Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly di...Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly divided into 2 groups with 6 teeth each.In group 1,each tooth was hemisected into two halves.One half was assigned to control subgroup 1,which was bonded with a single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 1 in which the adhesive was applied three times before light curing.In group 2,the teeth were also hemisected into two halves.One half was assigned to control subgroup 2,which was bonded with the single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 2 in which three layers of adhesive were applied with light curing each successive layer.Microtensile bond strength was immediately tested after specimen preparation.Results When the adhesive was applied three times before light curing,the bond strength of the experimental subgroup 1(n=33,57.49±11.61 MPa) was higher than that of the control subgroup 1(n=31,49.71±11.43 MPa,P<0.05).When using the technique of applying multiple layers of adhesive with light curing each successive layer,no difference of immediate bond strength was observed between the control subgroup 2 and the experimental subgroup 2(P>0.05).Conclusion Multiple coatings of one-step self-etching adhesive can increase the immediate bond strength to primary dentin when using the technique of light-curing after applying three layers of adhesive.展开更多
Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin. Methods Twelve caries-free human primary molars were randomly divided into 2 gro...Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin. Methods Twelve caries-free human primary molars were randomly divided into 2 groups. In group 1, each tooth was hemisected into 2 halves. One half was assigned to the control subgroup 1, which was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instruc- tions; the other half was assigned to experimental subgroup 1, in which the adhesive was applied three times before light curing. In group 2, one split half tooth was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instructions; for the other half, three layers of adhesive were applied with each successive layer of light curing. Specimens were stored in 0.9% NaC1 containing 0.02% sodium azide at 37℃ for 18 months and then were subjected to microtensile bond strength test and the fracture mode analysis. Results When the adhesive was applied three times before light curing, the bond strength of the ex- perimental subgroup 1 was significantly higher than that of the control subgroup 1 （47.46__＋13.91 vs. 38.12＋11.21 MPa, P〈O.05）. When using the technique of applying multiple layers of adhesive with each successive layer of light curing, no difference was observed in bond strength between the control subgroup and the experimental subgroup （39.40＋8.87 vs. 40.87-＋9.33 MPa, P〉O.05）. Conclusion Multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin when using the technique of light-curing after applying 3 layers of adhesive.展开更多
The purpose of this study was to evaluate the influence of acid etching on the bond strength of a universal adhesive system (Single Bond Universal, 3M) to caries-affected dentin. Forty permanent third molars were sele...The purpose of this study was to evaluate the influence of acid etching on the bond strength of a universal adhesive system (Single Bond Universal, 3M) to caries-affected dentin. Forty permanent third molars were selected and carious lesions were induced by the microbiological method with?S. mutans?ATCC25175. Teeth were allocated randomly across four experimental designs (n?=?10): PA-I: phosphoric acid etching and application of the adhesive system, followed by immediate microtensile bond strength testing;PA-CC: phosphoric acid etching and application of the adhesive system, followed by microtensile bond strength testing after a 14-day cariogenic challenge;NPA-I: application of the adhesive system without acid etching, followed by immediate bond strength testing and NPA-CC: application of the adhesive system without acid etching followed by bond strength testing after 14-day cariogenic challenge. For microtensile bond strength testing,?a restoration with Charisma composite resin was made and each specimen was sectioned with a cross-sectional area of 1 mm2. Only adhesive and mixed fractures were considered for bond strength calculation. Results were evaluated by the Kruskal-Wallis and Friedman tests. The highest bond strengths were observed in the phosphoric acid etching groups (p??0.05). Cariogenic challenge did not affect bond strength (p?