自酸蚀偶联剂不同作用时间对托槽与牙面剪切粘接强度影响的研究

目的测量自酸蚀偶联剂不同作用时间下托槽与牙面间剪切粘接强度,以探讨正畸临床上运用自酸蚀偶联剂粘接托槽的最佳作用时间.方法选择48颗正畸减数的恒双尖牙,随机分为四组,自酸蚀偶联剂作用时间分别为5秒、15秒、30秒和60秒.所有样本均用光固化粘接剂粘接托槽.半小时后测量四组的剪切粘接强度(Shear bond strength,SBS)及粘接剂残留指数(Adhesive remnant index,ARI),并通过扫描电子显微镜观察树脂-牙釉质界面形态学改变.结果四组托槽与牙面平均剪切粘接强度范围5.1609 Mpa～5.5146 Mpa,组间剪切粘接强度无显著性差异(p＞0.05);ARI评分表明自酸蚀偶联剂作用时间为60秒时,牙面上残留的粘接剂明显多于其他三组;电镜观察结果显示随着自酸蚀偶联剂作用时间的延长,树脂突的形态更规则,结构更致密.结论自酸蚀偶联剂作用时间在5～60秒范围内较厂家推荐时间延长或缩短均不会影响其剪切粘接强度.     

两种正畸粘接系统对金属和陶瓷托槽粘接强度的影响

目的:评价传统正畸粘接系统和自酸蚀粘接系统分别对金属托槽和陶瓷托槽的粘接强度。方法:将100颗人前磨牙均分为4组:金属托槽/传统粘接系统组(1组)、金属托槽/自酸蚀粘接系统组(2组)、陶瓷托槽/传统粘接系统组(3组)、陶瓷托槽/自酸蚀粘接系统组(4组),使用Transbond XT树脂糊剂将托槽粘接在牙面上,测量各组的抗剪切粘接强度,并评价其剩余粘接剂指数,对结果进行单因素方差分析。结果:统计学分析表明金属托槽的抗剪切粘接强度高于陶瓷托槽,其差异具有统计学意义(P<0.05);1组和2组平均抗剪切粘接强度的差异无统计学意义(P>0.05),3组和4组间的差异也无统计学意义(P>0.05);各组剩余粘接剂指数的差异无统计学意义(P>0.05),但各组的粘接强度与剩余粘接剂指数有平行相关性(P<0.05)。结论:金属托槽的粘接强度高于陶瓷托槽;自酸蚀粘接系统与传统粘接系统都可满足正畸临床粘接托槽的需求;大部分样本的粘接失败发生在托槽/粘接剂界面或粘接剂内部破坏,表明牙釉质受损的几率较低,且粘接强度和剩余粘接剂指数之间存在统计学相关性。     

金属托槽与瓷面粘接强度的实验研究

目的研究瓷面处理对金属托槽与瓷面粘接强度的影响。方法180个烤瓷试件按不同瓷面处理随机分3组：氧化铝喷砂组；金刚砂车针打磨组；9．6％氢氟酸（HF）酸蚀组。再根据是否使用硅烷偶联剂及粘接剂不同分为4组，每组15个试件。粘接剂为京津釉质粘接剂及3M UniteTM粘接剂。托槽粘接后检测抗剪切强度。结果不同处理方式，使用偶联剂前后平均抗剪切强度均有统计学意义（P〈0．05）。结论瓷面经处理后使用硅烷偶联剂粘接托槽，可达到满意的粘结强度。     

3种酸蚀、粘接方法粘接托槽后釉质粘接剂界面的超微形态观察

目的研究不同粘接材料、不同酸蚀方法粘接正畸金属托槽后釉质粘接剂界面纵切面的超微形态。方法选择正畸拔除的健康前磨牙72颗,随机分成3组,每组24颗。A组用体积分数37%的磷酸酸蚀30 s,京津釉质粘接剂粘接金属托槽;B组用体积分数37%的磷酸酸蚀30 s,Transbond光固化粘接剂粘接托槽;C组用自酸蚀处理液加压涂抹3 s,Transbond光固化粘接剂粘接托槽。高倍立体显微镜及扫描电镜观察3组牙釉质粘接剂界面纵切面的形态。结果 A组界面紧密而均匀,粘接剂固化后形成的颗粒较大,颗粒之间间隙明显。B组界面紧密均匀,粘接剂固化后的颗粒较小而均匀,颗粒间结合紧密。C组界面疏松不均匀,树脂突少而细,有时可见较明显的裂隙。结论不同酸蚀、粘接方法牙釉质粘接剂界面的结合情况不同,磷酸酸蚀组釉质表面与粘接剂间形成的树脂突较均匀而密合,而自酸蚀组多处存在较大的裂隙,提示酸蚀方法可能是影响微渗漏的主要原因。     

