牙齿漂白对金属托槽粘结强度的影响

目的:研究牙齿漂白对正畸托槽粘结强度的影响。方法:选取于中山大学孙逸仙纪念医院口腔正畸科就诊的患者60例,将患者分为未漂白组、漂白后即刻粘结组及漂白24h后粘结组,6个月后对三组的脱落率进行比较,结果:三组间差异具有统计学意义(P0.05)。未漂白组的脱落率明显低于另外两组(P0.05),即刻粘结组的脱落率明显高于其他两组(P0.05)。结论:漂白对托槽的粘结有不利影响,其中以即刻粘结最为显著。     

酸蚀时间对牙本质粘结强度的影响

目的：研究比较不同酸蚀时间对4种全酸蚀粘结剂（OptiBond Solo（OB）、Single Bond（SB）、One—Step（OS）、Prime＆BondNT（PB））牙本质粘结强度的影响。方法：选取32颗无龋坏人磨牙，用600目碳化硅砂纸在流水冲洗下预备出统一的牙本质粘结面玷污层，分别选用4种粘结剂在不同粘结面酸蚀时间条件下进行粘结处理；每颗牙齿垂直于粘结面切割出8个（1．0×1．0×4．0）mm^3粘结试件，分别进行微拉伸强度（μTBS）测试。结果：4种粘结剂OB（25．36±4．18）MPa、SB（24．25±3．97）MPa、OS（28．65±4．93）MPa和PB（27．12±4．13）MPa在酸蚀粘结面15S时均取得了最高的牙本质粘结强度（P〈0．01）。结论：不同酸蚀时间对不同粘结剂牙本质粘结强度的影响不同。     

过氧化脲漂白剂对牙齿颜色影响的实验研究

目的：研究不同增稠载体及浓度的过氧化脲（carbamide peroxide,CP）漂白剂对牙齿颜色的影响。方法：以卡波姆（carbopol）、聚乙烯吡咯烷酮（PVP）或泊洛沙姆（Poloxamer）为漂白剂的增稠载体,分别配制含有10％和20％CP的漂白凝胶。将60颗离体变色牙随机分为6组,每组10颗。1组牙冠用以Carbopol为增稠载体的10％CP凝胶漂白;2组牙冠用以Carbopol为增稠载体的20％CP凝胶漂白;3组牙冠用以PVP为增稠载体的10％CP凝胶漂白：4组牙冠用以PVP为增稠载体的20％CP凝胶漂白;5组牙冠用以Poloxamer为增稠载体的10％CP凝胶漂白;6组牙冠用以Poloxamer为增稠载体的20％CP凝胶漂白。各组在37℃、100％湿度条件下每天漂白6～8h,持续2周。分别在漂白前、漂白后1周和2周对牙冠的L＊a＊b＊值进行测定,并计算色差（△E）,漂白前后自身对照。结果：以Carbopol为增稠载体,20％CP漂白2周组的漂白效果最明显（P〈0．01）;以PVP或Poloxamer为增稠载体的各组分析结果同Carbopol组。不同增稠载体的10％CP或20％CP漂白1周和2周,漂白效果没有显著差异（P〉0．05）。结论：同种增稠载体下,20％CP的漂白效果明显优于10％CP,漂白时间越长,漂白效果越明显;不同增稠载体对漂白效果没有影响。     

粘结面润湿度对牙本质粘结强度的影响

目的：研究、比较不同粘结面润湿度对4种粘结剂（OptiBond Solo（OB）、Single Bond（SB）、One-Step（OS）、Prime＆Bond NT（PB））牙本质粘结强度的影响。方法：选取36颗无龋坏人磨牙，用600目碳化硅砂纸在流水冲洗下预备出统一的牙本质粘结面玷污层。分别用4种全酸蚀粘结剂在不同粘结面润湿度条件下进行粘结处理。每颗牙齿垂直于粘结面切割出8个1.0mm×1.0mm×4.0mm粘结试件，分别进行微拉伸强度（μTBS）测试。结果：4种粘结剂OB（25.24±2.07）MPa、SB（24.28±4.73）MPa、OS（28.29±4.35）MPa和PB（26.87±4.39）MPa在润湿的牙本质粘结面上均取得了最高的牙本质粘结强度（P〈0.01）。结论：不同粘结面润湿度对不同溶剂粘结剂牙本质粘结强度的影响不同。     

