Traditional vs. Minimally Invasive Decay Treatments in Primary Molars: An 18-month Split-mouth Randomized Study

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.