两种托槽粘接剂的比较实验和研究

目的：测定树脂和化学固化型玻璃离子托槽粘接剂的抗剪切粘接强度。方法：100颗离体双尖牙被随机分成两组，每组又按照测试时间的不同分成3个亚组。组1、组2分别用京津釉质粘合剂(树脂)、Ketac—Bond(化学固化型玻璃离子粘接结剂)粘接托槽，对所有实验样本进行了抗剪切粘接强度的测试。结果：①树脂和化学固化型玻璃离子的抗剪切粘接强度随时间的增加而增强。②树脂粘接剂的断裂主要发生在釉质—树脂界面，而化学固化型玻璃离子粘接剂的断裂则主要发生在自身内部。结论：树脂型托槽粘接剂固化后24h以内达到临床应用标准，而化学固化型玻璃离子粘接剂在固化后24h以内达不到该标准，不适合于临床应用。     

喷磨预处理对离体氟斑牙正畸托槽粘接强度的影响

目的筛选一种使氟斑牙与托槽有较高粘接强度的临床可行的粘接方法。方法选择15例氟斑牙正畸患者拔除的60颗第一前磨牙为研究对象,采用随机区组设计方法分为15个区组,每区组包括每位患者的4颗牙齿,区组内采用随机排列表法分为A、B、C、D 4小组,每小组即包括每位患者的1颗牙齿,共计15颗。4小组采用不同方法粘接托槽,分别为常规酸蚀后用釉质粘接剂粘接、喷磨预处理后用釉质粘接剂粘接、自酸蚀后用Bond粘接剂和光固化复合树脂粘接、喷磨预处理和自酸蚀后用树脂粘接剂和光固化复合树脂粘接;然后测定4小组的粘接强度和托槽底面粘接剂的余留情况。结果A、B、C、D 4小组的托槽/牙面剪切强度测试结果分别为（2.247±0.261）MPa、（5.374±0.469）MPa、（4.345±0.401）MPa、（5.791±0.636）MPa,4组间存在统计学差异（P<0.01）,D组剪切强度最大,其次为B、C组,A组最小。4组样本在去除托槽时残留粘接剂的情况无统计学差异（P>0.05）。结论氟斑牙面先用空气喷磨机喷磨,然后进行自酸蚀和树脂粘接托槽是一种较为可行的方法。     

金属托槽与瓷面粘接去除后瓷破损率的比较研究

目的:研究瓷面处理及硅烷偶联剂对金属托槽与瓷面粘接去除后瓷破损率的影响。方法:300个烤瓷试件按不同瓷面处理随机分5组,A组:喷砂3s;B组:金刚砂车针打磨;C组:9.6%氢氟酸酸蚀3min。D组:37%磷酸酸蚀1min;E组:未处理组。再根据是否使用硅烷偶联剂及粘接剂不同分4组,每组15个试件。粘接剂为京津釉质粘接剂及3MUniteTM粘接剂。托槽粘接后检测抗剪切强度,记录瓷破裂指数(PFI)及瓷破损率。结果:使用偶联剂前后PFI有统计学意义(P<0.05),不同处理方式各组间PFI有统计学意义(P<0.05)。结论:瓷面处理及硅烷偶联剂的使用增加了粘接强度,同时增加了瓷面受损的机率。     

不同粘接剂对烤瓷瓷面与金属托槽间剪切强度影响的体外研究

目的 研究不同粘接剂对烤瓷瓷面与金属托槽间剪切强度的影响.方法 40个烤瓷瓷面经打磨、氢氟酸酸蚀、冲洗干燥、硅烷偶联剂处理瓷面后,再根据使用粘接剂的不同分为A组:光固化复合树脂粘接剂、B组:单组份化学固化复合树脂粘接剂、C组:树脂改良型光固化玻璃离子粘接剂、D组:双组份化学固化复合树脂粘接剂.将40个金属托槽粘接于烤瓷瓷面,经水浴孵化24 h后测得样本剪切强度,并进行统计分析.结果 A组剪切强度大于其他组(P＜0.05),C组剪切强度小于B组(P＜0.05),D组与B、C组剪切强度差异无统计学意义(P＞0.05).结论 光固化复合树脂粘接剂可获得最大的剪切强度,树脂改良型光固化玻璃离子粘接剂对金属托槽与烤瓷瓷面的粘接效果欠佳.     