>?0.05). The predominant fracture type was adhesive. We conclude that phosphoric acid increased the bond strength of the Single Bond Universal system to caries-affected dentin, and that cariogenic challenge did not interfere with this bond strength.展开更多
Background: To date there is not a material considered ideal for the lased dentin. Objective: To compare the bond strength to human lased dentin of self-etch and etch-and-rinse adhesive systems, a self-adhesive resin ...Background: To date there is not a material considered ideal for the lased dentin. Objective: To compare the bond strength to human lased dentin of self-etch and etch-and-rinse adhesive systems, a self-adhesive resin composite and a glass-ionomer cement. Methods: Forty human molars were sectioned to obtain a 2 mm-thick slab of mid-coronal dentin. The occlusal surface of each slab was polished by SiC paper (P600) for 10 s. Then an half part of dentin slabs was randomly selected for receiving treatment with 2.94 μm Er:YAG laser (DEKA, Smart 2940D Plus) with 10 Hz at 100 mJ, pulse duration of 230 μs with contact tip. Dentin slabs were randomly divided into four groups (n = 10). Six conical frustum-shaped build-ups were constructed on the occlusal surface of each dentin slab using bonding agents (OptiBond Solo Plus Group 1;OptiBond All-in-one Group 2) combined with a resin composite (Premise Flow), self-adhesive resin composites (Vertise Flow Group 3) and a glass-ionomer cement (Ketac-Fil Group 4). Specimens were subjected to μSBS test. Data were analyzed by a mixed model and Tukey’s test. Results: Measured bond strengths were (mean ± standard deviation): 20.8 ± 5.5 MPa (laser treatment) and 15.6 ± 4.5 MPa (SiC paper) for Group 1, 18.9 ± 5.3 MPa (laser treatment) and 14.0 ± 4.3 MPa (SiC paper) for Group 2, 7.9 ± 2.8 MPa (laser treatment) and 4.3 ± 2.2 MPa (SiC paper) for Group 3, 4.7 ± 1.9 MPa (laser treatment) and 2.6 ± 1.2 MPa (SiC paper) for Group 4. The inferential analysis showed that the dentin laser treatment significantly affected the bond strength within each individual group. On dentin treated with laser the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Similarly, on dentin treated with SiC paper the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Conclusion: Er:YAG laser treatment has increased the shear bond strength of all the adhesive materials used.展开更多
This study examined the adhesive strength of two self-adhesive methacrylate resin-based sealers（MetaSEAL and RealSeal SE） to root dentin and compared them with RealSeal and AH Plus in properties. A total of 48 extra...This study examined the adhesive strength of two self-adhesive methacrylate resin-based sealers（MetaSEAL and RealSeal SE） to root dentin and compared them with RealSeal and AH Plus in properties. A total of 48 extracted human single-rooted teeth were used to prepare the 0.9-mm thick longitudinal tooth slice（each per tooth）. Standardized simulated canal spaces of uniform dimensions were prepared in the middle of radicular dentin. After treated with 5.25% sodium hypochlorite（NaOCl） and 17% EDTA, tooth slices were allocated randomly to four groups（n=12） in terms of different sealers used： MetaSEAL, RealSeal SE, RealSeal, and AH plus groups. The simulated canal spaces were obturated with different sealers in each group. There were 10 slabs with 20 simulated canal spaces（n=20） used in each group for push-out testing. The failure modes and the ultrastructures of fractured sealer-dentin interfaces were examined. The remaining 2 slabs in each group underwent partial demineralization for observation of the ultrastructure of resin tags. The results showed that the push-out bond strength was 12.01±4.66 MPa in MetaSEAL