离体牙脱矿及再矿化前后牙色度RGB值的变化

目的:应用数码照相、图像分析及染色技术测定离体牙脱矿及再矿化前后牙色度RGB值的变化.方法:选取无龋健康的上颌乳中切牙36颗,随机分为3组.在所有样本牙唇面中1/3处暴露3mm×4mm的开窗面.用2%亚甲基蓝对样本开窗面染色3min后,数码照相.应用数码图像分析技术测定开窗面牙色度RGB1值;再用32%磷酸凝胶酸蚀开窗面1min后.按上述过程重新染色、拍照,测定牙色度RGB2值;然后将样本置于人工唾液中进行再矿化,按矿化时间平均分为3组(组1、2、3),分别再矿化24h、48h和72h,取出后再染色、拍照、测定RGB3值.应用SNK检验对脱矿及再矿化前后RGB值进行比较分析.结果:组1的RGB1、RGB2、RGB3分别为54.58±12.66、24.32±2.4和29.96±3.32;组2分别为58.71±5.85,25.21±2.84和33.66±4.6;组3分别为60.58±8.10、24.41±2.47和34.59±3.53.3组的RGB1、RGB2、RGB3间两两比较差异均有显著性;3组间的RGB1、RGB2值两两比较差异均无显著性;组1与组2、组3的RGB3值间均有统计学差异,而组2与组3的RGB3无统计学差异.结论:数码照相、图像分析及染色技术相结合,可以识别脱矿及再矿化前后牙色度RGB值的变化,用于脱矿和再矿化的研究.     

运用色度学分析技术对离体乳牙脱矿与再矿化时间的实验研究

目的运用数码照相和色度分析技术观测不同酸蚀时间对离体乳牙釉质脱矿以及再矿化时间的影响,以寻找乳牙合适的脱矿及再矿化时间。方法将60颗离体上颌乳中切牙牙冠唇面开窗包埋。标本随机分为4个处理组,32%的磷酸凝胶分别酸蚀开窗面15s(组1)、30s(组2)、45s(组3)和60s(组4),使开窗面脱矿,再将其置于人工唾液中分别再矿化8h、24h、48h、72h及1周。脱矿后采用2%亚甲基蓝对开窗面进行染色,数码照相,运用图像分析软件对图像进行色度分析,记录色度参数,运用SPSS19.0对实验数据进行统计学分析。结果酸蚀15s后染色,其色度值变化即可被计算机所识别;酸蚀15s再矿化72h、酸蚀30s再矿化48h、酸蚀45s和60s再矿化24h时的色度值与矿化前的色度值相比,差异具有统计学意义,其P值分别为0.01、0.037、0.047和0.011。结论运用色度学技术分析乳牙脱矿与再矿化的时间,提示乳牙釉质最合适的酸蚀时间为15s,再矿化时间为72h。     

奥威尔牙齿脱敏剂对早期牙本质龋再矿化及抑制脱矿作用体外研究

目的:使用激光荧光法对奥威尔牙齿脱敏剂对牙本质早期龋再矿化及抑制脱矿的作用进行评价.方法:对60 颗离体牙标本建立人工龋模型后,随机分为3 组,分别使用奥威尔凝胶、含氟牙膏和蒸馏水处理1 h后酸蚀24 h,以激光荧光诊断仪记录各时点的荧光读数.采用t检验和ANOVA方差分析进行统计分析.结果:奥威尔组和含氟牙膏组再矿化前后荧光读数有显著性差异,奥威尔组的读数显著低于含氟牙膏组.与空白对照组相比,奥威尔组和含氟牙膏组酸蚀后的读数均显著较低,但2 组之间无统计学差异.结论:奥威尔凝胶具有再矿化和抑制脱矿作用,其再矿化作用优于普通含氟牙膏,而抑制脱矿作用与普通含氟牙膏相当.     

