Evidence map›Paper›PMID 41709262›Full record

ArticleBMC oral health2026

Immediate vs. delayed bonding to bleached enamel: an in-vitro evaluation of nanoscopic changes and bond strength.

Abida Saleem, Syeda Rabbab Hasan, Nusrat Jabeen, Sadia Musharraf, Hafiza Zobia Shafique, Khadija Bibi

Abstract readComparative Study
In one paragraph

Article in BMC oral health, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Abida SaleemDepartment of Mechanical and Manufacturing Engineering, National University of Science and Technology, Islamabad, Pakistan.ORCID 0000-0002-5152-5275
Syeda Rabbab HasanShifa College of Dentistry, Shifa Tameer-e-Millat University, Islamabad, Pakistan. dr_rabbab@yahoo.com.ORCID 0009-0008-1985-4686
Nusrat JabeenShifa College of Dentistry, Shifa Tameer-e-Millat University, Islamabad, Pakistan.ORCID 0009-0008-7137-2596
Sadia MusharrafShifa College of Dentistry, Shifa Tameer-e-Millat University, Islamabad, Pakistan.ORCID 0000-0001-7552-4739
Hafiza Zobia ShafiqueShifa College of Dentistry, Shifa Tameer-e-Millat University, Islamabad, Pakistan.ORCID 0000-0001-6791-047X
Khadija BibiIslamabad Medical and Dental College, Islamabad, Pakistan.ORCID 0009-0002-4340-4163

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundHigh-concentration hydrogen peroxide bleaching can induce structural and compositional changes in enamel that adversely affect adhesive bonding. While delayed bonding after bleaching has been investigated, existing evidence is largely based on bond strength outcomes alone, with limited insight into the associated nanoscale and surface alterations that influence adhesive performance. This study evaluated tensile bond strength and corresponding nanoscopic enamel changes in unbleached and bleached enamel bonded with orthodontic brackets after 24 h and a two-week delay.

methodsNinety extracted human premolars were divided into three groups (n = 30): unbleached (control), bleached with immediate bonding (after 24 h), and bleached with delayed bonding (14 days). After cleaning and polishing, the Everbrite Advanced Tooth Whitening System (CA91748USA) was employed for bleaching the coronal tooth surface, and dual-cure self-adhesive RlyxU200 was used to bond orthodontic brackets on the buccal surface of the teeth. Tensile bond strength testing was conducted using a universal testing machine. The type of bond failure was analyzed under an inverted microscope through the ARI index. Enamel surface topography and elemental changes were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively, while atomic force microscopy (AFM) was used for 3D nanoscopic characterization of surface roughness. Data were analyzed using one-way ANOVA with Tukey post hoc tests.

resultsThe highest bond strength was observed in the unbleached group (8.91 ± 2.56 MPa), which was significantly greater than both immediate (2.72 ± 0.93 MPa) and delayed (4.54 ± 2.37 MPa) bonding groups (p < 0.001). Immediate bonding showed more adhesive failures, while delayed bonding exhibited partial recovery of bond strength. SEM and AFM revealed increased surface porosity, grooves, and reduced resin penetration in bleached groups. EDX analysis demonstrated reduced calcium and phosphorus levels in bleached enamel compared to controls.

conclusionBleaching significantly compromises the enamel morphology, mineral composition, and adhesive performance at the enamel-adhesive interface. Immediate bonding after bleaching results in the weakest adhesion, whereas a two-week delay leads to partial, but incomplete recovery of bonding performance under in vitro conditions.

Indexed as

Dental BondingDental EnamelOrthodontic BracketsTooth BleachingTooth Bleaching AgentsDental Stress AnalysisHumansHydrogen PeroxideIn Vitro TechniquesMaterials TestingMicroscopy, Electron, ScanningResin CementsSurface PropertiesTensile StrengthTime FactorsHydrogen PeroxideResin CementsTooth Bleaching AgentsAtomic force microscopy (AFM)BleachingBond strengthEnamelEnergy dispersive x-ray spectroscopy (EDX)Scanning electron microscopy (SEM)Self-adhesive resin

Identifiers

PMID41709262
PMCPMC13020242

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.