group, significantly higher than that in the other three groups（P0.05）. Moreover, no statistically significant differences were noted in the push-out bond strength between RealSeal SE（5.43±3.68 MPa） and AH Plus（7.34±2.83 MPa） groups and between RealSeal SE and RealSeal（2.93±1.76 MPa） groups（P0.05）. Mixed failures were predominant in the fractured sealer-dentin interfaces in MetaSEAL and AH Plus groups, while adhesive failures were frequently seen in RealSeal SE and RealSeal groups. In conclusion, after complete removal of the smear layer, MetaSEAL showed superior bond ability to root dentin. The RealSeal SE is applicable in clinical practice, with its adhesive strength similar to that of AH Plus. The self-adhesive methacrylate resin-based sealer holds promise for use in endodontic treatment.展开更多
The aim of this pilot study was to evaluate the shear bond strength of superficial bovine incisor dentin in different crown regions. Bonding was performed to the incisal, middle and cervical thirds of superficial bovi...The aim of this pilot study was to evaluate the shear bond strength of superficial bovine incisor dentin in different crown regions. Bonding was performed to the incisal, middle and cervical thirds of superficial bovine coronal dentin (n = 20) with a two-step etch-and-rinse adhesive (Optibond Solo Plus) and resin composite (Z100). Shear bond strength was evaluated at 24 h and failure modes of representative specimens wereobserved with FE-SEM. Non-parametric Kruskal-Wallis test with a significance level of 0.05 was used for data analysis. Mean shear bond strength values for the incisal, middle, and cervical thirds were 36.9 (3.1), 42.6 (2.6), and 37.1 (2.1) respectively with no significant differences evidenced between the crown thirds (p = 0.19). Observation of the failure mode of representative specimens demonstrated that specimens with high bond strength values exhibited predominantly mixed-type failures whereas low strength specimens exhibited adhesive failures between the dentin and adhesive. The absence of significant differences in shear bond strength between crown thirds indicate that, regardless of tubule orientation, any crown region can be used when superficial bovine incisor dentin is used for shear bond strength testing.展开更多
The effect of different types of surface preparation with SiC abrasive paper on the shear bond strength (SBS) of superficial bovine dentin obtained from the incisal, middle and cervical thirds were evaluated. Dentin s...The effect of different types of surface preparation with SiC abrasive paper on the shear bond strength (SBS) of superficial bovine dentin obtained from the incisal, middle and cervical thirds were evaluated. Dentin substrates were obtained with twenty specimens for each locationgrit combination. Superficial dentin was exposed and prepared to 120-, 320-, or 600-grit SiC;the dentin surfaces were treated with Optibond Solo Plus (Kerr) and polymerized for 20 s. The specimens were placed in a jig, filled with resin composite Z100 (3M-ESPE), polymerized for 40 s according to manufacturer’s instructions, and stored for 24 h at 37℃ and 100% humidity. After 24 h, SBS was measured using a loading testing machine (Ul-tradent) and expressed in megapascals. A two-way ANOVA and Tukey test were used for data analysis. No statistically significant effect of the location (P = 0.254) or interaction grit-location (P = 0.629) were observed on SBS. Statistically significant effect of the grit on the SBS was detected (P < 0.001) with 320-grit being statistically different from 600-grit (P = 0.011) and 120-grit (P < 0.001). No significant differences were observed between 600-grit and 120-grit (P = 0.413). Regardless of the location, 320-grit consistently showed the lowest SBS indicating that different surface grit preparations have an effect on dentin SBS values.展开更多