酸蚀时间、再矿化时间对乳牙釉质再矿化的影响

目的 本研究采用激光共聚焦显微镜来观测不同酸蚀时间、不同矿化时间对乳牙釉质再矿化的影响。方法 采用随机区组设计,将28枚离体乳切牙的唇面分别开4个窗,随机分到酸蚀30 s、60 s、90 s、120 s 4个处理组中,采用32%磷酸凝胶对标本进行酸蚀处理,而后采用人工唾液进行再矿化,分别于脱矿后、再矿化处理2 h,再矿化处理24 h进行激光共聚焦显微镜扫描,记录其平均荧光量(AF),采用重复测量的方差分析对数据进行分析,显著性水平为0.05。结果 多变量方差分析(MANOVA)结果 显示:再矿化时间、酸蚀时间对再矿化后AF有显著影响(分别F=357.74,P<0.0001;F=51.62,P<0.0001);Bonferroni法多重比较显示:酸蚀时间对再矿化效果影响中,除90 s组与120 s组之间的差异没有显著性,其余各组AF两两比较差异均有显著性;矿化时间对再矿化的影响中,两两比较AF差异均有显著性。结论 在进行乳牙抗酸能力及再矿化潜能检测时,酸蚀时间不可超过60 s,再矿化时间可以为24 h。?     

奥威尔牙齿脱敏剂对抗可乐酸蚀作用研究

目的:评价奥威尔牙齿脱敏剂对乳牙釉质再矿化及抑制脱矿的作用。方法:60颗离体牙随机分为6组(n=10),3组进行再矿化实验,用可乐酸蚀25 h后其中2组分别使用奥威尔凝胶和含氟牙膏处理14次以模拟1周再矿化治疗(2 min×2次/d×7 d),剩余1组置于去离子水中。另外3组进行抑制脱矿实验,先使用奥威尔凝胶、含氟牙膏和去离子水分别处理14次,方法同前,再用可乐酸蚀25 h,以激光龋齿探测仪记录各时点的荧光读数。采用t检验和ANOVA方差分析进行统计分析。结果:再矿化实验前,3组荧光值比较无显著差异(P>0.05);再矿化处理后奥威尔组和含氟牙膏组荧光值均显著降低(P<0.01),奥威尔组的荧光读数显著低于含氟牙膏组(P<0.01),空白对照组荧光值高于其他2组(P<0.01)。抑制脱矿实验酸蚀处理前3组荧光值无显著差异(P>0.05);酸蚀处理后奥威尔组和含氟牙膏组荧光值均低于空白对照组(P<0.01),奥威尔组低于含氟牙膏组。结论:奥威尔凝胶具有再矿化和抑制脱矿作用,其再矿化作用和抑制脱矿作用优于含氟牙膏。     

釉质酸蚀后牙面脱矿与再矿化的扫描电镜观察

目的:观察牙釉质酸蚀后在离体状态下和一段时间内在口腔环境中的结构变化,探讨牙釉质脱矿与再矿化的形态学改变.方法:选择因正畸需要拔除健康第一前磨牙病例10例,40个牙,使用YY0269-1995型酸蚀剂对拟拔除的第一前磨牙颊侧釉质酸蚀60 8,左侧上、下颌第一前磨牙为A组,A组再分为A1、A2组,A1组酸蚀后即刻拔除,制作扫描电镜观察标本,A2组,第一前磨牙酸蚀后即刻拔除,置37℃恒温蒸馏水中浸泡1个月后制作电镜标本观察.右侧上、下颌第一前磨牙为B组,第一前磨牙酸蚀后在口内存留1个月后拔除,用相同的方法进行观察,并比较A、B两组牙釉质形态学变化.结果:A组的牙釉质表面松软,不规则,多孔隙,表面呈蜂窝状改变;B组的牙釉质表面有大量矿物质沉积,孔隙变小,矿化物颗粒细小,沉积不均匀.结论:牙釉质脱矿后,在口腔环境中可发生再矿化,但矿化程度是有限的,提示在临床上应注意酸蚀时间及酸蚀范围.     

