EFFICACY OF BIOMIN FLUORIDE VERSUS SODIUM FLUORIDE VARNISHES, WITH AND WITHOUT DIODE LASER ON WHITE SPOT LESIONS REMINERALIZATION IN PRIMARY TEETH.

White spot lesions (WSLs) are early manifestations of enamel caries characterized by subsurface mineral loss while the enamel surface remains clinically intact. In primary teeth, early lesions may progress rapidly, making non-invasive remineralization an important approach for preserving tooth structure and preventing progression to cavitation. Fluoride varnish is widely used for the management of early enamel lesions; however, conventional fluoride varnishes may have limited retention on the tooth surface and may primarily promote remineralization near the enamel surface.

Bioactive glass-containing materials have been developed as an alternative or adjunctive remineralization strategy. Biomin fluoride varnish incorporates bioactive glass capable of releasing calcium, phosphate, and fluoride ions in the oral environment. According to the protocol, the sustained release of these ions may promote formation of fluorapatite and potentially provide deeper and longer-lasting remineralization of early enamel lesions.

Low-level diode laser irradiation has also been proposed as an adjunct to topical fluoride treatment. The protocol describes laser irradiation as potentially increasing enamel resistance to acid attack and enhancing fluoride uptake. However, previous findings cited in the protocol are not consistent: some studies have suggested a synergistic effect between laser irradiation and remineralizing agents, whereas other studies have not demonstrated an additional benefit when laser treatment is combined with fluoride or Biomin products. The protocol therefore identifies a need for clinical evaluation of these approaches in primary teeth.

This study is designed as a four-arm, parallel, randomized controlled clinical trial. Participants meeting the study criteria will be randomly allocated to receive one of the study treatment approaches. The allocation will be computer-generated with an equal allocation ratio, and treatment assignment will be concealed until the intervention. The outcome assessor will remain blinded to treatment allocation.

The study will evaluate the clinical and quantitative changes occurring in active, non-cavitated white spot lesions during a 6-month follow-up period. Lesion status will be monitored using clinical assessment with the International Caries Detection and Assessment System (ICDAS-II) and quantitative assessment using laser-induced fluorescence with the DIAGNOdent™ pen. These assessments will allow changes in lesion severity, activity, and fluorescence readings to be followed over time. Standardized photographic records will additionally be used at the end of follow-up to evaluate changes in the proportional surface area of the lesions.

Before treatment, eligible lesions will undergo baseline assessment following cleaning and standardized examination procedures. The investigator will be trained and calibrated in the use of ICDAS-II and DIAGNOdent™. Lesion activity will be assessed clinically, while DIAGNOdent measurements will provide numerical readings related to enamel demineralization. Standardized photographs will be obtained under controlled conditions to permit subsequent comparison of lesion size.

The assigned varnish will be applied according to the manufacturer's instructions. For participants allocated to the laser groups, the diode laser will be applied following varnish application using the parameters specified in the study protocol. Participants will receive post-treatment instructions concerning fluoride-containing products and eating and drinking following varnish application. At the 3-month visit, the assigned treatment will be reapplied, followed by the same post-application instructions.

Follow-up examinations will take place at predetermined intervals during the 6-month study period. Clinical and DIAGNOdent assessments will be repeated during follow-up, while standardized photographic assessment will be performed at the final visit. All follow-up assessments will be conducted by the same calibrated examiner, who will remain unaware of the treatment allocation.

The study is intended to determine whether the incorporation of bioactive glass into a fluoride varnish and/or the addition of low-level diode laser irradiation is associated with greater improvement in early white spot lesions than conventional fluoride varnish alone. The findings are expected to provide clinical evidence regarding the use of these non-invasive approaches for the management of early carious lesions in primary teeth.

The protocol states that written informed consent will be obtained from the parent or guardian before participation. The study activities will be conducted in accordance with the ethical requirements of the Faculty of Dentistry, Alexandria University, and the Declaration of Helsinki. Participants and their guardians will also receive oral hygiene and dietary instructions as part of the study procedures. The protocol reports that no study-related hazards or side effects are anticipated.