A double-blind, split-mouth randomized trial published online in the Journal of Dentistry on October 28, 2026 found that a one-shade flowable composite performed comparably to a multi-shade flowable in non-carious cervical lesions over 18 months. Retention was 98.4% versus 100%, with no significant difference, and spectrophotometer colour measurements did not differ significantly. Visual colour-match scores, however, favoured the multi-shade material at 18 months, although every restoration assessed for colour match stayed clinically acceptable.
Shade selection is one of the small chairside steps that adds up across a busy restorative day. One-shade composites promise to remove it. As of October 2026, a new multicentre trial from Brazil puts that promise to a clinical test in non-carious cervical lesions (NCCLs). For practices in Toronto and across the GTA weighing whether to simplify their composite inventory, the results are encouraging, with one caveat that matters for aesthetics.
What did the trial compare?
The study, titled "One-shade versus multi-shade flowable composites for non-carious cervical lesions: color match and 18-month clinical performance in a double-blind, split-mouth randomized trial," was conducted by researchers from the State University of Ponta Grossa, the University of São Paulo, the Federal University of Santa Catarina and the Federal University of Paraná. It appears in the Journal of Dentistry as article 107139.
The authors compared two flowable composites, both made by FGM:
- Vittra APS Unique Flow, a one-shade flowable composite
- Opallis Flow, a multi-shade flowable composite
According to the abstract, 124 NCCLs were restored in 62 participants, giving 62 restorations per material. The design was randomized, split-mouth and multicentre, which means each participant received both materials. That design controls for patient-level factors such as diet and oral hygiene, since every person acts as their own comparison.
How was colour measured?
The trial looked at colour two ways, and the distinction is the most useful part of the paper for clinicians.
Objective colour: the spectrophotometer
The researchers used a spectrophotometer to calculate two colour-difference values (ΔEab and ΔE00). They made two comparisons at 7 days: the cervical third of the tooth before and after restoration, and the cervical third against the middle third after restoration. Neither comparison showed a significant difference between the one-shade and multi-shade materials.
Visual colour: the FDI criteria
Clinical performance was scored with FDI criteria at baseline and at 6, 12 and 18 months. These criteria cover functional, biological and aesthetic properties, including colour match as judged by an examiner. Here the picture shifted slightly. At 18 months, the multi-shade composite showed a higher frequency of "clinically excellent/very good" colour-match scores (p = 0.008). The authors note that all restorations evaluated for colour match remained clinically acceptable.
So the spectrophotometer found no significant difference at 7 days, while examiner-rated colour match at 18 months favoured the multi-shade material. For a cervical lesion on a lower premolar, that gap may never come up. For a high smile line on an upper canine, your patient may be the one doing the visual scoring.
Pro Tip: Photograph cervical restorations at placement and again at the 6-month recall under the same lighting. Two years of your own before-and-after images will tell you more about a material's colour stability in your patient base than any single trial.
What were the clinical results at 18 months?
Retention is the headline outcome for NCCL restorations, because these lesions offer limited mechanical retention and rely heavily on adhesion. According to the abstract:
- Retention at 18 months was 98.4% for the one-shade composite and 100% for the multi-shade composite, with no significant difference between materials.
- No significant differences were found for the remaining functional, biological or aesthetic FDI criteria, apart from colour match.
- The authors concluded that the one-shade flowable showed "favorable 18-month clinical performance."
The authors' stated clinical significance is that one-shade flowable composites "may simplify NCCL restorations by eliminating shade selection while maintaining favorable clinical performance and clinically acceptable color match."
What does this mean for dental practices in Ontario?
The appeal of a one-shade material for a general practice is practical. Fewer syringes on the tray, fewer partly used shades expiring in the drawer, and one less decision for the associate or new graduate who is still building confidence with shade matching. For multi-chair practices in Mississauga, Markham or Vaughan that try to standardize materials across operatories, that simplicity can be attractive.
This trial supports that approach for NCCLs specifically, over an 18-month window, with one product. Before you change your restorative inventory, keep the limits in view:
- One product pair. The study tested one one-shade flowable and one multi-shade flowable from the same manufacturer. Other one-shade composites use different formulations, and these results should not be read as a verdict on the whole category.
- One lesion type. NCCLs are a specific clinical situation. The findings do not tell you how a one-shade flowable performs in Class III or Class IV restorations, or in larger anterior cases.
- 18 months is mid-term. Retention and colour stability can change over longer periods, and this report stops at 18 months.
- Visual match did diverge. The only significant difference the authors found was in examiner-rated colour match, and it favoured the multi-shade material.
Pro Tip: If you trial a one-shade flowable, start with posterior and low-visibility cervical lesions, and keep your multi-shade system for aesthetic-zone cases until you have your own recall data.
Is Vittra APS Unique Flow available in Canada?
This report does not confirm Canadian availability or Health Canada licensing for either material in the study. A trial published in an international journal says nothing about whether a product is licensed or distributed here. Confirm Health Canada licensing status with your supplier before purchasing any material named in a clinical study, and check the Medical Devices Active Licence Listing (MDALL) if you want to verify it yourself.
EBIKO Dental will continue monitoring restorative materials research and what it means for practices across Toronto and the rest of Canada. You can browse current restorative supplies at ebiko.ca.
Sources
- Barbosa LMM, Favoreto MW, Cochinski GD, et al. One-shade versus multi-shade flowable composites for non-carious cervical lesions: color match and 18-month clinical performance in a double-blind, split-mouth randomized trial. Journal of Dentistry, article 107139, published online October 28, 2026. doi:10.1016/j.jdent.2026.107139 (record: Europe PMC)
Frequently Asked Questions
Q: Do one-shade flowable composites hold up as well as multi-shade flowables in cervical lesions?
In this 18-month randomized trial, yes for retention: 98.4% for the one-shade flowable versus 100% for the multi-shade flowable, with no significant difference. The result applies to the two FGM products tested in non-carious cervical lesions, not to every one-shade composite.
Q: Did the one-shade composite match tooth colour as well as the multi-shade composite?
By spectrophotometer, there was no significant difference at 7 days. By examiner-rated FDI criteria at 18 months, the multi-shade composite received more "excellent/very good" colour-match scores, although all restorations assessed for colour match remained clinically acceptable.
Q: Where was the one-shade versus multi-shade flowable trial published?
It was published online on October 28, 2026 in the Journal of Dentistry (article 107139) by a team from Brazilian universities, including the State University of Ponta Grossa. The full citation and DOI are listed in the Sources section above.