Influence of a proximal margin elevation technique on marginal adaptation of ceramic inlays

Abstract

Purpose. Evaluating the effect of a proximal margin elevation technique on marginal adaptation of ceramic inlays. Methods. Class II MOD-cavities were prepared in 40 human molars and randomly distributed to four groups (n = 10). In group EN (positive control) proximal margins were located in enamel, 1 mm above the cementoenamel junction, while 2 mm below in groups DE-1In, DE-2In and DE. The groups DE-1In, DE-2In and DE simulated subgingival location of the cervical margin. In group DE-1In one 3 mm and in group DE-2In two 1.5 mm composite layers (Tetric) were placed for margin elevation of the proximal cavities using Syntac classic as an adhesive. The proximal cavities of group DE remained untreated and served as a negative control. In all groups, ceramic inlays (Cerec 3D) were adhesively inserted. Replicas were taken before and after thermomechanical loading (1.200.000 cycles, 50/5°C, max. load 49 N). Marginal integrity (tooth-composite, composite-inlay) was evaluated with scanning electron microscopy (200×). Percentage of continuous margin (% of total proximal margin length) was compared between groups before and after cycling using ANOVA and Scheffé post-hoc test. Results. After thermomechanical loading, no significant differences were observed between the different groups with respect to the interface composite-inlay and tooth-composite with margins in dentin. The interface tooth-composite in enamel of group EN was significantly better compared to group DE-2In, which was not different to the negative control group DE and DE-1In. Conclusion. Margin elevation technique by placement of a composite filling in the proximal box before insertion of a ceramic inlay results in marginal integrities not different from margins of ceramic inlays placed in dentin.     

Interfacial gaps of resin cemented ceramic inlays

A method was developed for measuring presence, location and extent of interfacial contraction gaps of resin-cemented ceramic inlays in dentin cavities. Cylindrical ceramic inlays were cemented using one of 12 commercially available resin composite cements to make film thickness of 200-μm. Cross-sections revealed absence of marginal gaps but contraction gaps occurred at all dentin-cement interfaces at the cavity floors and ranged from 1.6 to 7.1 μm. This was equivalent to 0.8-3.5% of the cement film thickness and was 3-10 times greater than the wall-to-wall contraction in percent observed when resin composites are used as filling materials in 3-5 mm butt-joint dentin cavities. The results support the theory that contraction gaps developing adjacent to thin films of resin cements reach size equivalent to the cement film thickness multiplied by the volumetric polymerization shrinkage of the cement.     

In vitro evaluation of marginal and internal adaptation after occlusal stressing of indirect class II composite restorations with different resinous bases

Composite inlays are indicated for large cavities, which frequently extend cervically into dentin. The purpose of this study was to compare in vitro the marginal and internal adaptation of class II fine hybrid composite inlays (Herculite, Kerr) made with or without composite bases, having different physical properties. Freshly extracted human molars were used for this study. The base extended up to the cervical margins on both sides and was made from Revolution (Kerr), Tetric flow (Vivadent), Dyract (Detrey-Dentsply) or Prodigy (Kerr), respectively. Before, during and after mechanical loading (1 million cycles, with a force varying from 50 to 100 N), the proximal margins of the inlay were assessed by scanning electron microscopy. Experimental data were analysed using non-parametric tests. The final percentages of marginal tooth fracture varied from 30.7% (no base) to 37.6% (Dyract). In dentin, percentages of marginal opening varied from 9.2% (Tetric Flow) to 30.1% (Prodigy), however, without significant difference between base products. Mean values of opened internal interface with dentin varied from 11.06% (Tetric Flow) to 28.15% (Prodigy). The present results regarding dentin adaptation confirmed that the physical properties of a base can influence composite inlay adaptation and that the medium-rigid flowable composite Tetric Flow is a potential material to displace, in a coronal position, proximal margins underneath composite inlays.     

