Effect of a Resin Coating Material on the Microleakage of Class V Restorations With or Without Post-Operative Bleaching

Abstract

To evaluate the effect of a resin coating material on the microleakage of Class V composite resin restorations with and without post-operative bleaching. Material and Methods: Eighty class V cavities (3×3×1.5 mm) were prepared and filled with Z250 XT composite resin in the buccal and lingual surfaces of 40 sound human molars. Then the samples were randomly divided into 4 groups (n=20) and treated as follows: Group A: applying a resin coating (G-Coat Plus) on the restoration, then bleaching with 40% hydrogen peroxide; Group B: Post-Operative bleaching without prior use of resin coating; Group C: applying resin coating agent, and no further bleaching; and Group D: no resin coating, no bleaching. The specimens were thermocycled and immersed in 1% methylene blue for 24 hours, then cut into sections bucco-lingually. The samples were scored regarding the amount of dye penetration under a stereomicroscope (x20). Data were analyzed with Chi-squared and Fisher exact tests (p<0.05). Results: The maximum gingival and occlusal microleakage was detected in group B, while the minimum was seen in group C. In all the groups, microleakage at gingival margins was higher than occlusal margins (p<0.001). Conclusion: Application of a resin coating is an effective method in reducing microleakage of the restorations before and after bleaching.

Effect of at-home and in-office bleaching on microleakage of class V composite resin restorations using different types of universal adhesives: An in vitro study

“…Therefore, it is easily affected by the chemicals in bleaching agents. Hajilou et al 18 investigated the effect of 40% hydrogen peroxide bleaching on the microleakage of composite resin restorations, reporting that bleaching after restoration increases the microleakage, with significantly greater microleakage in gingival margins.…”

Comparative Evaluation of Surface Roughness of Resin- Modified Glass Ionomer and Glass Hybrid Restorative Materials Simulated by Tooth Brushing: An in-Vitro Study

“…A protective coating either with light polymerized low viscosity unfilled resin adhesives or G-coat plus is compulsory for all the glass ionomer materials to enhance the wear resistance [23,24]. Conversely, some studies reported no difference in surface roughness values in coated and uncoated specimens [14].…”

Microleakage and Marginal Integrity of Surface-Coated and Laser-Pretreated Class V Composite Restorations in Primary Teeth

“…3,5,6 Microleakage is clinically associated with staining around the restoration margins, postoperative sensitivity, secondary caries, pulpal pathology, lower bond strength, and the subsequent partial or total failure of the restoration. 7 Since restoration durability highly depends on the integrity and longevity of the marginal seal, various methods and compensatory mechanisms have been tried to decrease the marginal gap at the tooth-restoration interface. 8 As a novel recommended technique, surface coating materials can be applied on the finished restoration cavosurface margins to penetrate the marginal gaps and structural microdefects by capillary action, thereby enhancing the marginal seal of esthetic restorative materials.…”

“…3 Coating materials are said to bond strongly with enamel, composite, dentin, ionomer, glass and resin-modified glass ionomers. 7 G-Coat Plus is a methyl methacrylate-based photopolymerized resin-based coating material with low viscosity that is filled with nanofillers for better wear resistance. 9 In permanent teeth, coating restores the marginal integrity and reduces the gingival microleakage in Class V restorations at enamel and dentin margins.…”