Passive Fit of Implant-Supported Complete-Arch Prostheses Using Digital Workflows

Summary

The goal of this clinical trial is to evaluate and compare three digital workflows for the fabrication of definitive implant-supported full-arch prostheses in adult patients requiring fixed implant rehabilitation.

The main questions it aims to answer are:

* Does an automated AI-assisted digital workflow improve the passive fit of definitive full-arch implant-supported prostheses compared with manual and splint-guided alignment workflows?
* Are there differences in marginal, geometric, mechanical, and radiographic passivity among the three digital workflows? Researchers will compare manual CBCT-STL alignment, splint-guided alignment, and automated AI-assisted CBCT-STL alignment to see if the degree of digital workflow automation affects the passive fit of definitive full-arch implant-supported prostheses.

Participants will:

* Be adults (18 years and older) indicated for fixed implant-supported full-arch rehabilitation.
* Receive a definitive, screw-retained, full-arch implant-supported prosthesis fabricated using one of the three assigned digital workflows.
* Undergo standardized clinical and radiographic assessments at the time of definitive prosthesis placement to evaluate prosthesis passive fit.

Conditions

• Prosthesis and Implant Dentistry

Interventions

PROCEDURE

CBCT-STL Alignment Workflow

This procedure consists of a fully digital workflow for fabricating a screw-retained, implant-supported full-arch prosthesis using manual alignment between CBCT and intraoral scan (STL) data. Scannable healing abutments (Tissue Shapers-IF; MedicalFit, Úbeda, Spain) are attached to multi-unit abutments torqued to 10 Ncm. A CBCT scan and an intraoral scan are acquired and manually aligned in CAD software using operator-defined reference points. Passive fit is adjusted manually during the CAD design stage. The definitive framework is milled from monolithic zirconia (IPS e.max ZirCAD Prime; Ivoclar, Schaan, Liechtenstein). This workflow is operator-dependent and serves as the control procedure.

PROCEDURE

Splint-Guided Alignment Workflow

This procedure employs a rigid reference splint with metallic abutment cylinders to guide dataset alignment for full-arch prosthesis fabrication. Scannable healing abutments (Tissue Shapers-IF; MedicalFit, Úbeda, Spain) are connected to multi-unit abutments torqued to 10 Ncm. The splint is attached intraorally and scanned extraorally to capture implant positions. The splint and intraoral scans (STL) are imported into CAD software, where manual alignment is performed using the splint as a reference. The final monolithic zirconia framework (IPS e.max ZirCAD Prime; Ivoclar, Schaan, Liechtenstein) is designed and milled via CAD/CAM. This workflow is operator-dependent and used as an active comparator.

PROCEDURE

Automated AI-Assisted CBCT-STL Alignment Workflow

This procedure uses AI-assisted software (Pdental, MedicalFit, Úbeda, Spain) to automate the alignment of CBCT and intraoral scan (STL) datasets for full-arch prosthesis fabrication. After placement of scannable healing abutments (Tissue Shapers-IF; MedicalFit), intraoral and CBCT scans are obtained. The software automatically detects healing abutments, performs CBCT-STL registration, and corrects deviations greater than 120 µm to achieve passive fit within clinically acceptable limits. The corrected digital model is exported in STL format for CAD design and CAM milling of a monolithic zirconia screw-retained prosthesis (IPS e.max ZirCAD Prime; Ivoclar, Schaan, Liechtenstein). This workflow minimizes operator dependency based on an AI-assisted automation. .

Sponsors & Collaborators

• Universidad Complutense de Madrid

  lead OTHER

Principal Investigators

• Miguel A Gómez Polo, DDS, PhD · School of Dentistry, Complutense University of Madrid. Pza Ramon y Cajal S/N. 28040 Madrid, Spain

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-01-01

Primary Completion

2026-12-01

Completion

2027-03-01

Countries

• Spain

Study Locations