Proximal direct composite restorations and chairside CAD/CAM inlays: Marginal adaptation of a two-step self-etch adhesive with and without selective enamel conditioning

The aim of this study was to evaluate the marginal adaptation of CEREC ceramic inlays, CEREC composite inlays and direct composite restorations in unbeveled proximal slot cavities under artificial aging conditions. Two groups of each restoration type were prepared (n = 6), one group with a self-etch adhesive, the other group with H₃PO₄ enamel etching before the self-etch adhesive application. Replicas were generated before and after long-term thermo-mechanical loading under dentinal fluid simulation and margins were evaluated at ×200 magnification in the scanning electron miscroscope (SEM). Statistically, significant differences were found before and after loading with respect to the percentages of “continuous margins”, the direct composite filling with H₃PO₄ enamel etching giving the lowest percentages of “continuous margins” after loading (p < 0.05). The highest percentage of “continuous margin” was attained by composite inlays without H₃PO₄ enamel etching. However, these results were not significantly different from ceramic inlays after stressing. Polymerization shrinkage is still one critical property of composite restorative materials. The marginal adaptation of indirect adhesive proximal slot restorations without enamel bevels both fabricated out of composite and ceramic is better than that of directly placed composite restorations. Clinical significance: Polymerization shrinkage is still one critical property of composite restorative materials. The marginal adaptation of indirect adhesive proximal slot restorations without enamel bevels both fabricated out of composite and ceramic is better than that of directly placed composite restorations.     

微瓷树脂嵌体和复合树脂嵌体微渗漏的对比研究

目的 对比研究1种微瓷聚合树脂嵌体和另外3种复合树脂嵌体的边缘微渗漏情况,为临床选择嵌体材料提供参考。方法 将80颗健康离体上颌前磨牙随机分为8组,每组10颗,嵌体窝洞制备后,分别用微瓷聚合树脂Ceramage（C）和复合树脂Brilliant new line(B)、Z350(Z)、P60(P)间接法制成嵌体,每种材料2组,使用即刻牙本质封闭(immediate dentin sealing,IDS)/延时牙本质封闭(delayed dentin sealing,DDS)技术粘结,冷热循环品红染色后,用金刚砂片将实验牙切开,体视镜下观察微渗漏。结果 4种树脂嵌体龈壁与轴壁微渗漏无显著性差异（P>0.05）,各IDS组与DDS组微渗漏亦无显著性差异（P>0.05）。无论龈壁还是轴壁,采用IDS或DDS粘结技术,4种材料之间皆有显著性差异（P<0.05）并且渗漏情况一致。微渗漏从小到大依次均为C、Z、P、B。结论 单从微渗漏方面评价,Ceramage和Z350均为制作树脂嵌体的良好选择。     

不同材料嵌体与牙体间的边缘密合度研究

目的：比较三种不同材料嵌体与牙体间的边缘密合度。方法：在30颗离体牙上备洞，分别用水晶瓷、银钯合金、镍铬合金制作嵌体，在体现显微镜下测量嵌体与牙窝洞间的边缘密合度。结果：银钯合金嵌体、水晶瓷嵌体与牙窝洞边缘间的间隙较小，镍铬合金嵌体与牙间的间隙较大，且有统计学意义。结论：银钯合金嵌体、水晶瓷嵌体边缘密合度好，可满足临床牙体修复的需要。     

Clinical study of the internal gaps of zirconia and metal frameworks for fixed partial dentures

The aim of this clinical study was to compare the internal gaps between abutment teeth and posterior fixed partial dentures (FPDs) fabricated utilizing milled zirconia and cast gold-alloy frameworks. As part of an ongoing randomized controlled clinical trial, 32 three-unit FPDs (16 zirconia and 16 metal-ceramic) in 25 patients were randomly selected for adaptation measurements. During the bisque-stage ceramic try-in, an A-silicone impression material was placed between the abutment teeth and the framework. The internal gap, corresponding to the thickness of the replica, was measured under magnification at the following locations: cervical, axial, and occlusal (cusp-tips and central). The internal gaps of FPDs with zirconia frameworks were significantly larger in cervical, axial, and centro-occlusal regions (cervical: 189.6 ± 71.8  μ m vs. 118.6 ± 31.5  μ m; axial: 140.5 ± 38.3  μ m vs. 95.7 ± 18.1  μ m; and centro-occlusal: 192.0 ± 66.5  μ m vs. 153.1 ± 69.8  μ m). The cervical gaps next to the pontics were significantly larger compared with those of the outer walls in both types of FPDs (zirconia: mean difference 67.7 ± 114.7  μ m; metal-ceramic: mean difference 30.0 ± 71.2  μ m). Posterior three-unit FPDs incorporating milled zirconia frameworks exhibited larger internal gaps than those constructed using conventional metal-ceramic techniques.     