Opalescence PF家庭美白系统牙齿漂白的临床效果评价

目的：评价Opalescence PF家庭美白系统漂白牙齿的临床效果。方法：随机选取80名着色牙病例,并分为生理性黄牙、氟斑牙、四环素牙及变色死髓牙4个组,用Opalescence PF家庭美白系统进行牙齿漂白,以VITA比色板分析脱色效果,用数字化疼痛评判法记录受试者术中牙齿的敏感度,半年后复查评价疗效稳定性。结果：①Opalescence PF家庭美白系统漂白疗效总有效率为100%,除氟斑牙组漂白显效率高于四环素牙组（P〈0.05）,其余几组间漂白显效率均无统计学差异（P〉0.05）;②除死髓牙组,术中各组部分患者有不同程度的牙齿酸痛症状,但停止用药后2～3h均能缓解;氟斑牙组重度敏感率为21.1%;③术后半年漂白疗效总有效率各组间无统计学差异（P〉0.05）;4组患者术后半年漂白疗效的总有效率与治疗结束时无统计学差异。结论：Opalescence PF家庭美白系统治疗着色牙效果显著并具有一定的稳定性。     

过氧化脲漂白剂对光固化树脂修复体颜色影响的实验研究

目的：研究不同增稠载体与不同过氧化脲（carbamide peroxide，CP）浓度配制的漂白剂对光固化复合树脂修复体颜色的影响.方法：分别以卡波姆（carbop0l）和聚乙烯吡咯烷酮（PVP）作为漂白剂的增稠载体，以11%和15%的CP作为漂白活性成分，配制漂白剂.用四种临床常用的复合树脂：Spectrum TPH（Dent sply），Chari sma（Kulzer），Dyract AP（Dentsply）和F2000（3M）制作圆片状修复体，分别用含不同增稠载体和浓度的CP漂白剂在37℃、1 00%湿度条件下漂白6～8h/天，持续2周，漂白前后对试件的L＊a＊b＊值进行测定，计算色差（△E）.结果：Spectrum和Charisma组，F2000和Dyract组漂白前后的△E没有显著差异（P＞0.05），而Spectrum和Charisma组漂白前后的△E分别和F2000组、Dyract组比较均有显著差异（P＜0.05）;四种复合树脂经不同载体和浓度CP漂白处理后的△E和对照组相比P值均＞0.05，没有统计学差异.结论：不同载体和浓度的CP漂白剂可以引起光固化复合树脂颜色的改变，但没有显著的临床意义.为避免树脂充填材料和周围牙齿颜色的不匹配以及继发龋的发生，建议漂白治疗后重新更换修复体.     

“劲润”牙本质保护膜的牙本质粘结性能探讨

目的：探讨“劲润”牙本质保护膜（Hybrid Coat,HyC）的牙本质粘结性能。方法：选取A组（HyC）和其他3组不同类型的牙本质粘结剂：B组（G-Bond）、C组（MegaBond）和D组（single Bond）,比较其对牛牙牙本质的剪切粘结强度,并用实体显微镜观察粘结界面断裂模式。各组试料数分别为n=10,结果通过Tukey-Kramer（P〈0．05）进行统计学分析。结果：B、C、D组均显示了较大的粘结强度,3组之间无统计学差异。A组（HyC）显示了较低的粘结强度,约10．08MPa,与其他3组之间存在显著性差异。断裂模式显示,A组（HyC）以界面破坏为主,而其他3组以凝集破坏和混合破坏为主。结论：本研究结果提示,“劲润”牙本质保护膜（HyC）的粘结强度弱于其他3组牙本质粘结剂。为了保证HyC长期稳定的防过敏效果及粘结性能,在今后的研究中有必要进一步探讨如何提高HyC的牙本质粘结性能。     

