however the 100 and 200 ppm Comfosy^® groups showed significantly lower surface pH values. For the NaOCl pretreatment groups, a longer application time significantly decreased the μTBS and increased the surface pH values compared to the control group.

Conclusions

The 50 ppm Comfosy^® pretreatments for 5, 15 and 30 s did not affect the μTBS of the two-step self-etch adhesive to dentin and dentin surface pH.     

Effect of different surface treatments of human occlusal sclerotic dentin on micro-tensile bond strength to resin composite core material

The objectives of this study were to evaluate the micro-tensile bond strength (μTBS) of composite bonded to human occlusal sclerotic dentin following different surface treatments to determine the sclerotic dentin morphology. Human molars without (normal dentin; group 1) or with occlusal wear (sclerotic dentin; groups 2–5) were divided and subjected to different surface treatments, including the normal protocol for the Contax self-etch bonding system (group 1 and 2); doubled etch-prime time (group 3); pre-conditioning with 37% phosphoric acid before normal protocol (group 4); or pre-conditioning with 37% phosphoric acid before doubling the self-etching time (group 5). All teeth were restored with composite (Luxacore Z dual), sectioned into stick specimens and stored for 24 h in water before specimens were subjected to the μTBS test (n = 50 per group). The μTBS of normal dentin was not statistically significantly different from that of the sclerotic dentin groups, except for the doubled etch-prime time group which showed lower μTBS. Sclerotic dentin pre-treated with phosphoric acid resulted in less sclerotic casts and wider dentinal tubules, while doubled etch-prime time did not alter the morphology, as shown by scanning electron microscopy. In conclusion, the use of 37% phosphoric acid before applying self-etch bonding resulted in more tubule openings and a significantly higher μTBS when compared with the doubled etch-prime time group.     

Effect of pretreatment with mildly acidic hypochlorous acid on adhesion to caries-affected dentin using a self-etch adhesive

Caries-affected dentin is covered with a thicker and organically enriched smear layer than normal dentin. This may affect the demineralization ability and the infiltration of self-etch adhesives, thus reducing the efficacy of bonding to caries-affected dentin. This study evaluated the adhesion of a two-step self-etching adhesive to normal and caries-affected dentin after pretreatment with mildly acidic hypochlorous acid (HOCl) solutions. We used a microtensile bond strength (μTBS) test to compare the μTBS of Clearfil SE Bond to either caries-affected dentin or to normal dentin, after pretreatment for 5 s with one of three solutions (806 mM NaOCl, or 0.95 or 1.91 mM HOCl). The μTBS of the self-etch adhesive was significantly lower to caries-affected dentin than to normal dentin. Pretreatment with 0.95 mM HOCl improved the μTBS of the self-etch adhesive to caries-affected dentin, but there was no significant difference compared with normal dentin. On the other hand, pretreatment with 806 mM NaOCl or 1.91 mM HOCl did not demonstrate a significant improvement in the μTBS to caries-affected dentin. None of the pretreatments demonstrated a negative effect on adhesion to normal dentin.     

The durability of adhesion to phosphoric acid etched, wet dentin substrates.