目的研究牙本质表面不同湿润度及酸蚀对2种通用型粘接剂——Single Bond Universal(SBU)、Prime Bond Universal(PBU)粘接强度的影响。方法选取60颗人新鲜无龋磨牙,随机均分为6组,制备出一个矩形的平坦、光滑的牙本质粘接面,每个粘接面...目的研究牙本质表面不同湿润度及酸蚀对2种通用型粘接剂——Single Bond Universal(SBU)、Prime Bond Universal(PBU)粘接强度的影响。方法选取60颗人新鲜无龋磨牙,随机均分为6组,制备出一个矩形的平坦、光滑的牙本质粘接面,每个粘接面被均分为两部分,一侧进行酸蚀处理,另一侧不进行酸蚀处理,利用蒸馏水移液器制备出干燥、湿润和过湿的牙本质表面,分别用SBU和PBU进行粘接。树脂固化后垂直于牙本质表面切割出1 mm×1 mm的柱形小棒,在万能测试仪上测试其微剪切粘接强度;采用体视显微镜观察界面断裂模式,并在扫描电子显微镜下观察各组树脂-牙本质粘接界面形态。每两组间采用独立样本t检验进行统计学分析(P<0.05)。结果(1)酸蚀模式、粘接剂、湿润度三种因素均有统计学意义。(2)在酸蚀组,无论是SBU还是PBU,3种湿度牙本质表面的粘接强度差异无统计学意义(P>0.05);在未酸蚀组,SBU在干燥牙本质表面的粘接强度明显低于在湿润和过湿牙本质表面的粘接强度,差异有统计学意义(P<0.05),PBU在未酸蚀的3种不同湿度牙本质表面的粘接强度差异无统计学意义(P>0.05)。(3)SBU酸蚀各组比对应的未酸蚀各组能获得更高的粘接强度,但在湿润和过湿条件下,酸蚀与否差异无统计学意义(P>0.05);PBU酸蚀各组比对应的未酸蚀各组能获得更高的粘接强度,差异均有统计学意义(P<0.05)。(4)SBU与PBU相比,同等实验条件下能获得更高的粘接强度,但在酸蚀后的湿润、过湿牙本质表面,SBU和PBU粘接强度差异无统计学意义(P>0.05)。(5)断裂模式均以界面断裂为主,无显著性差异。(6)扫描电镜观察结果显示:两种粘接剂在酸蚀条件下形成的树脂突更密集、更长,并且有树脂突伸入牙本质小管中。未酸蚀条件下,两种粘接剂形成的树脂突均较稀疏和短小,SBU比PBU形成的树脂突相对较多。结论(1)SBU应用于酸蚀后的牙本质表面对水分的敏感性较低,PBU应用于酸蚀或未酸蚀的牙本质表面对水分的敏感性均较低;(2)SBU和PBU应用于酸蚀后的牙本质表面比未酸蚀的牙本质表面能获得更高的粘接强度。展开更多
Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries,reversible pulpitis or traumatic pulp exposure.The presence of bacteria on the cavity walls or in the pulp was the major factor th...Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries,reversible pulpitis or traumatic pulp exposure.The presence of bacteria on the cavity walls or in the pulp was the major factor that leads to the failure of pulp capping.Traditional pulp capping agent,calcium hydroxide,may not prevent microleakage.Selfetching system is a newly developed adhesive system,which could provide less microleakage and would not break down or dissolve,preventing the oral fluids and bacteria from the pulp along the cavity wall.This may reduce such clinical problems as postoperative sensitivity,secondary caries and marginal discoloration.Researches showed that some kinds of self-etching adhesives induced the mild to moderate inflammatory pulp response,with negative bacterial staining.Inclusion of antibacterial components into self-etching system,such as 12-methacryloyloxydodecylpyridinium bromide(MDPB)may inhibit bacteria and provide better clinical effects.It is speculated that using the self-etching adhesive system containing the antibacterial agent,such as MDPB,to the dental pulp directly or indirectly,may inhibit bacteria after the placement of restoration as well as residual bacteria in the cavity.展开更多
目的:观察牙本质黏结界面微渗漏与纳米渗漏,探讨两者的关系。方法:在离体人磨牙的颊、舌侧颈部制备盒形单面洞(直径3mm,洞深2mm),将牙分为2组,每组5个牙。对2组牙的窝洞分别应用黏结剂Single Bond、Clearfil SE Bond,然后充填复合树脂...目的:观察牙本质黏结界面微渗漏与纳米渗漏,探讨两者的关系。方法:在离体人磨牙的颊、舌侧颈部制备盒形单面洞(直径3mm,洞深2mm),将牙分为2组,每组5个牙。对2组牙的窝洞分别应用黏结剂Single Bond、Clearfil SE Bond,然后充填复合树脂并光照固化。所有牙齿进行冷热循环5000次,之后在牙齿表面涂指甲油。将牙齿浸泡于500g/L氨化硝酸银液(pH8.0)中,24h后再浸泡于显影液中8h。随后将牙纵向剖开,暴露充填物剖面,在体视显微、扫描电镜下观察剖面充填物龈缘渗漏情况。结果:所有牙剖面修复体龈缘均存在程度不同的微渗漏,有微渗漏的黏结界面处并未发现因黏结原因所造成的裂缝或微裂隙,但在混合层内观察到纳米渗漏。结论:牙本质黏结界面的微渗漏染色不一定因界面裂缝所致,界面无裂缝的纳米渗漏同样可造成微渗漏染色。展开更多
文摘Objective To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.Methods Twelve caries-free human primary molars were randomly divided into 2 groups with 6 teeth each.In group 1,each tooth was hemisected into two halves.One half was assigned to control subgroup 1,which was bonded with a single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 1 in which the adhesive was applied three times before light curing.In group 2,the teeth were also hemisected into two halves.One half was assigned to control subgroup 2,which was bonded with the single-step self-etching adhesive according to the manufacturer's instructions;the other half was assigned to experimental subgroup 2 in which three layers of adhesive were applied with light curing each successive layer.Microtensile bond strength was immediately tested after specimen preparation.Results When the adhesive was applied three times before light curing,the bond strength of the experimental subgroup 1(n=33,57.49±11.61 MPa) was higher than that of the control subgroup 1(n=31,49.71±11.43 MPa,P<0.05).When using the technique of applying multiple layers of adhesive with light curing each successive layer,no difference of immediate bond strength was observed between the control subgroup 2 and the experimental subgroup 2(P>0.05).Conclusion Multiple coatings of one-step self-etching adhesive can increase the immediate bond strength to primary dentin when using the technique of light-curing after applying three layers of adhesive.
