Time-dependent microbiome dynamics in orthodontic thermoplastic materials: comparing PETG and TPU.

Clin Oral Investig

Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Fudan University, Shanghai, China.

Published: July 2025


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Objectives: This study compares the effects of thermoplastic polyurethane (TPU) and polyethylene terephthalate glycol (PETG) aligners on the oral microbiome and salivary pH during orthodontic treatment.

Materials And Methods: Ten participants wore TPU and PETG aligners for 24 h. At five time points (1 min, 4, 8, 12, and 24 h), saliva was collected for pH analysis, and microbial samples were taken from both aligner and supragingival plaque surfaces for 16S rRNA sequencing. Statistical analyses included repeated Measures ANOVA for pH, Kruskal-Wallis test for alpha diversity, PERMANOVA for beta diversity, and two-way ANOVA for microbial composition.

Results: In Group PETG, salivary pH significantly decreased from T0 to T4 (p < 0.05). No significant changes in alpha or beta microbiota diversity were observed in either group. Microbial shifts in supragingival plaque microbiomes were detected at T8 in Group PETG, while in Group TPU, these changes became evident between T12 and T24. In aligner microbiomes, Group TPU showed significant reductions in Veillonella, Actinomyces, and Fusobacterium at T24 (p < 0.05). In contrast, Group PETG exhibited significant increases in Streptococcus from T4 to T24 (p < 0.05) and Fusobacterium from T0 to T4 (p < 0.05), followed by a decline from T4 to T24 (p < 0.01).

Conclusions: PETG aligners caused significant reductions in salivary pH at T4 and triggered pronounced fluctuations at T8 in supragingival plaque microbiomes. TPU aligners caused a delayed decline in salivary pH between T8 and T12 and drove distinct structural shifts during prolonged wear from T12 to T24.

Clinical Relevance: Material choice based on microbial impact highlights the need for personalized aligner materials and cleaning cycles.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC12234582PMC
http://dx.doi.org/10.1007/s00784-025-06441-yDOI Listing

Publication Analysis

Top Keywords

petg aligners
8
time-dependent microbiome
4
microbiome dynamics
4
dynamics orthodontic
4
orthodontic thermoplastic
4
thermoplastic materials
4
materials comparing
4
petg
4
comparing petg
4
petg tpu
4

Similar Publications

Mussel-inspired nanocellulose scaffold for antibacterial and anti-inflammatory coating for clear aligners.

Colloids Surf B Biointerfaces

August 2025

Department of Orthodontics, Stomatological Center, Guangdong Provincial High-level Clinical Key Specialty & Guangdong Province Engineering Research Center of Oral Disease Diagnosis and Treatment, Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, China. Electronic address: peitao@pkusz

Aesthetic demands in contemporary dentistry have driven the widespread adoption of clear aligners (CAs), yet their polymeric substrates lack intrinsic antibacterial and anti-inflammatory functionality, predisposing the periodontium to inflammation during prolonged wear. Here, we present a multifunctional surface coating for PETG-based CAs, comprising dopamine-grafted TEMPO-oxidized bacterial cellulose nanofibers (TOBC-DA), curcumin (Cur), and polyvinyl alcohol (PVA), applied via a facile spin-coating process. TOBC-DA serves as a bioadhesive matrix that forms a robust, long-lasting bond with PETG while maintaining chemical stability in simulated oral conditions.

View Article and Find Full Text PDF

Auxiliary buttons are often required in clear aligner therapy for elastic traction. We introduce an adhesiveless flame-fusion technique for affixing auxiliary metal buttons to clear aligners, aiming to eliminate the extra chair time, occasional debonding, and translucent haze associated with resin adhesives. Round‑base stainless‑steel buttons are grasped with locking forceps, heated in an alcohol flame (~600-650 °C for 10-15 s), and immediately pressed with moderate manual pressure (~5 N) for 5-10 s onto 0.

View Article and Find Full Text PDF

Background: The purpose of this study was to evaluate the dimensional stability of PET-G clear aligners.

Material And Methods: Two starting passive aligners of different thicknesses (0.75 mm and 0.

View Article and Find Full Text PDF

Viscoelastic Creep of 3D-Printed Polyethylene Terephthalate Glycol Samples.

Polymers (Basel)

July 2025

Institute for Mechanics of Materials, Faculty of Science and Technology, University of Latvia, Jelgavas Str. 3, LV-1004 Riga, Latvia.

This article explores the viscoelastic properties of polyethylene terephthalate glycol samples created by fused filament fabrication, emphasising the anisotropy introduced during fabrication. The samples were fabricated with filament direction within samples aligned along the principal axis or perpendicular. A group of samples was loaded with constant stress for 5 h, and a recovery phase with no applied stress was observed.

View Article and Find Full Text PDF

Time-dependent microbiome dynamics in orthodontic thermoplastic materials: comparing PETG and TPU.

Clin Oral Investig

July 2025

Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases, Fudan University, Shanghai, China.

Objectives: This study compares the effects of thermoplastic polyurethane (TPU) and polyethylene terephthalate glycol (PETG) aligners on the oral microbiome and salivary pH during orthodontic treatment.

Materials And Methods: Ten participants wore TPU and PETG aligners for 24 h. At five time points (1 min, 4, 8, 12, and 24 h), saliva was collected for pH analysis, and microbial samples were taken from both aligner and supragingival plaque surfaces for 16S rRNA sequencing.

View Article and Find Full Text PDF