OBJECTIVE: The purpose of this study was to investigate the influence of remaining non-resin-impregnated, phosphoric acid demineralized dentin upon the long-term durability of specimens that were wet-bonded to bovine dentin substrates. METHODS: Prepared bovine dentin samples were etched with 65% phosphoric acid then rinsed with water and kept wet during application of 5 wt% 4-methacryloyloxyethyl trimellitate anhydride (4-META) in acetone primer. This was followed by application of a photocured dentin-bonding agent consisting of 4-methacryloyloxyethyl trimellitate anhydride/triethyleneglycol dimethacrylate-camphorquinone/N-phenylglycine (4-META/TEGDMA-CQ/NPG). The tensile bond strength (TBS) of bonded specimens was determined after immersion in 37 degrees C water for various time intervals. Generated data were analyzed for statistical significance by one-way ANOVA and Duncan's New Multiple Range Test (p < 0.05). The dentin side of the tensile-load-fractured specimens was examined under optical and scanning electron microscopes (SEM). RESULTS: TBS decreased from 6.6 +/- 1.0 MPa after 1-day water immersion to 3.4 +/- 1.7 MPa after 1 month of water immersion. After 6 months of water immersion, TBS was found to be 3.9 +/- 0.9 MPa and this decreased to 2.0 +/- 1.0 MPa for specimens immersed in water for 1 year, a statistically significant difference (p < 0.05). Optical microscopic and SEM observations disclosed failure patterns within demineralized, non-resin-impregnated dentin that increased with the period of water immersion. SIGNIFICANCE: The bond durability to wet dentin was poor when demineralized dentin was not resin-impregnated, resulting in exposure of collagen fibrils which hydrolyzed during long periods of water immersion.     

Temporary zinc oxide–eugenol cement: eugenol quantity in dentin and bond strength of resin composite

Uptake of eugenol from eugenol‐containing temporary materials may reduce the adhesion of subsequent resin‐based restorations. This study investigated the effect of duration of exposure to zinc oxide–eugenol (ZOE) cement on the quantity of eugenol retained in dentin and on the microtensile bond strength (μTBS) of the resin composite. The ZOE cement (IRM Caps) was applied onto the dentin of human molars (21 per group) for 1, 7, or 28 d. One half of each molar was used to determine the quantity of eugenol (by spectrofluorimetry) and the other half was used for μTBS testing. The ZOE‐exposed dentin was treated with either OptiBond FL using phosphoric acid (H₃PO₄) or with Gluma Classic using ethylenediaminetetraacetic acid (EDTA) conditioning. One group without conditioning (for eugenol quantity) and two groups not exposed to ZOE (for eugenol quantity and μTBS testing) served as controls. The quantity of eugenol ranged between 0.33 and 2.9 nmol mg^?1 of dentin (median values). No effect of the duration of exposure to ZOE was found. Conditioning with H₃PO₄ or EDTA significantly reduced the quantity of eugenol in dentin. Nevertheless, for OptiBond FL, exposure to ZOE significantly decreased the μTBS, regardless of the duration of exposure. For Gluma Classic, the μTBS decreased after exposure to ZOE for 7 and 28 d. OptiBond FL yielded a significantly higher μTBS than did Gluma Classic. Thus, ZOE should be avoided in cavities later to be restored with resin‐based materials.     

Dentin thickness, hardness, and Ca-concentration vs bond strength of dentin adhesives.

The relationship between the tensile bond strength (TBS) and three dentin characteristics: remaining dentin thickness (RDT), Ca-concentration, and hardness, were investigated. Sixty-two extracted bovine incisors, divided into four groups, were prepared using 600-grit SiC paper to create flat dentinal surfaces. The materials tested in this study consisted of three commercially available and one experimental dentin bonding systems. The TBS and modes of failure were determined after storage for 24 h in 37 degrees C water. Then RDT, Ca-concentration, and hardness were measured. Data were statistically compared with TBS of each group. The mean bond strength of the commercial materials ranged from 2.5 +/- 0.9 MPa to 7.7 +/- 2.8 MPa. Correlations with Ca-concentration and RDT varied, depending on the product. The bond strength of the experimental material was 9.2 +/- 4.4 MPa and significantly correlated with RDT and hardness. With two of the dentin bonding agents, specimens showed a high number of cohesive fractures in dentin, 40% to 82%. It was concluded that the variability of TBS was influenced by dentinal characteristics in three of the four materials tested.     

