Evidence map›Paper›PMID 40217188›Full record

ArticleBMC oral health2025

Chemical, optical, and morphological properties of TPU and PET-G samples after aging in artificial saliva: an in vitro study.

Edoardo Staderini, Giuseppe Chiusolo, Massimiliano Papi, Mario Palone, Luca Lombardo, Massimo Cordaro

Abstract read
In one paragraph

Article in BMC oral health, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed, 1 pooled it
–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

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed, 1 synthesis or guideline pooled it.

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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.

Edoardo StaderiniPostgraduate School of Orthodontics, Catholic University of the Sacred Heart, Largo Agostino Gemelli 8, 00168, Rome, Italy.
Giuseppe Chiusolo *School of Dentistry, Catholic University of the Sacred Heart, IRCCS "A. Gemelli" University Polyclinic Foundation, Largo Agostino Gemelli 8, 00168, Rome, Italy. giuseppechiusolo99@gmail.com.
Massimiliano PapiDepartment of Neurosciences, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168, Rome, Italy.
Mario PalonePostgraduate School of Orthodontics, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy.
Luca LombardoPostgraduate School of Orthodontics, University of Ferrara, Via Luigi Borsari 46, 44121, Ferrara, Italy.
Massimo CordaroSchool of Dentistry, Catholic University of the Sacred Heart, IRCCS "A. Gemelli" University Polyclinic Foundation, Largo Agostino Gemelli 8, 00168, Rome, Italy.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThermoplastic materials, such as glycol-modified polyethylene terephthalate (PET-G) and thermoplastic polyurethane (TPU), undergo alterations due to environmental factors in the oral cavity, which can affect their composition and surface properties over time. While previous studies have explored these changes, a comprehensive characterization of TPU and PET-G properties, particularly after immersion in artificial saliva, remains limited. This study aimed to evaluate the aging process of 24 TPU and 24 PET-G dumbbell-shaped specimens before and after exposure to artificial saliva. The analysis focused on the morphological, chemical, and optical properties of the samples, including thickness, weight, and surface roughness.

methodsThe study examined 48 thermoplastic samples, equally divided between PET-G and TPU. The samples were thermoformed into standardized shapes and analyzed at three time points: after thermoforming (T0), after 7 days (T1), and after 14 days (T2) of immersion in artificial saliva at 37 °C. Measurements included weight, thickness, surface roughness, absorbance, and Fourier transform infrared spectroscopy (FTIR). Data were analyzed using one-way ANOVA to identify significant changes over time, with a significance level of p < 0.01.

resultsBoth materials exhibited significant reductions in surface roughness, with TPU showing a decrease in average roughness (Ra) from 99.43 nm at T0 to 76.53 nm at T2 (-23.02%) and PET-G decreasing from 33.25 nm to 20.19 nm (-39.27%). The root mean square roughness (Rq) in TPU declined by 41.67% (from 126.91 nm to 74.02 nm), while PET-G showed a reduction of 28.06% (from 44.98 nm to 32.35 nm). Peak-to-valley roughness (Rt) also decreased by 10.5% in TPU and 27.96% in PET-G. No statistically significant changes were observed in thickness, weight, optical density, or chemical composition (p > 0.01). The roughness disparity between TPU and PET-G persisted even after immersion in saliva.

conclusionsFollowing the simulated intraoral aging process, significant changes in surface roughness were observed in TPU and PET-G specimens. The reduction in roughness, particularly a 39.27% decline in PET-G and 23.02% in TPU, has been clinically associated with decreased plaque accumulation and reduced friction between the aligner and the teeth.

Indexed as

Polyethylene TerephthalatesPolyurethanesSaliva, ArtificialHumansIn Vitro TechniquesMaterials TestingSpectroscopy, Fourier Transform InfraredSurface PropertiesPolyethylene TerephthalatesPolyurethanesSaliva, ArtificialArtificial saliva agingClear alignersMorphological propertiesSurface roughnessThermoplastic materials

Identifiers

PMID40217188
PMCPMC11987292

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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.