bio. retainers — the only retainers in the UK independently confirmed free from harmful microplastics. Read the bio. Standard →
/ 02 — bio.retainers

The only retainer
in the UK confirmed free
from harmful microplastics.

You wear your retainer for 8 hours every night. For years. No other retainer brand in the UK has published independent third-party testing data for microplastic particle release. We have. Results published in full.

Order now — £220 Read the results →
bio. custom retainer system — bio-derived plant polymer, zero harmful plastics, tested below detection limits for BPA and phthalates
— composition

Bio-derived plant polymer. Zero harmful plastics.
Tested below detection limits for BPA and phthalates.

"bio. retainers are the only retainers in the UK independently tested for microplastic particle release and confirmed free from harmful microplastics. This is not a marketing claim. It is a published scientific result."

— The bio. Standard

Every bio. retainer is independently tested for:

Test Method Standard Result
Microplastic particle release Simulated wear conditions (saliva simulant, 37°C, 14 days) ISO 10993-12 extraction protocol Below detection limit
BPA, BPS, BPF leachate LC-MS/MS analysis of eluate EU Regulation (EC) No 10/2011 Not detected
Phthalates GC-MS extraction analysis REACH Annex XVII Not detected
Heavy metals ICP-MS (oral simulant) ISO 10993-13 Below limits
Biocompatibility Cytotoxicity assay ISO 10993-5 Biocompatible
Polymer composition FTIR spectroscopy In-house disclosure standard Published at bio.uk/standard

Full reports by lot number at bio.uk/standard. Re-tested on every new production batch.

— The bio. material difference

What bio. is made of.

Most dental device brands never disclose their materials. We built the opposite model: every substance disclosed, every claim tested, every result published.

I
100% Microplastic-Free
No unstable plastics that fragment and leach into your body over time. bio. materials are independently tested for microplastic particle release under simulated wear conditions — confirmed below detection limits.
Confirmed by ISO 17025 lab
II
Advanced Organic Polymers
Formulated from biocompatible organic polymers derived from plant-based sources. Extreme durability, long-term safety. Full polymer composition disclosed by FTIR spectroscopy — a standard no other UK brand meets.
Plant-derived · BPA-free · phthalate-free
III
Independently Tested
Every production batch tested by an ISO 17025-accredited laboratory. Results for BPA, BPS, BPF, phthalates, heavy metals, and microplastic release published in full by lot number. Re-tested on every new production run.
— Two ways to get your retainer

At home, or at a practice.

— At home

Impression kit

Order online. Your impression kit arrives next day. Takes 10 minutes at home with step-by-step instructions and a video walkthrough. Post back in the included pre-paid packaging. Custom retainers crafted and delivered within 5 working days.

NEXT-DAY KIT · 5 WORKING DAYS RETURN
— At a practice

Digital scan

Prefer a digital scan? We'll connect you to your nearest bio. partner practice. A 15-minute appointment. No extra cost. More precise impression, same turnaround time. Recommended for complex cases.

15-MIN APPOINTMENT · NO EXTRA COST

Simple pricing.

Your retainer is custom-made to your teeth. The subscription keeps your set fresh year on year — teeth shift, materials age. An annual replacement is the standard of care.

First set
£220

Includes impression kit + custom retainers. Delivered in 5 working days.

Annual subscription
£180/yr

Annual replacement set. Fresh retainers, every year, delivered automatically.

Order your retainers

— Every bio.aligner treatment includes a free retainer set

Every bio. clear braces treatment ends with a free bio.retainer set on completion — the only retainer in the UK with published independent material testing results. The clean standard, from first tray to retention.

— Order bio.retainers

Get started.

Choose your pathway. We'll be in touch within one business day to confirm and dispatch your impression kit.

Order received.

We'll be in touch within one business day to confirm your order and dispatch your impression kit.