生物活性玻璃改性树脂粘接剂对牙本质脱矿及树脂粘接强度的影响

目的 研究生物活性玻璃（BG）改性树脂粘接剂抑制牙本质脱矿及对树脂-牙本质微拉伸粘接强度的影响。方法 将硅烷偶联剂表面处理后的BG与Single Bond 2粘接剂混合制备出30%、40%和50%的BG改性的树脂粘接剂,选择上颌前磨牙40颗,随机分为4组,阴性对照组（不添加BG）、30%BG组、40%BG组、50%BG组,每组10颗。根据分组分别采用相应BG含量的粘接剂制备树脂-牙本质粘接试件。将制备的粘接试件在37 ℃水浴中浸泡24 h后进行微拉伸粘接强度测试。每组选择1个牙片浸泡在pH 4.0的人工唾液中1周,每24 h测试溶液的pH值。结果 阴性对照组、30%BG组、40%BG组、50%BG组的粘接强度分别为（27.76±0.29）、（27.05±0.58）、（26.95±0.69）和（25.12±0.24）MPa。对照组和30%BG组的粘接强度无统计学差异（P=0.06）,和40%BG组、50%BG组有统计学差异（P=0.04,P=0.00）;30%、40%BG组的粘接强度高于50%BG组（P=0.00,P=0.00）。随着BG含量的增加,pH值也逐渐增高。结论 含有BG的树脂粘接剂可以有效抑制牙本质的脱矿,30%BG组对短期的粘接强度无明显影响,50%BG组抑制脱矿能力最强,但是粘接强度较低。     

Effect of a caries-detecting solution on the tensile bond strength of four dentin adhesive systems

This study investigated the effect of a caries-detecting solution on the tensile bond strength (TBS) to sound bovine dentin--which was either rinsed thoroughly of or contaminated with the caries-detecting solution. Caries Detector (1.0% acid red in propylene glycol) was applied on flat dentin surfaces for 10 seconds, rinsed, and dried with syringe air. In another group, Caries Detector was not rinsed but air-dried. Then, the surfaces were treated with one of the following adhesive systems: Clearfil Protect Bond, Clearfil SE Bond, One-Up Bond F, or Single Bond. Furthermore, an ingredient of Caries Detector, either 1.0% acid red aqueous solution or propylene glycol, was applied to evaluate the effect of each component. In the control groups, Caries Detector was not applied to the dentin surfaces. Finally, a resin composite was light-cured and the TBS measured. Fractured specimens and treated dentin surfaces were observed by SEM. Caries Detector did not reduce the tensile bond strength of any adhesive system (p>0.05) when rinsed thoroughly. On the other hand, when dentin surface was contaminated with Caries Detector, TBS decreased significantly with Clearfil SE Bond and Single Bond. As for the ingredients of Caries Detector, the effect of acid red on TBS was not significant, but that of propylene glycol was significant.     

杨梅素对脱矿牙本质再矿化及树脂-牙本质粘接效果的影响

目的 评价杨梅素(myricetin,MYR)对脱矿牙本质基质的再矿化效果及其对牙本质粘接强度的影响。方法 切取中层牙本质,使用600目碳化硅砂纸湿抛光模拟玷污层,35%磷酸酸蚀后分别给予蒸馏水浸泡、直接再矿化处理2 d和MYR预处理30 min后再矿化处理2 d。采用扫描电镜(scanning electron microscope,SEM)观察样本表面形态,X射线衍射(X-ray diffraction,XRD)和衰减全反射傅里叶变换红外光谱(attenuated total reflection Fourier transform infrared spectroscopy,ATR-FTIR)分析表面物质,微拉伸强度(micro tensile strength,μTBS)和纳米渗漏实验观察粘接效果。结果 SEM发现再矿化处理的各组牙本质片均可以形成晶体,其中经MYR预处理后再矿化的样本形成的晶体最为明显,新形成的晶体经XRD和ATR-FTIR分析为羟基磷灰石。μTBS和纳米渗漏实验发现MYR预处理后的牙本质试件再矿化可明显增加粘接强度,减少纳米渗漏。结论 MYR预处理可以促进脱矿牙本质的再矿化过程并改善树脂-牙本质粘接强度。