含氟涂料和含氟牙膏对釉面再矿化和抗酸作用的实验研究

目的：观察含氟涂料与含氟牙膏对釉质表面再矿化和抗酸作用。方法：取牛恒切牙制备釉质片;统一酸蚀脱矿后随机分为4组（n＝3）;分别为生理盐水（A组对照）、Duraphat含氟涂料（B组）、Fluor Protector含氟涂料（C组）、含氟牙膏规律处理（D组）;处理期间标本置于人工唾液孵育2周;再次酸蚀;各阶段均用显微硬度仪测定釉面显微硬度、扫描电镜观察釉面,图像分析电镜下釉面微孔隙面积差异;统计分析。结果：首次酸蚀后釉面明显脱矿。分组处理2周,A组釉面再矿化不明显;B组和C组釉面形成涂料保护层;D组釉面可见明显再矿化。再次酸蚀后：A组和D组显微硬度下降,B组和C组涂料保护层有明显抗酸作用。再次酸蚀后,A组和D组釉面微孔隙面积增加（P＜0．05）,但D组小于A组（P＜0．05）;B组、C组无显著变化（P＞0．05）。结论：含氟涂料在釉面形成保护层,具有抗酸蚀和促进釉面再矿化作用;含氟牙膏能促进脱矿釉面再矿化,抗酸作用较弱。     

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目的探讨偏振数码照相结合计算机辅助图像分析法评价邻面去釉后釉质脱矿程度的准确性。方法于2010年3月选取青岛大学医学院附属医院口腔外科门诊因正畸需要拔除的上颌第一前磨牙40颗,沿牙冠颊舌向磨切得到80个标本,随机分为A（空白对照,未进行任何去釉处理）、B（邻面去釉）、C（邻面去釉后使用氟化泡沫）、D（邻面去釉后使用护牙素）4组。体外pH循环60d后,用偏振数码照相结合计算机辅助图像分析法定量测量各组标本邻面去釉及再矿化后的灰度值,以此来评价其釉质脱矿程度。同时用显微硬度仪定量测量各组标本的硬度值作为对照。结果（1）灰度值：A组灰度值最低,B组灰度值最高,C组和D组经过再矿化处理后灰度值较B组降低,差异有统计学意义（P〈0．05）。c组和A、D组之间灰度值差异无统计学意义（P〉0．05）。（2）硬度值：A组硬度值最高,B组硬度值最低,c组和D组经过再矿化处理后硬度值升高,但均较A组低。B组硬度值和其他3组之间比较,差异均有统计学意义（P〈0．05）,而A组与c组、c组与D组之间硬度值比较,差异均无统计学意义（P〉0．05）。结论偏振数码照相结合计算机辅助图像分析法得出的结果与显微硬度仪的定量检测结果相符合,表明了其是一种有效的定量评价釉质脱矿及再矿化效果的方法,值得临床推广。     

不同类型保持器对固定矫治后再矿化的影响

目的:观察不同类型保持器对固定矫治后牙釉质再矿化的影响,以及氟保护剂的再矿化作用。方法:将30名固定矫治结束后釉质脱矿患者随机分为2组(n=15),传统保持器组(A组,117个牙)和压膜保持器组(B组,116个牙)每组再分为3个亚组,分别进行不同再矿化处理。1组:生理盐水;2组:1 mg/m L氟保护剂;3组:350 g/L磷酸凝胶酸蚀+1 mg/m L氟保护剂。每月复诊处理1次并观察半年,用ZWCAD2010软件测量数据并进行统计学分析。结果:拆除固定矫治器时A、B组内以及相应各亚组间釉质脱矿面积差异无统计学意义(P>0.05)。再矿化处理后釉质脱矿面积改变量:A1组0.05);B1组0.05);A1>B1、A2>B2、A3>B3,均P<0.05。结论:用传统保持器更有利于再矿化;给予氟保护剂能够促进再矿化。     

