Oral hygiene practices are fundamental to maintaining oral health, preventing dental plaque accumulation, halitosis, stains, gingival and periodontal diseases, and improving overall quality of life. Dental plaque plays a central role in the initiation of caries and periodontal disease by lowering enamel surface pH and promoting hydroxyapatite dissolution. Toothbrushing with toothpaste remains the most widely accepted and effective method for mechanical plaque control, with its efficacy influenced by toothbrush design, brushing technique, and duration. Recently, charcoal-infused toothbrushes have been introduced as an alternative oral hygiene aid.

These brushes incorporate binchotan charcoal into nylon bristles, purportedly offering antimicrobial, deodorizing, and stain-removal properties by increasing oral pH, reducing bacterial load, and absorbing stain causing compounds. Despite growing commercial interest, scientific evidence supporting their clinical efficacy remains limited. Therefore, this randomized controlled clinical trial aims to evaluate and compare the effectiveness of charcoal-infused toothbrushes versus conventional toothbrushes in plaque reduction and stain removal among Egyptian adults. Plaque levels will be assessed using the Turesky and Gilmore modification of the Quigley-Hein Plaque Index, while stain removal efficacy will be evaluated through spectrophotometric color measurements using a Vita Easyshade device. Outcomes will be recorded at baseline and after four weeks of twice-daily brushing with standardized fluoride toothpaste. This study addresses a clear gap in the literature by providing clinical evidence on the effectiveness of charcoal-containing toothbrushes, thereby supporting evidence-based recommendations for modern oral hygiene practices.

Oral hygiene practices are essential for maintaining oral health and preventing a wide range of conditions, including dental plaque accumulation, halitosis, extrinsic staining, gingival inflammation, and periodontal diseases, all of which can significantly affect an individual's quality of life. Among these factors, dental plaque is considered the primary etiological agent in the development of both dental caries and periodontal disease. It contributes to disease progression by facilitating bacterial colonization, lowering the pH at the tooth surface, and promoting the demineralization of enamel through hydroxyapatite dissolution.

Toothbrushing with toothpaste remains the cornerstone of daily oral hygiene and the most widely accepted method for mechanical plaque control. Its effectiveness depends on multiple variables, including toothbrush design (such as bristle type and arrangement), brushing technique, frequency, and duration. In addition to plaque removal, toothbrushing also plays an important role in controlling extrinsic stains, thereby contributing to improved dental esthetics.

In recent years, charcoal-infused toothbrushes have been introduced as an alternative oral hygiene aid and have gained increasing popularity in the consumer market. These toothbrushes typically incorporate activated charcoal-often derived from binchotan charcoal-into nylon bristles. Activated charcoal is characterized by a highly porous structure and large surface area, which theoretically enhances its ability to adsorb organic compounds. Manufacturers claim that charcoal-infused toothbrushes offer multiple benefits, including antimicrobial activity, deodorizing effects, and improved stain removal. These effects are proposed to occur through mechanisms such as increasing oral pH, reducing bacterial load, and binding stain-causing chromogens on the tooth surface.

Despite these claims and widespread commercial promotion, the scientific evidence supporting the clinical effectiveness of charcoal-infused toothbrushes remains limited and inconclusive. Most available studies have focused on charcoal-containing dentifrices rather than toothbrushes, and clinical trials-particularly those involving adult populations-are scarce. Furthermore, existing data show inconsistent findings regarding their superiority over conventional toothbrushes in plaque control and whitening efficacy.

Therefore, the present randomized controlled clinical trial was designed to evaluate and compare the effectiveness of charcoal-infused toothbrushes versus conventional nylon toothbrushes in reducing dental plaque and removing extrinsic stains among Egyptian adults. Plaque accumulation was assessed using the Turesky and Gilmore modification of the Quigley-Hein Plaque Index, a validated and widely used clinical index. Stain removal efficacy was evaluated objectively using spectrophotometric color measurements (ΔE, ΔL*, Δb*) obtained with a Vita Easyshade device, allowing for precise and reproducible assessment of tooth color changes.

All participants were instructed to perform twice-daily toothbrushing using a standardized fluoride toothpaste to control for confounding variables. Clinical outcomes were recorded at baseline and after a four-week follow-up period. By employing a randomized controlled design and objective measurement tools, this study aims to provide reliable clinical evidence regarding the actual benefits of charcoal-infused toothbrushes.

This study addresses a significant gap in the literature by being among the first to evaluate the stain removal efficacy of charcoal toothbrushes in an adult population within a clinical setting. The findings are expected to contribute to evidence-based recommendations and guide both clinicians and patients in making informed decisions regarding the use of modern oral hygiene products

Inclusion Criteria:

• Subjects who will be given a consent to participate in the study, between 21 to 50 years old, with an original plaque score recorded above 2, and presence of at least twenty long lasting natural teeth (excluding wisdom tooth, teeth with orthodontic appliances) were included in the study.

Exclusion Criteria:

• Subjects with any physical constraints that might prevent normal oral hygiene procedures, history of sensitivity to toothpaste, use of interdental aids (interdental floss, mouth rinses, etc), pregnant or breastfeeding females, subjects under medication such as anti inflammatory, antiepileptic and antihypertensive, medically compromised patients (systemic diseases such as cardiovascular disease, diabetes, etc), evidences of gingival or periodontal diseases or trauma at baseline, any lesion of hard and soft tissue, were excluded from the study.