Guided Biofilm Therapy (GBT): A Hygienist's Guide to Air Polishing Equipment

Guided Biofilm Therapy (GBT) has changed how many hygienists think about the prophy appointment. Instead of starting with instrumentation, a GBT-style workflow starts by making biofilm visible, removes it with gentle air polishing, and saves ultrasonic scaling for the calculus that is actually left. This guide explains what GBT is, how the protocol works chair-side, and what equipment you need to run a GBT-style workflow in your practice.

What Is Guided Biofilm Therapy?

Guided Biofilm Therapy is a systematic, minimally invasive prevention protocol developed by the Swiss company EMS. Its core idea is simple: biofilm, not just calculus, drives caries, gingivitis, periodontitis and peri-implantitis, so removing biofilm thoroughly and comfortably should be the center of every hygiene visit.

Compared with a traditional prophy built around hand instruments, rubber cup polishing and paste, a GBT-style approach aims to:

• Remove biofilm from all surfaces, including pockets, implants and orthodontic appliances
• Reduce unnecessary instrumentation of healthy enamel, root surfaces and soft tissue
• Improve patient comfort, which helps with recall compliance
• Use disclosing to show patients exactly where biofilm is, which supports home-care coaching

The GBT Protocol, Step by Step

The EMS protocol is organized into eight steps. In plain terms, a GBT-style appointment looks like this:

1. Assess. Probe, screen and review the patient's risk factors and medical history.
2. Disclose. Apply a disclosing agent so biofilm is visible to you and the patient.
3. Motivate. Use the disclosed areas to coach the patient on home care.
4. Air polish supragingivally. Remove biofilm, stain and early calculus from enamel, restorations, implants and appliances with a low-abrasive powder.
5. Air polish subgingivally. Use a subgingival nozzle in deeper pockets (the EMS protocol references pockets of more than 4 mm up to 9 mm).
6. Scale where needed. Use an ultrasonic scaler only to remove calculus that remains after air polishing.
7. Check. Re-check for remaining biofilm and calculus, and confirm the patient is comfortable.
8. Recall. Set a recall interval based on the patient's risk.

Woodpecker's own ABC protocol (Assess, Biofilm removal, Clean) follows the same biofilm-first logic and maps closely onto these steps.

Choosing the Right Air Polishing Powder

Powder choice is one of the most important clinical decisions in a GBT-style workflow:

• Erythritol (about 14 µm). Ultra-fine and low-abrasive. Well suited to subgingival use, implants and sensitive patients.
• Glycine (about 25 µm). Low-abrasive and gentle on enamel, dentin, cementum and soft tissue. Suitable for subgingival biofilm removal and implant maintenance.
• Sodium bicarbonate (about 40 to 70 µm). Effective on heavy extrinsic stain, but too abrasive for root surfaces and subgingival use. Best limited to supragingival enamel.

Shop Woodpecker prophylaxis powders in glycine and sodium bicarbonate. Woodpecker PT-series units are also compatible with EMS AIR-FLOW erythritol powder.

What Equipment Do You Need for a GBT-Style Workflow?

At minimum, you need an air polisher that supports both supragingival and subgingival polishing with low-abrasive powders, plus an ultrasonic scaler for residual calculus. Features worth prioritizing:

• Supra and subgingival handpieces, plus disposable subgingival nozzles for pocket and implant work
• Heated water to reduce cold sensitivity, one of the biggest drivers of patient comfort
• Adjustable power and water settings so you can tailor treatment to the site and the patient
• Two powder chambers so you can switch between a stain powder and a low-abrasive powder without refilling
• A wireless foot pedal for a cleaner operatory and smoother workflow
• Training and support, because technique matters as much as the device

Combination unit or air polisher only?

A combination unit puts air polishing and ultrasonic scaling in one device, so the whole GBT-style sequence happens without switching equipment. If your operatory already has an ultrasonic scaler you like, an air-polisher-only unit is a lower-cost way to add the biofilm-removal step.

Woodpecker Air Polishers for GBT-Style Workflows

Woodpecker desktop air polishers support supragingival and subgingival air polishing with glycine, erythritol and sodium bicarbonate powders. Compare the full range on our GBT dental air polishers page:

• Woodpecker PT-E: air polisher and ultrasonic scaler with dual heating (heated water for both air polishing and scaling).
• Woodpecker PT-B: air polisher and ultrasonic scaler with heated air polishing, wireless pedal and touchscreen.
• Woodpecker PT-B Mini: compact air polisher only, with heated water and a wireless pedal. Ideal if you already have a scaler.
• Woodpecker AP-A: entry-level desktop air polisher with supra and subgingival handpieces.

Every PT-E, PT-B and PT-B Mini from GoldenDent includes support from our internal team of registered dental hygienists and a virtual training course with two free CE credits. Weighing Woodpecker against EMS? Read our Woodpecker vs. EMS Airflow comparison.

Frequently Asked Questions

What is Guided Biofilm Therapy (GBT)?

Guided Biofilm Therapy is a preventive hygiene protocol developed by EMS. It uses disclosing to show biofilm, low-abrasive air polishing to remove biofilm and stain, and ultrasonic scaling only where calculus remains.

Do I need EMS equipment to follow a GBT-style workflow?

The official GBT program is built around EMS equipment and training. Many practices follow the same biofilm-first approach (often called a GBT-style workflow) with other air polishers, such as Woodpecker units, that support supragingival and subgingival air polishing with low-abrasive powders.

Which air polishing powder should hygienists use?

Low-abrasive glycine (about 25 µm) and erythritol (about 14 µm) powders are preferred for subgingival areas, root surfaces and implants. Sodium bicarbonate (about 40 to 70 µm) is more abrasive and is best limited to supragingival stain removal on enamel.

Is air polishing safe around implants?

Low-abrasive powders such as glycine and erythritol are widely used for implant maintenance because they remove biofilm with minimal effect on implant surfaces and soft tissue. Always follow the implant and device manufacturer instructions.

Should I buy a combination unit or an air polisher only?

If you want one device for the whole appointment, choose a combination unit like the Woodpecker PT-E or PT-B. If your operatory already has a good ultrasonic scaler, an air-polisher-only unit such as the PT-B Mini is a lower-cost way to add air polishing.

Sources

• Introducing guided biofilm therapy, British Dental Journal
• Air-polishing powder options: An evidence-based guide for dental hygienists, RDH Magazine

Guided Biofilm Therapy, GBT, AIR-FLOW, PERIOFLOW and PIEZON are trademarks of EMS Electro Medical Systems S.A. GoldenDent and Woodpecker are not affiliated with EMS. Woodpecker air polishers support GBT-style workflows and are not EMS products. This article is general information, not clinical advice; always follow your practice protocols and manufacturer instructions.