文摘Objective To investigate whether multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin. Methods Twelve caries-free human primary molars were randomly divided into 2 groups. In group 1, each tooth was hemisected into 2 halves. One half was assigned to the control subgroup 1, which was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instruc- tions; the other half was assigned to experimental subgroup 1, in which the adhesive was applied three times before light curing. In group 2, one split half tooth was bonded with a commercially available one-step self-etching adhesive according to the manufacturer＇s instructions; for the other half, three layers of adhesive were applied with each successive layer of light curing. Specimens were stored in 0.9% NaC1 containing 0.02% sodium azide at 37℃ for 18 months and then were subjected to microtensile bond strength test and the fracture mode analysis. Results When the adhesive was applied three times before light curing, the bond strength of the ex- perimental subgroup 1 was significantly higher than that of the control subgroup 1 （47.46__＋13.91 vs. 38.12＋11.21 MPa, P〈O.05）. When using the technique of applying multiple layers of adhesive with each successive layer of light curing, no difference was observed in bond strength between the control subgroup and the experimental subgroup （39.40＋8.87 vs. 40.87-＋9.33 MPa, P〉O.05）. Conclusion Multiple coatings can improve the bond durability of one-step self-etching adhesive to primary dentin when using the technique of light-curing after applying 3 layers of adhesive.
文摘The purpose of this study was to evaluate the influence of acid etching on the bond strength of a universal adhesive system (Single Bond Universal, 3M) to caries-affected dentin. Forty permanent third molars were selected and carious lesions were induced by the microbiological method with?S. mutans?ATCC25175. Teeth were allocated randomly across four experimental designs (n?=?10): PA-I: phosphoric acid etching and application of the adhesive system, followed by immediate microtensile bond strength testing;PA-CC: phosphoric acid etching and application of the adhesive system, followed by microtensile bond strength testing after a 14-day cariogenic challenge;NPA-I: application of the adhesive system without acid etching, followed by immediate bond strength testing and NPA-CC: application of the adhesive system without acid etching followed by bond strength testing after 14-day cariogenic challenge. For microtensile bond strength testing,?a restoration with Charisma composite resin was made and each specimen was sectioned with a cross-sectional area of 1 mm2. Only adhesive and mixed fractures were considered for bond strength calculation. Results were evaluated by the Kruskal-Wallis and Friedman tests. The highest bond strengths were observed in the phosphoric acid etching groups (p??0.05). Cariogenic challenge did not affect bond strength (p?>?0.05). The predominant fracture type was adhesive. We conclude that phosphoric acid increased the bond strength of the Single Bond Universal system to caries-affected dentin, and that cariogenic challenge did not interfere with this bond strength.
