通过龋的易感性探讨牙釉质脱矿和再矿化的影响因素

龋病的发生过程取决于牙釉质脱矿和再矿化之间的平衡。研究表明,最近几年波兰地区儿童和青少年的龋病发生率较高且较严重,说明针对儿童和青少年的龋病预防有待加强。本实验目的是,①针对龋病的易感性对不同牙齿和牙面进行分析;②评估牙釉质脱     

Nd:YAG激光照射对釉质表面微硬度的影响

目前,龋病仍然是儿童和青少年中最常见的疾病。在防龋的研究中发现,Nd:YAG激光照射后可提高牙釉质表面的抗酸性,但其对牙釉质表面微硬度影响的意见不一致,部分研究结果显示Nd:YAG激光可提高牙釉质表面的微硬度,但也有报道Nd:     

牙釉质龋中的蛋白溶解现象

作者从三个方面探讨牙釉质龋病变中的蛋白溶解现象。首先观察了木瓜酶、胰蛋白酶及胶原酶对人工龋形成及活体人牙釉质脱矿的影响,实验结果表明:此三种酶对两者均无明显作用。进一步用菌斑液处理人牙釉质粉,再进行脱矿实验,也未发现菌斑液有促进人牙质粉脱矿的作用。结果提示在牙釉质龋病变中,蛋白溶解现象不是主要的。     

氟化物在龋病预防中的作用

本文概述了最近关于氟化物防龋作用的研究,并将这些机制应用于解释龋病预防的实践。由于龋病开始于菌斑—牙釉质临界面,因而在讨论氟化物的防龋作用时,最好从两方面入手:一种是作用于牙釉质的化学结构和形态的机制;一种是作用于菌斑的机制。氟化物对牙釉质的作用(1)氟化物与牙釉质溶解度最早并且到目前尚在流行的一种最广泛     

电子探针测定乳牙釉质氟元素及其与龋病的关系

目的:探讨乳牙釉质氟元素的分布及其与龋病状况之间的关系.方法:用电子探针显微分析仪测量35个离体的下颌乳中切牙唇舌面之不同深度的牙釉质氟含量,比较分析无龋组与有龋组牙釉质氟含量及其与龋病状况之间的关系.结果:乳牙釉质氟含量在唇舌侧分布相似,由表层到内层氟含量呈递减趋势;无龋组和有龋组之间牙釉质氟含量无统计学差异;牙釉质氟含量与龋补牙数(dft)和龋蚀指数(CSI)无相关性.结论:氟元素含量在乳牙釉质不同深度具有差异,其含量与龋病程度无关.     

釉质仿生再矿化的研究进展与挑战

龋病为全球发病率最高的疾病(35％,2010 年)?[1].因此,早期预防和治疗牙釉质龋将节省大量治疗费用和医疗资源,尤其是针对治疗不配合的幼儿和残障人士、行动不便的老年人,甚至也包括较长时间在外执行任务的航天员、军队士兵等特殊人群,或在口腔医生职业暴露风险提高的公共卫生事件中,不便开展有创治疗时,亟需一种快速高效地恢复天然/类天然牙釉质硬组织的仿生再矿化方法.本文拟从仿生角度浅谈釉质发生过程与釉质仿生矿化之间的相互关系,为早期牙釉质龋病的预防和微创治疗提供一条新的研究思?路.     

牙釉质显微硬度测定在龋病研究中的应用

牙釉质显微硬度是用显微压痕技术测得的釉质硬度,它对测定釉质早期脱矿时矿物质的变化有高灵敏性,作为研究釉质龋的指标之一,在龋病的病因、预防及治疗等方面的研究上均有重要意义。本文对牙釉质显微硬度的测定在龋病研究中的作用进行回顾和总结。     

牙釉质显微硬度测定在龋病研究中的应用

牙釉质显微硬度是用显微压痕技术测得的釉质硬度,它对测定釉质早期脱矿时矿物质的变化有 高灵敏性,作为研究釉质龋的指标之一,在龋病的病因、预防及治疗等方面的研究上均有重要意义。本文对牙釉质显微硬度的测定在龋病研究中的作用进行回顾和总结。     

口腔内科学：龋病及牙体硬组织非龋性疾病

护牙素在固定矫治术中对牙釉质脱矿的应用研究,Carisolv技术治疗乳牙龋病的临床应用评价，乳牙Carisolv去龋的扫描电镜观察,应用Carisolv（伢典）凝胶去腐技术治疗乳牙龋病的临床观察,     

牙釉质的成分

研究牙釉质的化学结构对龋病的研究有密切关系。只有了解牙釉质内部的系统的化学变化及其对龋患率的可能影响,才能阐明龋病的发病机制。牙釉质内含大量的仅在电子显微镜下可以看到的无机物质—结晶体。这些结晶体中主要有与磷灰石相似的磷酸钙;还可能有一些低钙磷灰石的结构以及一些非磷灰石的结晶。牙釉质矿物中含钙、磷酸及氢氧离子组成氢氧磷灰石。事实上有些氢氧离子始终未被结合以致能不断加速化学反应,而另一部分可以被氟所取代,钙和磷酸离子亦会被取     