瓷面处理对金属托槽与瓷面粘接性能的影响

目的　研究瓷表面不同处理方法对金属托槽与瓷修复体的粘接强度及去粘接后瓷面完整性的影响。方 法　根据使用粘接剂和表面处理方法的不同,将80个瓷面随机分为8组,每组10个瓷面。分别用京津釉质粘接剂 和光固化复合树脂粘接,表面处理分别行37%磷酸酸蚀、9·6%氢氟酸酸蚀、打磨去釉、瓷面涂硅烷偶联剂4种表面 处理法。试件粘接托槽后经37℃恒温水浴24 h后测定抗剪切强度,记录去粘接后的瓷面破裂情况。对磷酸酸蚀, 氢氟酸酸蚀、打磨去釉的瓷面进行扫描电镜观察。结果　采用氢氟酸酸蚀、打磨去釉、硅烷偶联剂组的粘接抗剪切 强度明显高于磷酸酸蚀组(P<0·01)。打磨去釉后用光固化复合树脂粘接及氢氟酸酸蚀或瓷表面涂硅烷处理后使 用任意一种粘接材料粘接均取得有效的粘接强度。各组去粘接后的瓷破裂率无显著性差异(P>0·05)。结论　氢 氟酸酸蚀、打磨去釉、瓷面涂硅烷偶联剂均可以明显增加金属托槽与瓷面之间的粘接抗剪切强度。瓷面涂硅烷偶 联剂是金属托槽与瓷面粘接时良好的表面处理剂。     

不同正畸粘接系统在托槽再粘接中的应用评价

目的：检测使用不同正畸粘接系统再粘接托槽对其剪切粘接强度的影响,以探讨提高临床再粘接效率的方法。方法：选择60颗正畸减数的恒双尖牙,依据不同粘接系统随机分为3组：津京釉质粘接剂（A组）、TransbondXT光固化粘接系统（B组）及Transbond自酸蚀粘接系统（C组）。所有样本均先用津京釉质粘接剂粘接托槽,24h后去除托槽重新粘接新托槽,测量3组托槽再粘接的剪切强度及粘接剂残留指数（AdhesiveRemnantIndex,ARI）。结果：3组托槽再粘接剪切强度分别为（8．615±2．460）MPa、（8．807±1．801）MPa及（8．144±3．023）MPa,组间剪切强度差异无显著性;ARI评分表明：C组牙面上残留的粘接剂明显少于其他两组。结论：采用自酸蚀粘接系统再粘接托槽的剪切强度与其它两种粘接系统相当,并且去除托槽后牙面残留粘接剂较少。     

Oral cancer: molecular technologies for risk assessment and diagnosis

Purpose: The effective biomarkers related to diagnosis, metastasis, drug resistance and irradiation sensitivity of oral cancers will help the pathologist and oncologist to determine the molecular taxonomy diagnosis and design the individualization treatment for the patients with oral cancers.     

Stimulated whole saliva components in children with Down syndrome

The authors report on the components of stimulated whole saliva from children with Down syndrome—including pH, flow rate, sialic acid and protein concentrations, and amylase and peroxidase activity. Saliva samples were collected from 35 children aged 6–10 years. Of the participants, 17 had Down syndrome and 18 did not. To stimulate saliva production, the children chewed a piece of parafilm for 10 minutes before the sample was collected. Soon after collecting the saliva sample, the authors measured pH using a portable pH-meter. Sialic acid levels were determined with a thiobarbituric acid assay. Protein content was determined with Folin's phenol reagent. Amylase was assayed and the authors measured the maltose produced by the breakdown of starch and peroxidase using ortho-dianisidine.
No statistically significant difference was observed in levels of sialic acid (free and total) between the two groups. Protein concentration was about 36% higher in the group with Down syndrome. However, the salivary flow rate, pH, and amylase and peroxidase activities were lower among the children with Down syndrome.     