文摘Background: To date there is not a material considered ideal for the lased dentin. Objective: To compare the bond strength to human lased dentin of self-etch and etch-and-rinse adhesive systems, a self-adhesive resin composite and a glass-ionomer cement. Methods: Forty human molars were sectioned to obtain a 2 mm-thick slab of mid-coronal dentin. The occlusal surface of each slab was polished by SiC paper (P600) for 10 s. Then an half part of dentin slabs was randomly selected for receiving treatment with 2.94 μm Er:YAG laser (DEKA, Smart 2940D Plus) with 10 Hz at 100 mJ, pulse duration of 230 μs with contact tip. Dentin slabs were randomly divided into four groups (n = 10). Six conical frustum-shaped build-ups were constructed on the occlusal surface of each dentin slab using bonding agents (OptiBond Solo Plus Group 1;OptiBond All-in-one Group 2) combined with a resin composite (Premise Flow), self-adhesive resin composites (Vertise Flow Group 3) and a glass-ionomer cement (Ketac-Fil Group 4). Specimens were subjected to μSBS test. Data were analyzed by a mixed model and Tukey’s test. Results: Measured bond strengths were (mean ± standard deviation): 20.8 ± 5.5 MPa (laser treatment) and 15.6 ± 4.5 MPa (SiC paper) for Group 1, 18.9 ± 5.3 MPa (laser treatment) and 14.0 ± 4.3 MPa (SiC paper) for Group 2, 7.9 ± 2.8 MPa (laser treatment) and 4.3 ± 2.2 MPa (SiC paper) for Group 3, 4.7 ± 1.9 MPa (laser treatment) and 2.6 ± 1.2 MPa (SiC paper) for Group 4. The inferential analysis showed that the dentin laser treatment significantly affected the bond strength within each individual group. On dentin treated with laser the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Similarly, on dentin treated with SiC paper the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Conclusion: Er:YAG laser treatment has increased the shear bond strength of all the adhesive materials used.
文摘This study examined the adhesive strength of two self-adhesive methacrylate resin-based sealers（MetaSEAL and RealSeal SE） to root dentin and compared them with RealSeal and AH Plus in properties. A total of 48 extracted human single-rooted teeth were used to prepare the 0.9-mm thick longitudinal tooth slice（each per tooth）. Standardized simulated canal spaces of uniform dimensions were prepared in the middle of radicular dentin. After treated with 5.25% sodium hypochlorite（NaOCl） and 17% EDTA, tooth slices were allocated randomly to four groups（n=12） in terms of different sealers used： MetaSEAL, RealSeal SE, RealSeal, and AH plus groups. The simulated canal spaces were obturated with different sealers in each group. There were 10 slabs with 20 simulated canal spaces（n=20） used in each group for push-out testing. The failure modes and the ultrastructures of fractured sealer-dentin interfaces were examined. The remaining 2 slabs in each group underwent partial demineralization for observation of the ultrastructure of resin tags. The results showed that the push-out bond strength was 12.01±4.66 MPa in MetaSEAL group, significantly higher than that in the other three groups（P0.05）. Moreover, no statistically significant differences were noted in the push-out bond strength between RealSeal SE（5.43±3.68 MPa） and AH Plus（7.34±2.83 MPa） groups and between RealSeal SE and RealSeal（2.93±1.76 MPa） groups（P0.05）. Mixed failures were predominant in the fractured sealer-dentin interfaces in MetaSEAL and AH Plus groups, while adhesive failures were frequently seen in RealSeal SE and RealSeal groups. In conclusion, after complete removal of the smear layer, MetaSEAL showed superior bond ability to root dentin. The RealSeal SE is applicable in clinical practice, with its adhesive strength similar to that of AH Plus. The self-adhesive methacrylate resin-based sealer holds promise for use in endodontic treatment.