正畸托槽不同粘结方法的粘结强度比较

目的:比较托槽间接粘结法同直接粘结法的托槽粘结强度差异。方法:收集96颗因正畸拔除的新鲜人类前磨牙,随机分为A、B和C三组,每组32颗。A组使用改良间接粘结法,B组选用Sondhi推荐的间接粘结法,C组采用直接粘结法。分别检测两组粘结剂残留和托槽的抗剪切强度。结果:3组粘结剂残留存在统计学差异(Z=19.35,P0.05),C组残留率最多,进一步两两比较,A组比B组粘结剂残留较少,但差异不具有统计学意义(t=1.25,P0.05);3组抗剪切强度存在统计学差异(F=7.493,P0.05);进一步两两比较,A组(9.92±3.51)与B组(9.38±2.09)抗剪切强度无统计学差异(P0.05),C组(12.41±4.09)抗剪切强度强于A和B组,且差异有统计学意义(P0.05)。结论:改良间接粘结法与Sondhi法相比,粘结剂残留率较低,抗剪切强度较高,能够满足临床需要。     

过氧化脲漂白剂对釉质粘结强度的影响

目的：评价不同载体、不同浓度过氧化脲（Car bami de Per oxi de,CP）漂白剂对粘结釉质强度的影响。方法：60颗离体磨牙随机分为7组。1～6组颊舌面分别用以卡波姆（Carbopol）、聚乙烯吡咯烷酮（PVP）、泊洛沙姆（Pol oxamer）为增稠载体的含100g/L CP、200g/L CP的漂白剂在37℃、100%湿度条件下每天漂白8h,其中部分样本再浸入10%的抗坏血酸钠凝胶中3h,持续2周后即刻粘结树脂或延迟2周粘结。7组为对照组。准备界面为1mm×1mm的条形试件。通过微拉伸法测试釉质粘结强度,对不同类型的断面进行扫描电镜（scanni ng el ect i on mi croscope,SEM）观察。利用Spss11.0软件通过双因素方差分析（Two-way anal ysi s of var i ance）和SNK-q检验对其微拉伸粘结强度（iM cr ot ensi l e bond st r engt h,MTBS）进行统计分析。结果：各实验组2周漂白后即刻粘结,釉质粘结强度明显低于对照组（P〈0.05）;10%CP漂白同时抗氧化治疗或延迟粘结,釉质的粘结强度和对照组没有明显差异（P〉0.05）;20%CP漂白同时抗氧化治疗或延迟粘结,可明显提高釉质的粘结强度（P〈0.05）,但和对照组仍有显著差异（P〈0.05）。同种载体下,经10%CP漂白后的釉质粘结强度高于20%CP漂白组（P〈0.05）。同种浓度下,不同增稠载体组间的粘结强度没有显著差异（P〉0.05）。结论：漂白后即刻粘结,釉质的粘结强度随CP浓度的增高而下降;延迟2周粘结或抗氧化治疗可从一定程度上提高釉质的粘结强度,缩短漂白后粘结的时间;增稠载体对釉质的粘结强度没有显著影响。     

TREE牙齿脱色凝胶用于活髓牙夜间漂白的疗效观察

目的:观察TREE牙齿脱色凝胶用于活髓牙夜间漂白的治疗效果。方法:选择不同原因引起的着色牙患者48例,应用TREE牙齿脱色凝胶进行活髓牙夜间漂白治疗,依据临床检查和患者自评相结合进行疗效判定。结果:所有患者用药一周后牙齿均有改善。48例中27人疗效满意,21人牙齿色泽改善。治疗中16人(33.3%)出现副作用。结论:TREE牙齿脱色凝胶用于活髓牙夜间漂白使用方便、安全、有效且对牙周组织有益。     

Tensile bond strength of a flowable composite resin to ER:YAG-laser-treated dentin

