Title For Patients Requiring Posterior Class II Restorations with Gingival Terminations in Dentin, Glass Ionomer Provides Superior Marginal Adaptation Compared to Resin-based Composite
Clinical Question Which adhesive material has better marginal adaptation in preventing microleakage in posterior Class II composite restorations with gingival margins within dentin, modified glass ionomers or resin-based composites?
Clinical Bottom Line Microleakage continues to be a challenge in adhesive dentistry when margins are within dentin. Based on the results of these studies, one can conclude that, in general, glass ionomer offers improved marginal seal over resin-based composite at gingival terminations.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
17439712Stockton/200750 extracted molars with mesio-occlusal and distal-occlusal preparationsIn vitro comparative study
Key resultsThis study compared the efficacy of Vitrebond (resin-modified glass ionomer base) using the closed-sandwich technique, Geristore (compomer) using the open-sandwich technique, a control group and other adhesive materials to determine which material resulted in the least microleakage and better marginal adaptation. Class II cavity preparations on 50 extracted mandibular and maxillary molars were randomly assigned into 5 test groups and treated. The data was analyzed using ANOVA and Tukey’s test to determine significance with a p value ≤ 0.05. These results showed statistically significant reductions in leakage with margins in dentin when using resin-modified glass ionomer and Clearfil SE Bond in a closed-sandwich technique. The investigators also deduced that since resin-modified glass ionomer has a lower Young’s modulus and better flow characteristics during maturation than highly filled resin-based composites, this would result in less shrinkage stress during polymerization offering perhaps even better marginal adaptation and potentially less microleakage.
10071469Dietrich/1999120 extracted human molars with large butt-joint Class II cavity preparationsIn vitro comparative study
Key resultsThe authors of this study compared the marginal adaptation of direct Class II sandwich restorations with resin-modified glass ionomer cements and compomers to base and total bond restorations. Large butt-joint Class II with cervical margins 1 mm below the CEJ were prepared on 120 extracted human molar teeth and divided into groups of 15 (n=8). The data was analyzed using Kruskal-Wallis test and Bonferroni to correct for pairwise comparison with a significance level of p < 0.05 and revealed that there were no significant differences between base and total bond restorations or both techniques; however, for margins in dentin, marginal adaptation was significantly better with the sandwich technique than with base or total bond technique for all materials. Overall, the use of resin-modified glass ionomer cements showed better results than compomers for most criteria.
12120714Anderson-Wenckert/200240 Class II restorations placed in 20 premolars scheduled for orthodontic extraction after 1 month in 10 patientsRandomized controlled clinical simulation
Key resultsIn this study, one dentist placed 40 box-shaped Class II resin-modified glass ionomer cement (RMGIC)/resin composite (RC) in 20 premolar teeth scheduled for orthodontic extraction after one month in 10 patients. Its aim was to evaluate the interfacial adaptation to enamel and dentin of various modified Class II open RMGIC/RC restorations as well as the influence of different light curing techniques and matrix bands in vivo. The prepared cavities were randomly assigned to one of five groups restored with various techniques, materials, light curing techniques and matrices. After 1 month of function in the mouth, the experimental premolars were extracted, sectioned and prepared; analysis was conducted using multivariate, bivariate non-parametric, Mann-Whitney and Exact tests on non-paired data and Wilcoxon signed-rank test on paired data with tests carried out at 5% level of significance. Overall, the results showed that there were no significant differences in gap-free adaptation to enamel or dentin between all 5 experimental groups but adaptation to enamel was significantly better in closed versus open sandwich restorations (p = 0.04) with no significant differences found in dentin. Different curing and application techniques did not influence the interfacial adaptation. At the cervical margins however, RMGIC showed significantly better adaptation to enamel than RC (p = 0.02).
Evidence Search Marginal adaptation, marginal seal, composite, glass ionomer, deep Class II restorations
Comments on
The Evidence
Most of the studies reviewed were performed on extracted teeth in a controlled laboratory setting, the results of which cannot be adequately reliable in the oral environment in a clinical setting. More clinical studies are necessary in this regard. Although many of our search results with our specific criteria included studies that included compomers, it is important to note that the use of compomers is no longer popular; however, the relevance of resin-modified glass ionomers with varying techniques is current and may be considered for practical application.
Applicability The results of these studies indicate that there is evidence to suggest that the use of glass ionomers in a closed sandwich technique when margins are in dentin offer significantly improved marginal adaptation with less microleakage; however, there is a need for more research to determine best methods, techniques and materials to achieve optimal marginal seal with clinical long-term trials.
Specialty (General Dentistry) (Restorative Dentistry)
Keywords Microleakage, marginal adaptation, composite, glass ionomer
ID# 2597
Date of submission 11/08/2013
E-mail helen.oboro-onuora@ucdenver.edu
Author Helen Oboro-Onuora
Co-author(s) e-mail
Faculty mentor Christina J. Lee, DMD, DDS
Faculty mentor e-mail christina.j.lee@ucdenver.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available