文摘粪肠球菌是难治性根尖周炎(refractory apical periodontitis,RAP)的主要致病菌,该细菌可耐受严苛环境,引发根尖周免疫炎症反应,造成根管内外持续性感染。粪肠球菌黏附于根管牙本质壁形成生物膜,其耐药和抗冲刷能力显著增强,是介导其致病的关键因素。粪肠球菌与牙本质的黏附包括非特异性和特异性黏附,后者由黏附相关毒力因子介导,主要包括肠球菌胶原结合蛋白(adhesin of collagen from enterococci,Ace)、表面蛋白(extracellular surface protein,Esp)、明胶酶(gelatinase,GelE)和丝氨酸蛋白酶(serine prtease,SprE)、菌毛以及聚集物质,且受到多个双组份系统调控。Fsr双组份系统在群体密度增加时可以促进gelE及sprE的表达,GelE进一步减少表面肠球菌胶原结合蛋白Ace,而GrvRS双组份系统则在响应血清环境时直接下调ace的表达。CroRS双组份系统及WalRK双组份系统也可能分别促进和抑制包括ace及gelE在内的多种毒力因子的表达,进而影响粪肠球菌的黏附性。此外,根管机械/化学预备、根管内环境因素等均可对粪肠球菌牙本质黏附产生影响。根管治疗中避免粪肠球菌的引入和使用干扰黏附的药物可以有效预防粪肠球菌的黏附,而多种活化荡洗方法也可以有效增加根管内粪肠球菌的清除率。针对粪肠球菌牙本质黏附关键因子与调控因素为靶点设计合理药物,有望为根管感染控制提供新的思路与手段。本文就粪肠球菌与牙本质的黏附性及其影响因素进行综述。
文摘The aim of this pilot study was to evaluate the shear bond strength of superficial bovine incisor dentin in different crown regions. Bonding was performed to the incisal, middle and cervical thirds of superficial bovine coronal dentin (n = 20) with a two-step etch-and-rinse adhesive (Optibond Solo Plus) and resin composite (Z100). Shear bond strength was evaluated at 24 h and failure modes of representative specimens wereobserved with FE-SEM. Non-parametric Kruskal-Wallis test with a significance level of 0.05 was used for data analysis. Mean shear bond strength values for the incisal, middle, and cervical thirds were 36.9 (3.1), 42.6 (2.6), and 37.1 (2.1) respectively with no significant differences evidenced between the crown thirds (p = 0.19). Observation of the failure mode of representative specimens demonstrated that specimens with high bond strength values exhibited predominantly mixed-type failures whereas low strength specimens exhibited adhesive failures between the dentin and adhesive. The absence of significant differences in shear bond strength between crown thirds indicate that, regardless of tubule orientation, any crown region can be used when superficial bovine incisor dentin is used for shear bond strength testing.
文摘The effect of different types of surface preparation with SiC abrasive paper on the shear bond strength (SBS) of superficial bovine dentin obtained from the incisal, middle and cervical thirds were evaluated. Dentin substrates were obtained with twenty specimens for each locationgrit combination. Superficial dentin was exposed and prepared to 120-, 320-, or 600-grit SiC;the dentin surfaces were treated with Optibond Solo Plus (Kerr) and polymerized for 20 s. The specimens were placed in a jig, filled with resin composite Z100 (3M-ESPE), polymerized for 40 s according to manufacturer’s instructions, and stored for 24 h at 37℃ and 100% humidity. After 24 h, SBS was measured using a loading testing machine (Ul-tradent) and expressed in megapascals. A two-way ANOVA and Tukey test were used for data analysis. No statistically significant effect of the location (P = 0.254) or interaction grit-location (P = 0.629) were observed on SBS. Statistically significant effect of the grit on the SBS was detected (P < 0.001) with 320-grit being statistically different from 600-grit (P = 0.011) and 120-grit (P < 0.001). No significant differences were observed between 600-grit and 120-grit (P = 0.413). Regardless of the location, 320-grit consistently showed the lowest SBS indicating that different surface grit preparations have an effect on dentin SBS values.
