Digital vs. Analog Inputs in CAD/CAM Orthodontics: A Comparative Clinical Evaluation of Palatal Expander Fabrication Workflow

36 patients with unilateral or bilateral cross bite treated with hyrax expanders fabricated through three distinct workflows: fully conventional (physical impression + manual fabrication), hybrid (physical impression + CAD/CAM fabrication), and fully digital (intraoral scanning + CAD/CAM fabrication). To evaluate and compare the clinical fit, workflow efficiency, and patient/clinician satisfaction of palatal expanders fabricated using traditional, hybrid digital, and fully digital workflows.

Study Overview

• Status: Not yet recruiting
• Conditions: Transverse Maxillary Deficiency

Detailed Description

This randomized, three-arm clinical trial aims to compare the clinical performance and workflow efficiency of tooth-borne palatal expanders fabricated using three different manufacturing workflows: fully conventional, hybrid digital, and fully digital. The study evaluates the impact of these workflows on appliance fit at delivery, efficiency of clinical and laboratory procedures, and patient- and clinician-reported satisfaction.

Following enrollment, participants will be randomly allocated into one of three equal groups using a computer-generated randomization sequence. All appliances used in the study will be Hyrax-type maxillary expanders designed to deliver comparable transverse expansion forces, with differences limited to the fabrication workflow.

In the fully conventional workflow, maxillary impressions will be obtained using conventional impression materials. Dental stone casts will be poured and used directly for appliance fabrication. The Hyrax expander will be manually fabricated on the physical cast using traditional laboratory techniques, including wire bending, band adaptation, and soldering or brazing of the expansion screw and components.

In the hybrid digital workflow, maxillary impressions will also be taken using conventional impression materials and poured in dental stone. The resulting physical casts will then be digitized using a desktop optical scanner. The scanned models will be imported into computer-aided design (CAD) software, where the palatal expander will be digitally designed. Appliance fabrication will be completed using additive manufacturing (3D printing), followed by incorporation of the expansion screw as required.

In the fully digital workflow, maxillary arches will be captured directly using an intraoral optical scanner. The generated virtual models will be used without producing a physical cast. Appliance design will be performed entirely within CAD software, and the Hyrax-type expander will be fabricated using 3D printing technology.

At appliance delivery, clinical evaluation will be performed to assess accuracy of fit, seating on the teeth, need for adjustment, and overall clinical acceptability. Any required chairside modifications will be recorded. Workflow efficiency will be assessed by documenting clinical chairside time, laboratory production time, and the incidence of remakes or significant adjustments.

Patient comfort and acceptance, as well as clinician satisfaction with appliance fit and handling, will be assessed using structured questionnaires. Data collected from all three groups will be compared to determine differences in clinical performance and workflow efficiency among conventional, hybrid, and fully digital fabrication approaches.

• Study Type: Observational
• Enrollment (Estimated): 36

Contacts and Locations

• Study Contact: Name: samar essam saleh, master of orthodontics; Phone Number: 00201093916939; Email: samaressam700@gmail.com

Study Locations

• Egypt
  • Al Mansurah, Egypt, 35516
    • Faculty of dentistry , Mansoura university
    • Contact: samar essam saleh, masters of orthodontics; Phone Number: 00201093916939; Email: samaressam700@gmail.com
    • Contact: noheir samir elshall, PhD of orthodontics; Phone Number: 01222523151; Email: samaressam700@gmail.com
    • Principal Investigator: samar essam saleh, masters of orthodontics
  • Al Mansurah, Egypt
    • Faculty of dentistry , Mansoura university

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

A total of 36 participants will be selected from outpatient clinic of orthodontics department (Faculty of Dentistry - Mansoura University). Written consent will be obtained from all legal guardians prior to enrollment.

Description

Inclusion Criteria:

• • Aged between 8 and 13 years with transverse maxillary deficiency ( with unilateral or bilateral crossbite ,with or without anterior cross bite)

  • Indicated for tooth-borne maxillary expansion
  • Good oral hygiene and cooperative behavior
  • No prior orthodontic treatment

Exclusion Criteria:

• • Craniofacial anomalies or syndromes

  • Requirement for surgically assisted expansion
  • Poor oral hygiene or high caries index

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort
Fully Analogue Workflow; Input: Physical impression.; Model: Poured in dental stone to produce physical model.; Fabrication: Hyrax expander fabricated manually by soldering/brazing components directly on the plaster cast using traditional laboratory techniques.
Hybrid Workflow; Input: Physical impression; Model: Poured in dental stone to produce physical model.; Digitization: Desktop scanning of physical model; Fabrication: CAD-designed and 3D-printed appliance (Hyrax-type),
Fully Digital Workflow; Input: Intraoral scan (IOS) using an optical scanner; Model: Virtual model used directly in design software.; Fabrication: CAD-designed and 3D-printed appliance (Hyrax-type),

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinical Fit and accuracy of expander	For the clinical fit of the palatal expander at delivery, a 5-point Likert scale could be used by the clinician as follows: Score Description; Very poor fit - Significant rocking or instability; requires remake; Poor fit - Major adjustment required (e.g., soldering, bending); Acceptable fit - Minor chairside adjustments needed; Good fit - Minimal adjustment required; Excellent fit - No adjustment needed, passive and accurate seating	Immediately after appliance insertion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Workflow and Chairside adjustment time	Time measured in minutes from impression to appliance delivery	Immediately after appliance insertion

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Expansion Efficacy	Measurement Method: Transverse dental arch width (mm) at canines / premolars / molars (digital calipers on casts/scans) and Arch length.	Through study completion, up to 3 months

Collaborators and Investigators

• Sponsor: Mansoura University

Study record dates

Study Major Dates

• Study Start (Estimated): December 25, 2025
• Primary Completion (Estimated): January 25, 2027
• Study Completion (Estimated): July 25, 2027

Study Registration Dates

• First Submitted: December 18, 2025
• First Submitted That Met QC Criteria: January 3, 2026
• First Posted (Actual): January 14, 2026

Study Record Updates

• Last Update Posted (Actual): January 14, 2026
• Last Update Submitted That Met QC Criteria: January 3, 2026
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: Digital Workflow; Intraoral Scanning; Palatal Expander; Hyrax Expander; CAD/CAM Orthodontics
• Other Study ID Numbers: MD.25.06.22

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: data with request
• IPD Sharing Time Frame: 3 years
• IPD Sharing Access Criteria: by request
• IPD Sharing Supporting Information Type: SAP

Drug and device information, study documents

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