Effect of Photoactivation Systems and Resin Composites on the Microleakage of Esthetic Restorations

2007 ◽  
Vol 8 (2) ◽  
pp. 70-79 ◽  
Author(s):  
Gláucia Maria Bovi Ambrosano ◽  
Larissa Maria Assad Cavalcante ◽  
Alessandra Resende Peris ◽  
André Vicente Ritter ◽  
Luiz André Freire Pimenta

Abstract Aim The aim of this study was to evaluate the influence of four photoactivation systems [quartz tungsten halogen (QTH), light-emitting diode (LED), argon ion laser (AL), and plasma arc curing PAC)] on cementum/ dentin and enamel microleakage of Class II restorations using a microhybrid [Z250 – 3M ESPE] and two packable composites [(SureFil - Dentsply and Tetric Ceram HB – Ivoclair/Vivadent]. Methods and Materials Three hundred sixty “vertical-slot Class II cavities” were prepared at the mesial surface of bovine incisors using a 245 carbide bur in a highspeed handpiece. Specimens were divided into twelve groups (composite-photoactivation systems). Half of the specimens had the gingival margin placed in enamel (n=15) and the other half in cementum/dentin (n=15). Composites were inserted and cured in 2 mm increments according to manufacturers’ recommended exposure times. After polishing, the samples were immersed in 2% methylene blue solution, sectioned, and evaluated at the gingival margins. Data were submitted to statistical analysis using the Kruskal–Wallis and Mann-Whitney tests. Results No significant differences were found among the photoactivation systems and among resin composites (p>0.05). Microleakage was not significantly affected by location (enamel vs. cementum/dentin, p>0.05). These findings suggested neither the photoactivation systems nor the resin composite types might have an effect on the microleakage at gingival margins Class II cavities. Citation Cavalcante LMA, Peris AR, Ambrosano GMB, Ritter AV, Pimenta LAF. Effect of Photoactivation Systems and Resin Composites on the Microleakage of Esthetic Restorations. J Contemp Dent Pract 2007 February;(8)2:070-079.

2010 ◽  
Vol 04 (04) ◽  
pp. 440-446 ◽  
Author(s):  
Isil Cekic-Nagas ◽  
Ferhan Egilmez ◽  
Gulfem Ergun

Objectives: The aim of this study was to compare the microhardness of five different resin composites at different irradiation distances (2 mm and 9 mm) by using three light curing units (quartz tungsten halogen, light emitting diodes and plasma arc).Methods: A total of 210 disc-shaped samples (2 mm height and 6 mm diameter) were prepared from different resin composites (Simile, Aelite Aesthetic Enamel, Clearfil AP-X, Grandio caps and Filtek Z250). Photoactivation was performed by using quartz tungsten halogen, light emitting diode and plasma arc curing units at two irradiation distances (2 mm and 9 mm). Then the samples (n=7/ per group) were stored dry in dark at 37°C for 24 h. The Vickers hardness test was performed on the resin composite layer with a microhardness tester (Shimadzu HMV). Data were statistically analyzed using nonparametric Kruskal Wallis and Mann-Whitney U tests.Results: Statistical analysis revealed that the resin composite groups, the type of the light curing units and the irradiation distances have significant effects on the microhardness values (P<.05).Conclusions: Light curing unit and irradiation distance are important factors to be considered for obtaining adequate microhardness of different resin composite groups. (Eur J Dent 2010;4:440-446)


Author(s):  
Anuradha Vitthal Wankhade ◽  
Sharad Basavraj Kamat ◽  
Santosh Irappa Hugar ◽  
Girish Shankar Nanjannawar ◽  
Sumit Balasaheb Vhate

Introduction: New generation composite resin materials have revolutionized the art of aesthetic dentistry. The clinical success is dependent on effective polymerisation and surface hardness which in turn are dependent on the performance of Light Curing Units (LCU). This study utilises surface hardness as a measure of degree of polymerisation of composite resins achieved by LCUs. Aim: To evaluate the difference in surface hardness of nanohybrid and microhybrid resin composites cured by light curing systems, Light Emitting Diode (LED) and Quartz Tungsten Halogen (QTH). Materials and Methods: In this invitro experimental study, two types of hybrid composites (Nanohybrid and Microhybrid) were tested for surface hardness by using two different light curing systems (LED and QTH). All the Nanohybrid and Microhybrid specimens were cured using LED and QTH LCUs, thus giving four combinations. A total of 60 specimens (6 mm diameter and 2 mm depth) were prepared using Teflon mould with 15 samples for each combination. Surface hardness was measured on upper and lower surface after 24 hours and hardness ratio was calculated. Data was analysed using independent t-test for intergroup comparison. Level of significance was kept at 5%. Results: Surface hardness of resin composites cured by LED LCU was greater than those cured by QTH LCU. Additionally, the hardness value was greater for the upper surface. Nanohybrids showed better surface hardness than Microhybrids for both the LCUs. Conclusion: Nanohybrid composite resins and LED system were found to be more effective in terms of surface hardness as compared to their counterparts.


2015 ◽  
Vol 40 (1) ◽  
pp. 19-24 ◽  
Author(s):  
MJMC Santos

SUMMARY This clinical report describes a restorative technique used to replace two Class II resin composite restorations on the upper premolars. A sectional matrix band was used in conjunction with an elastic ring (Composi-Tight) to obtain tight proximal contact. A nanofilled resin composite (Filtek Supreme Ultra) was incrementally applied using oblique layers to reduce the C-factor, each layer being no more than 2 mm thick, and then light cured for 20 seconds with a light-emitting diode lamp (EliparFreeLight 2 LED Curing Light) with a power density of 660 mW/cm2. A centripetal technique was used to restore the lost tooth structure from the periphery toward the center of the cavity in order to achieve a better contour and anatomy with less excess, thereby minimizing the use of rotary instruments during the finishing procedures. Finally, the resin composite restorations were finished and polished, and a surface sealer (Perma Seal) was applied to fill small gaps and defects that may have been present on the surfaces and margins of the restorations after the finishing and polishing procedures.