低出生体重儿和早产儿乳牙釉质发育缺陷与龋齿易感性的研究

目的从临床和实验研究两方面探讨乳牙釉质发育缺陷与龋齿易感性的关系。方法选择１７６例３～８岁的低出生体重儿和早产儿，分析乳牙釉质发育缺陷与龋齿的相关性；将４颗自然脱落的釉质发育不全乳前牙用于釉质溶解度的研究，比较发育不全部位和正常部位釉粉的溶解度。结果临床研究发现乳牙釉质发育缺陷与龋齿的发生显著相关；乳牙釉质混浊和釉质发育不全分别与龋齿的发生显著相关。溶解度研究发现发育不全的釉质溶解度大，且达到平衡的时间短。结论釉质发育缺陷（釉质发育不全和釉质混浊）增加了牙齿对龋的易感性     

Caries incidence and lesion progression from adolescence to young adulthood: a prospective 15-year cohort study in Sweden

The objectives were (1) to assess caries development, including the incidence and rate of lesion progression, in a Swedish cohort from adolescence to young adulthood and (2) to compare the caries incidence rates in adolescents with those of young adults. The original material consisted of 536 children aged 11-13 years at baseline. This cohort had been followed through annual bitewing radiographs to 21-22 years of age. In 1998-1999, 250 of these individuals were re-examined at the age of 26-27, and the new caries data were added to the original data. The results showed that fewer new enamel lesions developed on approximal surfaces during young adulthood than during adolescence; the caries incidence rates for enamel lesions decreased from 4.3 in the age group 12-15 years to 2.7 new caries lesions/100 surface-years in the age group 20-27 years. The same applied to the rate of lesion progression, where the corresponding values from the enamel-dentin border to the outer dentin were 32.5 for the youngest and 10.9 new lesions/100 surface-years for the oldest age group. The caries incidence of outer dentin lesions on approximal surfaces was low but increased from 0.2 in the age group 12-15 years to 0.9 new outer dentin lesions/100 surface-years in the age group 20-27 years. The incidence rates varied considerably between different tooth surfaces. Also for occlusal surfaces, fewer new dentin lesions developed during young adulthood than during adolescence; the incidence was 2.0 new dentin lesions/100 surface-years in the youngest age group and 0.7 during young adulthood. At the age of 13, the proportion of DFS of occlusal surfaces predominated over DFS of approximal surfaces but at the age of 26-27 the proportions of occlusal and approximal DFS were almost equal.     

The prevalence of caries and enamel defects in 229 Malaysian children 16 years after water fluoridation (a pilot study)

Two hundred and twenty-nine children aged 12-15 years who were continuous residents of Penang island, in the north of Peninsular Malaysia were examined for caries and enamel defects. Caries prevalence was 82.2% with a DMFT score of 3.4 and DMFS score of 4.9; there were very few missing teeth and very little untreated caries in the population examined. Majority of DF (decayed/filled) lesions were pits and fissures with approximal and smooth surfaces relatively caries free. The prevalence of enamel defects was 76.4% with 19.1% of all teeth examined being affected. More posterior than anterior teeth were affected by enamel defects just as there were more maxillary than mandibular teeth affected by enamel defects. Diffuse patchy opacities were the most common defect diagnosed and this was found in 60.2% of the population examined. A bilateral distribution of diffuse patchy opacities was seen in 41.5% of the population examined. Tooth surfaces with enamel defects were no more susceptible to caries than defect-free surfaces.     

早产儿乳牙釉质发育缺陷及患龋状况的临床研究

目的研究早产儿乳牙釉质发育缺陷及龋病的发病率,并探讨两者的相关关系。方法选取3～7岁早产儿及足月出生儿两组各173名,进行乳牙釉质发育缺陷及患龋情况的调查统计和数据对比分析。结果早产儿组釉质发育缺陷(DDE)的患病率(63.58%)明显高于正常出生组DDE的患病率(34.10%),其患病率男女性别间无明显差异。DDE好发于上颌切牙。早产儿组的患龋率(69.36%)与正常出生组的患龋率(71.68%)无明显差异。结论早产儿的乳牙釉质发育缺陷率较高,做好早产儿的口腔保健及父母的口腔健康知识教育是非常重要的。     