Marginal adaptation of ceramic and composite inlays in minimally invasive mod cavities

Objectives

This study aims to evaluate the effect of a minimally invasive mesial–occlusal–distal (mod) preparation on the marginal adaptation of ceramic and composite inlays with the aim of saving sound dental substance.

Materials and methods

Class II mod cavities were prepared in 50 extracted human molars and randomly allocated to five groups (n?=?10). In all groups, the mesial–proximal box margins were located in the dentin, 1 mm below the cementoenamel junction (CEJ), while the distal box margins were 1 mm above the CEJ. In groups A and B, conventional standard preparations with a divergent angle of α?=?6° were prepared. In groups C, D, and E, minimally invasive standard preparations with a convergent angle of α?=?10° were prepared. In groups A and D, composite inlays and, in groups B and C, ceramic inlays were fabricated (chairside economical restoration of esthetic ceramics (CEREC)) and adhesively inserted. In group E, a direct composite filling using the incremental technique was placed. Replicas were taken before and after thermomechanical loading (1,200,000 cycles, 50/5 °C, max. load 49 N). Marginal integrity (tooth–luting composite, luting composite–inlay) was evaluated by scanning electron microscopy (×200). The percentage of continuous margins in the different locations was compared between and within groups before and after cycling, using ANOVA and Scheffé post hoc test.

Results

After the thermomechanical loading, no significant differences were observed between the different groups with respect to the interface of luting composite–inlay. At the interface of tooth–luting composite for preparations involving the dentin, groups A and B behaved significantly better compared to the control group E, which in turn were not different to groups C and D.

Conclusion

Composite and ceramic inlays inserted in minimally invasive prepared mod cavities result in margins not different from those of inlays placed in conventional mod preparations. Direct composite filling margins, however, were inferior to those attained by conventional indirect restorations.

Clinical relevance

Minimally invasive preparations for mod inlays with undercuts show marginal adaptation equal to that of conventional inlay preparation design.     

冷热循环对自粘接树脂水门汀边缘适合性的影响

目的：对自粘接树脂水门汀（RelyX Unicem）与传统树脂水门汀系统（Panavia F,Variolink Ⅱ,Vtique）粘接嵌体边缘适合性进行对比研究。方法：48个新鲜拔除的第一磨牙分为4组,每组12个,分别选用d种树脂水门汀系统粘接嵌体,每组试件选取4个分别冷热循环0次,5000次,10000次后,放置于0．5％的品红溶液中染色24h,顺着嵌体长轴纵剖后在体视显微镜下观察微渗漏情况。结果：4种树脂水门汀系统在不同的冷热循环次数沿着粘接界面表现出低的微渗漏,4种树脂水门汀系统粘接嵌体无明显统计学差异义。结论：自粘接树脂水门汀具有与传统树脂水门汀相似的良好的边缘适合性。     

间接树脂嵌体与瓷嵌体三年应用比较

目的:比较树脂嵌体及瓷嵌体用于修复后牙缺损的临床治疗效果.方法:选择中老年患者,临床完成Ceramage树脂嵌体50个,Vita mark II瓷嵌体46个,术后即刻、1年及3年,参考美国公共健康会(USPHS)标准,对其临床效果进行观察.结果:2种嵌体在边缘着色、边缘密合度及继发龋发生等方面差异无统计学意义(P>0....     