2007 ◽  
Vol 32 (5) ◽  
pp. 443-450 ◽  
Author(s):  
M. G. Brackett ◽  
W. W. Brackett ◽  
W. D. Browning ◽  
F. A. Rueggeberg

Clinical Relevance The selection of light curing unit (quartz-tungsten-halogen or blue light-emitting diode), composite classification and shade have an influence on the amount of residual yellow after photocuring and, in some combinations, the color difference may be visually detectable.


2015 ◽  
Vol 40 (3) ◽  
pp. 271-281 ◽  
Author(s):  
C Sabatini

SUMMARY Despite significant developments in improving the optical properties of resin composite materials, their color stability remains a challenge. This study aimed to evaluate the shade stability of light-polymerized, methacrylate-based resin composites with different filler particle composition (microfill, minifill, nanohybrids, and microhybrids) polymerized with quartz-tungsten-halogen (QTH) and light-emitting diodes (LED). Methods and Materials Composite discs were fabricated from Tetric EvoCeram, Premise, Artiste, and Beautifil II (nanohybrids); Filtek Supreme Plus and Vit-l-escence (microhybrids); Heliomolar (microfill); and Estelite Sigma Quick (minifill) using a Teflon mold. The specimens were irradiated either with QTH (Elipar 2500; 600 mW/cm2) for 40 seconds or with LED (Bluephase G2; 1200 mW/cm2) for 20 seconds. Color parameters were measured with a colorimeter before and after polymerization and at 24 hours, one week, one month, and three months. Color change was calculated among the different storage periods. Results There was a significant effect of the composite, time, and their interaction (p&lt;0.001) but no effect of the polymerization unit on the color stability. Color changes immediately after polymerization and at 24 hours (4.22 and 3.88 for LED; and 4.08 and 3.82 for QTH) were not significantly different from each other but were both significantly higher than changes after one week (0.96 and 0.78), one month (1.12 and 1.02), and three months (1.27 and 1.11) for LED and QTH, respectively (p&lt;0.001). Conclusions Color changes were observed for all the materials that were dependent on the type of composite but not on the polymerization unit. These color shifts took place primarily immediately after polymerization and after 24 hours and were additive in nature.


2012 ◽  
Vol 24 (2) ◽  
Author(s):  
Esther Bianca ◽  
Milly Armilia Andang ◽  
Endang Sukartini

Introduction: Adequate surface hardness of the resin composites is important to obtain optimum clinical performance of the restoratives in stress dental bearing areas. For light-activated resin composites, polymerization begins when curing light initiates polymerization and continues after the curing light goes off. The degree of conversion and hardness of resin composite is also affected by post-irradiation time. The objective of this study was to evaluate the difference of the hardness hybrid resin composite based on post-irradiation time at 10 minutes, 24 hours, and 7 days with photoactivated light-emitting diode (LED) to obtain the optimum hardness. Methods: This study was using a true experimental research method. Thirty samples of hybrid resin composites, disk-shaped of 6 mm in diameter and 2 mm in depth were polymerized by LED LCU at 800mW/cm2 for 20 seconds. The hardness of the resin composite was measured by Vickers Hardness Tester. The result was analyzed statistically with ANOVA. Results: There was a significant difference level of hardness among the three groups. Hardness mean value for post-irradiation time at 10 minutes was 56,4 VHN, for post-irradiation time at 24 hours was 65,8 VHN, and for post-irradiation time at 7 days was 60,0 VHN. Conclusion: There were differences level of hybrid resin composite’s hardness based on the post-irradiation time at 10 minutes, 24 hours, and 7 days with photoactivated LED and the optimum hardness of post-irradiation time at 24 hours.


2021 ◽  
Author(s):  
MD Moda ◽  
AF Briso ◽  
IAE Hoshino ◽  
SMB Frascino ◽  
PH Santos ◽  
...  

SUMMARY Objectives: This randomized, prospective, and split-mouth study aimed to evaluate flowable bulk-fill resin composites in class II restorations and to compare with a conventional layering technique after a 3-year follow-up. Methods and Materials: Fifty-three subjects received three class II restorations according to the restorative systems: conventional microhybrid resin composite (PA, Peak Universal + Amelogen Plus, Ultradent), flowable bulk-fill and nanoparticulate resin composites (ABF, Adper Single Bond 2 + Filtek Bulk Fill Flow + Filtek Z350XT, 3M Oral Care), and flowable bulk-fill and microhybrid resin composites (XST, XP Bond + SDR + TPH3, Dentsply). The clinical performance and interproximal contacts were evaluated. Statistical analyses were performed using the equality test of two proportions, Logistic regression analysis, Friedman, Wilcoxon, Kruskal-Wallis, and Mann-Whitney tests (α=0.05). Results: Forty-seven patients were evaluated at 3 years. XST bulk-fill restorative system presented higher marginal discoloration than PA, and the opposite occurred for surface staining. All restorative systems resulted in decreased interproximal contacts, occurring early for XST. Conclusions: Although the restorative system using incremental technique presented better performance for marginal discoloration, one of the restorative systems that used flowable bulk-fill resin composite (XST) showed the lowest surface staining. All restorative systems had decreased proximal contact over time.


Sign in / Sign up

Export Citation Format

Share Document