Evaluation of polymerization characteristics and penetration into enamel caries lesions of experimental infiltrants

ObjectivesTo evaluate the properties of experimental infiltrant blends by comparing them with the commercial infiltrant Icon^® and penetration homogeneity into enamel caries lesions.MethodsGroups were set up as follows: G1 (TEGDMA 100%); G2 (TEGDMA 80%, Ethanol 20%); G3 (TEGDMA 80%, HEMA 20%); G4 (TEGDMA 75%, BisEMA 25%); G5 (TEGDMA 60%, BisEMA 20%, Ethanol 20%); G6 (TEGDMA 60%, BisEMA 20%, HEMA 20%); G7 (TEGDMA 75%, UDMA 25%); G8 (TEGDMA 60%, UDMA 20%, Ethanol 20%); G9 (TEGDMA 60%, UDMA 20%, HEMA 20%) and Icon^®. Ten specimens were comprised by each group for the following tests (n = 10): degree of conversion (DC), elastic modulus (EM), Knoop hardness (KH), and softening ratio (SR). Infiltrant penetration was evaluated using confocal microscopy (CLSM). Data were subjected to two-way ANOVA and a Tukey's test (5%). Data comparing experimental materials and Icon^® were analysed using ANOVA and Dunnett's test (5%).ResultsThe highest DC values were found in G1, G7, G8, and G9. The lowest DC values were found in G2, G4, G5, and G6. EM and KHN were significantly lower in HEMA and with ethanol addition for all blends, except for G9. There was no significant difference among the groups regarding SR, and it was not possible to take KHN readings of G2, G5, and G8 after storage. There was no significant difference among groups for infiltrant penetration into enamel lesions.ConclusionsThe addition of hydrophobic monomers and solvents into TEGDMA blends affected DC, EM, and KHN. UDMA added to TEGDMA resulted in an increase in DC, EM, and KHN. Overall, solvents added to monomer blends resulted in decreased properties. The addition of hydrophobic monomers and solvents into TEGDMA blends does not improve the penetration depth of the infiltrants.     

Penetration ability and microleakage of a fissure sealant applied on artificial and natural enamel fissure caries

OBJECTIVES AND METHODS: This study investigated the sealing ability of a current available unfilled fissure sealant applied over sound (n=80), artificially created (n=80) and naturally carious fissures (n=80) under different humidity conditions (90+/-2 and 45+/-2% relative humidity) and etching times (40 and 60s). All samples were submitted to 5000 thermal cycles and examined by light microscopy after sectioning. Microleakage, penetration ability, fissure type, fissure entrance angle, sealant occlusal length, caries location and caries depth were assessed. RESULTS: The significantly longer sealant occlusal length and larger entrance angle exhibited by shallow fissures, contributed to their higher microleakage and smaller amounts of unfilled areas compared to deep fissures. Sealant microleakage was significantly influenced by the condition of the enamel (sound, artificial and natural caries) and the caries location in the fissures, but not by enamel caries depth (D1 and D2), etching time, or humidity condition. Natural caries exhibited significantly higher microleakage than sound or artificially created carious fissures. CONCLUSIONS: Based on the results of this study, it can be concluded that location of caries in the fissure rather than its depth should be taken into account when applying a fissure sealant. When the borders of the fissure sealant are on carious enamel, a significantly higher microleakage must be expected. The artificial caries model was not a suitable method to assess the behavior of natural fissure caries.     

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窝沟封闭作为一种无痛、无害、无创伤的技术,是预防窝沟龋的有效方法。操作步骤包括:清洁、酸蚀、冲洗和干燥、涂布封闭剂、固化、检查。窝沟封闭的防龋效果与封闭剂的保留率直接相关,窝沟封闭的相关操作技术、材料的性能都是与窝沟封闭效果密切相关的因素。     

窝沟封闭和氟保护漆预防学生恒牙龋的疗效观察

目的比较窝沟封闭和氟保护漆预防学生年轻第一恒磨牙窝沟龋的效果。方法应用两种材料对300名小学生进行上下颌第一恒磨牙同体对照封闭试验,左侧使用光固化窝沟封闭剂,右侧使用氟保护漆,于0.5、1.0、2.0年观察3次龋病发生情况。结果 0.5、1.0、2.0年左右侧第一恒磨牙龋齿发生率均无统计学意义。结论窝沟封闭和氟保护漆均有良好的防龋效果。     

