Color-Change Adhesives: The Future of Orthodontic Bonding?
"A closer look at how color-change adhesives can improve the orthodontic experience and outcomes."
For decades, orthodontists have relied on bonding brackets to teeth as a primary method of treatment. The advent of direct bonding techniques dramatically reduced the need for full mouth bands, enhancing patient comfort, aesthetics, and hygiene. Now, self-etching primers have further streamlined the bonding process, reducing the steps required and making the procedure more efficient.
Despite these advancements, challenges remain. One persistent issue is the difficulty in removing excess adhesive after bracket placement. Because many adhesives share a similar shade to natural enamel, identifying and removing these remnants can be tricky, potentially leading to bacterial colonization, decalcification, and gingival irritation. This has led to the development of color-changing adhesives to aid in easier and more complete cleanup.
This article explores the innovative use of color-change adhesives in orthodontic bonding. We'll delve into a study that compares the shear bond strengths of two color-change adhesives (Transbond Plus and Grengloo) with a conventional light-cure adhesive (Transbond XT), all used in conjunction with a self-etching primer. By examining their performance over time, we can gain insights into the efficacy and potential benefits of this evolving technology.
Bonding Failure in Context
Orthodontic bracket bonding failure remains an important clinical issue, with research comparing failures associated with direct and indirect bonding techniques. A 2026 retrospective cohort study used real-world data from 5,808 teeth to identify risk factors and develop an individualized prediction tool for fixed orthodontic bracket failure. Together, these sources show a shift from measuring bonding outcomes to predicting failure risk at the tooth level.
Current Bonding Methods
Orthodontic practice currently uses three primary bonding approaches: direct bonding, indirect bonding, and CAD/CAM-based methods. Indirect bonding can reduce bracket-placement errors compared with direct bonding, but the available review notes that it takes longer to complete than the traditional procedure. Bond failure remains a recognized challenge, prompting continued efforts to improve the strength of orthodontic bonding composites and techniques for difficult clinical circumstances.
From Bands to Bonding
The history of orthodontic bonding is closely tied to changes in the materials used to attach appliances. From the inception of fixed-appliance orthodontic treatment, brackets were traditionally welded to gold or stainless-steel bands. Later developments in bonding materials changed how brackets could be attached, making the evolution of adhesive systems a central part of orthodontic history.
Color-Change Adhesives: A Clear Advantage?
A recent study investigated the bond strengths of color-change adhesives compared to traditional adhesives, focusing on ease of use and long-term effectiveness. The research team tested two color-change adhesives, Transbond Plus and Grengloo, against a control, Transbond XT, using a self-etching primer to prepare the teeth. One hundred and eighty extracted bovine incisors were used, divided into nine groups and evaluated at three different time intervals: 15 minutes, 24 hours, and 1 week.
- Preparation: Bovine incisors were mounted in acrylic resin and ground to create a uniform surface for bonding.
- Grouping: The teeth were randomly divided into three main groups, each assigned to a different adhesive: Transbond Plus, Grengloo, or Transbond XT. Each group was further divided into three subgroups for testing at different time points.
- Bonding: The teeth were prepared with Transbond Plus self-etching primer, following the manufacturer's instructions. Orthodontic brackets were bonded to the teeth using the assigned adhesive and light-cured.
- Testing: The shear bond strength was tested using a universal Instron testing machine at a crosshead rate of 1.0 mm/minute.
- Evaluation: After debonding, the Adhesive Remnant Index (ARI) was used to assess the amount of adhesive remaining on the tooth surface.
What Recent Reviews Examine
Recent research is evaluating indirect bonding across several outcomes rather than bond strength alone. A 2025 umbrella review examined accuracy, bond-failure rate, working time, chairside time, and oral hygiene associated with indirect orthodontic bracket bonding. Another 2025 systematic review focused on composite materials for fixed orthodontic retention, including shear bond strength, wear resistance, microleakage, and adhesive stability under different bonding protocols.
Unresolved Clinical Risks
Color-changing adhesives may offer practical advantages, but their clinical value should not be assumed without evidence that they maintain reliable bonding under real treatment conditions. Bond failure can depend on application technique, tooth and surface conditions, moisture control, and the demands placed on the attachment. As a result, early promise would need to be balanced against questions about durability, repair requirements, cleanup, and whether a visible color change improves outcomes rather than simply making procedures easier to monitor.
Comparing Bonding Options
Clinical comparisons of orthodontic adhesives have examined bracket-failure rates between different light-cured materials and the efficiency of each product. Comparisons of direct and indirect bonding address a different dimension: placement accuracy, workflow, and clinical time. Research on bonding to nonconventional surfaces further broadens the comparison by assessing innovative materials and protocols for effectiveness, reliability, and longevity.
The Future is Clear(ly Colored)
The study suggests that color-change adhesives, when used with self-etching primers, offer comparable bond strengths to traditional adhesives. One of the most important benefits is the color change that facilitates easier removal of excess adhesive. The Grengloo adhesive showed a particularly promising trend with less adhesive remaining on the tooth surface after debonding.
Evidence Favors Context-Specific Choices
Evidence on orthodontic bonding systems supports choosing materials and protocols according to the bracket and substrate involved. One 2024 study reported that a self-etch system was preferable for bonding ceramic brackets to zirconia crowns because it offered improved bonding efficacy and easier cleanup. A separate systematic review compared clinical bond failures among orthodontic materials using trials identified through Cochrane, Embase, and PubMed, reinforcing the need to interpret adhesive performance through clinical evidence rather than material labels alone.
Where the Field May Go
The future of orthodontic bonding may involve materials that make placement, inspection, cleanup, and repair easier while preserving dependable adhesion. Color-change technology could contribute to that direction, but its usefulness remains an issue for clinical testing rather than an established outcome. Further research will likely need to compare such materials with conventional adhesives across durability, failure rates, chairside efficiency, and patient-centered outcomes.
Beyond Adhesive Performance
Orthodontic bonding can become more difficult on enamel and other surfaces or in challenging clinical situations, making surface treatment and protocol selection important concerns. Systemic conditions also require tailored approaches: the cited review identifies Ehlers-Danlos syndrome as involving collagen fragility, rapid tooth movement, and relapse, while diabetes mellitus and juvenile idiopathic arthritis may require attention to oral complications and joint involvement. Orthodontics therefore sits within a broader health context in which treatment quality, medical conditions, emotional well-being, quality of life, and socioeconomic opportunities can intersect.
The Patient Experience
For patients, orthodontic bonding is not merely a laboratory materials question: failures can mean additional appointments, repairs, delays, or uncertainty during treatment. A color-changing adhesive could be valuable if it helps clinicians identify placement or cleanup issues without adding burdens for patients. That possibility remains provisional, however, and its real-world importance will depend on whether improved visibility translates into fewer complications and a more predictable treatment experience.
While in vitro studies provide valuable insights, further clinical research is needed to fully evaluate the performance of color-change adhesives in the complex oral environment. Factors such as saliva contamination, temperature fluctuations, and varying enamel composition can influence bonding outcomes. Testing these adhesives by bonding directly to the enamel surface (without a metal bracket) may also help evaluate the bond strength at the enamel-adhesive interface.
Color-change adhesives represent a step forward in orthodontic bonding, offering the potential to improve precision, reduce enamel damage, and enhance aesthetics. As technology advances, these innovative materials may become a standard tool in the orthodontist's arsenal, helping to create healthier, more beautiful smiles.