Gradia微瓷聚合复合树脂嵌体修复牙体缺损的临床研究

目的：观察Gradia微瓷聚合复合树脂嵌体修复牙体缺损的临床疗效。方法：53例后牙牙体缺损病例采用Gradia微瓷聚合复合树脂嵌体进行修复共125件。分别于修复后2、6、12、24个月进行随访观察,评价修复体完整度、边缘适合度、外形及颜色匹配等。结果：随访125件修复体,均无继发龋发生,其中109例修复体完好,具有良好的边缘密合度,107例颜色匹配,5例修复体折裂,临床合格率87.2%。结论：Gradia微瓷聚合树脂嵌体能满足牙体缺损修复的临床要求。     

复合树脂嵌体修复儿童第一恒磨牙缺损的临床观察

[摘要] 目的 观察复合树脂嵌体修复儿童第一恒磨牙牙体缺损的临床效果。方法 对儿童第一恒磨牙牙体缺损分别采用复合树脂嵌体技术和复合树脂直接充填术,复合树脂嵌体技术组75颗,复合树脂直接充填组78颗,1年后复诊检查,评价标准采用改良USPHS评价标准。结果 复合树脂嵌体技术组的临床成功率在固位情况、边缘密合度、继发龋、牙龈指数指标上高于复合树脂直接充填修复组,并且存在显著差异(P<0.05)。在色泽协调性和磨耗程度指标上,临床成功率虽高于复合树脂直接充填修复组,但统计学上无显著差异(P>0.05)。结论 复合树脂嵌体修复术组临床效果优于复合树脂直接充填术。     

Microleakage of different cementation techniques in Class V ceramic inlays

Microleakage between the restorative materials and the cavity walls of teeth remains a problem. The purpose of this study was to evaluate the microleakage around Class V ceramic inlay restoration using three different cementation techniques. Class V preparations were made on the buccal surfaces of 45 freshly extracted premolar teeth. The teeth were randomly divided into three groups of 15. In the first group, dentine bonding agent (DBA) (Clearfil Liner Bond 2V) was applied immediately after the tooth preparation (D-DBA). In the second group, DBA was applied to the prepared cavities while luting ceramic inlays (I-DBA). In the third group, DBA was not applied at either stage (No-DBA). Impressions were made and ceramic inlays (Ceramco II) fabricated and cemented in the Class V cavities. The restorations were stored in water at room temperature for 24 h. All restorations were thermocycled and then subjected to a dye penetration test. After sectioning, leakage at cavity/restoration interface was scored. Statistical analysis was performed using Kruskal-Wallis, Mann-Whitney U and Wilcoxon's signed tests. Results showed no significant difference among three different cementation techniques (P > 0.05). Microleakage at the dentine margins was greater than that at the enamel margins (P < 0.05).     

Marginal adaptation of resin in relation to application technique and use of a calcium hydroxide liner

Abstract – The marginal adaptation of a restorative resin was examined in cone-shaped cavities prepared in extracted human teeth. The use of a thin layer of a Ca(OH)₂ liner in the bottom of the cavities did not influence the wall-to-wall (wtw) polymerization contraction and it did not affect the gap-reducing efficacy of a dentin-bonding agent. The wtw contraction was markedly increased when the restorative resin was applied in two layers parallel to the free surface of the cavity; the reason for this is supposed to be that the ratio between the volume of the filling (V) and the area of the cavity wall (A) is increased for the second layer compared to the V/A ratio found in cavities filled with one increment.     

Longevity of ceramic inlays and onlays luted with a solely light-curing composite resin

OBJECTIVES: To determine the longevity of heat-pressed glass ceramic inlays and onlays luted with solely light-curing composite resin. METHODS: The records of patients who had received a ceramic inlay or onlay at the Heidelberg University Department of Conservative Dentistry from 1993 to 2002 were evaluated. The mean observation time and the survival probability of the ceramic inlays and onlays was calculated with the aid of the Kaplan-Meier algorithm. This was done for the total number of all restorations as well as for various subgroups (number of surfaces, tooth type, endodontic condition at the time that the ceramic restoration was incorporated, experience of operator). The log-rank test was used to compare groups and look for significant differences, and p<0.05 was set to be statistically significant. In addition, 95% confidence intervals of the survival probability values were computed. RESULTS: At the time of the last observation, 783 (96.7%) of these restorations were still in place. The mean observation period for all ceramic restorations was 17.3 months (SD 20.2), with an observation interval of between 0 and 116 months. The last loss of a ceramic restoration was observed 45 months after it had been placed, so that the survival probability of all ceramic restorations amounted to p=0.90 (95% confidence interval 0.86-0.94) from this time onward. Factors such as endodontic condition of tooth, type of tooth, position of tooth, extent of restoration, experience of operator or gender of patient had no significant influence on the survival probability of the ceramic restorations. CONCLUSIONS: Heat-pressed glass ceramic inlays and onlays can be used successfully in routine clinical therapy. In addition, this type of inlays and onlays can be placed successfully with solely light-curing composite resin.     