体外应用氟化物对牙酸蚀症再矿化效果的评价-显微硬度测定

目的 用显微硬度测量法研究氟化物对碳酸饮料酸蚀后的乳牙釉质的再矿化作用.方法 收集临床拔除的滞留第二乳磨牙共16颗,制成牙釉质样本.经碳酸饮料浸泡,每天2次,每次10分钟,共5天后,分为对照组(A组)、2%氟化钠溶液组(B组)、含1.23%氟离子凝胶组(C组)和含低氟过饱和钙磷溶液矿化液组(含氟10ppm)(D组)四组,每组16个牙块.经不同的氟化物处理釉质表面,每天1次,每次2分钟,共5天.分别在酸蚀前、酸蚀后和再矿化后用显微硬度计测定釉质表面硬度.数据使用SPSS10.0统计软件包进行单因素方差分析(ANOVA).结果 饮料酸蚀后的牙釉质表面硬度值明显下降.与对照组相比,经2%氟化钠溶液和1.23%氟离子凝胶组处理后的牙釉质表面硬度值均比处理前显著上升(分别为P=0.031和P=0.017),这两组之间的差异无显著性;矿化液处理后的牙釉质表面硬度值无显著变化(P=0.894).结论 显微硬度测定实验显示高浓度的氟制剂2%氟化钠溶液和含1.23%氟离子凝胶能够显著地促进酸蚀釉质再矿化;低氟浓度矿化液在短时间内对酸蚀釉质再矿化作用不明显.     

Whitening techniques using the diode laser and halogen lamp in human devitalized primary teeth

The aim of this study was to make an in vivo assessment of 2 whitening techniques in deciduous teeth, with the variable being the source of energy activation. Ten upper central incisors darkened by trauma were selected and whitening agent used was a 35% hydrogen peroxide. The teeth were distributed into 2 groups: group 1-activation with an infrared diode laser (GaAlAs), and group 2-activation with a halogen lamp. Assessment of whitening was done by color analysis with the Vita 3D scale at 3 different times: before whitening, immediately after whitening, and 1 week after whitening. A Kruskal-Wallace test showed that there were no significant difference between the 2 groups when comparing group 1 and 2 and comparing 2 and 3 immediately and after 1 week of treatment. Laser activation of the whitening agent was not more effective than halogen light activation for root canal-treated deciduous teeth.     

Clinical survey on type of restoration in deciduous teeth

This study was conducted in 533 children with 1,634 treated teeth who visited the Pediatric Dentistry Department at the Chiba Hospital of Tokyo Dental College between January and December, 2003. Restorations on deciduous tooth were categorized by age of patient and tooth type. The following observations were made: Children aged 4 (17.9%) visited the clinic most frequently and this group had the highest number of deciduous restorations (21.3%). Among the 1,634 deciduous teeth restored, metal inlays were provided in 29.4% of total teeth restored, composite resin restorations in 27.2%, stainless-steel crowns in 25.7%, composite resin full crowns in 7.7%, glass-ionomer cement restorations in 6.6%, and amalgam restorations in 3.4%. By age, composite resin was most frequently used in children aged 1 to 3. In children aged 5 to 9, metal inlay was most frequently used. Those aged 4 received mostly stainless-steel crowns. Composite resin restorations were used mostly in anterior deciduous teeth, and metal inlays mostly in deciduous molars. Previous research indicated an increasing trend towards composite resin restorations and composite resin full crowns. The present study also confirmed such a trend. While the use of metal inlays and stainless-steel crowns tended to increase until 1987, the present study indicated a trend to decrease.     

