资源描述:
《组合酸不同酸蚀时间对氟斑牙正畸托槽粘接强度的影响》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、天津医药2008年5月第36卷第5期351组合酸不同酸蚀时间对氟斑牙正畸托槽粘接强度的影响△张疆弢刘建国徐宇红江策丰雷黄瑾摘要目的:观察组合酸不同酸蚀时间对新鲜离体氟斑牙牙釉质超微结构的影响,寻找增强氟斑牙托槽粘接强度的方法。方法:选择5颗正常恒牙,用37%的磷酸酸蚀作为对照组。将中、重度氟斑牙25颗随机分为5组,用同一组合酸进行酸蚀,时间分别为1、2、3、4和5min,酸蚀后粘接托槽,24h后测定托槽的抗剪切强度,并通过扫描电镜观察去除托槽后树脂-牙釉质界面形态学改变。结果:对照组抗剪切强度为(3.
2、33±2.03)MPa,氟斑牙酸蚀时间1~5min组抗剪切强度分别为(7.81±1.04)MPa,(10.71±2.96)MPa,(5.87±2.70)MPa,(4.02±1.86)MPa,(4.05±2.27)MPa。除氟斑牙酸蚀2min组与对照组比较差异无统计学意义(P>0.05),其余各组与对照组比较差异均有统计学意义(P<0.05)。除氟斑牙酸蚀1min时牙釉质超微结构改变不明显,酸蚀2min时有较明显的蜂窝状改变,随酸蚀时间延长釉质结构溶解破坏增多。结论:组合酸酸蚀氟斑牙2min可获得较理想
3、的粘接强度和形态变化。关键词氟中毒,牙酸蚀,牙正畸学牙釉质抗剪切强度TheInfluencesofDifferentEtchingTimewithComoseAcidonShearBondStrengthofOrthodonticBondinginFluoroticHumanEnamelZHANGJiangtao,LIUJianguo,XUYuhong,JIANGCe,FENGLei,HUANGJinStomatologicalHospitalofZunyiMedicalUniversity,Zuny
4、i563003,ChinaAbstractObjective:Toevaluatebondingstrengthoforthodonticbracketbondedtofluoroticteethinvitrobyusingdifferentetchingtimesandinvestigatetheeffectsofdifferentetchingtimesonthemicromorphologyofenameltofindamethodtoincreasebondingstrengthofortho
5、donticbracketbondedtofluoroticteeth.Methods:Fivenormalteethand25fluoroticteeth,freshlyextractedfrompatients,wereincludedinthestudy.Controlgroupoffivenormalteethwaserodedby37%phosphoricacidfor1min.Allofthefluoroticteethwererandomlydividedinto5groups.Each
6、groupof5teethwaserodedfor1min,2min,3min,4min,5minwithcomoseacid.Afteretching,bracketswerebondedwithacompositeresin.Shearbondstrengthwasmeasured24hourslater.Thentheetchingpatternsofenamelwereobservedbyscanningelectronmicroscope(SEM).Results:Theshearbonds
7、trengthofthenormalteethwas(3.33±2.03)MPa.Thevaluesofshearbondstrengthindifferentfluoroticteethgroupsfrom1minto5minwere(7.81±1.04),(10.71±2.96),(5.87±2.70),(4.02±1.86)and(4.05±2.27)MParespectively.Thereweresignificantdifferencesinbondstrengthbetweeneacho
8、fthefluoroticteethgroupsandcontrolgroup(P<0.05)exceptforthefluoroticteethgroupofetching2min(P>0.05).TherewerenosignificantSEMchangesinfluoroticteethwith1minerodedbutobvioushoneycombwasappearedin2mingroup.Theerosionofenamelbecamem