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| Title |
Bulk-fill Resin Composites Can Potentially Be as Effective as Conventional Composite Restorations Even In Class 2 Preparations |
| Clinical Question |
Will bulk-fill resins reduce marginal gap formation and, hence, potentially present fewer recurrent carries than layered conventional composite restorations even in patients with Class 2 preparations? |
| Clinical Bottom Line |
Using the more convenient bulk-fill resins could potentially be as effective as incremental conventional composite restorations even in class 2 preparations, but additional clinical evidence, especially long-term efficacy studies, is needed to validate laboratory findings. |
| Best Evidence |
(you may view more info by clicking on the PubMed ID link) |
| PubMed ID |
Author / Year |
Patient Group |
Study type
(level of evidence) |
| #1) NA | Tiba/2013 | NA | Laboratory study | | Key results | ADA Professional Product Review, 2013 Volume 8 issue 3, page 13
http://www.ada.org/en/publications/ada-professional-product-review-ppr/archives/2013
Depth of Cure: Only 6 of the 10 bulk filled resin composites met or exceeded the manufacturer’s claimed depth of cure of between 4-5 mm.
6 of the 11 had significantly higher mean depth of cure than 4.0 mm.
Volumetric shrinkage: Only three of the 10 bulk filled resin composites showed lower volumetric shrinkage than both incrementally cured traditional resin based composite controls (p<0.05). Five bulk filled resin composites actually showed higher volumetric shrinkage than both incrementally cured traditional resin based composite controls (p<0.05)
Polymerization shrinkage stress: Only one of the 10 bulk filled resin composites had significantly lower polymerization shrinkage stress (Sonic Fill) than the 2 incrementally filled resin composite controls (p<0.05). One of the bulk filled resin composites actually had higher polymerization shrinkage stress (X-trabase) than the incrementally filled resin composite controls (p<0.05).
Mechanical properties: All composites exceeded the minimum flexural strength requirement according to ISO standards. However, nine of the 10 bulk filled resin composites were nonetheless significantly weaker than the Filtek Supreme control. Eight of the 10 bulk filled resin composites did have significantly higher fracture toughness than the controls.
Water sorption and solubility. All bulk filled resin composites had significantly lower water sorption and solubility than the two controls.
| | #2) 12974860 | Idriss/2003 | NA | Laboratory study | | Key results | Idriss in a 2 by 2 study compared bulk vs incremental filling and a chemical curing composite (Rapidfil) and a light cured composite (Amelogen) found no statistical difference in mean marginal gaps for placement type (bulk vs. incremental). However, the chemically cured composite Rapidfil had fewer margin gaps than Amelogen (p<0.05). It is not certain that in 2003, Rapidfil was marketed as a bulk-filled resin nor is it clear that the authors were aware of it as a bulk-filled resin, but the authors realized that, as a chemically-cured composite, the shrinkage stress would probably be significantly lower than an light-cured resin. As such, they explored its use in bulk-filling cavities. | | #3) 24480086 | Furness/2014 | NA | Laboratory study | | Key results | As stated in Furness:
“No significant differences in gap-free margins were found between placement method within a given product per location. Except for SDR, percentage of gap-free margins was significantly lower at the pulpal floor interface than at the enamel interface for bulk-fill.” However, sample sizes were only n=5 and the error bars were very large, bringing to question these conclusions.