玻璃离子预防恒牙窝沟龋的临床效果观察

目的 探讨玻璃离子预防恒牙早期窝沟龋的临床疗效.方法 对189名7～8岁学生的512颗第一恒磨牙应用玻璃离子行窝沟封闭,试验组为未完全萌出或已患有窝沟浅龋的第一恒磨牙,共269颗;对照组为已萌出且无龋坏的第一恒磨牙,共243颗.试验组中未完全萌出的第一恒磨牙和对照组已完全萌出且无龋坏的第一恒磨牙彻底清洁窝沟,隔湿干燥后采用指压法用玻璃离子材料进行窝沟封闭;试验组中已患有窝沟浅龋的第一恒磨牙采用金刚砂球钻彻底敞开窝沟后,用同样的方法进行窝沟封闭.封闭后3、6、12个月复查,观察两组玻璃离子材料的保留情况及新增龋坏情况.结果 封闭后3、6、12个月试验组封闭剂的完全脱落率分别为7.1％、10.1％、13.1％,和对照组窝沟封闭剂完全脱落率之间差异无统计学意义(P＞0.05),且2组均无新增龋坏发生.结论 玻璃离子用于未完全萌出或已患有窝沟浅龋的第一恒磨牙的窝沟封闭,能有效预防恒牙早期窝沟龋,扩大了窝沟封闭的适应证.     

氟保护漆与玻璃离子水门汀窝沟封闭剂的防龋效果比较

目的:比较氟保护漆与玻璃离子水门汀窝沟封闭剂预防年轻第一恒磨牙窝沟龋的临床效果。方法:622例6～8岁儿童,随机分为3组,A试验组207例、335颗牙;B试验组205例、327颗牙和对照组210例、354颗牙。对A组儿童第一恒磨牙应用氟保护漆,每半年1次,对B组儿童第一恒磨牙应用玻璃离子水门汀窝沟封闭剂,对照组为空白对照。试验期3a,采用SPSS10.0软件包经χ2检验比较3组的龋病发病率。结果:3a后,A、B实验组龋病发生率均低于对照组,有显著差异(P<0.01),而A、B2组龋病发生率无显著性差异。结论:氟保护漆与玻璃离子水门汀窝沟封闭剂均有良好的防龋效果。     

可见光固化窝沟封闭剂治疗磨牙窝沟龋的临床效果观察

目的：探讨可见光固化窝沟封闭剂治疗磨牙Ｈｅ面窝沟龋的临床应用价值。方法：对１２０例６￣１５岁患者的Ｈｅ面窝沟龋在去龋后用光固化窝沟封闭剂对龋损部位及窝沟进行封闭术,并采用对侧同名牙或邻牙也有窝沟龋者作对照研究。结果：随访３年发现该方法能有效阻止龋坏的进一步发展,１年内未发现一例中龋,而对照组有３２．９４％牙发现为中龋,２￣３年后中龋发生率亦有明显差异。３年后实验组继发龋发生率为４．３％,涂膜完全保     

Retention of a fissure sealant with caries reduction in Finnish children after six months

abstract — The purpose of this study was to test the retention as well as the caries reduction potential of a fissure sealant under Finnish dietary conditions. The 150 children who served as subjects were selected on the basis of having at least one pair of sound permanent molars. Two hundred first molars, 43 premolars and 119 primary molars were sealed, while the respective tooth from the other side of the jaw was left untreated and used as the control. The findings after 6 months revealed that all 362 sealants persisted. Among the sealants of the first permanent molars, 99% were in excellent condition. All sealants of the permanent premolars and of the primary molars were excellent. Among the permanent control molars 43 (22%) showed carious fissures while among the sealed permanent molars, only 3 (1.5%) had carious fissures. This gives a 93% reduction of the fissure caries. Both the control and the sealed premolars were all sound. None of the sealed primary molars were decayed compared to 7.6% decayed on the control side.     

Influence of application time on penetration of an infiltrant into natural enamel caries

Objective

Caries infiltration is an innovative approach to treat medium stages of caries that bridges the gap between preventive and invasive measures, whereby hard tissues are preserved. Special low viscosity resins (infiltrants) showed almost complete penetration into natural lesions when applied for 5 min. Since shorter application times seem to be clinically more feasible, the aim of this in vitro study was to compare the penetration of an infiltrant (Icon pre-product; DMG, Hamburg, Germany) into natural caries lesions after various application times.

