Guide · Hygiene
GBT vs scale and polish: what’s the difference, and is it worth £110?
Two treatments that both get called “a clean” — and they’re built on opposite logic. At City Dental Care a standard hygiene appointment is £65 and Guided Biofilm Therapy is £110. Here’s what each actually involves, and where the difference in price comes from.
A scale and polish starts with the instrument
The dental therapist scales every tooth with an ultrasonic or hand scaler to remove plaque, then polishes with a rubber cup and a gritty paste. It works — it has been the standard for decades. But it treats every surface the same whether it needs it or not, the polish is cosmetic rather than therapeutic, and a rubber cup can’t reach between teeth or below the gumline.
GBT starts with the cause
Gum disease and decay are driven by biofilm — the living film of bacteria that, left alone, hardens into tartar. Guided Biofilm Therapy is the protocol from the Swiss company EMS that removes the biofilm first, makes it visible so you understand it, and only then scales what is genuinely left. The dye shows what is left once the AIRFLOW is done, so the scraping part of the appointment shrinks to a fraction.
- Assessment — gums checked and pocket depths recorded.
- Disclosing — a harmless dye stains the biofilm so you can see exactly where plaque hides.
- Motivation — cleaning advice based on what the dye just showed, not a leaflet.
- AIRFLOW — warm water and a fine erythritol powder remove biofilm and surface stains, including between teeth and just under the gum.
- PERIOFLOW — a dedicated nozzle for deeper gum pockets.
- PIEZON ultrasonic — only the plaque the dye still shows gets scaled, on gentle settings.
- Recall — your next interval set by your own risk.
The one-minute comparison
| Scale and polish | GBT | |
|---|---|---|
| Starting point | Scale every tooth, then polish | Disclose, remove biofilm, then scale only what’s left |
| Shows you where plaque hides | Rarely | Always |
| Between teeth / under the gumline | Limited reach | AIRFLOW and PERIOFLOW reach both |
| Effect on enamel and restorations | Abrasive polishing paste | Minimally abrasive erythritol powder |
| Implants, braces, aligner attachments | Around implants, SDCEP says metal instruments do not harm the surrounding tissues when used correctly | Protocol designed to clean around them safely |
| Comfort | Depends on how much scaling is needed | Warm water, minimal scaling — often found more comfortable in trials, though not in every trial |
| Surface stains | Removed with a paste polish | Removed with AIRFLOW, which is more effective on heavy staining |
| At City Dental Care | £65 (Plans A & B) | £110 (Plans C & D) |
Where the £45 difference goes
- Biofilm — a disclosing dye shows up the biofilm (plaque), so it is removed more effectively with AIRFLOW. Both appointments remove surface stains; AIRFLOW is more effective on heavy staining.
- Time — assessment, disclosing, coaching, AIRFLOW and targeted scaling. The appointment is longer because it does more.
- Equipment and consumables — the EMS AIRFLOW system is a significant investment, and each appointment uses single-use nozzles and PLUS powder.
- Training and certification — the team is trained in the protocol. It’s a method, not just a machine. City Dental Care is certified by the Swiss Dental Academy, EMS’s own training academy, as a GBT centre of excellence in preventive professional oral care.
- What you get — comfort, reach the instruments don’t have, and a minimally abrasive powder on restorations.
How common is gum disease?
Very common, and easy to miss: NHS inform notes that many UK adults have some degree of gum disease, and that it is not always painful. The latest national examination survey, of adults in England in 2023 and 2024, found that only 7% of adults with natural teeth showed none of the gum problems the examiners checked for, which included gums that bled when gently probed, tartar and pockets deeper than 3.5mm. Scotland was not part of that survey, so read it as the nearest recent picture rather than a Scottish one.
What the research says about air polishing
Air polishing has been tested against conventional cleaning in randomised trials, and the evidence is clearest on comfort.
- Gum health. A 2022 review of eight trials found that, at gum disease maintenance visits, erythritol air polishing reduced pocket depths and bleeding about as much as hand or ultrasonic instruments, and that patients found it less painful.
- The full protocol. A 2026 review of five trials, with 231 people in total, compared GBT with conventional cleaning in people with gum disease. Patients generally found GBT more comfortable, although the differences were often not statistically significant and not every trial agreed. Effects on bleeding and pocket depths were inconsistent, and the review concluded that the evidence does not show GBT to be clinically superior.
- Tartar. Scottish guidance from SDCEP, the Scottish Dental Clinical Effectiveness Programme, notes that air polishers do not remove tartar, so scaling is still needed where it is present. That is why GBT keeps a scaling step.
Do you need a scale and polish every six months?
Not automatically. A 2018 Cochrane review of two UK trials in regularly attending adults without severe gum disease found that a scale and polish scheduled every six or twelve months made little or no difference to gum bleeding over two to three years, compared with having one only when the dentist judged it necessary or the patient asked. Tartar was slightly lower with the scheduled visits. One of those two trials, IQuaD, ran for three years in NHS practices in Scotland and north-east England. It also found no added gum-health benefit from personalised cleaning advice, though people valued both the advice and the scale and polish.
SDCEP’s guidance, which cites the Cochrane review, recommends personalised cleaning advice, and professional cleaning where tartar or inflamed gums need it, at intervals based on each person’s risk, which after treatment for periodontitis means every three to twelve months. That is why your dental therapist sets your interval by your own risk rather than the calendar, as in step 8 above, so it may be shorter or longer than six months.
So which should you have?
If you have braces or aligner attachments; if you find scaling uncomfortable or your teeth are sensitive; if you have heavy staining; or if you want to see exactly where plaque is being missed, GBT is worth the extra: the dye shows up the biofilm so it is removed more effectively, and in trials people have often found it more comfortable than conventional scaling, though not in every trial. If your gums are healthy, plaque builds slowly and you’re happy with your current clean, a standard hygiene appointment remains a perfectly good choice. Your dental therapist will tell you honestly which suits you, and the Practice Plan lets you build either into a monthly fee.
Want to see where your plaque hides?
Book a GBT appointment at 9 Earl Grey Street — £110, or included in Practice Plans C and D. Evening appointments until 8pm, Monday to Thursday (we close at 5pm on Friday).
Sources: NHS inform, Gum disease, updated 30 March 2026, and Receiving NHS dental treatment in Scotland, updated 27 July 2026; Office for Health Improvement and Disparities, Adult oral health survey 2023: clinical oral health (England only), published 9 December 2025, updated 17 December 2025; Scottish Dental Clinical Effectiveness Programme, Prevention and Treatment of Periodontal Diseases in Primary Care, 2nd edition, February 2024 (amended November 2025); Abdulbaqi HR and others, International Journal of Dental Hygiene 2022;20(1):62–74; Yein N and others, BMC Oral Health 2026;26:1078; Lamont T and others, Routine scale and polish for periodontal health in adults, Cochrane Database of Systematic Reviews 2018, CD004625; Ramsay CR and others, Improving the Quality of Dentistry (IQuaD), Health Technology Assessment 2018;22(38). Prices are the practice’s published fees.
