3D-Printed Versus Band-and-Loop Versus Denovo Space Maintainers in Primary Dentition.

3D-Printed Custom Versus Conventional Band-and-Loop Versus Chairside Denovo Space Maintainers in the Primary Dentition: A Randomized Controlled Trial Protocol

Purpose of the Study When a child loses a "baby" molar early due to a cavity or injury, the surrounding teeth can shift into the empty space. This often blocks the permanent adult tooth from growing in correctly. To prevent this, dentists use a small metal device called a space maintainer.

This study aims to find out which of three different types of space maintainers lasts the longest, is most comfortable for the child, and is most efficient for the dental office to provide.

The Three Study Groups

Children in this study are randomly assigned to one of three groups:

1. 3D-Printed Custom Group: The dentist takes a digital picture (scan) of the child's mouth instead of a traditional mold. A custom-fit appliance is then 3D-printed using a specialized, medical-grade clear material.
2. Conventional Band-and-Loop Group: This is the traditional method. The dentist takes a physical mold of the teeth, which is sent to a laboratory. The child usually has to return for a second appointment a week later to have the metal appliance glued into place.
3. Denovo Chairside Group: This uses a kit of pre-made metal parts. The dentist selects the best fit and assembles the appliance right at the chairside, allowing it to be placed during a single visit.

What is Being Measured?

Researchers are following the children for 12 months to track:

Survival: Which appliance stays glued in and doesn't break most effectively?

Time: How much time does the dentist spend making and fitting the appliance?

Comfort: How much discomfort or pain did the child feel during the process?

Health: Does the appliance cause any irritation to the gums or surrounding teeth?

Who Can Participate? The study includes children between the ages of 5 and 10 who have lost at least one primary (baby) molar early and need a space maintainer to protect their future adult smile.

Importance of This Research By comparing these three methods, this study helps dentists understand if newer technologies, like 3D printing or pre-made kits, are better or more convenient than the traditional lab-made metal loops used for decades. This information will help families choose the best treatment for their children.

Study Overview

• Status: Not yet recruiting
• Conditions: Space Maintenance; Tooth Loss / Rehabilitation
• Intervention / Treatment: Device: 3D-Printed Custom Space Maintainer; Device: Conventional Band-and-Loop Space Maintainer; Device: Denovo Chairside Space Maintainer

Detailed Description

Clinical Workflow and Device Fabrication

The trial compares three distinct manufacturing and clinical delivery pathways for pediatric space maintenance:

1. 3D-Printed Custom Workflow (Experimental Arm)

   Data Acquisition: Digital impressions are captured using a high-precision intraoral scanner (3Shape TRIOS).

   Design Phase: The STL files are imported into CAD software (exocad), where a custom space maintainer is designed with a specific focus on anatomical adaptation to the abutment tooth and the edentulous ridge.

   Manufacturing: Appliances are fabricated via Stereolithography (SLA) using a Form 3B+ printer with BioMed Clear Resin. Post-processing includes a 20-minute isopropyl alcohol wash and 60 minutes of UV curing at 60°C to ensure biocompatibility and optimal mechanical properties.

   Delivery: The printed appliance is bonded using a light-cured orthodontic adhesive.

2. Conventional Band-and-Loop Workflow (Active Comparator)

   Clinical Phase: Traditional alginate impressions are taken and poured with dental stone to create a physical working model.

   Laboratory Phase: A stainless steel band (3M Unitek) is fitted to the abutment tooth on the model. A 0.036-inch stainless steel wire is contoured to the ridge and silver-soldered to the band.

   Delivery: The appliance is polished and cemented in a subsequent clinical appointment using glass ionomer cement.

3. Denovo Chairside Workflow (Active Comparator)

Selection: A prefabricated kit (Denovo Dental) is used to select a band size that fits the abutment tooth.

Assembly: A pre-formed wire loop is selected and adjusted for length at the chairside. The loop is mechanically secured to the band using the system's specialized crimping and locking mechanism, eliminating the need for soldering or laboratory delays.

Delivery: The assembled appliance is cemented during the same appointment as the initial measurement.

Randomization and Standardization Participants are allocated 1:1:1 using a computer-generated randomization sequence. To ensure consistency, all clinical procedures-including tooth preparation, scanning, and cementation-are performed by a group of calibrated pediatric dentists following a standardized protocol. For the 3D-printed group, resin batches and printer calibration are monitored weekly to ensure material integrity.

• Study Type: Interventional
• Enrollment (Estimated): 360
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: MURAD A ALRASHIDI, Pediatric Orthodontist; Phone Number: +966 55 302 2773; Email: MU.ALRASHIDI@qu.edu.sa

Study Locations

• Saudi Arabia
  • Al-Qassim Region
    • Buraidah, Al-Qassim Region, Saudi Arabia, 52571
      • Qassim University
      • Contact: MURAD ALRASHIDI, BDS, MSC; Phone Number: +966 55 302 2773; Email: MU.ALRASHIDI@qu.edu.sa

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Children aged 5 to 10 years
2. Premature unilateral loss of at least one primary first or second molar
3. Radiographically confirmed developing permanent successor at Nolla developmental stage 4 to 7
4. Parent or legal guardian able and willing to provide written informed consent, and child able to provide age-appropriate assent