Methods

Extracted permanent human posterior teeth showing non-cavitated proximal caries lesions were infiltrated for either 0.5, 1, 3, or 5 min (n = 20) and light-cured. Specimens were prepared and lesion (LD) as well as penetration depths (PD) were analysed using dual fluorescence confocal microscopy.

Results

PD [median (Q25;Q75)] at maximum LD after 0.5 min [159 (27;340) μm] and 1 min [152 (69;375) μm] were significantly lower compared to those after 3 min [414 (338, 518) μm] and 5 min [407 (332;616) μm] (p < 0.05). Deep lesion parts (PD > 500 μm) could be penetrated almost completely after 3 min [98 (88;100)%] and 5 min [100 (81;100)%] application.

Conclusions

Thus, 3 min application of an infiltrant seems to be sufficient to achieve an almost complete penetration of enamel caries.     

Clinical comparison of a flowable composite and fissure sealant: A 24-month split-mouth,randomized, and controlled study

Objectives

The aim of this clinical study was to evaluate the retention rate and caries-prevention effect of a flowable composite compared to a conventional resin-based sealant in a young population over a 24-month period.

Methods

Thirty-four patients, ranging in age from 16 to 22 years, diagnosed with at least 2 non-cavitated pit-and-fissure caries in the first and second molars were selected for this randomized split-mouth design trial. A total of 220 sealants, were placed in 117 upper molars and 103 lower molars. The teeth were sealed with a flowable resin composite (Tetric Evo Flow) or a sealant material (Helioseal F). Each restoration was independently evaluated in terms of retention and the presence of caries at baseline and at 1, 6, 12, and 24 months. Data were analyzed using non-parametric Mann–Whitney U and Friedman 1-way ANOVA tests at p < 0.05.

Results

Tetric Evo Flow showed complete retention with 100%, 95.5%, 93.8%, and 88.5% at 1, 6, 12, and 24-month evaluations, respectively, while Helioseal F retention rates were 98.1%, 95.5%, 94.8%, and 85.4%, respectively, for the same evaluation periods. At the 24-month recall, 4 (4.2%) total losses were observed in subjects treated with Tetric Evo Flow and 2 total losses (2.1%) for Helioseal F, respectively. No significant differences were observed between the materials in retention rates or caries incidence for each evaluation period (p > 0.05).

Conclusion

Placement of flowable composite as fissure sealants in the younger population seems to be as effective as conventional fluoride containing fissure sealants for the prevention of fissure caries.

Clinical relevance

The use of a flowable composite as a fissure sealant material, in conjunction with a total-etch, single bottle adhesive, yielded better retention than did the conventional fluoride containing resin-based fissure sealant over a 24-month period in young patients.     

含氟封闭剂在乳磨牙早期窝沟龋预防性树脂充填术中的临床应用

目的：评价Helioseal F窝沟封闭剂结合预防性树脂充填术在儿童乳磨牙早期窝沟龋中的临床应用效果。方法：382颗患牙,随机分为两组。实验组192颗,应用Helioseal F窝沟封闭剂;对照组190颗,应用Helioseal窝沟封闭剂。两组病例均在预防性树脂充填术后在面进行窝沟封闭。进行1～3年随防观察。结果：经过3年随防,HeliosealF窝沟封闭剂3年完全保留率分别为：94.12%、86.49%、78.65%;龋病发生率分别为：0%、2.16%、3.93%;实验组龋病发生率显著低于对照组（P〈0.05）;封闭剂保留率与龋病发生率成负相关。结论：Helioseal F窝沟封闭剂结合预防性树脂充填术可有效防治儿童乳磨牙早期窝沟龋,其防龋效果优于传统窝沟封闭剂。     

纳米金刚石填料对光固化窝沟封闭剂渗透性的影响

目的：观察纳米金刚石填料对光固化窝沟封闭剂渗透性的影响，并与气相二氧化硅作比较。方法：在光固化窝沟封闭剂中加入10、20g／L的纳米金刚石和20g／L的气相二氧化硅，检测其渗透性的变化，并对黏结界面作形态学观察。结果：添加10、20g／L的纳米金刚石后，窝沟封闭剂的渗透性不受影响，而添加20g／L的气相二氧化硅后渗透性显著降低，形态学观察见树脂突形成不良。结论：适当比例的纳米金刚石填料对窝沟封闭剂的渗诱件无明显影响．效果优于气相二氧化硅。     

