The goal of this clinical trial is to compare the 18-month clinical success rates of three caries management approaches in primary molars of 60 healthy children aged 4-8 years attending the Department of Pediatric Dentistry at Erciyes University, using a randomized split-mouth design involving 180 treated teeth. The three approaches include the Hall Technique, Silver Diamine Fluoride, and the conventional "drill-and-fill" restorative approach using compomer material. The study will also evaluate pain perception during treatment, child behavior, and treatment acceptability from the perspectives of patients, parents, and dentists. The main questions it aims to answer are:

• Do minimally invasive approaches (Hall Technique and Silver Diamine Fluoride) achieve comparable or superior 18-month clinical success rates compared to the conventional drill-and-fill restorative treatment?
• Do minimally invasive approaches result in lower pain perception, improved child behavior, and greater treatment acceptability compared to the conventional drill-and-fill approach?

Researchers will compare the three treatment approaches applied to different teeth within the same child to see if minimally invasive methods provide similar or improved clinical outcomes and better patient-centered outcomes over 18 months compared to the conventional approach.

Participants will:

• Contribute three eligible primary molars per child (180 teeth in total).
• Have each tooth randomly assigned to one of the three treatment approaches following a split-mouth design.
• Receive all three interventions within the same participant, with each treatment applied to a different tooth.
• Attend scheduled follow-up visits at 1 month after completion of all interventions, and at 6, 12, and 18 months (final follow-up) for clinical and radiographic evaluation of each treated tooth.
• Provide assessments of pain perception and treatment experience, with additional evaluations completed by parents and treating dentists.

This randomized split-mouth clinical trial was designed to evaluate and compare the clinical performance and patient-centered outcomes of three different caries management approaches in primary molars of children.

Dental caries remains one of the most prevalent chronic diseases in childhood. Minimally invasive strategies such as the Hall Technique (HT) and Silver Diamine Fluoride (SDF) have gained increasing attention as alternatives to conventional restorative treatment, particularly in young or anxious pediatric patients. However, comparative clinical data evaluating long-term outcomes and patient-centered measures between these approaches and conventional restorative treatment remain limited.

A total of 60 healthy children aged 4-8 years requiring restorative treatment for at least three primary molars were included. Using a split-mouth design, each child contributed three eligible primary molars (total: 180 teeth). Within each participant, teeth were randomly allocated to receive one of the following interventions:

Hall Technique (placement of a preformed metal crown without caries removal or tooth preparation)

Silver Diamine Fluoride application

Conventional caries removal followed by restoration using compomer material (drill-and-fill approach)

The split-mouth design was selected to minimize inter-individual variability by allowing direct intra-patient comparison of the three treatment modalities.

Clinical and radiographic evaluations were performed at 1 month after completion of all interventions and at 6, 12, and 18 months. The primary outcome measure was 18-month clinical success of each treated tooth. Secondary outcomes included pain perception during treatment, child behavior, and treatment acceptability as assessed by patients, parents, and treating dentists.

This study aims to provide comparative evidence regarding the effectiveness and acceptability of minimally invasive versus conventional restorative approaches in pediatric dentistry.

Inclusion Criteria:

• Children aged 4 to 8 years.
• Systemically healthy children without any medical or syndromic conditions.
• Frankl Behavior Rating Scale score of 3 (positive) or 4 (definitely positive).
• Presence of at least three unrestored, asymptomatic primary molars with active occluso-proximal dentine caries lesions (ICDAS codes 3, 4, or 5).
• Written informed consent obtained from parents or legal guardians, with willingness to attend follow-up visits.

Exclusion Criteria:

• Refusal to provide informed consent or unwillingness to participate.
• Presence of systemic disease or chronic medical conditions requiring special care or antibiotic prophylaxis.
• Teeth presenting mobility, symptoms, abscess, or tenderness to percussion.
• Radiographic evidence of pulpal pathology.
• Non-restorable teeth.
• Children with severe lack of cooperation (Frankl score 1 or 2).
• Refusal of treatment for aesthetic reasons by the parent or child.

De-identified individual participant data underlying the results reported in publications (text, tables, figures).

Beginning 6 months after publication of the primary results and ending 5 years after publication.

Access to de-identified individual participant data and supporting documents (study protocol and statistical analysis plan) will be granted to researchers who provide a methodologically sound research proposal. Proposals should include a clear description of the research objectives and planned statistical analyses.

Requests will be reviewed by the Principal Investigator and the research team to ensure scientific validity and compliance with ethical standards.

Data will be shared after approval of the proposal and execution of a signed data access agreement. Proposals should be submitted to the corresponding author via institutional email.