BACKGROUND AND OBJECTIVES: This in vitro study evaluated the influence of a flowable composite resin (FCR) on the tensile bond strength of resin to dentin treated with the Er:YAG Laser (L) and diamond bur (DB). STUDY DESIGN/MATERIALS AND METHODS: Ninety dentin surfaces obtained from 45 third molars were ground and randomly divided into six groups (n = 15): G1-DB, G2-DB+FCR, G3-L (100 mJ, 10 Hz, 37.04 J/cm2), G4-L (100 mJ, 10 Hz, 37.04 J/cm2)+FCR, G5-L (250 mJ, 2 Hz, 92.60 J/cm2), and G6-L (250 mJ, 2 Hz, 92.60 J/cm2)+FCR. After surface etching with 37% phosphoric acid and the application of an adhesive system, inverted conical specimens were prepared with a hybrid composite resin. In groups G2, G4, and G6 a FCR was placed before the hybrid composite resin. After 24 hours-storage in distilled water, the tensile test was performed in a universal testing machine (0.5 mm/minute, 500 N). RESULTS: Data were submitted to Kruskal Wallis test (P = 0.01). The mean bond strength values (MPa+/-SD) were: G1-13.54 (+/-2.99), G2-14.67 (+/-2.32), G3-9.49 (+/-3.09), G4-14.60 (+/-2.76), G5-8.97 (+/-3.89), and G6-13.02 (+/-2.18). Groups G1 and G2 presented the highest bond strength values, which were statistically similar to those of G4 and G6. The groups treated with laser and without the FCR (G3 and G5) showed the lowest shear bond strength values. CONCLUSIONS: FCR can increase the adhesion to dentin treated with Er:YAG laser within different parameters.     

Shear bond strength of composite bonded to erbium:yttrium-aluminum-garnet laser-prepared dentin

The purpose of this study was to evaluate the dentin bond strength to resin composite following erbium:yttrium-aluminum-garnet (Er:YAG) laser preparation using different adhesive systems. Seventy dentin specimens prepared from human molar teeth were randomly assigned to seven groups of ten. The first five groups were prepared with an Er:YAG laser 2940 nm at the manufacturer’s recommended settings and (1) acid etched, and etch-and-rinse adhesive Excite was applied; (2) Excite was applied; (3) two-step self-etching adhesive AdheSE was applied; (4) laser etched (120 mJ/10 Hz), and Excite was applied; (5) laser etched, and AdheSE was applied. The last two groups were added as controls (prepared with a diamond bur): (6) acid etched, and Excite was applied; (7) AdheSE was applied. Nanohybrid composite cylinders 4 mm × 2 mm were bonded to the dentin surfaces. After the specimens had been stored in distilled water and had undergone thermocycling, the shear bond strength was tested and the data were analyzed statistically. The Duncan multiple comparison test showed that specimens prepared with a diamond bur and with acid and Excite applied showed the highest mean bond strength (13.01 ± 2.09 MPa), followed by those prepared with Er:YAG and with AdheSE applied (11.5 ± 3.59 MPa) and those prepared with a diamond bur and with AdheSE applied (10.75 ± 1.95 MPa), but there were no significant differences among them (P > 0.05). Er:YAG-prepared specimens, with acid, Excite (3.28 ± 0.95 MPa) and specimens that were laser etched and with AdheSE applied (3.37 ± 0.63 MPa) showed the lowest mean values for bond strength (P < 0.05). The results suggested that dentin surfaces prepared with Er:YAG laser may provide comparable composite resin bond strengths depending on the adhesives used.     

15%过氧化脲漂白无髓变色牙的临床效果评价

目的：评价15%过氧化脲漂白无髓变色牙的治疗效果。方法：对89例（97颗）无髓变色、牙冠完整的前牙根据牙齿变色的时间分成A组（变色2年之内）、B组（变色2～5年）、和C组（变色5年以上）,均使用15%过氧化脲进行诊间和夜间漂白相结合、冠内和冠外联合漂白治疗,应用Spss17.0软件包对所得到的数据进行统计学分析。结果：总有效率91.75%,其中A组有效率100%,B组有效率94.59%,而C组有效率仅为66.67%。A、B两组牙齿治疗提高的色阶数值的差异没有统计学意义。结论：15%过氧化脲进行诊间和夜间漂白相结合、冠内和冠外联合漂白能有效地治疗无髓变色牙。     

Effect of Er:YAG laser on bond strength to dentin of a self-etching primer and two single-bottle adhesive systems