不同大小MO洞型复合树脂嵌体修复应力分布的有限元分析

目的 探讨复合树脂嵌体修复后,近中邻（meiso-occlusal,MO）洞型面深度及宽度变化对牙体抗力的影响。方法采用锥形束CT（cone beam computed tomography,CBCT）扫描,结合Mimics、Geomagic Studio逆向工程等软件,建立不同大小邻（II类）MO洞型树脂嵌体修复的三维有限元模型,用ANSYS Workbench软件网格划分并求解分析各模型内部牙体及嵌体在垂直、舌向45°加载下主应力峰值及Von-mises应力分布情况。结果大小不同的MO洞型以复合树脂嵌体修复时,龈壁对应处是嵌体的主要应力所在,洞底部近髓腔处是牙体的主要应力集中区。随着面洞型深度、宽度增加,牙体、修复体的最大应力峰值及Von-mises应力集中区分布范围加大;牙体Von-mises应力受洞型宽度的影响更大,嵌体的Von-mises应力受洞型深度增加影响更大。侧向加载大大增加了牙体和修复体的应力峰值。结论MO洞型以树脂嵌体修复后,洞深、洞宽度加大及侧向加载增加了牙体与嵌体的应力峰值,改变了应力集中区分布范围。     

嵌体修复体的微漏分析

目的:用热循环法对IPS-EmpressII热压铸瓷嵌体、Brilliant树脂嵌体与金合金嵌体边缘微漏的情况作比较。方法:实验中50个完整离体后磨牙浸泡在生理盐水中三周,每个牙被预备为邻洞型,20个无洞斜面,30个有洞斜面。样品被随机分为5组,第1组为瓷嵌体(IPS-EmpressII)用VariolinkII 粘结系统粘结,第2组为树脂嵌体(Coltene Brillant composites) 光/热聚合处理,用One Coat Bond , Duo Cement粘结。第3, 4, 5组为金合金嵌体(Argenco 50 typeIV),分别用松风羧酸水门汀粘固(HY-Bond Polycaboxylate)、松风玻璃离子水门汀粘固(HY-Bond Glasionomer CX)、登士柏(Poly-F)磷酸锌水门汀粘固。对样本作8℃-60℃300次冷热循环后,样品放在0.5%碱性品红中37℃水中恒温24小时,所有样品用金刚砂片沿嵌体长轴作对称性片切,切缘通过修复体近远中中心。在2 × 15倍立体显微镜下对染色深度作测定,统计学用方差分析法,作F 检验和q检验。结果:第1组与第3、4组 之间差异无显著性,第1、2组之间差异有显著性,第2、5组与第3、4组之间差异有显著性。结论:热循环处理IPS-EmpressII瓷嵌体的微漏值最小,树脂组的微漏值大于瓷嵌体组及金嵌体。金合金用松风玻璃离子和松风羧酸锌水门汀粘结微漏值比用登士柏Poly-F磷酸锌水门汀粘结微漏值小。     

