Clear Aligner Cleaning: Brushing, Chlorhexidine, and BlueM Effects on Oral Microbial Ecology and Periodontal Indices

Summary

This randomized crossover study will assess how three aligner-cleaning methods affect early supragingival oral microbial ecology and periodontal health in adults using clear aligners. Each participant will complete three (1-month) periods in a randomized sequence with (1-week) washouts between periods:

1. Mechanical toothbrushing with fluoride toothpaste (control),
2. Chlorhexidine (CHX) mouthwash, and
3. an oxygen-based cleanser (BlueM).

Primary ecological outcomes focus on early dysbiosis indicators Fusobacterium nucleatum and Prevotella intermedia measured on retrieved aligner inner-surface biofilm and on supragingival plaque at the gingival margin. Secondary outcomes include periodontal indices (plaque index, gingival index, bleeding on probing) at index teeth and the host inflammatory marker MMP-8 in matrix-paired extracts (plaque and aligner).

Study visits occur at baseline and at the end of each 1-month period. Supragingival plaque is collected from the upper and lower first molars and central incisors; used aligners are swabbed immediately after removal. Participants are instructed to wear aligners about 22 hours/day, change trays every 10 days, remove aligners for meals and oral hygiene, and drink only water while aligners are in.

Laboratory procedures include blinded culture enumeration under coded labels (performed by a single trained operator, FA), confocal laser scanning microscopy, and RNA isolation with species-specific qRT-PCR; microscopy is conducted unblinded after decoding. The study will determine whether chlorhexidine or an oxygen-based cleanser produces more favorable early ecological changes and periodontal outcomes than mechanical brushing alone in clear aligner therapy.

Conditions

• Gingivitis
• Dental Plaque

Interventions

BEHAVIORAL

Mechanical toothbrushing (fluoride toothpaste)

Control oral-hygiene period using mechanical toothbrushing with a fluoride-containing toothpaste, per standardized study instructions, for the assigned 1-month period. No chlorhexidine or oxygen-based cleanser is used during this period; aligners are removed for oral-hygiene procedures per protocol.

DRUG

Chlorhexidine mouthwash (0.2%)

Chlorhexidine mouthwash used per standardized study instructions for the assigned 1-month period. No oxygen-based cleanser is used during this period; aligners are removed for mouthrinse use and oral-hygiene procedures per protocol. A 1-week washout without cleaning products separates periods.

OTHER

Oxygen-based cleanser

Oxygen-based cleanser (BlueM) used per standardized study instructions for the assigned 1-month period. No chlorhexidine is used during this period; aligners are removed for product use and oral-hygiene procedures per protocol. A 1-week washout without cleaning products separates periods.

Sponsors & Collaborators

• Riyadh Elm University

  lead OTHER

Principal Investigators

• Dr. Faisal A Althobaiti, BDS · Riyadh Elm University

• Dr. Nancy M Ajwa, MSc · Riyadh Elm University

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-02-28

Primary Completion

2026-10-31

Completion

2026-10-31

Countries

• Saudi Arabia

Study Locations