氟保护漆、玻璃离子与树脂类窝沟封闭剂预防低龄儿童窝沟龋效果观察

目的研究氟保护漆、玻璃离子与树脂类窝沟封闭剂预防低龄儿童窝沟龋的效果,探讨在隔湿有限的情况下,减少操作技术敏感性并能有效预防低龄儿童窝沟龋的方法。方法 3～5岁儿童370例,采用自身对照设计,口内8颗乳磨牙分布在4个象限中,4个象限随机选择设置为空白组、氟保护漆多乐氟组、玻璃离子GC FujiⅦ组、树脂类Clinpro^TM Sealant组,分别于6、12、24、36个月复查,观察乳磨牙窝沟封闭剂的保留率和患龋率。结果 6、12、24个月时,GC FujiⅦ组和Clinpro^TM Sealant组的材料保留率差异无统计学意义;36个月时,Clinpro^TM Sealant组封闭剂的保留率高于GC FujiⅦ组(P<0.05)。6个月时,多乐氟组、GC FujiⅦ组、ClinproTM Sealant组患龋率均低于空白组,差异有统计学意义(P<0.001),多乐氟组、GC FujiⅦ组、Clinpro^TM Sealant组三组患龋率差异无统计学意义,12、24、36个月时,GC FujiⅦ...     

2种光固化窝沟封闭剂的防龋效果评价

目的:探讨光固化窝沟封闭剂预防窝沟龋的临床疗效。方法:选择162例6￣8岁儿童的416颗健康恒牙,分为2组,分别采用窝沟釉质成形封闭术和窝沟杯刷清洗封闭术对窝沟进行封闭,比较2种封闭术封闭剂保留率和龋病发生率,并通过自身对照,观察2种封闭术的临床效果,采用SPSS10.0统计软件包进行χ2检验。结果:窝沟釉质成形封闭术3年封闭剂保留率和龋病发生率分别为85.4%、0.9%,窝沟杯刷清洗封闭术3年封闭剂保留率和龋病发生率分别为63.8%、6.7%,2组封闭剂保留率和龋病发生率均有显著性差异(P<0.05)。结论:2种封闭术均有良好的临床疗效,窝沟釉质成形封闭术的防龋效果优于窝沟杯刷清洗封闭术。     

2种窝沟封闭术预防儿童龋病的效果评价

目的 比较窝沟釉质成形术和常规窝沟封闭术预防儿童龋病的临床效果. 方法 随机选择6. 0 ~8. 5岁牙齿健康儿童50人,共82对第一恒磨牙(同颌的左、右侧第一恒磨牙为1对),采用自身对照方法,右侧第一恒磨牙用窝沟釉质成形封闭术(A组),左侧第一恒磨牙用常规窝沟封闭术(B组). 封闭术后1年、2年、3年后复查,评价两种窝沟封闭术的疗效. 结果 封闭术后1 年、2 年、3 年龋病发生率 A 组分别为2. 5%、3. 9%、5. 7%,B组分别为2. 5%、10. 4%、15. 7%,2组封闭术后2年和3年的龋病发生率差异有统计学意义(P<0. 05).结论 和常规窝沟封闭术相比,窝沟釉质成形封闭术对预防儿童龋病具有更好的远期临床疗效.     

第一恒磨牙窝沟封闭3年临床效果观察

目的通过3年随访观察窝沟封闭技术预防8岁儿童第一恒磨牙龋的临床效果。方法试验组805人,对照组245人,分别进行口腔检查,对试验组符合适应证的2 190颗第一恒磨牙进行窝沟封闭,分别于1、2、3年后复查试验组封闭剂保留情况和两组第一恒磨牙患龋状况,计算封闭剂保留率和比较两组第一恒磨牙患龋率。结果试验组3年随访封闭剂保留率分别为78.35%、69.56%、69.31%,第一恒磨牙患龋率分别为9.45%、9.91%、10.87%,龋均分别为0.10、0.11、0.12,而对照组3年随访第一恒磨牙患龋率分别为14.29%、17.26%、18.95%,龋均分别为0.15、0.20、0.21。对3年的患龋率分别进行比较,两组间差异均有统计学意义,第2、3年龋均两组间差异有统计学意义。结论窝沟封闭在第一恒磨牙防龋应用中效果好。     