Exclusion Criteria:

1. Systemic disease affecting bone metabolism or tooth development
2. Clinically significant mesiodistal space loss at screening, defined as greater than 3 mm
3. Poor oral hygiene precluding band placement, defined as a full-mouth plaque score greater than 50%
4. Known allergy or hypersensitivity to stainless steel or resin components
5. Current participation in another interventional clinical trial

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 3D-Printed Custom Space Maintainer; Participants in this arm receive a custom-designed space maintainer fabricated through a fully digital workflow. This involves an intraoral scan (3Shape TRIOS) and CAD design (exocad). The appliance is 3D-printed using stereolithography (SLA) technology (Formlabs Form 3B+) with BioMed Clear Resin, a biocompatible photopolymer. The appliance is bonded to the abutment tooth using a light-cured orthodontic adhesive during a single or subsequent clinical visit.	Device: 3D-Printed Custom Space Maintainer; A digitally designed, monolithic space maintainer. The workflow involves an intraoral scan (3Shape TRIOS) and CAD design (exocad). The device is fabricated using stereolithography (SLA) technology (Formlabs Form 3B+) with BioMed Clear Resin. It is bonded to the abutment tooth using a light-cured orthodontic adhesive
Active Comparator: Conventional Band-and-Loop; This arm represents the current clinical reference standard. Fabrication follows a traditional analog workflow beginning with an alginate impression and stone model. A stainless steel band (3M Unitek) is fitted to the model, and a stainless steel wire (0.036-inch) is hand-contoured and silver-soldered to the band. The completed appliance is polished and cemented using glass ionomer cement in a second clinical appointment.	Device: Conventional Band-and-Loop Space Maintainer; The traditional clinical reference standard. It is fabricated using an analog workflow: an alginate impression is taken to create a stone model, a stainless steel band (3M Unitek) is fitted to the model, and a 0.036-inch stainless steel wire is hand-contoured and silver-soldered to the band. The appliance is polished and cemented with glass ionomer cement.
Active Comparator: Denovo Chairside Space Maintainer; This arm utilizes a prefabricated, chairside system (Denovo Dental) designed for single-visit delivery. A pre-sized stainless steel band is selected and fitted directly to the patient's tooth. A pre-formed wire loop is then adjusted for the appropriate span and mechanically secured to the band using a specialized crimping and locking tool, eliminating the need for laboratory soldering. The appliance is cemented during the same appointment as the initial fitting.	Device: Denovo Chairside Space Maintainer; A prefabricated, stainless steel space maintainer system (Denovo Dental) designed for immediate application. A pre-sized band is selected and fitted directly to the patient's tooth. A pre-formed wire loop is adjusted for length at the chairside and mechanically secured to the band using a specialized crimping and locking tool, requiring no laboratory soldering. It is cemented during the initial appointment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Appliance Survival Rate	This measures the clinical longevity and "success" of the appliance. A "failure" is recorded if the appliance becomes completely or partially dislodged (cement failure), suffers a structural fracture, or causes significant soft-tissue trauma requiring its removal.	At 12 months from baseline
Space Maintenance Effectiveness:	Measured as the change in the mesiodistal dimension of the extraction space (in millimeters). Digital calipers or software will compare the initial space at baseline to the space remaining at the end of the study.	At 12 month from baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical and Laboratory Time (Efficiency)	Researchers will record the active working time (in minutes) for each stage of fabrication. This includes chairside time (scanning or impressions and fitting) and laboratory time (3D printing and post-processing, manual soldering, or chairside assembly).	At baseline
Gingival Health (Löe and Silness Index):	A clinical assessment of the soft tissue surrounding the abutment tooth. It will be scored from 0 (normal) to 3 (severe inflammation/bleeding) to determine if any material or design causes more irritation than others.	Baseline, at 6 months, and at 12 months.

Collaborators and Investigators

• Sponsor: Murad Alrashidi
• Investigators: Principal Investigator: MURAD ALRASHIDI, BDS, MSC, Qassim University

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: May 12, 2026
• First Submitted That Met QC Criteria: May 21, 2026
• First Posted (Actual): May 29, 2026

Study Record Updates

• Last Update Posted (Actual): May 29, 2026
• Last Update Submitted That Met QC Criteria: May 21, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Space Maintenance; Band and Loop; 3D-Printed Space Maintainer; Denovo Space Maintainer
• Additional Relevant MeSH Terms: Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases; Tooth Diseases; Tooth Loss
• Other Study ID Numbers: 26-20-3

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The investigators will share the de-identified individual participant data that underlie the results reported in the final publication. This includes primary survival data (time-to-failure), gingival index scores, and recorded fabrication times.
• IPD Sharing Time Frame: Data will become available 6 months after the primary manuscript is published in a peer-reviewed journal.
• IPD Sharing Access Criteria: Data will be made available to qualified academic researchers. For researchers who provide a methodologically sound proposal to achieve the aims of the approved proposal (e.g., meta-analysis or validation of digital orthodontic workflows). Data requestors must sign a formal Data Access Agreement to ensure the privacy of the pediatric participants. Requests should be directed to the Principal Investigator.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes