Effect of Light Curing Units on Marginal Adaptation and Hardness of Class II Composite Resin Restorations

Abstract Aims The aim of this study was to test the influence of different curing protocols on dentin marginal adaptation and the hardness of two composites. Methods and Materials Three light-curing-units (LCUs): Quartz-Tungsten-Halogen (QTH: 541mW/cm2), Argon-Ion-Laser (AL: 277mW/cm2), and Plasma-Arc-Curing (PAC: 1818mW/cm2) and two composites FiltekZ250 (F) and Tetric Ceram HB (TC) were tested. Sixty standardized “vertical-slot-Class II-cavities” were prepared at the mesial surface of bovine incisors and divided into six groups (n=10). Composites were placed using the Single Bond adhesive system and cured in 2 mm increments according to the manufacturers’ instructions. After polishing, epoxy replicas were processed for scanning electron microscopy (SEM) marginal adaptation analysis at 500x magnification. The specimens were then sectioned transversally to the dental long axis, embedded in polyester resin, then polished and submitted to the Knoop hardness test at gingival and occlusal portions of the restoration. Data were analyzed using two-way analysis of variance (ANOVA) and Tukey's test (p=0.05). Results The gap margins ranged between 4.3 to 5.8 μm, and no statistically significant differences were revealed in marginal adaptation for LCUs or for composites (p>0.05). Location influenced hardness (p≤0.01). The occlusal portion presented significantly higher KHN than the gingival portion for all composite-LCU combinations. Regardless of the LCU used, TC produced statistically significant lower hardness values (ranging between 82.8 to 110.7 KHN) than F (ranging between 105.9 to 117.3 KHN). Conclusions Hardness and gap formation were not dependent on the LCUs tested in this study. Different resin composite was found to be a significant factor with regards to hardness but not gap formation. Citation Cavalcante LM, Peris AR, Silikas N, Pimenta LAF. Effect of Light Curing Units on Marginal Adaptation and Hardness of Class II Composite Resin Restorations. J Contemp Dent Pract 2007 November; (8)7:038-045.

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BULKFILL TECHNIQUES WITH INTERMEDIATE LAYER TO MARGINAL ADAPTATION RESTORATION OF CLASS II COMPOSITE RESIN

Conservative Dentistry Journal ◽

10.20473/cdj.v11i1.2021.32-37 ◽

2021 ◽

Vol 11 (1) ◽

pp. 32

Author(s):

Mochammad Raidjffan Zulkarnaen Tabona ◽

Adioro Soetojo ◽

Ira Widjiastuti

Keyword(s):

Dental Caries ◽

Intermediate Layer ◽

Composite Resin ◽

Class Ii ◽

Base Layer ◽

Marginal Adaptation ◽

Layer Technique ◽

Natural Teeth ◽

Composite Resin Restorations ◽

Resin Restorations

Background: Dental caries is a hard tissue disease caused by bacterial metabolic activity that causes demineralization, teeth that have caries should be filled in order to function again. One of the restorative materials closer to natural teeth is composite resin because it is the same colour as natural teeth and is easy to shape. As for the placement technique, bulkfill is also used because it is more time-efficient, and irradiation is accompanied by applying the restoration material in one batch. However, the bulkfill technique often causes micro-leakage of dental caries deposition. The intermediate layer is an intermediate layer used to prevent micro-leakage at the edges of the restoration as a base layer for restoration to create a good adaptation before applying packable composite resin. Therefore, bulkfill coating technique with the intermediate layer can reduce the risk of microleakage. Purpose: To describe the bulkfill technique with an intermediate layer against marginal adaptation with class II composite resin restorations. Review: The literature sources used in the preparation of the articles through several databases with descriptions. More journals say that micro-leakage in class II cavity deposition with the intermediate layer technique is better than the bulkfill technique because the intermediate layer technique has better bond strength than the bulkfill technique. If the Bulkfill technique is modified with the Intermediate layer technique, it can show good correlation and internal adaptation. Conclusion: Bulkfill technique with an intermediate layer against marginal adaptation with class II composite resin restorations can reduce the microleakage rate by reducing the polymerization's shrinkage strain.

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The Influence of Different Base Materials on Marginal Adaptation of Direct Class II Composite Resin Restorations

Advanced Biomaterials VI - Key Engineering Materials ◽

10.4028/0-87849-967-9.481 ◽

2005 ◽

pp. 481-484

Author(s):

Sung Ho Park ◽

Yon Sang Cho ◽

I.Y. Jung ◽

Kwon Yong Lee ◽

S.B. Jeon

Keyword(s):

Composite Resin ◽

Class Ii ◽

Marginal Adaptation ◽

Base Materials ◽

Composite Resin Restorations ◽

Resin Restorations

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Effect of Centripetal and Incremental Methods in Class II Composite Resin Restorations on Gingival Microleakage

The Journal of Contemporary Dental Practice ◽

10.5005/jcdp-8-2-113 ◽

2007 ◽

Vol 8 (2) ◽

pp. 113-120 ◽

Cited By ~ 8

Author(s):

Horieh Moosavi ◽

Marjaneh Ghavamnasiri ◽

Najmeh Tahvildarnejad

Keyword(s):

Composite Resin ◽

Resin Composite ◽

Class Ii ◽

Incremental Methods ◽

Maxillary Premolars ◽

Recorded Data ◽

The Mean ◽

Composite Resin Restorations ◽

Parametric Statistical Test ◽

Resin Restorations

Abstract Aim The aim of this study was to evaluate the microleakage at gingival margins below the cementoenamel junction (CEJ) of Class II composite restorations using various placement techniques. Methods and Materials Sound human maxillary premolars were selected. Eighty slot-style cavities on the mesial or distal surfaces were prepared with the cervical margins located apical to the CEJ. The specimens were divided into two groups based on the restorative technique utilized (centripetal or incremental). Each group was then categorized into two subgroups according to the type of matrix used resulting in a total of four experimental groups as follows: IP=Incremental and Palodent matrix, IT = Incremental and Transparent matrix, CP = Centripetal and Palodent matrix, and CT = Centripetal and Transparent matrix. Following restoration with a total etch adhesive (Single Bond) and a resin composite (Z100), the teeth were thermocycled. Then specimens were immersed in 0.5% basic fuchsin dye for 24 hours at a temperature of 37°C. Sectioned restorations were examined under a stereomicroscope (40X magnification), and the extent of the microleakage was scored and recorded. Data were analyzed using the Kruskal-Wallis non-parametric statistical test (P=0.05). Results In the four groups of the study no significant differences in the mean rank of microleakage were observed (p>0.05). Conclusion When the gingival margin was located on cementum, the kind of matrix and filling technique did not reduce the microleakage. Citation Ghavamnasiri M, Moosavi H, Tahvildarnejad N. Effect of Centripetal and Incremental Methods in Class II Composite Resin Restorations on Gingival Microleakage. J Contemp Dent Pract 2007 February;(8)2:113-120.

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