氢氧化钙-碘仿糊剂用于乳牙根管封药的临床研究

目的:观察氢氧化钙-碘仿糊剂应用于乳牙感染根管封药的临床疗效。方法:选择320例乳牙根尖周炎病例,随机分为治疗组(氢氧化钙-碘仿糊剂组)和对照组(甲醛甲酚组)各160例,观察封药后48h,1周的临床疗效。结果:1周后两组疗效有显著差异,氢氧化钙-碘仿糊剂根管封药显效率(91.25%)优于甲醛甲酚组(66.25%)。结论:氢氧化钙-碘仿糊剂应用于乳牙根管封药可有效减少治疗期间的肿痛。     

Retained deciduous mandibular molars in adults: a radiographic study of long-term changes

Management of retained deciduous second molars in the absence of permanent successors can be challenging. The purpose of this retrospective radiographic study was to examine long-term changes in retained deciduous mandibular second molars in adult patients. Specifically, we sought to answer the question, "If an adult has a retained deciduous mandibular second molar and a missing successor, is retaining the deciduous molar a viable treatment option?" From more than 6000 adult patients at the University of Iowa College of Dentistry, 20 were identified who initially had at least 1 retained deciduous mandibular second molar without a permanent successor and who had radiographs spanning 5 or more years after the initial visit. The mean (standard deviation) age at the initial examination was 36.1 (12.9) years, the mean age at the final examination was 48.5 (12.6) years, and the mean examination time span was 12.4 (7.7) years. Of the 28 retained deciduous molars initially identified, 24 (86%) continue to function. The remaining 4 were lost at a mean age of 51.0 (13.9) years and a mean time span after initial examination of 14.3 (10.0) years; this approximates the lifespan of some prosthetic appliances. These 4 mandibular deciduous molars were lost because of caries or periodontal breakdown. Furthermore, we found that the average shortening of all deciduous root lengths was negligible (0.16 mm), and only 6 teeth underwent a change in restoration status. Based on this study in adults and earlier studies in adolescents, we conclude that retaining healthy deciduous mandibular second molars is a viable treatment alternative.     

Orthodontic Findings in the Deciduous and Early Mixed Dentition—Inferences for a Preventive Strategy

AIM AND METHOD: The aim of the present epidemiologic study was to obtain representative basic data on the frequency, extent and age-dependence of malocclusions in the deciduous and early mixed dentition. The developmental tendencies of specific malocclusions were investigated from the aspect of orthodontic prevention. The collective comprised 8,864 preschool and school-aged children, of whom 1,225 were in the deciduous dentition (mean age 4.5 years) and 7,639 in the mixed dentition (mean age 8.9 years). The orthodontic data were clinically assessed as sagittal, transversal, or vertical single-arch and occlusal findings. In addition, the malocclusions were classified according to their primary symptoms. Early infantile habits, tongue dysfunctions, speech defects and incompetent lip closure were registered separately. RESULTS: 57% of the children were found to have malocclusions, with the frequency rising statistically significantly in dependence on age from the deciduous to the mixed dentition (p < or = 0.001). The mean extent of excessive overjet increased significantly from the deciduous to the mixed dentition. Crossbite with mandibular midline discrepancies were observed significantly more frequently in the deciduous dentition. Although the frequency of anterior open bite underwent a significant decline from the deciduous to the mixed dentition, open bite was the malocclusion most frequently associated with dysfunction in both groups. The significant increase in traumatic deep bite in the mixed dentition indicates an unfavorable developmental tendency in this anomaly until after the eruption of the permanent incisors. CONCLUSION: The need for preventive orthodontic therapy and for the intensified application of interceptive and early treatment measures is stressed in view of the high number of malalignments and malocclusions in the deciduous and mixed dentition and the tendency for some forms of malocclusion to deteriorate as the dentition develops.     

乳牙根管治疗术疼痛的临床分析

目的：探讨乳牙根管治疗疼痛的发生率及其与临床因素之间的关系。方法：对牙髓病、根尖周病、牙髓坏死的乳磨牙230例进行根管预备，FC消毒，用氧化锌丁香油糊剂根充，术后拍X线片，如果欠填，则重新充填。结果：乳牙根管预备后疼痛的发生率为7．83％，根充后疼痛的发生率为10．43％。根吸收、病种、超填与疼痛有明显的关系。结论：规范无菌操作、避免器械和根充剂超出根尖孔，可预防乳牙根管治疗的疼痛反应。     