In vivo and in vitro evaluation of marginal fit of class II ceromer inlays

The aim of this study was to evaluate the marginal adaptation of class II ceromer (Targis, Vivadent) indirect inlay restorations under both in vivo and in vitro conditions. Twenty Targis inlays were produced for class II inlay cavities (13 mandibular and seven maxillary teeth) in 20 patients. The in vivo adaptation of the inlay to the tooth cavity was evaluated by means of silicone replica technique. For in vitro evaluation, 20 mesio-occluso-distal (MOD) Targis inlays were made in extracted upper molars. Half of the inlays were cemented with Variolink high-viscosity resin cement while the other half was cemented with Variolink Ultra. The replica specimens and in vitro samples were sectioned buccolingually and mesiodistally, and marginal adaptation was evaluated at both proximal and occlusal margins at 200x magnification under a light microscope. The data was analyzed with anova (P < 0.05). The in vivo mean film thickness values for occlusal and proximal locations were recorded as 73 and 132 microm respectively. In vitro mean marginal fit values were observed as 48 and 67 microm for occlusal and proximal margins of inlays luted with Variolink II high viscosity. The marginal fit values recorded under in vivo conditions were higher in magnitude than the measurements obtained under in vitro conditions. The use of a highly filled resin luting agent with an ultrasonic insertion technique did not cause an increase in marginal gap width of the inlay.     

Marginal and internal adaptation of Class II ormocer and hybrid resin composite restorations before and after load cycling

To overcome the shortcomings of the conventional composite restorative materials, ormocer materials have been introduced over the past few years. The purpose of this study was to evaluate the marginal and internal adaptation of two ormocer restorative systems (Admira, Voco and Definite, Degussa) compared to a hybrid composite one (TPH Spectrum, Dentsply/ DeTrey), before and after load cycling in Class II restorations. Standardized Class II restorations with cervical margins on enamel were divided into three groups (n=16). Teeth of each group were filled with one of the restoratives tested and its respective bonding agent. Each group was divided into two equal subgroups. The marginal and internal adaptation of the first subgroup was evaluated after 7-day water storage at room temperature and of the second after cyclic loading in a mastication simulator (1.2×10⁶ cycles, 49 N, 1.6 Hz). The occlusal and cervical marginal evaluation was conducted by videomicroscope and ranked as excellent and not excellent. One thin section (150 m), in mesial-distal direction, of each restoration, was examined under metallographic microscope to determine the quality of internal adaptation. The occlusal and cervical adaptation of both ormocer restorative systems was similar and clearly worse compared with the hybrid composite restorative one before as well as after load cycling. Concerning internal adaptation, no gap-free ormocer restorations were detected, whereas all Spectrum restorations presented perfect adaptation. The bonding agents of the ormocers formed layers with unacceptable features (pores, fractures) whereas that of the hybrid composite achieved perfect bonding layer even after loading. The rheological characteristics of the bonding agents of the ormocer restorative systems are proposed to be responsible for their inferior marginal and internal quality in Class II restorations compared with the hybrid composite one.     

A 5-year clinical study of indirect and direct resin composite and ceramic inlays.

OBJECTIVE: The aim of this investigation was to evaluate the clinical performance of 4 types of tooth-colored inlays. METHOD AND MATERIALS: Fifteen direct ceramic inlays (Cerec Cos 2.0), 15 direct resin composite inlays (Brilliant Direct Inlay), 14 indirect ceramic inlays (Vita Dur N), and 14 indirect resin composite inlays (Estilux) were made in 37 patients, according to the manufacturers' instructions. The inlays were evaluated 1 week (baseline) and 6, 12, 36, 48, and 60 months after cementation (modified CDA Quality Evaluation System). RESULTS: Two Vita Dur N inlays fractured after 1 and 4 years in function, and one Cerec inlay fractured after 4.5 years. Two Brilliant DI inlays needed replacement because of secondary caries (after 1 and 5 years), and one inlay (Estilux) needed replacement due to persisting hypersensitivity. Three inlays (1 Estilux and 2 Brilliant DI) were repaired due to chipping or minor fractures. During the observation period, the surface texture of Brilliant DI and Vita Dur N inlays became significantly rougher. After 5 years, the Estilux inlays had significantly lower ratings for morphology compared to baseline ratings. In general, the occlusal marginal adaptation did not show further disintegration of the luting cement after 1 year. CONCLUSION: Eighty-eight percent of the inlays were in function after 5 years. No significant differences were revealed among the survival rates of the different types of inlays.