NCT07134114

Occlusal Impact of Hall Crowns in Primary Molars

Comparative Evaluation of Occlusal Changes Following Hall Technique Crowns in Different Primary Molar Groups: A Randomized Controlled Clinical Trial

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 60 (estimated)
• Sponsor: Ankara Yildirim Beyazıt University · Academic / Other
• Sex: All
• Age: 7 Years – 10 Years
• Healthy volunteers: Accepted

Summary

Hall Technique is a non-invasive restorative approach for managing carious primary molars, increasingly used in pediatric dentistry due to its simplicity and patient tolerance. This study aims to evaluate and compare the occlusal changes that occur following Hall crown placement on different primary molar groups (maxillary first molar, maxillary second molar, mandibular first molar, mandibular second molar) using digital model analysis.

Detailed description

The aim of this clinical study is: * to evaluate the occlusal changes that occur following the Hall Technique in different primary molar groups. * to investigate whether the molar group (first vs. second) and jaw location (maxilla vs. mandible) influence the degree or pattern of occlusal adaptation. A total of 60 healthy children aged between 7 and 10 years will be recruited from the Pediatric Dentistry Clinic at Ankara Yıldırım Beyazıt University, Faculty of Dentistry. Patients must have at least two primary molars requiring restorative treatment and meet all inclusion criteria. After obtaining informed consent from parents and assent from the child, one eligible primary molar per participant will be randomly selected for Hall crown placement using a computer-generated allocation system. Based on the selected tooth, participants will be stratified into four groups: Group 1 (Maxillary first primary molar), Group 2 (Maxillary second primary molar), Group 3 (Mandibular first primary molar), and Group 4 (Mandibular second primary molar). Following group allocation, all other necessary dental treatments-including conventional restorations, endodontic procedures, and preventive interventions-will be completed to eliminate potential occlusal interferences. One week after the completion of all dental treatments other than the Hall Technique, a baseline digital intraoral scan will be obtained using the Trios 3 scanner (3Shape, Copenhagen, Denmark), prior to crown placement on the designated primary molar. The Hall Technique will then be applied without local anesthesia or any caries removal. Debris will be gently cleared from the cavity, and airway protection will be ensured using gauze or elastoplast fixation. An appropriately sized preformed stainless-steel crown will be filled with glass ionomer cement (3M Ketac Cem) and seated on the tooth. The child will be instructed to bite firmly to ensure crown placement, or finger pressure will be used if necessary. Excess cement will be removed and interproximal contacts will be cleaned with dental floss. Digital intraoral scans will be repeated at three additional time points: immediately after crown placement (T1), at two weeks (T2), and at one month (T3) post-treatment. Superimposition and occlusal analysis will be conducted using Trios CAD (Computer-Aided Design) software to evaluate changes in occlusal parameters over time. Following parameters will be quantitatively assessed: * Positional change (in mm) between the mesiobuccal, distobuccal, mesiolingual/palatal, and distolingual/palatal cusp tips of the Hall-treated tooth, as well as the cusp tips of the opposing teeth in maximum intercuspation with this tooth. * Positional change (in mm) of the cusp tip of the maxillary primary canine on the same side as the treated tooth * Positional change (in mm) between the mesiobuccal cusp tips of all permanent first molars, * Change in anterior occluso-vertical dimension (in mm) * Change in posterior occluso-vertical dimension (in mm) * Change (in mm²) in the surface area of maximum occlusal contact regions, based on digital bite registration records. Statistical analysis will involve comparing changes in linear (mm) and surface area (mm²) measurements across the four study groups at multiple time intervals (T0-T1, T0-T2, T0-T3, T1-T2, T1-T3, and T2-T3). Data distribution will be assessed using the Shapiro-Wilk test. Group comparisons will be performed using ANOVA, Kruskal-Wallis, chi-square, and two-way mixed ANOVA or F1-LD-F1 design, as appropriate. Bonferroni correction will be applied for post hoc tests, and p ≤ 0.05 will be considered statistically significant. Analyses will be conducted using SPSS v.23 and R software.

Conditions

• Dental Caries
• Dental Occlusion
• Pediatric Dentistry

Interventions

Type	Name	Description
PROCEDURE	Hall Technique	Procedure: Hall Technique A preformed stainless-steel crown will be placed on a primary molar using the Hall Technique. This approach does not require local anesthesia, caries removal, or tooth preparation. Digital Scan and Bite Registration Schedule: * T0 (Baseline): Immediately before crown placement * T1 (Immediate): Immediately after crown placement * T2 (Two Weeks): Two weeks after crown placement * T3 (One Month): One month after crown placement At each time point (T0-T3), digital scans of both the upper and lower arches will be obtained, and a bite registration will be recorded. These records will be used to generate three-dimensional digital models, which will be analyzed to assess occlusal relationships and monitor changes over time.

Timeline

• Start date: 2025-09-15
• Primary completion: 2026-07-15
• Completion: 2026-12-15
• First posted: 2025-08-21
• Last updated: 2025-11-20

Locations

1 site across 1 country: Turkey (Türkiye)