玻璃离子非创伤性充填技术与光固化树脂封闭乳牙窝沟的效果观察

目的比较玻璃离子联合非创伤性充填技术(atraumatic restorative treatment,ART)进行窝沟封闭和光固化树脂窝沟封闭两种方法应用于幼儿乳牙的效果。方法按自身半口随机对照的方法,采用干预试验对89名3岁幼儿左或右半口符合条件的乳磨牙进行玻璃离子联合ART窝沟封闭(ART玻璃离子组),对侧半口符合封闭条件的乳磨牙进行树脂窝沟封闭(树脂组)。ART玻璃离子组共188颗牙齿,树脂组共168颗牙齿。术后记录两组的术中不适发生情况。封闭后6个月、18个月检查窝沟封闭剂的保留情况和新发龋齿情况。对结果进行统计学分析。结果术中不适ART玻璃离子组1例,树脂组8例,两组比较差异无统计学意义(P=0.160)。封闭后6个月、18个月,ART玻璃离子组的封闭物脱落率分别为5.85%、21.81%,树脂组的封闭物脱落率分别为21.43%、38.10%,6个月及18个月时,两组差异均有统计学意义(P<0.05)。6个月、18个月时复查患龋率,ART玻璃离子组分别为1.60%、3.19%,树脂组分别为5.95%、5.95%。6个月时两组差异有统计学意义(P=0.029),18个月时差异无统计学意义(P=0.209)。结论玻璃离子联合ART窝沟封闭应用于幼儿乳牙时,封闭物脱落率低,术中不适少,防龋效果肯定,可在低龄幼儿防龋工作中推广。     

窝沟封闭技术预防第一恒磨牙龋病的效果观察

目的评价窝沟封闭技术预防第一恒磨牙龋病的效果。方法选择155名7～8岁儿童,其中80名儿童305颗第一恒磨牙进行窝沟封闭作为实验组,75名儿童287颗第一恒磨牙不作任何处理视为对照组,分别于封闭后6个月和12个月观察其新生龋的发生情况。结果实验组6个月和12个月后的发病率分别为0．98％和2．30％,对照组的发病率分别为10．45％和19．16％,两组经统计学处理,差异有高度统计学意义（P〈0．01）,实验组的龋病发病率明显低于对照组。结论窝沟封闭可以有效地降低儿童第一恒磨牙新生龋的发生;窝沟封闭是一种无痛、无创伤、安全简便且有效的防龋技术。     

Effects of glass ionomer cement, resin-based pit and fissure sealant and HF applications on occlusal caries in a developing country field trial

Abstract The aim of this community-oriented study was to evaluate different methods to prevent fissure caries. The following products and measures were tested: 1) glass ionomer cement (GIC) applied by dentist; 2) same material applied by short term (3 days) trained personnel (teachers); 3) application of a 0.5% HF solution three times; 4) an established autopolymerized resin based sealant (Delton). The study was performed in Bangkok, Thailand, a city in a developing country experiencing increasing caries prevalence. Children with at least three sound permanent molars from two age groups, 7–8 and 12–13-yr-olds respectively were chosen from very low to medium socioeconomic level families. 1264 children were systematically assigned to experiment or control groups based on school and DMFT. For the younger age group, the 2 yr mean DFS occlusal increment in the Control group was 0.66 surfaces. Significantly lower increments were observed in the GIC experimental group: O.I7 surfaces applied by the teachers and 0.32 applied by dentist, corresponding to 74% and 52% reductions, respectively. The mean increment in the HF group was 0.44 surfaces, a 33% reduction in relation to the Control group. For the 12–13-yr-olds, the mean occlusal surface DF increment was 0.70 surfaces in the Control group. Almost no occlusal increment was found in the Delton group, 0.05 DFS, a 93% reduction. In the GIC Dentist group, the DFS increment was 0.48 and in the Teacher group 0.56, corresponding to 31% and 20% reduction, respectively. A slight and nonsignificant increase of caries in relation to the Control group was observed in the HF group. Retention of Delton sealant was high, 92% after 6 months, retention of the GIC sealants was low. At the 6-months checkup, only 2–8% of these sealants were still present and also after reapplication, a majority was lost.