武汉市6～8岁儿童龋病及第一恒磨牙窝沟形态调查研究

目的调查武汉市6～8岁儿童龋病和第一恒磨牙窝沟形态情况,为儿童患龋风险评估和龋病预防政策的制定提供理论依据。方法选取武汉市区5所小学二年级学生,共检查1043名儿童,平均年龄7.6岁。由两名口腔医师检查龋病和第一恒磨牙窝沟形态。其中,龋指数采用改良世界卫生组织标准,使用单因素方差分析和t检验进行统计学分析。结果恒牙D3水平的患龋率为8.7%,乳牙d3水平的患龋率为68.7%。恒牙龋均和龋面均分别为0.11和0.14,乳牙龋均和龋面均分别为2.8和5.0。其中乳牙龋指数d3占d3mft的73.6%,而乳牙早期釉质龋牙数占乳牙d2水平牙数的36.4%。中窝沟和深窝沟第一恒磨牙的儿童占总受检人数的84.6%。结论武汉市6～8岁儿童的乳牙患龋率高,第一恒磨牙中度和深度窝沟比例较高,因此应对高患龋风险的儿童进行窝沟封闭等预防措施。     

乳牙釉质混浊的偏光特点及其与龋齿易感性的研究

目的 从临床和实验研究两方面探讨乳牙釉质混浊对龋齿的易感性。方法 选择176名3-8岁的低出生体重儿和早产儿，分析乳牙釉质混浊与龋齿的相关性；将5颗自然脱落的釉质混浊乳前牙用于偏光显微镜的研究，发现其组织学特点，并探讨乳牙釉质混浊的发生机制。结果 临床研究发现乳牙釉质混浊与龋齿的发生显著相关；进一步的偏光显微镜研究的发现乳牙釉质混浊为表层下矿化缺陷，且矿化缺陷区域釉柱横纹加重。结论 乳牙釉质混浊因其表层下矿化缺陷增加了牙齿对龋的易感性，乳牙釉质混浊其发生为在牙齿矿化阶段的第三矿化期的中晚期出现全身或局紊乱所致。     

Proteolytic phenomenon in enamel caries]

The proteolytic phenomenon in enamel caries has been investigated from three directions.Three kinds of proteolytic enzymes,papain,trypsin and collagenase have been used for treating enamel both in vitro and in vivo to observe their effect on the development of artificial enamel caries and demineralization of upper central incisors of thirty young persons.The results showed that the depth of the artificial caries was not increased after enzyme treatment.The calcium content of the demineralizing solution is also not increased after enzyme treatment.when the enamel powder of human beings was treated at first by natural plaque fluid and then by demineralizing liquid,no difference was observed between the data of experimental and control groups.Therefore,the results of this study does not support Gottleib's proteolytid theory of caries,especially in case of enamel ones.     

恒磨牙窝沟釉质表面结构扫描电镜观察

目的观察未萌牙、初萌牙、成年牙咬合面窝沟和光滑面釉质表面的超微结构,比较窝沟釉质表面在萌出前后不同时期的变化。方法用激光龋齿检测仪和显微放射照相法确定咬合面窝沟无龋损的未萌牙6颗、初萌牙7颗、成年牙5颗为研究样本。劈开窝沟,对其窝沟釉质壁的表面及颊面釉质进行扫描电镜观察。结果①未萌牙窝沟侧壁釉质表面可见明显的釉质横纹,釉柱末端凹陷明显并分布有大量的微孔和灶性孔,类似蜂窝状,与颊面釉质表面无明显差别。②初萌牙窝沟侧壁釉质表面表现与未萌牙基本一致,颊面微孔减少。③成年牙窝沟侧壁上部釉质表面可见明显的表浅凹陷,可见少量的微孔,表面较光滑,较致密;窝沟下部的釉质表面结构较疏松,存在较多的微孔和灶性孔,呈蜂窝状结构,与未萌牙相似。结论在未萌牙、初萌牙、成年牙窝沟侧壁下部存在多孔状釉质发育缺陷。成年牙窝沟上部的釉质表面结构接近其颊面,与窝沟底部相比有较大差别,提示窝沟上部釉质在牙萌出后出现修复现象。     

老年恒牙、年轻恒牙及乳牙釉质磨损性能的体外对比研究

目的探讨并比较各个年龄组人牙釉质磨损行为的异同.方法采用老年恒牙、年轻恒牙及乳牙各8个釉质样本,经体外模拟摩擦试验测得其磨损量,通过测量硬度和断裂韧性以及分析磨斑形貌和釉质中Ca、P、Si元素含量等揭示釉质的摩擦磨损机制.结果老年恒牙、年轻恒牙、乳牙牙釉质磨损量分别为(2.40±1.10)×10-12 m3、(3.50±1.83)×10-12 m3、(4.86±2.49)×10-12 m3,其中老年恒牙磨损明显小于乳牙(P＜0.05),年轻恒牙与乳牙、老年恒牙与年轻恒牙磨损量间差异无显著性(P＞0.05),但三者在机械性能和磨损特征方面均有所不同.结论各年龄组人牙釉质与陶瓷牙对摩时,主要发生磨粒磨损和断裂磨损,各类牙釉质超微结构的差异决定了其抗磨性能的不同.人牙釉质的硬度和断裂韧性测量值与磨损量无对应关系.