BACKGROUND AND OBJECTIVES: To assess the effect of erbium:yttrium aluminium garnet (Er:YAG) laser on bond strength to dentin of a self-etching primer (Clearfil Liner Bond 2V, CL2V) and two single-bottle agents (Excite, EX; Gluma One Bond, GB). STUDY DESIGN/MATERIALS AND METHODS: Thirty human molars were selected, roots were removed and crowns were bisected, providing 60 halves. Specimens were included and ground to expose dentin. Bonding site was limited and samples were assigned to three groups: I, CL2V; II, EX; III, GB. Dentin was either conventionally treated or submitted to laser conditioning + conventional treatment. The adhesive protocol was performed, samples were stored for 24 hours and bond strength was tested to failure (0.5 mm/min). RESULTS: Statistical analysis showed a decrease in bond strength for lased subgroups and this drop was more evident for EX. CL2V provided the best overall results, regardless of the surface treatment. CONCLUSIONS: Er:YAG laser may adversely affect bond strength in higher or lesser degree, depending on the adhesive system used.     

Shear bond strength of self-etching adhesive systems to Er:YAG-laser-prepared dentin

This study was conducted to compare the shear bond strengths of composite resin bonded to Er:YAG laser or bur-prepared dentin surfaces using three self-etching adhesive systems. The occlusal surfaces of 120 human third molars were ground flat to expose dentin. The dentin was prepared using either a carbide bur or an Er:YAG laser at 350 mJ/pulse and 10 Hz (fluence, 44.5 J/cm²). Three different self-etching adhesive systems were applied: iBond™, Xeno III™ and Clearfil SE Bond™. Rods of composite resin were bonded to dentin surfaces and shear bond tests were carried out. Both dentin surfaces after debonding and resin rods were observed using a scanning electron microscope. When the Xeno III™ was used, no difference was observed on shear bond strength values when bur and Er:YAG laser were compared. When using iBond™ and Clearfil SE Bond™, bond strength values measured on Er:YAG-laser-prepared surfaces were lower than those observed on bur-prepared surfaces. The absence of smear layer formation during the preparation of the dentin by the Er:YAG laser did not improve the adhesion values of self-etching adhesive systems.     

无髓变色牙内漂白术的临床疗效观察

目的：本文介绍使用无髓变色牙内漂白术的安全性及临床疗效观察研究。方法：漂白治疗前,必须拍摄X线片确认根管已做过完善根充。髓腔内置入30%过氧化氢棉球暂封1周。复诊3～6次达到正常色泽后用复合树脂进行充填,3年后复查。结果：74例患者,痊愈56例,占75.7%,好转15例,占20.3%,有效率达96%,失败3例,占4%。结论：采用髓腔内置入30%过氧化氢溶液治疗无髓变色牙方法能获得较好的长期临床疗效。     

联合偶联剂表面处理对金属托槽与不同瓷修复体黏结强度影响的研究

目的:研究四种表面处理方法对三种陶瓷修复体表面处理后与金属托槽间黏结强度的影响。方法:三种不同的瓷粉制作试件并随机分成四个处理组:①酸蚀;②喷砂;③喷砂+偶联剂;④酸蚀+偶联剂。在各组试件表面处理后黏结金属托槽并测量其黏结剪切强度。结果:①经统计学分析,无论对于喷砂还是酸蚀,结合硅烷偶联剂处理后都能显著地提高托槽与瓷修复体表面的黏结强度(P<0.05);而且这种经偶联剂辅助处理后黏结强度提高的特点,是不因为瓷修复体的材料的不同而有显著的差异性的(P>0.05);②酸蚀不同于喷砂,单独处理时达不到临床托槽黏结强度要求,而结合硅烷偶联剂后,其黏结强度有显著的提高(P<0.05);③同一处理方法对不同的陶瓷修复体其黏结剪切强度无统计学差异(P>0.05)。结论:偶联剂作为一种辅助处理措施,可以提高喷砂或酸蚀处理后托槽与瓷修复体表面的黏结强度;联合硅烷偶联剂处理,可使单独应用达不到临床托槽黏结要求的酸蚀表面处理方法,达到临床应用要求。