柠檬精油对牙周致病菌抑制作用及其安全性初步研究

目的:探讨柠檬精油对牙周致病菌的体外抗菌活性及对细胞增殖的影响。方法:采用微量液体稀释法测定柠檬精油对Pg、Fn、Aa、Pi的最小抑菌浓度(minimal inhibitory concentration,MIC)及最小杀菌浓度(minimum bactericidal concentration,MBC);以较低浓度的MIC为标准稀释LEO作为实验组,采用MTT法测定柠檬精油对HUVECs的毒性作用,明确抑菌浓度下LEO的安全性。结果:柠檬精油对牙周主要致病菌均有抑菌作用,Pg、Fn、Aa、Pi的MIC分别是9.0 g/L、4.5 g/L、4.5 g/L、9.0 g/L,Aa、Fn的 MBC是9.0 g/L,Pg、Pi的MBC未测得。1/2MIC、1/20MIC浓度的LEO能够抑制人脐静脉内皮细胞的生长,而低于1/200MIC浓度的LEO则对人脐静脉内皮细胞的生长没有影响,其中1/200MIC浓度的LEO作用明显优于0.02%的CHX。结论:体外环境中,柠檬精油对牙周致病菌Pg、Fn、Aa、Pi具有抗菌活性,低浓度应用对机体相对安全。     

Computer-assisted planning for maxillofacial prosthodontic rehabilitation

Computerized tomography (CT) planning and the use of CT derived surgical templates for implant placement have shown promise for restoring function within months after surgical reconstruction of acquired post-oncologic defects.     

牙髓再生的研究现状

目前,根管治疗术在临床上已得到了广泛的应用并成功的保存了患牙,但其仍有许多术后并发症。随着组织工程技术在口腔领域的应用,构建一种组织工程化牙髓进行牙髓-牙本质复合体的再生治疗成为可能。近年来国内外已有很多关于牙髓再生的研究,并且已经取得了一定成果。本文将对目前国内外牙髓再生的研究进展现状作一综述。     

Effect of Pingyangmycin on human venous malformation endothelial cells

Purpose: Venous malformations are common vascular anomalies with a propensity of the head and neck. Intralesional injection of Pingyangmycin (PYM, bleomycin A5 hydrochloride) is a widely used sclerotherapy method for the treatment of venous malformation.     

Clinical and pathological aspects on some odontogenic tumors

Odontogenic tumors constitute a very diverse group of lesions that reflects the complex processes of odontogenesis. Controversies over their classification/subtyping, terminology and diagnosis have been persisted, which has direct bearings on therapeutic and/or prognostic implications.     

Can you be too old for oral implants? An update on ageing and plasticity in the oro‐facial sensorimotor system

This review focuses on the capacity of the brain for plasticity and the utility and efficacy of oral implants in helping to restore oro‐facial sensorimotor functions, especially in elderly patients. The review first outlines the components of the oro‐facial sensorimotor system which encompasses both oro‐facial tissues and a number of brain regions. One such region is the sensorimotor cortex that controls the activity of the numerous oro‐facial skeletal muscles. These muscles are involved in a number of functions including reflexes and the more complex sensorimotor functions of mastication, swallowing and speech. The review outlines the use by the brain of sensory inputs from oro‐facial receptors in order to provide for exquisite sensorimotor control of the activity of the oro‐facial muscles. It highlights the role in this sensorimotor control played by periodontal mechanoreceptors and their sensory inputs to the brain, and how oral implants in concert with the plastic capacity of the brain may, at least in part, compensate for reduced sensorimotor functioning when teeth are lost. It outlines findings of ageing‐related decrements in oro‐facial sensorimotor functions and control. The changes in oro‐facial tissues and the brain that underlie these ageing‐related functional alterations are also considered, along with adaptive and compensatory processes that utilise the brain's capacity for plasticity. The review also notes the evidence t hat rehabilitation that incorporates adjunctive approaches such as sensorimotor training paradigms in addition to oral prostheses such as implants may enhance these processes and help maintain or facilitate recovery of sensorimotor functioning in the elderly.     

Tumor microenvironment in oral cancer: novel approaches for immunotherapy

Squamous cell carcinoma of the head and neck (SCCHN), which arises from the squamous mucosal epithelium of the oral cavity, pharynx and larynx, is a major health problem in the US and other parts of the world, especially in developing countries.