Guided biofilm therapy versus standard cleaning for the retreatment of deep gum pockets after periodontal therapy

ISRCTN	ISRCTN51320487
DOI	https://doi.org/10.1186/ISRCTN51320487
Sponsor	Victor Babeș University of Medicine and Pharmacy Timișoara
Funder	Victor Babeș University of Medicine and Pharmacy Timișoara

Submission date: 08/09/2026
Registration date: 16/09/2026
Last edited: 09/09/2026

Recruitment status: Recruiting
Overall study status: Ongoing
Condition category: Oral Health

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Contact information

Dr Salvatore Chinnici
Principal investigator, Public

University Clinic of Periodontology, Faculty of Dental Medicine, Bd. Revoluției din 1989 nr. 9
Timisoara
300041
Romania

ORCID ID	0000-0001-8625-9272
Phone	+393275805994
Email	salvatore.chinnici@umft.ro

Prof Stefan-Ioan Stratul
Scientific

University Clinic of Periodontology, Faculty of Dental Medicine, Bd. Revoluției din 1989 nr. 9
Timisoara
300041
Romania

Phone	+40 744 521 470
Email	s.stratul@gmail.com

Study information

Primary study design	Interventional
Allocation	Randomized controlled trial
Masking	Blinded (masking used)
Control	Active
Assignment	Parallel
Purpose	Treatment
Participant information sheet	50249_PIS with ICF.pdf
Scientific title	Efficacy of guided biofilm therapy vs. standard subgingival debridement during re-instrumentation in step 3 of treatment of moderate to advanced (stage II–IV ) periodontitis: a randomized controlled trial
Study objectives	Compare clinical and microbiological outcomes of Guided Biofilm Therapy (GBT) vs. conventional SRP during repeated subgingival re-instrumentation (Step 3) in Stage II–IV periodontitis. H0: no between-group difference in patient-level pocket closure at 12 weeks, or in clinical/microbiological outcomes at 12 and 24 weeks. H1: GBT is superior to SRP for patient-level pocket closure at 12 weeks and selected secondary outcomes.
Ethics approval(s)	Approved 28/02/2025, Ethics Committee for Scientific Research, "Victor Babeș" University of Medicine and Pharmacy Timișoara (Piața Eftimie Murgu, No. 2, Timisoara, 300041, Romania; +40 256 204 400; enache.alexandra@umft.ro), ref: 34/28.02.2025
Health condition(s) or problem(s) studied	Moderate to advanced (Stage II–IV) periodontitis
Intervention	Test arm: GBT protocol — biofilm disclosure (EMS Biofilm Disclosure), supragingival air polishing (Airflow® Max), subgingival air polishing of pockets ≥4 mm (Perioflow®, Airflow®PLUS powder), residual calculus removal with minimally invasive piezoelectric instrumentation (EMS Piezon® PS / Piezon® P1 MAX) as needed; chlorhexidine 0.12% rinse twice daily for 2 weeks. Control arm: SRP — piezoelectric ultrasonic instrumentation (EMS Piezon® PS) plus manual Gracey curettes under local anaesthesia; no air polishing; same chlorhexidine rinse regimen. Both arms: single re-instrumentation session at baseline for non-responsive sites; a second protocolised re-instrumentation after the T1 (12-week) assessment, restricted to sites not meeting the endpoint, using the same allocated intervention.
Intervention type	Procedure/Surgery
Primary outcome measure(s)	Patient-level pocket closure measured using the proportion of sites per patient with probing pocket depth (PPD) ≤4 mm and no bleeding on probing (BOP), assessed by a calibrated examiner blinded to group allocation, at 12 weeks post-baseline (T1)
Key secondary outcome measure(s)	Clinical attachment level (CAL) measured using a periodontal probe at baseline, 12 and 24 weeks Bleeding on probing (BOP) measured using a periodontal probe at baseline, 12 and 24 weeks Gingival recession (REC) measured using a periodontal probe at baseline, 12 and 24 weeks Patient-reported pain, discomfort, and treatment acceptability measured using a Visual analog scale (VAS) at an immediate time point post-procedure Procedural efficiency measured using data collected on the total chairside time per treatment session at each treatment session Subgingival periopathogen load (A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia, T. denticola) measured using quantitative PCR at baseline and 24 weeks
Completion date	01/10/2027

Eligibility

Participant type(s)
Age group	Mixed
Lower age limit	18 Years
Upper age limit	75 Years
Sex	All
Target sample size at registration	80
Key inclusion criteria	1. Ages 18–75 2. Stage II–IV periodontitis 3. ≥15 teeth with PD 4–6 mm and positive BOP 4. Completed periodontal therapy Steps 1 and 2 5. Good systemic health and oral hygiene (API ≤35%, SBI ≤25%)
Key exclusion criteria	1. Heavy smokers (>10 cigarettes/day) 2. Pregnancy or lactation 3. Systemic conditions impairing healing (e.g. uncontrolled diabetes) 4. Allergy to erythritol or chlorhexidine 5. Unable to maintain adequate oral hygiene
Date of first enrolment	01/03/2025
Date of final enrolment	31/03/2027

Locations

Countries of recruitment

Romania

Study participating centres

Results and Publications

Individual participant data (IPD) Intention to share	No

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Participant information sheet			09/09/2026	No	Yes
Participant information sheet	Clinical Study Information and Informed Consent		09/09/2026	No	Yes

Additional files

50249_PIS.pdf: Participant information sheet
50249_PIS with ICF.pdf: Clinical Study Information and Informed Consent

Editorial Notes

09/09/2026: Study’s existence confirmed by the Ethics Committee for Scientific Research, "Victor Babeș" University of Medicine and Pharmacy Timișoara, Romania.