文摘目的研究牙本质表面不同湿润度及酸蚀对2种通用型粘接剂——Single Bond Universal(SBU)、Prime Bond Universal(PBU)粘接强度的影响。方法选取60颗人新鲜无龋磨牙,随机均分为6组,制备出一个矩形的平坦、光滑的牙本质粘接面,每个粘接面被均分为两部分,一侧进行酸蚀处理,另一侧不进行酸蚀处理,利用蒸馏水移液器制备出干燥、湿润和过湿的牙本质表面,分别用SBU和PBU进行粘接。树脂固化后垂直于牙本质表面切割出1 mm×1 mm的柱形小棒,在万能测试仪上测试其微剪切粘接强度;采用体视显微镜观察界面断裂模式,并在扫描电子显微镜下观察各组树脂-牙本质粘接界面形态。每两组间采用独立样本t检验进行统计学分析(P<0.05)。结果(1)酸蚀模式、粘接剂、湿润度三种因素均有统计学意义。(2)在酸蚀组,无论是SBU还是PBU,3种湿度牙本质表面的粘接强度差异无统计学意义(P>0.05);在未酸蚀组,SBU在干燥牙本质表面的粘接强度明显低于在湿润和过湿牙本质表面的粘接强度,差异有统计学意义(P<0.05),PBU在未酸蚀的3种不同湿度牙本质表面的粘接强度差异无统计学意义(P>0.05)。(3)SBU酸蚀各组比对应的未酸蚀各组能获得更高的粘接强度,但在湿润和过湿条件下,酸蚀与否差异无统计学意义(P>0.05);PBU酸蚀各组比对应的未酸蚀各组能获得更高的粘接强度,差异均有统计学意义(P<0.05)。(4)SBU与PBU相比,同等实验条件下能获得更高的粘接强度,但在酸蚀后的湿润、过湿牙本质表面,SBU和PBU粘接强度差异无统计学意义(P>0.05)。(5)断裂模式均以界面断裂为主,无显著性差异。(6)扫描电镜观察结果显示:两种粘接剂在酸蚀条件下形成的树脂突更密集、更长,并且有树脂突伸入牙本质小管中。未酸蚀条件下,两种粘接剂形成的树脂突均较稀疏和短小,SBU比PBU形成的树脂突相对较多。结论(1)SBU应用于酸蚀后的牙本质表面对水分的敏感性较低,PBU应用于酸蚀或未酸蚀的牙本质表面对水分的敏感性均较低;(2)SBU和PBU应用于酸蚀后的牙本质表面比未酸蚀的牙本质表面能获得更高的粘接强度。
文摘Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries,reversible pulpitis or traumatic pulp exposure.The presence of bacteria on the cavity walls or in the pulp was the major factor that leads to the failure of pulp capping.Traditional pulp capping agent,calcium hydroxide,may not prevent microleakage.Selfetching system is a newly developed adhesive system,which could provide less microleakage and would not break down or dissolve,preventing the oral fluids and bacteria from the pulp along the cavity wall.This may reduce such clinical problems as postoperative sensitivity,secondary caries and marginal discoloration.Researches showed that some kinds of self-etching adhesives induced the mild to moderate inflammatory pulp response,with negative bacterial staining.Inclusion of antibacterial components into self-etching system,such as 12-methacryloyloxydodecylpyridinium bromide(MDPB)may inhibit bacteria and provide better clinical effects.It is speculated that using the self-etching adhesive system containing the antibacterial agent,such as MDPB,to the dental pulp directly or indirectly,may inhibit bacteria after the placement of restoration as well as residual bacteria in the cavity.
文摘目的:观察牙本质黏结界面微渗漏与纳米渗漏,探讨两者的关系。方法:在离体人磨牙的颊、舌侧颈部制备盒形单面洞(直径3mm,洞深2mm),将牙分为2组,每组5个牙。对2组牙的窝洞分别应用黏结剂Single Bond、Clearfil SE Bond,然后充填复合树脂并光照固化。所有牙齿进行冷热循环5000次,之后在牙齿表面涂指甲油。将牙齿浸泡于500g/L氨化硝酸银液(pH8.0)中,24h后再浸泡于显影液中8h。随后将牙纵向剖开,暴露充填物剖面,在体视显微、扫描电镜下观察剖面充填物龈缘渗漏情况。结果:所有牙剖面修复体龈缘均存在程度不同的微渗漏,有微渗漏的黏结界面处并未发现因黏结原因所造成的裂缝或微裂隙,但在混合层内观察到纳米渗漏。结论:牙本质黏结界面的微渗漏染色不一定因界面裂缝所致,界面无裂缝的纳米渗漏同样可造成微渗漏染色。
