Intraoral vs Extraoral Cementation of Zirconia Bridges on Ti-Bases: Microstrain Evaluation

NCT07448701 | Not Yet Recruiting

• 1 other identifier: REST-ECL-2025-06
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

This prospective clinical study compares two cementation techniques for implant-supported zirconia fixed partial dentures on titanium bases (Ti-bases): extraoral cementation performed on the working model and intraoral cementation performed chairside. Thirty clinical cases with two osseointegrated implants requiring a multi-unit zirconia restoration will be recruited at the UIC Dental Clinic. For each case, two restorations with identical design will be produced: one will be cemented extraorally (control) and an identical replica will be cemented intraorally (test). Micro-deformation will be assessed as peri-implant microstrain (µε) using a standardized strain-gauge setup and the same recording protocol for both techniques. The primary analysis compares microstrain between intraoral and extraoral cementation within each case; implant/prosthetic events will be recorded descriptively.

Conditions

Biomechanical Phenomena; Partial Edentulism

Keywords

titanium base; ti-base; zirconia bridge; intraoral cementation; passive fit; screw-retained restoration; strain gauge; CAD/CAM zirconia

Outcome Measures

Primary Outcomes (1)

• Peri-implant microstrain (µε) measured by strain gauges

  Micro-deformation around implant replicas supporting a three-unit zirconia bridge on Ti-bases, recorded with bonded strain gauges and expressed as microstrain (µε). Measurements are obtained for both cementation techniques (extraoral vs intraoral) using the same standardized recording protocol. Measurements for the extraoral (control) restoration are recorded prior to delivery, and measurements for the intraoral (test) restoration are recorded approximately 1 week after chairside cementation once the restoration is received by the laboratory.

  Pre-delivery (laboratory assessment) and ~1 week after intraoral cementation (7 ± 3 days).

Secondary Outcomes (1)

• Difference in microstrain between techniques (paired within-case)

  Pre-delivery (laboratory assessment) and ~1 week after intraoral cementation (7 ± 3 days).

Study Arms (2)

Extraoral cementation (laboratory)

ACTIVE COMPARATOR

Three-unit zirconia bridge cemented to Ti-bases extraorally on the working model under standardized laboratory conditions. Strain-gauge evaluation is performed in the laboratory prior to prosthesis delivery.

Procedure: Extraoral cementation on Ti-bases

Intraoral cementation (chairside)

EXPERIMENTAL

An identical three-unit zirconia bridge is cemented to Ti-bases intraorally following a standardized chairside protocol. The assembly is then removed and sent to the laboratory. Strain-gauge evaluation is performed approximately 1 week after intraoral cementation (7 ± 3 days).

Procedure: Intraoral cementation on Ti-bases

Interventions

Extraoral cementation on Ti-bases PROCEDURE

Extraoral (laboratory) cementation of a three-unit zirconia bridge to Ti-bases on the working model using a standardized protocol, with strain-gauge evaluation performed prior to prosthesis delivery.

Extraoral cementation (laboratory)

Intraoral cementation on Ti-bases PROCEDURE

Intraoral (chairside) cementation of an identical three-unit zirconia bridge to Ti-bases following a standardized protocol. The assembly is removed and sent to the laboratory, where strain-gauge evaluation is performed approximately 1 week later (7 ± 3 days).

Intraoral cementation (chairside)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults (≥18 years old) in good general health.
• Presence of an edentulous space requiring rehabilitation with a three-unit implant-supported fixed bridge.
• Presence of two already osseointegrated Essential Cone implants (Klockner) indicated for a three-unit implant-supported restoration in the edentulous area.
• Ability and willingness to participate and attend study visits and follow-up.
• Signed informed consent.

You may not qualify if:

• ASA III or ASA IV.
• Current or previous treatment with bisphosphonates.
• Smoking \>10 cigarettes/day.
• Extraction in the study area \<3 months before implant placement with incomplete healing.
• Guided bone regeneration in the study area with \<6 months of healing time.
• Signs of active periodontal disease (e.g., poor plaque control and/or bleeding on probing above acceptable levels).

Sponsors & Collaborators

• Universitat Internacional de Catalunya: lead

Study Sites (1)

Clínica Universitària d'Odontologia UIC Barcelona

Sant Cugat del Vallès, Barcelona, 08195, Spain

Location

Study Officials

• MARTA VALLES, DDS, PhD

  Universitat Internacional de Catalunya

  PRINCIPAL INVESTIGATOR

Central Study Contacts

MARTA VALLES, DDS, PhD

CONTACT

+34 619747903; mvalles@uic.es

Patricia Freire, DDS

CONTACT

+34 686054668; patricia.freire@uic.es

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Masking Details: Blinding was not feasible. The evaluator knows which condition is being assessed because the extraoral (laboratory) cementation is evaluated first and the intraoral (chairside) cementation is evaluated afterwards; the two conditions are not assessed at the same time. To reduce bias, the same standardized strain-gauge setup and recording protocol are used for both measurements.
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: DDS, phD

Model Details: Within-case paired comparison: for each enrolled clinical case, two identical zirconia bridges are fabricated. One is cemented extraorally to Ti-bases (control) and an identical replica is cemented intraorally (test). Microstrain is measured for both conditions using the same protocol, allowing a paired analysis within each case.

Study Record Dates

• First Submitted: February 23, 2026
• First Posted: March 4, 2026
• Study Start: March 1, 2026
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: March 4, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)