| | #4) NA | Roggendorf/ 2011 | NA | Laboratory study | | Key results | The presence of 4mm Surefil intermediate layer showed no statistically significantly difference in percentage of gap-free margins than the controls that were placed incrementally across all 5 resin composites used (p<0.05). The only difference in marginal gap formation was due to the choice of adhesive used: etch-and-rinse vs. self-etch. | | #5) 25625133 | van Dijken/2015 | 44 male and 42 female adults, 38 pairs (76 total) class 1 62 pairs (124 total) class 2 restorations | Randomized Controlled Trial | | Key results | Upon evaluation of 122 class 2 and 74 class 1 restorations at the 3-year mark, a total of 7 restorations had failed all of which were class 2. Average failure rate for the class 2 restorations was 2.2% for the bulkfilled (sandwiched) restorations and 1.6% for the resin composite-only restorations. None of the failed restorations were due to secondary caries. | |
| Evidence Search |
"bulk"[All Fields] AND fill[All Fields] AND composite[All Fields] OR bulk-fill[All Fields] |
Comments on
The Evidence |
Tiba/2013: The clinical relevance of Polymerization shrinkage stress and volumetric stress are in theory correlated to improved prevention of recurrent caries but appropriate clinical trials need to be performed to help illuminate these variables. Six of the 10 bulk filled resin composites met or exceeded manufacturer’s claimed depth of cure of between 4-5 mm. In addition, only one (X-trabse)) had significantly higher polymerization shrinkage stress than controls. Thus, it can be assumed that most bulk filled resins will cure well throughout the 4-5 mm depth and produce similar shrinkage stress to conventional composites that are placed in increment layers.
Idriss/2003:
One of the more interesting things to note on this study is the statistically significant higher performance of the chemically activated product over the light activated product in reducing marginal gap formation. This most probably is due to the reduced shrinkage stress generated by the slower curing mechanism of in a chemically-cured resin. This validates the use of bulk filling resins, especially if it is chemically cured.
Furness/2014: There is not a significant difference in gap-free margins due to placement technique (bulk vs incremental) at a given location but there is a significant increase in gap-free margins between the pulpal floor and the enamel except in Surefil SDR where there was no difference. This may be due to the flowability of Surefil SDR better adapting to the shape of the pulpal floor.
Roggendorf/2014: In this study the investigators used one of the flowable resin composites present in three of the studies reviewed (Surefil SDR) and used the sandwich technique and found no statistically significantly difference in percentage of gap-free margins when compared to incrementally cured composites. Instead the only difference in marginal gap formation was due to the choice of adhesive with “etch and rinse” or a third generation system havin statistically significant higher gap-free margins than when a self-etching adhesive system is used. Thus, it seems that the use of a bulk filled composite, even a flowable bulk-filled composite, such as Surefil SDR, as a 4-mm base is not detrimental.
van Dijken/2015:
This study shows that bulk-filled flowable resins, such as Surefil SDR, can be used in the closed sandwich technique in class II restorations effectively. However, the average annual failure rate of 2.2% for bulk-filled resins in class II restorations vs. 1.6% in conventional preparations is slightly concerning. Thus, longer term studies for the effectiveness of bulk-filled resins is needed.
|
| Applicability |
The 4mm cure depth of the new bulk filled resin composite resins being claimed by many products is an advantage that some dental practitioners are gravitating towards. Laboratory testing shows that most bulk-filled resins are mechanically equivalent to conventional resins and the shrinkage stress generated in a bulk-filling situation is also equivalent to that of incrementally-placed conventional restorations. Thus, it seems that these new resins can be used in place of conventional restoratives, even in class II situations. However, the average annual failure rate of 2.2% for bulk-filled resins in class II restorations vs. 1.6% in conventional preparations is slightly concerning. Thus, longer term studies for the effectiveness of bulk-filled resins is needed. |
| Specialty/Discipline |
(Restorative Dentistry) |
| Keywords |
Bulk cure resin composites, Resin Composites, Bulk-fill resin composites,
|
| ID# |
2903 |
| Date of submission: |
04/08/2015 |
| E-mail |
bernalc4@livemail.uthscsa.edu |
| Author |
Carlos A. Bernal |
| Co-author(s) |
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| Co-author(s) e-mail |
|
| Faculty mentor/Co-author |
Niraj K. Patel, DDS & Kyumin Whang, PhD |
| Faculty mentor/Co-author e-mail |
WHANG@uthscsa.edu; patelnk@livemail.uthscsa.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?) |
post a rationale |
| None available | |
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Comments and Evidence-Based Updates on the CAT
(FOR PRACTICING DENTISTS', FACULTY, RESIDENTS and/or STUDENTS COMMENTS ON PUBLISHED CATs) |
post a comment |
| None available | |
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