FX玻璃离子水门汀修复乳磨牙的临床疗效

目的：比较FX谆子水门汀（以下简称FX）与银汞合金修复乳磨牙的临床疗效。方法：选择双侧同名乳磨牙患邻He面龋的患儿105例，共226个牙。采用自身对照和随机方法，其中一牙用FX做无创性修复治疗，另一牙用银汞合金修复。经6个月、1年、2年观察，比较修复的成功率。结果：FX、银汞合金修复的成功率分别为92．92％和84．07％，统计学上有显著性差异。结论：临床观察表明FX对修复乳磨牙邻He面龋坏的疗效优于银汞合金。     

Mucogingival interceptive surgery of buccally-erupted premolars in patients scheduled for orthodontic treatment. II. Surgically treated versus nonsurgically treated cases

BACKGROUND: The aim of this 2-year longitudinal study was to compare the width of keratinized gingiva after orthodontic therapy for buccally erupting premolars that had been pretreated by extraction of deciduous teeth alone versus interceptive mucogingival surgery. METHODS: In 8 patients (aged 9 to 12 years) who presented with bilateral buccal eruption of homologous teeth (premolars), one side was randomly treated with extraction of the deciduous molar and mucogingival surgery (test site), while the other side was treated only by extraction of the deciduous molar (control site). All of the subjects underwent orthodontic treatment with fixed appliances. RESULTS: At the baseline visit prior to any treatment, there was no significant difference between the mean amount of keratinized gingiva at test sites (3.06 mm) and control sites (2.93 mm). Two years later, upon completion of orthodontic treatment, there was a significant difference between test (2.93 mm) and control (1.37 mm) sites in the mean width of keratinized tissue. In the control (untreated) group, 2 sites exhibited 1 mm of gingival recession after orthodontic treatment. CONCLUSIONS: Mucogingival interceptive surgery is an effective technique to maintain keratinized tissue in correspondence with buccally-erupted teeth.     

氟化泡沫乳牙防龋临床效果评价

目的：观察和评价在兰州市使用氟化泡沫预防儿童牙龋病的临床效果。方法：实验对象为幼儿园4－5岁儿童。实验组采用4min疗程常规使用方法，一年使用两次，实验前后检查实验组和对照组乳牙患龋情况。结果：实验后，对照组龋患率（80．44％）、龋均（4．65％），明显高于实验组（72．63％、3．85％），两组之间存在显著差异（P＜0．01）。对照组新增龋病发病率（19．91％）、新增乳牙龋均（1．59）明显高于实验组（11．49％、0．83）。发病率两组之间存在显著性差异（P＜0．01）。实验组较对照组新增龋均降低了47．80％。结论：使用氟化泡沫的实验组儿童较对照组儿童龋病患病明显减少。氟化泡沫在兰州地区对儿童的龋病预防是有效的。     

Destructive periodontal disease in healthy children.

This study determined the prevalence of destructive periodontal disease affecting the deciduous dentition among otherwise healthy subjects, who were diagnosed with juvenile periodontitis (JP) in their permanent dentitions. There were 4,757 subjects in this retrospective, cross-sectional study. Diagnosis of JP was based on age (< or = 15 years), negative medical history, and radiographic evidence of arc-shaped alveolar bone loss. The study population was one-third white and two-thirds black and the male/female ratio was 1:1, reflecting the general patient population. The prevalence among whites was 0.3%, with a female/male ratio 4:1; whereas among blacks the prevalence was 1.5%, with a female/male ratio approximately 1:1. Among the black JP subjects with radiographs of the mixed dentition, 85.7% presented evidence of bone loss, and of those with radiographs of the deciduous dentition, 71.4% had discernible alveolar bone loss. This study suggests that JP is much more prevalent in blacks and that it does indeed occur in the prepubertal years affecting the deciduous as well as the permanent dentitions in otherwise healthy children. These data imply the importance of including a periodontal evaluation in the examination of children, using the periodontal probe and radiographs sufficient to adequately view the alveolar bone.